Monday, December 30, 2019
Decision Based Modeling Case Study - 876 Words
Decision Based Modeling The purpose of this paper is to review a business case presented by a laboratory services company and make recommendations on how best to incorporate required changes and the impact it will have on current and future operations. Prior to making any recommendation, a review of the companyââ¬â¢s existing business operations is required. This assessment will afford the decision maker various tools in which informed decisions can be made. More times than not, multiple options are available and can prove successful, even dealing with situations that require complex decisions. There are several decision based modeling schemes out there, but for this paper three models were compared against the business case to determine which afforded the greatest supportability. Graham Allison published The Essence of Decision in 1971; Allison suggested that there are three perspectives that one might use to analyze a major decision: (1) the rational model, (2) the organizational process model, a nd (3) the governmental politics model which will be referred to as the collaborative model (Nahavandi,A., Denhardt, R., Denhardt, J., Aristigueta, M., 2015). These models will be discussed in detail and compared against the business case presented by the laboratory services company. Also, there are several techniques and skills that can be incorporated into these models to increase the chance of success. This paper will compare some of the options available to managementShow MoreRelatedEssay On Road Deterioration Analysis1462 Words à |à 6 Pages 3.7 Modeling techniques used for road deterioration analysis (Madanat et al., 1997) in their research exhibit incremental facility deterioration model on bridge deck sample. Since infrastructure moves from one transitional state to another with a set probability associated with the transition process, with the help of explanatory variables predicts the changes in condition of infrastructure over a period using the incremental models. The data used in this case is panel data. The previous researchRead MoreWhat Is The Role Of Bridge As Anchor Point Model771 Words à |à 4 PagesLITERATURE OVERVIEW This report gives a summary of the role of bridges as anchor points in route choice modeling. This work expands upon the prospect that people dispense more substantial amounts of significance to some specific highlights of the route, so-called anchor points. By this report, we contend that the thought of both route level attributes and anchor points would upgrade the behavioral part of route choice models and additionally their estimation and forecast capacities would be of greatRead MoreHuman Behavior Simulation For Complex Scenarios Involving Coalition Operations1566 Words à |à 7 PagesModeling and simulation as a body of knowledge provide a basis to build and execute approximations of a real world system. Being termed as an efficient decision support system, modeling and simulation is able to understand and provide better solutions to the problems in various domains. It is also capable to predict and plan the future, mitigate risks, enhance the system performance and so on. Pri marily, this modeling and simulation has emerged beyond manual methods of construction and executionRead MoreSystem Analysis and Design1287 Words à |à 6 Pagesinformation ââ¬â small case study. Module 2: Systems Analysis and Design Life Cycle (3) Requirements determination ââ¬â requirements specifications ââ¬â feasibility analysis ââ¬â final specifications ââ¬â hardware and software study ââ¬â system design ââ¬â system implementation ââ¬â system evaluation ââ¬â system modification. Role of systems analyst ââ¬â attributes of a systems analyst ââ¬â tools used in system analysis Module 3: Information gathering (3) Strategies ââ¬â methods ââ¬â case study ââ¬â documenting study ââ¬â system requirementsRead MoreApplication Of A Business Process Modeling743 Words à |à 3 PagesAbstractââ¬â BPM is typically performed by business analysts, who provide expertise in the modeling discipline. Every business requires some form o f investment and enough customers to whom its output can be sold on a consistent basis in order to make a profit. A series of action or steps to be taken in order to achieve a particular end. Business process modeling enables a common understanding and analysis of a business process. A process model can provide a comprehensive understanding of a processRead MoreScenario Analysis : The Gap Between Science And Decision Making877 Words à |à 4 Pagesdescriptions of how the future may develop based on a coherent and internally consistent set of assumptions about driving forces and key relationshipsââ¬â¢Ã¢â¬â¢ (Houghton et al. 2001:796). Scenario analysis enables an exploration of the potential impacts, risks, benefits, and management opportunities stemming from a variety of plausible future conditions. When used in conjunction with modeling, scenario analysis can help bridge the gap between science and decision making, throwing light on how land use changesRead MorePredictive Analytics And E Commerce And Internet Based Services Industry1722 Words à |à 7 Pages INTRODUCTION TO DATA MINING I ââ¬â CIS 508 Ã¢â¬Æ' Predictive Analytics in E-Commerce and Internet Based Services Industry Having data is not valuable but using data is. Analytic insights are changing the way corporates strategize and also redefining customer expectations. Analytics is the new differentiator between success and failure in the cut throat e-commerce and internet services based industry. The huge proportions of data generated from the increasing number of smart phones, the social networks andRead MoreBenefits Of Using Ppps Delivery Method886 Words à |à 4 Pagesadvantages in the other payment mechanisms. 2.0 Research Questions or Hypothesis Addressed in This Research Study â⬠¢ How beneficial to have new payment mechanisms in PPPs projects? Since every payment mechanism is associated with some risks, how would both the private and the public entities utilize these new options better than what is available now. â⬠¢ What best practice has been identified in the study to select the payment mechanisms for PPPs project in the future? After developing new payment mechanismsRead MoreCase Study : Partners Healthcare Systems1460 Words à |à 6 PagesCase Study: Partners HealthCare Systems Angela Cisco, Talia Green, Amy Mc Kinnon Glun, Morgan Rodenbaugh, and Marla Bernal Baker College Online Case Study: Partners HealthCare Systems Partners HealthCare is a non-profit, health system located in Boston that created a data based transformation (Davenport, 2013). It integrated a new system that aligned the participating organizations to cohesively run as one and to help shape the future of the organization. The system didnââ¬â¢t stop there as it was responsibleRead MoreAnchor modeling - Agile information modeling in evolving data environments (Rà ¶nnbà ¤ck and Regardt et1100 Words à |à 5 PagesAnchor modeling - Agile information modeling in evolving data environments (Rà ¶nnbà ¤ck and Regardt et al., 2010, pp. 1229--1253) Anchor modeling is suggested in the article as an agile graphical modeling technique that allows for fast adaption through extensions, and yields in older versions to be available as subset of the newest version. Even though this technique originates from data warehouse domain requirements it is to be considered as a ââ¬Å"generic modeling approachâ⬠. The basic components defined
Sunday, December 22, 2019
Socrates Stand on Democracy - 1834 Words
Reusi 1 Raye Reusi D. Ryals Writing 1 November 14, 2012 Socratesââ¬â¢ Stand on Democracy Having emphasized upon me the advantages of democracy, I have always believed that it is the best system to implement in a country. Ignoring the flaws and weaknesses of this type of system, I thought that the benefits outweigh all costs. I assume that giving the power to the people is better than having one person rule the state. However, in Platoââ¬â¢s account on the life of his mentor Socrates, we are able to see both sides of the spectrum: the pros and cons of democracy which are accounted in Platoââ¬â¢s dialogues, the Apology and the Crito. Socrates, having been accused of impiety, is brought to trial in front of the jury of Athens. In his defense, he pointsâ⬠¦show more contentâ⬠¦Yet, he implies that the people would not favor anyone that opposes injustice which seems to be the common dealings in politics. He believes that he would ââ¬Å"have died long agoâ⬠(34), altho ugh this is not his ultimate concern. What he truly cares about is ââ¬Å"not to do anything unjust or impiousâ⬠(32). Despite his criticisms on politics, Socrates is essentially reminding the people, especially those in authority, to serve a just and virtuous life. Outwardly stating the current situation of the government, he aims to provide the people a portrait of the shallow kind of democracy that they have come to maintain. Socrates seeks to prompt the majority to uphold the true sense of democracy, of fighting for justice and living life accordingly. Furthermore, Socrates uses his dialectical approach with his friend Crito in examining the contrast between the knowledge of ââ¬Å"the oneâ⬠and the pseudo-knowledge of ââ¬Å"the manyâ⬠. He uses an analogy of a man involved in physical activities, whom must listen to the advice of the true expert in his training, rather than the opinions thrown by other people who barely know anything about these activities. Anyon e who places a higher regard to the thoughts of the majority, rather than to the knowledge of the one who possess it, puts himself on greater ââ¬Å"harmâ⬠(47). Socrates adds that if we disobey the one who seeks toShow MoreRelatedSocrates As A Martyr And Socrates927 Words à |à 4 PagesIn philosophy class this semester we spoke a lot about Socrates and his trial. We were required to read the dialogue ââ¬ËApologyââ¬â¢ by Plato. The ââ¬ËApologyââ¬â¢ Dialogue is what Plato recorded during the speech Socrates gave to the court defending himself against the charges of corrupting the young, and by not believing in the gods in whom the city believesâ⬠these two were the main charges, but underneath that there were also other significant charges such as being considered an antidemocratic or pro-SpartanRead MoreIdeals of Democratic Citizenship in Funeral Oration by Pericles1264 Words à |à 6 PagesIdeals of Democratic Citizenship in Funeral Oration by Pericles When dealing with the extent to which Socrates is a good example for following the ideals of democratic citizenship, a good source to use as a point of comparison to his life is the principles laid out about that citizenship by Pericles in his Funeral Oration. In the Oration, Pericles brought forth certain ideas about Athenian democracy and how its citizens should live their lives in accordance with it. He held these views to be paramountRead MoreEssay about War in Iraq713 Words à |à 3 Pagesphilosophy class we talked about a very smart philosopher named Socrates. Socrates had different ideas for democracy and different presidents. He talked about who and how should rule the country, for it to be a kind of a utopia. Socrates tried to make everybody feel good and live even greater, but it did not worked out very nice for him. You probably ask me why? Of course I can tell! His own people killed him. The ââ¬Å"presidentsâ⬠or princes whom Socrates wanted to rule and how they should behave were a littleRead MoreThe Emergence Of Greek City, The Apology, And The Parthenon928 Words à |à 4 Pagesof a democracy from them. Although back then, it was a system of direct, rather than representative democracy, meaning that every adult, male Athenian citizen had the right to participate in deliberations and voting in the law-making decision (Ramon 1). But today, a democracy in the United States involves everyoneââ¬â¢s opinions. Women are allowed to vote and run for office if they would like, males arenââ¬â¢t the only onesââ¬â¢ in charge. The Apology is a speech that Socrates made at his trial. Socrates wasRead MoreThe Potential Of Persuasion By Phaedrus And Life Of Demosthenes1585 Words à |à 7 Pagesskill of persuasion due to lack of knowledge and morality. Good orators can also have flaws, like Demosthenes and his susceptibility to bribery. The negative potential can be reduced if the rhetoricians are philosophers and knowledgeable of ethics. Socrates and Phaedrusââ¬â¢s discussion shows how truth is relative to whoever is most persuasive. While Plutarch does not state any solutions to reducing negative potential in rhetorical speeches, Platoââ¬â¢s method for giving a persuasive speech worthy of praiseRead MoreHow Did Ancient Greece Influence Western Civilization951 Words à |à 4 Pagesancient Greeks. The Greeks changed the way the world looks at art, math, architecture, philosophy, sports, and drama. Without the ancient Greeks, the modern world would not be the same. Men such as Socrates, Plato, and Arist otle changed the way we look at philosophy. The Athenians created the first known democracy, setting the stage for future governments. The Euclidian Theorem and the Pythagorean Theorem among others made mathematics easier and more developed. Even current architecture can be traced backRead MoreIs Socrates Innocent or Guilty? Essay1379 Words à |à 6 PagesIs Socrates Innocent or Guilty? Living in a democracy, everyone is exposed through television and other various forms of media everyday to numerous trials by jury. Usually they are rarely given a second thought, but every once in a while along comes a specific trial which captures the attention of the entire country. This goes the same for trials throughout centuries in our past. Although they did not have the same forms of media as in this, modern era, there were still specific trials inRead MoreThe Importance Of Politics In Ancient Greek And Roman Society859 Words à |à 4 PagesGreeks can be found in The Apology of Socrates, which was written by Plato describing Socrates trial, in which he was charged for corrupting the youth. Due to the very public nature of Greek life, Socrates would spread his teachings in public squares and many of Athensââ¬â¢s young men would sit and listen to him. Although this document is called and apology it is much more like a defense by Socrates to try and prove himself innoce nt. In one part of this apology Socrates is allowed to cross interrogate hisRead MoreThe Greek Era880 Words à |à 4 Pagescomedy, modern philosophy, democracy, and the beginning of modern science. While the extravagant temples only exaggerate the magnificent and sturdy buildings the Greeks built and filled with incredible sculptures displaying arete at its finest. These things make the Greeks the most interesting culture for myself to learn and study about. Ideas and concepts created during the Greek times have become the precursors for many things was call normal today, such as: democracy, philosophy, art, and literatureRead MoreLosing Liberty: How Obama Put America On the Road to Nowhere1216 Words à |à 5 Pagesbeen countless accords on the suppression of freedom of thought, these accords span from the 21st century to the 4th century B.C. The most prominent being the prosecution of the philosopher Socrates. In the Apology of Socrates, Plato makes many points, but one key point parallels that discussed above: Socrates maintained that any individual at any cost, refuse to be coerced by any human authority or tribunal into a course which his own mind condemns as wrong. Furthermore, he asserts the supremacy
Saturday, December 14, 2019
Ethics in the Workplace Free Essays
string(123) " make individuals think before they conduct illegal and unethical activities which harm stockholders and the organization\." Bee and Buckley (2001) state that over the past few decades, corporate codes of ethics have proliferated. These codes have proved useful In Informing employees about legal requirements of the firm, addressing specific concerns and serving as guidelines for accepted practice within the organization. However, unethical acts continue to occur, as Is evidenced by the recent recall of Firestone tires and the 103 deaths that forced It. We will write a custom essay sample on Ethics in the Workplace or any similar topic only for you Order Now (p. 73) It does not matter if corporate executives are told millions of times of codes of ethical conduct as some still will conduct illegal activities. These individuals are looking to make themselves rich while other ethical individuals are looking out for the good of the organization and its stockholders. This paper will discuss the purpose statement, problem statement, topic background, necessity of study, importance of topic to the field of education as well as the potential significance of the study to scholarly literature with regard to my research study entitled Employeesââ¬â¢ Perspectives of Ethics in the Workplace. Purpose Statement The purpose of this study Is to determine whether employees demonstrate ethical behavior In the workplace Problem Statement Research is needed to explore the experiences of employees with regard to ethics or the lack thereof in the workplace today. The purpose of this study is to explore the experiences of employees in the workplace and to examine the differences and similarities of their experiences with regard to ethics in the workplace. The methodology and design of this study were derived by using the structure to establish ââ¬Å"goodnessâ⬠advocated by Armenia and Haltered (2002). Topic Background Painââ¬â¢s (1994) statement that the ethical composition of the individual defines the ethical composition of the organization Is described In his article entitled ââ¬Å"Managing for Organizational Integrity. â⬠Therefore, who you are will Influence the values of the organization due to the following reasons. First, Individualsââ¬â¢ personal values become part of the organization. Second, the supervisorsââ¬â¢ influence over the employeesââ¬â¢ actions. Third, senior management influence over lower management and employees. Fourth, internal drive of the individual to succeed. Fifth, performance pressures within the organization. Sixth, lack of punishment within the organization. Seventh, friends and/or coworker influence over other employees. Furthermore, the organizationââ¬â¢s culture influences the values of the organization as the culture of an organization defines the ethical behavior of this particular organization by defining what is right and wrong. In order to reconcile Inconsistencies between your own values and the values of the organization, an Individual must choose whether to advance his/her own interests, the organizations, or the Interests of others. For example, bribes or personal payments, gifts, or special favors Intended to Influence decision making. Individuals should report other employees for such acts as lying to supervisors, entertainment receipt in violation of company policy. These acts are violations against the organizations Code of Ethics which is a formal statement of what an organization expects in the way of ethical behavior (what behaviors are acceptable or unacceptable) and reflects senior managementââ¬â¢s organizational values, rules, and policies. However, many individuals do not report fellow co-workers for fear of not being considered a team player, do not think corrective action would be taken, fear of retribution (from management) as well as not trusting the organizational to keep the report confidential. Based on the literature, Beams, et al. (2003) experiment found that ââ¬Å"guilt had the greatest effect on intent to trade based on insider information. Expected gain, cynicism, and perceptions of the fairness of laws were also significantly associated with the intent to trade based on insider informationâ⬠(p. 320). The study also found that individuals do not necessarily engage in insider trading to gain money but to avoid a possible loss. Furthermore, the study found that insider trading was not necessarily acceptable by society as well as likely to be caught and punished for the crime. Bee and Buckley (2001) state that over the past few decades, corporate codes of ethics have proliferated. These codes have proved useful in informing employees about legal requirements of the firm, addressing specific concerns and serving as guidelines for accepted practice within the organization. However, unethical acts continue to occur, as is evidenced by the recent recall of Firestone tires and the 103 deaths that forced it. (p. 73) It does not matter if corporate executives are told millions of times of codes of ethical conduct as some still will conduct illegal activities. These individuals are looking to make themselves rich while other ethical individuals are looking out for the good of the organization and its stockholders. Dungaree and Jeepââ¬â¢s studied six individuals who engaged in criminal and unethical activities in the corporate business world. Dungaree and Speedupââ¬â¢s findings as related to these six individuals definitely support the Beams, et. Al. Experiment as these individuals knew that their activities were illegal as well as unethical. Furthermore, these activities were definitely not viewed favorably by society. Dungaree and Jeepââ¬â¢s (2001) state that ââ¬Å"all six certainly knew that they were reeking the law and most went to extra-ordinary lengths to cover up what they were doingâ⬠(p. 51). These individuals were also in high level positions, which caused individuals who knew about the criminal activities to look the other way. These individuals engaged in these activities because they were greedy and definitely not working toward organizational goals. Fell (2001) states that evidence shows that firms with ethics programs have a lower percentage of inside directors on their compensation committees than do firms without ethics programs. Firms in which boards are actively involved in the programs have more independent roads (higher percentage of independent directors and lower percentage of inside directors and are more likely to compensate outside directors with equity than are firms in which boards are not actively involved in the programs. Taken together, the evidence indicates that a board actively involved in an ethics program, and not the simple existence of an ethics program is related to the incidence of potential conflicts employees must adhere to. Maybe these ethical standards will make individuals think before they conduct illegal and unethical activities which harm stockholders and the organization. You read "Ethics in the Workplace" in category "Papers" McCall (2002) states that there should be an ââ¬Å"alternative model for adjudicating between stakeholdersââ¬â¢ conflicting claims of rights and it applies that method to determine what responsibilities corporate management might have to employees and how management might be held accountable for discharging those responsibilitiesâ⬠(p. 133). Management certainly has responsibilities to the organization, the stockholders and the employees. They are supposed to conduct business in the best interest of all. Whetstone (2003) states that (1) virtue ethics and virtue language is fluently used by practicing managers, (2) virtue engage is important to understanding managerial excellence, and (3) whereas the set of virtues defining the excellent manager can be expected to be dependent on the societal, industry, and organizational context, such a set of manager virtues can be identified and prioritize within a particular organizational milieu. The implication is that, once an organizationââ¬â¢s management better understands the meaning of the excellent manager in terms of the virtue language already used by its own employees, it is better equipped to implement a practical ethic of virtues, one helpful toward recognizing and developing excellent managers. Ethics researchers are challenged to increase their understanding of extant virtue language as the basis for a renewed development of virtue ethics theory and applications (p. 343). All organizations should train and retain managers as well as requiring all employees to attend ethical seminars and conferences on a yearly basis. This will ensure that these individuals understand the code of ethics and their responsibilities to adhere to this code of ethics. Study of Topic Importance to the Field of Education The topic of ethics is important to the field of education as well as all other fields as well as the business world. Bà ©chamel and Bowie (2004) identify three primary arguments on the practice of preferential treatment: (a) It is Just, (b) it is unjust, and (c) it is not Just but it is still permissible. The argument that is the most consistent with typical American business practices is (c) it is not Just but it is still permissible. In other words, executives and employees in the business world today take the position that unethical behavior on their part is Just the way business is conducted today. Bà ©chamel (2004) ââ¬Å"argues that even some forms of reverse discrimination can be Justified as a means to the end of a nondiscriminatory societyâ⬠(p. 27). This type of behavior is illegal and known by the executives and employees to be wrong but individuals tend to lend a blind eye when this type of behavior is noticed in the corporate world. For example, At the heart of the Enron scandal is a failure of corporate governance. Senior executives who permitted or encouraged misleading accounting treatment. An audit committee that signed off on misleading accounts. Individuals enriched by transactions with the company that employed them. A board that was ineffective in supervising senior managersââ¬â¢ actions. Weightlessnessââ¬â¢ complaints that was ignored r whitewashed. (http://www. Uncharacteristically. Com/cars/try. CGI? Articled=1679) the Board of Directors which led to its failure and bankruptcy. I believe that these individuals were only out to make themselves rich and did not care in the least about the stockholders. If the weightlessness were not disregarded, maybe Enron could have been saved before it turned into one of the largest corporate scandals in the history of the United States. The major theory that underlies workplace ethics is the stakeholder theory. According to this theory, management has an obligation to the stakeholders to make profit for the stakeholders as well as conducting business ethically. Furthermore, management must answer to the stakeholders for any wrongdoing and unethical behavior. For example, Enron executives had to answer to the stockholders as they lost their investments when the company declared bankruptcy. It is difficult for corporations to be ethical because some managers and executives are looking to profit themselves instead of what is in the best interest of the stakeholders. The trends with regard to ethical issues in the workplace are those of employees and management who are acting unethically. For example, stealing supplies, reaching the internet during work hours, leaving early and arriving late as well as management profiting for their own best interest. As time progresses, this type of behavior will grow worse as individuals in the workplace will have less morals than they do today. Potential Significance of Study to Scholarly Literature Developing theory from the data without preconceived ideas is an appropriate technique for this study on ethics in the workplace. Since studies examining the affect of ethical experiences are not documented in current literature, the data collected will be use to generate an original theory. The data obtained in this study Anton verify preexisting theory because this is not a relevant preexisting theory on this topic to be verified. This fact further substantiates a grounded theory methodology is an appropriate methodology for this study. Necessity of Study I believe that this is an important subject as ethics is lacking in individuals, groups, workplaces and the world today. I believe that most leaders, managers and employees act unethically in the workplace. Bà ©chamel and Bowie (2004) identify three primary arguments on the practice of preferential treatment: (a) It is Just, (b) it is unjust, and (c) it is not Just but it is still permissible. The argument that is the most consistent with typical American business practices is (c) it is not Just but it is still permissible. In other words, executives and employees in the business world today take the position that unethical behavior on their part is Just the way business is conducted today. Bà ©chamel (2004) ââ¬Å"argues that even some forms of reverse discrimination can be Justified as a means to the end of a nondiscriminatory societyâ⬠(p. 327). This type of behavior is illegal and known by the executives and employees to be wrong but individuals tend to lend a blind eye when this type of behavior is noticed in the corporate world. I am currently employed at The Travelers Companies as a Senior Paralegal in its Special Liability Group where I handle large commercial claims. I make my own decisions on the files that I handle including setting the reserves on a claim and supervising outside counsel until the for fifteen years. Travelers is a large company with offices all over the world so there is high growth potential as well as advancement opportunities within the Company. My department at work consists of seven claim attorneys, two secretaries and myself (the senior paralegal). My secretary, in particular, comes to work late everyday, calls in sick frequently, surfs the internet all day long, gets her hair done during work hours every four weeks, attends a weekly doctorââ¬â¢s appointment during work hours and socializes with coworkers for long amounts of time. Furthermore, we enter our own time into our human resources database, and I know for a fact that this secretary does not account for all the time she takes off, etc. In other words, she is getting more days off then she is allowed as I kept track of when she took off last year. All of these actions are a violation of my companyââ¬â¢s honesty and ethics policies. Han Cheesy Koch, El Tree H Y Boo (2004) states that organizational ethics is positively associated with not only financial performance but also employee attitudes. While it is obvious that organizational ethics are intended to guide and influence employee behavior (e. G. , in dealing with ethical dilemma and avoiding unethical situations), it is not obvious what relationship exists between organizational ethics and employee attitudes. (p. 77) Furthermore, I know that my secretary could care less about her job or the company as she has told me so on several occasions. She does not really ant to work but has to because her husband does not make much money. She would much rather sit at home and watch television. In fact, that is all she does when she is not at work. I would say that she does not have a high level of Job satisfaction and is not motivated toward company goals. I Just do not understand her lack of motivation as my company is a great place to work and we get very competitive raises each year. I believe that the situation that I have described is both an ethical decision and a moral decision. First, my secretary is not behaving to the standard which I was taught to act and behave. I have a conscious and was raised to be an honest person. My father always said that taking even a pen from work was stealing. Second, my secretary actions are morally incorrect as they go against every value that I was ever taught. When we go to work, we should be productive and work toward the goals of the organization. We should adhere to the standards of the organization as well as our own standards. My secretary is clearly not adhering to any standards whatsoever. She is taking up space and collecting a paycheck she does not deserve. Furthermore, my secretary actions since I have been with this department (for he past five years) are causing me a high level of dissonance because I believe that a personââ¬â¢s work ethic should be of the highest degree. I wish every day that I was her supervisor so I could terminate her employment. I Just cannot believe that our supervisor does not see what she does everyday and those human resources do not scrutinize the time entries more closely. I have thought about saying something to my supervisor but what this secretary does or does not do at work is none of my business. Furthermore, my secretaryââ¬â¢s actions makes me want to come in late, surf he internet instead of working, take long lunches everyday and cheat on my time also. If she can do it, so can l. However, I cannot be unethical as I was raised to be honest. Also, I have a high regard for my organizationââ¬â¢s success. However, my hotlist which you can call reporting any violations of its ethics and honestly policies. It is an 800 number and you need not give your name. I reported my secretary using this hotlist. This report is forwarded to her direct supervisor as well as human resources and an investigation is conducted. I Just could not let this activity continue as it does against every belief and value that I have. I do not feel that this type of behavior in the workplace or anywhere else for that matter should be allowed to occur. I was raised to be an honest person who worked to achieve what I desire as well as the goals of the organization. Frankly, I hope she is terminated even through she has been with my organization for twenty-five years. I do not think she adds any productive resources to my organization and is Just taking up. Conclusion In conclusion, this paper discussed the purpose statement, problem statement, topic background, necessity of study, importance of topic to the field of education as ell as the potential significance of the study to scholarly literature with regard to my research study entitled Employeesââ¬â¢ Perspectives of Ethics in the Workplace. I believe this topic is important because if individuals and the world around us continues in its current state, there will not be an ethics whatsoever when my children grow up. How to cite Ethics in the Workplace, Papers
Thursday, December 5, 2019
The Quiet American by Graham Greene free essay sample
The Quiet American, is more than a political statement about whether or not America or any other country for that matter should become involved in the affairs of another country; Greene makes the question human and personal. The novel can be read as a political and moral reflection on the opening stages of the United Statesââ¬â¢ involvement in Southeast Asia. Therefore, Greeneââ¬â¢s novel becomes a commentary on the pointlessness of the United Statesââ¬â¢ later investment of men and material in a political action that could only end, as it did for the French, in defeat. The Quiet American is considered one of Graham Greeneââ¬â¢s major achievements. The story is told with excellent characterization and sophisticated irony. The plot bears a resemblance to that of a mystery story. A crime has been committed. Who is the murderer? As in most mystery stories, as much needs to be learned about the victim as about the villain. Yet what is learned takes on political, moral, and religious significance. The story ends in mystery as well. Who exactly killed Pyle is not revealed, but the burden of the crime, like the burden of telling the story, is Fowlerââ¬â¢s. The large-scale political thesis of the novel is that American interference in the internal affairs of another country can only result in suffering, death, and defeat, and is not morally justifiable because of abstract idealism. This is not the only meaning of consequence in the novel, and given the course of later events, its importance may be blown out of proportion. The lesson, however, is clearly explained by a French aviator with ââ¬Å"orders to shoot anything in sight. Captain Trouin confides to Fowler that he detests napalm bombing: ââ¬Å"We all get involved in a moment of emotion, and then we cannot get out,â⬠he explains. Trouin understands that the French cannot win the war in Indochina: ââ¬Å"But we are professionals; we have to go on fighting till the politicians tell us to stop,â⬠he says with bitter resignation. ââ¬Å"Probably they will get together and agree to the same peace that we could have had at the beginning, making nonsense of all these years. Gre eneââ¬â¢s political objective is clearly to make a mockery the notion of a ââ¬Å"Third Forceâ⬠in Asian politics, countering the threat of Communism and replacing the rationale of colonialism as an explanation for Western involvement. Because of Greeneââ¬â¢s apparent anti-American bias, the novel was not popular in the United States. It is no wonder then that Greeneââ¬â¢s warning about Vietnam was not taken seriously, even though later events tended to validate the wisdom f his political analysis. Thus Graham Greene summarizes the lesson of Vietnam fully ten years before the American government expanded its military commitment to fill the vacuum left by the defeated French. The Quiet American is a shocking novel of political prophecy. Its mystery story characteristics perhaps better define its interest to the average reader, as Greeneââ¬â¢s unreliable narrator gradually provides the details leading up to Pyleââ¬â¢s death. The dramatic focus concerns the conflict between Fowler and Pyle over love and the politics of war, the contest between Fowler and Vigot, who knows that Fowler was responsible for Pyleââ¬â¢s death but cannot prove it, and, finally, Fowlerââ¬â¢s internal conflict, his beliefs of noninvolvement transformed by circumstances and emotion to a position of murderous intervention. ââ¬Å"Sooner or later,â⬠the Communist Heng tells Fowler, ââ¬Å"one has to take sides if one is to remain human. Perhaps Fowler finally ââ¬Å"takes sidesâ⬠because he understands how dangerous Pyleââ¬â¢s blind idealism can be, but his motives are not entirely clear because of his dependence on Phuong. Fowler does not idolize her, as does the more romantic Pyle, who sincerely cares for Phuong but is absolutely unfeeling about the rest of the native population. Pyle believes in the political theory of York Harding (a name that links a less-than-stunning American president with a patriotic war he ro) and the need for a ââ¬Å"Third Forceâ⬠(American intervention) in Vietnam. Yet Pyleââ¬â¢s naiveness is not entirely consistent with his intelligence, his training, and his Harvard degree. He is hopelessly innocent. In one of his strongest metaphors, Greene likens innocence to ââ¬Å"a dumb leper who has lost his bell, wandering the world, meaning no harm,â⬠but obviously bearing contamination and corruption with him. Fowler is a fascinating character and narrator because he simultaneously reveals and conceals so much about himself and his involvement in the story. On the one hand, he is openly contemptuous of Pyle. Like other Americans, Pyle is so obsessed with his mission to save the world that he does not register the reality around him. It is ridiculous for him to think that Phuong is an innocent he must rescue. She has stayed with Fowler because he offers her security. She leaves Fowler for Pyle because he offers her even more wealth and protection. Pyle is shocked because Fowler says he is merely using Phuong for his own pleasure and because of his need to have a woman beside him to stave off loneliness. It never occurs to Pyle that Phuong has acted just as selfishly or that Pyle imself is using people. On the other hand, Fowler is not entirely honest with himself. He claims to be disengaged, not only from politics but also from the sentiments of love Pyle professes. Yet Fowlerââ¬â¢s passionate rejection of Pyleââ¬â¢s worldview and his defense of the Vietnamese, who he believes should be allowed to work out their own destiny, free of the French, the Americans, and any other intruding power, surely reveal anything but dishonesty. In this respect, Pyle is right to see good in a man who claims to be without sense of right and wrong. In fact, Pyle loses his life because of Fowlerââ¬â¢s moral outrage. Fowler is so appalled by the bombing atrocity at the cafe that he determines to put a stop to Pyleââ¬â¢s activities. Fowlerââ¬â¢s passion is hardly consistent with his habit of staying reserved. Actually, he cares deeply about Phuong and about the Vietnamese. He believes in self-determination, which ironically is the ideology that Americans claim to support. Americans think they are supporting freedom by allying themselves with the anticommunists. Thus, there are multiple ironies in The Quiet American. Fowler says he is a pessimist, but he acts like a wounded idealist. Pyle says he is an idealist, but his involvement with anticommunist thugs places him in disparaging and brutal situations. Phuong looks like a delicate, easily manipulated, and passive victim, and yet like many other Vietnamese she is a survivor who plays one side against the other and changes according to the current political issues. Fowler declares to Vigot that he is not guilty, then retells the story of his involvement with Fowler to clear his name, yet concludes by realizing that he is guilty. The novelââ¬â¢s title is also ironic. In one sense, Pyle is quietââ¬âeven unassuming. He patiently questions Fowler about his tie to Phuong and even declares his love for her to Fowler before he marries her. Pyle is the opposite of loud, vulgar Americans such as his boss Joe, or the noisy American journalist Granger. In another sense, however, Pyle is anything but quiet. He stirs up Saigon with explosions and he turns Fowlerââ¬â¢s life into turmoil. An even greater irony is that for all their differences, Fowler and Pyle are alike in their moral earnestness. Fowler is the sophisticated European who has learned not to wear his heart on his sleeve. He denies any form of selfless behavior. Pyle is the naive American who is openhearted and believes he acts for the good of others. Yet both men cause great damage because they care about others. They are caught up in the evil that Fowler thinks he can avoid and that Pyle thinks he can remove. The political and moral divide between Fowler and Pyle is not as great as Fowler has supposed. His narrative ironically binds him to Pyleââ¬âa fate Fowler has consistently tried to avoid. The novel dramatizes Fowlerââ¬â¢s fate in the scene where he refuses to call Pyle by his first name. He also refuses to let Pyle call him Tom and insists on being called Thomas. No formalities can really separate the two men however. Fowlerââ¬â¢s own narrative shows them to strongly connected. The Quiet American is concerned with the effect the superpowers have when they intervene in the politics of the developing nations, in this case, Vietnam during the last days of French colonial rule. Greene himself is in an interesting position in that England, once a major colonial power, has increasingly surrendered that position to the United States since World War II. This weakened position makes Greene, like Fowler, something of an observer of the more active Americans. Fowler observes the covert actions of Pyle and finds them wrong. He thinks Americans are politically naive, dangerously idealistic, and too willing to hurt other people if they get in the way of their political goals. Greene has been accused of being anti-American but the novel and Fowlers judgment of Pyle were obviously very relevant. The novel was especially popular during the war in Vietnam, when many Americans came to share Fowlers opinions. Although the war and the controversies surrounding it still plague the memories of many Americans, the war and the novel itself are not quite so topical as they were in the 1960s and early 1970s. Still it might be worth stressing that the novel was written well before America became deeply involved in Vietnam. In fact, America is now involved as a ââ¬Å"Third Forceâ⬠in Iraq, where the political concerns of the novel are still quite applicable.
Thursday, November 28, 2019
From Text A, The Father In The Family Has Two Opposite Personality. He
From text A, the father in the family has two opposite personality. He is a cheerful person in his workplace however when come to home, he misbehaves. In line 21, ?he was like the scotch in the smooth, happy machine of the home?. In line 51, ?They united with in the work? His son felled that his father does even bothers about him and the family. However in line 25, stated that he would dearly have liked the children to talk to him, but they could not. From text C, the problem occurs from the son, Albert. He is a kind like to show a rebellion to his mother. He feels that he own his freedom. He can do whatever wants. Just because he is the only person his mother life, she tend to chow how much she care about him. In my opinion, Albert may be overshadowed by his late father whom I feel behave strictly and controlling him too much. Since his father has passed away, he believes that now it is the payback time.
Monday, November 25, 2019
How successful was Peels Ministry 1841-1846 Essays
How successful was Peels Ministry 1841-1846 Essays How successful was Peels Ministry 1841-1846 Essay How successful was Peels Ministry 1841-1846 Essay Peels ministry essentially benefited the nation as a whole, which would suggest that Peels ministry was very successful. However, in doing so he split the party we had worked so hard to bring together. Therefore when considering whether his ministry was a success or not it has to be assessed whether a ministry has to primarily look after the partys interests or the nations. Most historians including the likes of Donald Read take the view that the nations interests should be the priority, and this is why Peels ministry is considered successful. Despite diluting some of the Traditional Tory views which agitated the landowners, and eventually splitting the party through the Repeal of the Corn Laws in 1846 Peels ministry improved the living and working conditions of the average person. He managed to do this most importantly through his financial reforms which were very successful, as well as his social reforms. Peel aimed to be fairer to the poor, although at some expense of the landowners. The decline of radical groups within Britain though out Peels ministry marked its success, and although he did carry out a number of unsuccessful polices in Ireland, he critically prevented them from leaving the Union through good work in 1843. Peels financial reforms were the most important reasons for its success despite their unpopularity in some sections of the party. In 1941 he inherited à £7million of debt from the Whig government before him, but through a selection of significant reforms, most notably the 1842 Budget he was able to boast a à £5 million surplus by the end of 1865. Much of the financial reform that Peels ministry passed could be considered as social reform too, which was very important in improving the conditions for people in Britain. The 1842 Budget aimed to appeal to the rich through a sense of justice and self preservation, at the same time as showing the poor there was a fairer system. Peel boldly reintroduced income tax for 3years which affected those wi th annual incomes of à £150 or more. This was hugely unpopular with the landowners, and therefore a great section of his parties support base however, it was greatly successful and despite being expected to raise 3-4 million a year it actually raised à £5million. The removal of duties on 600 goods, and the reduction on 500 more, considerably reduced the cost of living for the majority of the British population. It was also a step towards free trade, an issue which Peel had been greatly influenced by a free trade philosopher, Adam Smith, who argued the fewer restrictions, the better the economy would become. Peel also passed reform in 1844 with the Bank Charter Act creating a more efficient banking system on which the government could trust and rely, as well as the Companies Act which monitored companys progress and improved the nations financial health. Some historians have accused Peel about being too focused on his financial policies, however throughout his ministry he made genuine attempts to improve the conditions for workers, especially in mines and factories. Peel had always shown sympathy for the less-well off, and even early in his career in 1829 he had shown this through some of his reforms. His government set up of the National Relief Fund in 1841 to investigate the conditions for workers in growing industrial cities in addition to the pressure from leading figures like Lord Ashley, which prompted social reform. The reforms he made were not really radical, but were common sense and made the working environment for workers safer, reducing fatalities where death was frequent. The 1842 Mines Act forbade women and children under 10 to work underground, and the 1844 Factory Act which was largely driven by Peels home secretary, Sir James Graham, limited the hours children under 13 could work, and recommended safety improvements. The reform was successful in improving working conditions for some, and it reduced the death rates at work places as environments became safer. However, this did come at a cost in that it frustrated many Tory supporters as the efficiency of their industry was being compromised. Peels ministry also introduced The Railway Act in 1844 aimed to regulate the activities of railways to safeguard passengers interests, and called for a parliamentary train to run once a day which stopped at every station on the line. The improvement in living conditions for most people, and therefore success of Peels ministry, was marked by the decline of radical groups such as the chartists. One historian, Donald Read said Peel was: The hero of equally the newly enfranchised, the middle classes and of the unenfranchised property less masses. Peels ministry really benefited the poor and the middle class, as it narrowed the gap in some way between them, and the monopolising landowners through the introduction of fairer policies. The popularity of such groups like chartists depended on economic crisis which Peel effectively contained through timely and accommodating reform which kept the majority happy. Peel vitally saw that although it was important to maintain traditional Tory values to retain the support of much of his party, they were holding the party back in many ways, most of them unfairly and unnecessary. He worked around this by successfully diluting traditional policies to appeal to a wider number of people. Peels political career was closely intertwined with Ireland and OConnells career, an Irish political figurehead. Peels policies towards Ireland were on a whole relatively unsuccessful, and his attempts to win over moderate Catholic opinion while retaining the key features of the established church greatly failed, in some cases actually angering both Protestants and Catholics. The Irish Colleges Bill in 1844 which Peel hoped would bridge gaps between the Protestants and Catholics in Ireland ironically did the opposite. However, Peels policies to Ireland were hindered by Protestant Peers, and the self-interested landowners constantly slowing and refusing most of it, in the case of the Maynooth Grant in 1845, although it won over some catholic opinion it was passed too late, and just increased tension within the Conservative Party between Tory Ultras, and Peel. Despite Peels overall disappointment on the issue of Ireland, in 1843 he crucially took firm action to prevent the Repeal of the Union Act 1800, which made Ireland part of Britain. OConnell tried to use mass agitation to force the repeal as it had worked for him in 1829. However, when Peel recognised the seriousness of the threat from the Repeal Organisation as it became known, he made it clear he would be prepared to use force to uphold the act. Peel also took more decisive action in 1843 by passing a Coercion Act which banned OConnells huge meeting at Clontarf, and arresting him for conspiracy. This approach was successful in keeping Ireland in the Union, one of the many problems Peels ministry faced, although it did come at some cost as Irish nationalists now rejected OConnells constitutional approach and resulted to violence to bring about change. Peel has been named a betrayer of his party by some historians such as the modern historian Eric Evans who said Peel: Either ignored his followers sensibilities or bludgeoned them into submission. However, as Prime Minister of Britain he was using his skills as a leader and administrator not only to represent and benefit a small select group, but fairly to the whole nation. A successful ministry has to primarily address its nation and not its partys interests; this is what Peels ministry did. Although Peel had the backing of many Ultra Tories to get into government, Peel had very much created a new conservative party that stated they would reform if and when they saw necessary. In 1846 Peel saw the Corn Laws as the last major obstacle of achieving free trade. He believed that by repealing the Corn Laws British industry would become more competitive, and exports would be increased. He knew that he risked the unity of his part, and his own career but he believed that agricultural protection was no longer necessary or fair. They were in place for political and not economic reasons, and despite the Conservative partys negative view towards reform, Peel believed it would boost manufacturing, and lower prices for living, as well as demonstrate he was in touch with the needs of ordinary people. Peel did ultimately split the party he had created by forcing through the Repeal of the Corn Laws in 1846 however, he did it in the nations best interest, Britains economic prosperity for the next 30 years bearing witness to this. Some may argue that by splitting his party and not abiding to polices he was elected on, most notably he had promised not to repeal the Corn Laws, Peels ministry was a failure. He caused such a split in the party that it took around 30years for the conservative party to really find its feet again. Peels policy to winning over moderate opinion had been hugely successful nationally except it had come at a cost. Peels ministry from 1841 can be considered a success despite it concluding in the split of the Conservative party in 1846. This is because on a whole, the nation benefited greatly from moderate reform which caused working conditions to improve and the cost of living to be reduced, which improved living conditions. A greater deal of economic stability was reached as well as the national debt being eradicated. The reduction in radical activity emphasised the fact that conditions were improving in Britain at this time. As the average man of Britain benefited from Peels ministry, it came at a cost to the landowners and Tory Ultras who were a considerable part of the Conservative partys support base. In a sense Peels ministry was unsuccessful in terms of the negative impact it had on the Conservative party, and the tension that it created which peaked in 1846 as the Corn Laws were repealed and the Conservative party split. However, Peels ministry was prevailingly successful, in comparison to its party failure, as it greatly benefited the nation as a whole, most importantly though its financial reform, and also reaching its climax in 1846 with the Repeal of the Corn Laws.
Thursday, November 21, 2019
Salvador Dali and Pablo Picasso Term Paper Example | Topics and Well Written Essays - 2750 words
Salvador Dali and Pablo Picasso - Term Paper Example The essay "Salvador Dali and Pablo Picasso" discovers the Salvador Dali's and Pablo Picasso's art. Both Salvador Dali and Pablo Picasso are well-known Spanish painters. They have not only accomplished a number of masterpieces that gained worldwide acceptance but they also received considerable criticisms that make them more famous. Dali, whose works usually deal with surrealism, is noted for absurdity. In his painting, Soft Construction with Boiled Beans, Dali presents an image of a monster tearing itself apart. This oil painting is usually referred to as a premonition of the Spanish Civil War because Dali made it six months before the war broke out. The painting, considered to be a surrealist painting, measures 100 cm x 99cm., and is currently housed in Philadelphia Art Museum of Art. Dali is famous for surrealism in his works. Convincingly the surreal nature of Daliââ¬â¢s images has led him to fame, but according to Saladyga, his ââ¬Å"eccentric manner and attention-grabbing pu blic actions sometimes drew more attention than his artworkâ⬠(15). Specifically, Daliââ¬â¢s Soft Construction with Boiled Beans has gained him both positive and negative commentaries. Nevertheless, the subject, style, and symbols that he used make the painting a real masterpiece as it evokes the cultural and historical experience of the Spanish. Pablo Picasso is likewise a world-renowned Spanish painter and is even more famous and respected than Dali in the visual art scene. He is well-known for cubism, a style he himself made popular. With his craftsmanship and hard work, Picasso can be considered the most prolific artist not only of his time but even of all times. Throughout his lifetime, he produced a total of 6,000 paintings, 165 of which he painted in 1969 alone, when he was 88 years old (Whitman 53). He started painting at two years old and produced sketches, sculptures, lithography, and even plays before he died at 92 (Whitman 53). Guernica is one of his masterpieces . This oil painting, which measures 11à feet tall and 25.6 feet wide, was painted in 1937, two days after the bombing of Guernica. To date, it reminds the Spanish of the bombing of the Basque town of Guernica by some German bombers who were allegedly supporters of General Franco during the Spanish Civil War. At present, the painting is housed in Museo Reina Sofia, Madrid but a number of replications including the one in the United Nations have been on display worldwide. Both paintings mentioned reflect the paintersââ¬â¢ view of the Spanish Civil War. According to Beevor (19), the war started on July 17, 1936 and lasted until April 1, 1939. It began after the proclamation of opposition by some Spanish generals led by Jose Sanjurjo against the leadership of the then President Manuel Azana. The group of generals were supported by a number of groups, including the Spanish Confederation of the Autonomous Right, Carlists, and Fascist Falange, which were strong political parties at th e time. Hence, the move resulted in political and military warfare. Later, the government obtained support from Germany, Italy and Portugal, thus heightening the conflict especially with the bombing of Guernica, Basque Country on April 26, 1937 by German and Italian troops. Guernica is said to be a marketplace, thus many people were hurt during the bombing, especially since that day was a market day.
Wednesday, November 20, 2019
Comparison & Contrast on Romanticism and Realism literary movements Essay
Comparison & Contrast on Romanticism and Realism literary movements - Essay Example Consequently, as industrial revolution progressed, these poor working conditions raised a lot of concerns and people started to advocate for changes. Artists and writers were amongst the people who were championing for the changes (Dahiya 4). They responded to these conditions in many different ways and as a result, romanticism and realism artistic movements emerged. Romanticism movement originated from Europe in the mid of the 18th century and was concerned with emotions and imagination (Morris, 169). It opposed aristocratic social and political ideologies of the age of enlightenment and the scientific rationalization of nature (Mendelowitz 153). Romanticism was highly centered on visual arts, literature and music but had greater impacts education and natural history (Morris, 49). During the 18th century, romanticism was common and popular (Reynolds 81). However, in the second half of 19th century it lost its popularity and was overtaken by realism movement. Realism movement was bas ed on real life and unlike their immediate predecessors (romantics), the practitioners of realism sought to portray real life, both good and bad. They were far more interested in science and in civilization, and far less interested in nature and the occult. Realists, like Romantics, were very moral writers, but moral causes changed with the times as new conditions dictated new issues (Richardson 56). Both romanticism and realism gathered a lot of fame during the era of industrial revolution. However, it was realism that was more popular from mid 1800s on. Romanticism only dominated from mid 1700s to the mid 1800s (Dahiya 4). Romanticism artists and writers put passion and emotions in their work. The works created by these writers and artists often dealt with themes that bring hope and inspiration or reflected natureââ¬â¢s beauty (Ferber 15). The works were always based on nationalism, spirituality and mankind. The works of the romantic artists gave the people an escape from the p roblems and challenges that they faced during the industrial revolution (Reynolds 111). The works of literature that are usually associated with this movement are the poems of William Wordsworth and William Blake. Other works include Mary Shelleyââ¬â¢s novel, Frankenstein, which was a story about a scientist who tried to create human but created a monster, Alexandre Dumasââ¬â¢s work, The Three Musketeers and Victor Hugoââ¬â¢s novel, The Hunchback of Notre Dame (Richardson 67). The works of realists were based on real life. The art and literature developed or made by realists exposed life as it was. They clearly pointed out the difficult living and working conditions that were eminent during the era of industrial revolution. Most of the writers and artists of realism were activists who used their works to reveal the evils of society in the hope that they would be reformed. Realists had hopes that their works would bring inspiration to the politicians and other people in powe r thus enable them make lasting changes in living and working conditions (Herman 11). The realists were also referred to as social critics since they used to criticize the society. In US, the realists were referred to as muckrakers since they raked the muck that was in the society. The criticism of the realist was always on specific cause such as child labor, living conditions and working conditions in industries. Realistsââ¬â¢ literature writers created factious works but their plots were real. The most known realist author is Charles dickens who was a British
Monday, November 18, 2019
Political Economy Lectures Essay Example | Topics and Well Written Essays - 750 words
Political Economy Lectures - Essay Example The Council on American Islamic Relations (CAIR) is an organization whose main aim is to advocate for the rights of Muslims in North America. It can be said that it represents all Muslim who live in North America. Its headquarters are situated in Washington D.C, and it has offices in at least twenty states and in Canada, and advocating for mutual understanding and justice is its vision. Its mission is to empower all American Muslims,, protect their rights, encourage dialogue and promoting understanding and justice through building coalitions. The talk informed us of what the Council on American-Islam Relations (CAIR) does in its day to day operations. They include, protecting the rights of American Muslims during questioning by the Federal Bureau of Investigations (FBI) and other law enforcement agencies, fighting for the rights of Muslims who have been subjected to employment discrimination and even those who have been terminated wrongfully. It also stopped unlawful seizers of prope rty by law enforcement and also advocates for equal student rights in schools and other learning institutions. The talks also sort to educate us on how people stereotype Muslims in America. ... Most people picked the first two photographs because the people in the photographs had dressed in a manner suggesting they were Muslims. The speaker showed how people were wrong by telling them that even the blond lady in one of the photographs was indeed a Muslim. The talk also informed us on the demography associated with Muslims in America. The speaker pointed out that Democrat accepted Muslim Americans more than Republicans. For instance the speaker pointed out that in the 2008 presidential elections seventy nine percent of Muslims living in America voted for the candidate from the Democratic Party. It was also pointed out that the Republican Party should advocate for the rights of American Muslim since they hold a significant percentage of the national vote. The theme of the talk was generally tolerance towards Muslims in America. The speaker aimed at showing how and why Muslims living in America are subjected to a lot of torment due to the issue of terrorism. He showed this by identifying the rise of Anti-Islam movements and Islam phobia in the United States of America. Islamophobia is an extreme fear of and hatred of Muslims. After the terrorist attack on the twin towers in September 11th 2001, hatred and fear of Muslim in America rose. Since then, Muslims in America have been put to discrimination and violence. ` After the talk, it was clear how Muslims in America have been oppressed. The talk made me realize that the opinion I had about Muslims in general was just a stereotype and that it was wrong. I came to understand what Muslims go through and how their rights are violated. I would encourage the Council on American-Islam Relation (CAIR) to continue with their good work in lobbying for the rights of
Friday, November 15, 2019
Plant DCL Proteins
Plant DCL Proteins Abstract Dicer, a double-stranded RNA (dsRNA)-specific endoribonuclease, plays an essential role in triggering both transcriptional and post-transcriptional gene silencing in eukaryotes by cleaving dsRNAs or single-stranded RNAs bearing stem-loop structures such as microRNA precursor transcripts into 21- to 24-nt small RNAs. Unlike animals, plants have evolved to utilize at least four Dicer-like (DCL) proteins. Extensive genetic studies have revealed that each DCL protein participates in a specific gene silencing pathway, with some redundancy. However, a mechanistic understanding of how the specific action of each DCL protein is regulated in its respective pathway is still in its infancy due to the limited number of biochemical studies on plant DCL proteins. In this review, we summarize and discuss the biochemical properties of plant DCL proteins revealed by studies using highly purified recombinant proteins, crude extracts, and immunoprecipitates. With help from co-factor proteins and an ATP ase/DExH-box RNA-helicase domain, the microRNA-producing enzyme DCL1 recognizes bulges and terminal loop structures in its substrate transcripts to ensure accurate and efficient processing. DCL4 prefers long dsRNA substrates and requires the dsRNA-binding protein DRB4 for its activity. The short-dsRNA preference of DCL3 is well suited for short-RNA transcription and subsequent dsRNA formation by coupling between a plant-specific DNA-dependent RNA-polymerase IV and RNA-dependent RNA-polymerase 2 in the transcriptional gene silencing pathway. Inorganic phosphate also seems to play a role in differential regulation of DCL3 and DCL4 activities. Further development of biochemical approaches will be necessary for better understanding of how plant DCL proteins are fine-tuned in each small RNA biogenesis pathway under various physiological conditions. Introduction RNA silencing, also known as RNA interference (RNAi), is one of the fundamental molecular mechanisms conserved in most eukaryotes to regulate gene expression both transcriptionally and post-transcriptionally. In both situations, what triggers the RNA silencing pathway is a small RNA molecule, 21 to 24 nt in length, called small interfering RNA (siRNA) or microRNA (miRNA) depending on its origin and the downstream pathways involved. The class 3 endoribonuclease (RNase) III enzymes known as Dicer are responsible for producing siRNA from longer double-stranded RNAs (dsRNAs) and miRNA from single-stranded RNAs with internal stem-loop structuresÃâà by a dsRNA-specific endoribonuclease. Therefore, the activity and regulation of Dicer-family proteins in a cell are vital to many biological processes requiring flexible adjustments at the level of gene expression, such as development, organogenesis, the circadian rhythm, biotic and abiotic stress responses, and defense against viruses an d transposons. Biochemical characterization of Dicers in animals The Dicer family is a unique class of RNase III enzymes due to the presence of an ATPase/DExD/H-box helicase domain at the N-terminus, a Piwi/Argonaute/Zwille (PAZ) domain in the middle and dual RNase III domains followed by one or two dsRNA-binding domains in the C-terminal half (exception: Giardia intestinalis) (Figure 1) (Bernstein et al. 2001). In general, the helicase domain serves as a protein-protein interaction surface recruiting co-factor regulatory proteins (Lee et al. 2006; Ma et al. 2008; Ye et al. 2007). It also utilizes ATP hydrolysis to achieve processive cleavage of the long dsRNA substrate (Cenik et al. 2011; Welker et al. 2010). The PAZ domain contains a conserved pocket for recognizing the terminus of the dsRNA substrate, and the distance between PAZ and the RNase III catalytic center determines the product sizes (MacRae et al. 2007; MacRae et al. 2006). Each of the two RNase III domains cuts one of the dsRNA strands, leaving a characteristic 2-nt overhang at 3-end of the product (Elbashir et al. 2001; Takeshita et al. 2007; Zhang et al. 2004). The C-terminal dsRNA-binding domains (dsRBDs) serve as a protein-protein interaction interface and nuclear localization signals, in addition to having dsRNA-binding function (Doyle et al. 2013; Hiraguri et al. 2005; Wostenberg et al. 2012). The specific functionality of each domain differs depending on the Dicer protein. Since the first demonstration of in vitro small RNA-producing activity of Dicer in the fruit fly Drosophila melanogaster (Bernstein et al. 2001), its biochemical properties and regulatory machinery have been extensively studied in humans, D. melanogaster and Caenorhabditis elegans. In humans, there is only one Dicer-family protein (hDicer), which cleaves short-hairpin pre-miRNAs produced by Drosha and dsRNA substrates into 20- to 22-nt small RNAs in an ATP-independent manner (Myers et al. 2003; Provost et al. 2002; Zhang et al. 2002). The cleavage activity requires a divalent metal cation such as Mg2+, Co2+ or Mn2+, and recognizes mainly the 5-end of the substrate to dictate the product length (Park et al. 2011). This 5-counting rule is reliant on the conserved 3-pocket motif within the PAZ domain and the 5-pocket motif, which is less conserved in Dicers of other eukaryotes. The binding of Dicer to a dsRNA substrate and its cleavage are uncoupled, because Dicer can bind to dsRNA with out Mg2+ or under low temperature (Provost et al. 2002; Zhang et al. 2002). The helicase domain of hDicer has an autoinhibitory function (Ma et al. 2008). In line with this, the activity of recombinant full-length hDicer protein can be improved under limited proteolytic conditions (Zhang et al. 2002). hDicer is responsible for both siRNA and miRNA production, and co-factor dsRNA-binding proteins TRBP and PACT dictate hDicer function in the two distinct small RNA production pathways (Chendrimada et al. 2005; Haase et al. 2005; Kok et al. 2007; Lee et al. 2013; Lee et al. 2006). In particular, the hDicer complex containing PACT disfavors siRNA precursor dsRNA and shows different cleavage patterns on the same pre-miRNA substrate than the hDicer-TRBP complex (Lee et al. 2013). The interaction with TRBP occurs through the hDicer helicase domain, and stimulates the hDicers catalytic activity. (Ma et al. 2008). Similarly, it has been reported that the C. elegans Dcr-1 interacts with a dsRNA-binding protein RDE-4 which enhances the Dicer activity toward long dsRNA substrates in siRNA production, while RDE-4 is apparently dispensable in miRNA production pathway (Parker et al. 2006; Parker et al. 2008; Tabara et al. 2002). D. melanogaster has two Dicer proteins, Dcr-1 and Dcr-2, which produce miRNA and siRNA, respectively (Lee et al. 2004; Miyoshi et al. 2010). Dcr-1 alone can process dsRNA into siRNA in vitro, but its interaction with the dsRNA-binding protein Loquacious isoform PB (Loqs-PB) confers pre-miRNA substrate specificity to the Dcr-1-Loqs complex by suppressing cleavage of long perfect dsRNAs and enhancing pre-miRNA processing activity (Saito et al. 2005; Zhou et al. 2009). Dcr-2 interacts with Loqs isoform PD and another dsRNA-binding protein, R2D2, in the siRNA production pathway (Liu et al. 2003; Liu et al. 2006; Miyoshi et al. 2010; Zhou et al. 2009). Dcr-2 alone is also capable of cleaving a pre-miRNA precursor in an ATP-independent manner, but R2D2 significantly suppresses Dcr-2 activity toward pre-miRNA, whereas Loqs-PD enhances the cleavage activity of Dcr-2 toward long perfect dsRNA precursors by boosting its affinity to the substrate (Cenik et al. 2011; Miyoshi et al. 2010). The pr ocessive processing of long dsRNA substrates by Dcr-2 depends on ATP hydrolysis by its ATPase/helicase domain, implying that one of the functions of the helicase domain is to allow Dcr-2 to produce multiple siRNAs from a single long dsRNA molecule before it dissociates from the substrate (Cenik et al. 2011). Such differential regulation of Dicer activity through specific interaction with co-factor dsRNA-binding proteins in distinct pathways is commonly found in most of the systems studied, including plants. DCL proteins in plants Plant genomes contain at least four distinct classes of DCL family proteins (DCL1-4). Like their animal counterparts, each class of DCL has evolved to participate in its primary pathway (Figure 2), but the three siRNA-producing DCLs (DCL2-4) function redundantly as well, because defects in one class of DCL can be compensated for by other classes in some cases (Gasciolli et al. 2005; Mukherjee et al. 2013; Xie et al. 2004). Because DCL1 is the only Dicer protein that produces most 21-nt miRNAs (Kurihara and Watanabe 2004; Reinhart et al. 2002), knockout mutants of DCL1 are embryonic lethal (Schauer et al. 2002). DCL4 is the major producer of 21-nt antiviral siRNA and endogenous siRNAs such as trans-acting siRNA and phased siRNAs (phasiRNA) (Bouche et al. 2006; Gasciolli et al. 2005; Mukherjee et al. 2013; Qu et al. 2008; Xie et al. 2005; Yoshikawa et al. 2005). DCL2 can compensate for the loss of DCL4 (Bouche et al. 2006; Gasciolli et al. 2005; Parent et al. 2015), although its major function remains unclear. DCL3 mainly produces 24-nt repeat-associated siRNAs derived from transposons and DNA repetitive elements, and participates in transcriptional gene silencing (TGS) through RNA-dependent DNA methylation, suppressing proliferation of these elements (Henderson et al. 2006; Pontes et al. 2006; Xie et al. 2004). In addition to the four classes of DCLs, monocots have another distinct class of Dicer, DCL5 (also known as DCL3b) (Margis et al. 2006). DCL5 is specifically expressed in developing panicles and is responsible for 24-nt reproductive phasiRNAs, although the biological significance of a reproductive-organ-specific 24-nt phasiRNA pathway mediated by this specific Dicer remains to be elucidated (Borges and Martienssen 2015; Fei et al. 2013; Kapoor et al. 2008; Song et al. 2012). This pathway might be analogous to the Dicer-independent PIWI-interacting RNA (piRNA) pathway in vertebrates, which suppresses transposons and other genes specifically in germlines (H irakata and Siomi 2016). Both forward and reverse genetics and physiological studies have successfully dissected the major RNA silencing pathways and allowed identification of the function of DCL genes in each pathway in plants. However, investigations on the molecular and enzymatic characteristics underlying the functional diversification and specificity of the DCL proteins are still in their infancy. Detection of DCL activity in crude extracts of various plants Biochemical characterization of plant Dicer activity was first demonstrated in wheat germ extract (monocot) and cauliflower extract (dicot), which contain multiple DCL activities producing ~21 nt and ~24 nt small RNAs with 2-nt 3-overhangs in the double-stranded form (Tang et al. 2003). These activities are weaker in the absence of ATP, consistent with characteristics of Dicer family proteins from Drosophila and C. elegans. Long dsRNA competitors effectively suppress both activities in wheat germ extract. The 24-nt small RNA producing activity was inhibited by 25-nt synthetic siRNA duplexes, whereas 21-nt small RNA production was unaffected by 21-nt synthetic siRNA duplex competitors, suggesting that two different enzymes with active sites that have distinct size-dependent binding properties are in the wheat germ extract (Tang et al. 2003). A recent study on wheat germ extract characterized these activities in further detail, revealing (1) that the 21-nt activity could be found in a much larger (~950 kDa) complex than the 24-nt activity, which had maximum activity in an approximately 450 kDa complex; and (2) the biochemical properties associated with the activities, such as divalent cation and NTP requirements, optimum NaCl concentration, temperature, and pH, and substrate length dependence (Shivaprasad et al. 2015). The identities of the DCL enzymes responsible for these activities in the wheat germ extract remain to be identified. A better understanding of the biochemical characteristics of individual plant Dicer proteins has come from the model plant Arabidopsis thaliana, which has four DCL proteins: DCL1, DCL2, DCL3 and DCL4 (summarized in Table 1). The first in vitro DCL activity in A. thaliana was demonstrated using a suspension cell lysate, a crude extract of inflorescence tissue, and an immunoaffinity-purified protein complex (Qi et al. 2005). Similar to the previous study using wheat germ extract or cauliflower, extracts from both Arabidopsis cultured cells and inflorescence tissue contained DCL dsRNA-cleaving activity producing 21- and 24-nt small RNAs from 400-bp dsRNA (Qi et al. 2005). The 21-nt producing activity and 24-nt producing activity were found in >660 kDa and ~400 kDa fractions, respectively, suggesting that these Dicers reside in protein complexes composed of multiple co-factors (Qi et al. 2005). In agreement with previous genetic studies showing CARPEL FACTORY/DCL1 is responsible for 21-nt miRNA production in vivo (Kurihara and Watanabe 2004; Reinhart et al. 2002), the 21-nt small RNA producing activity was DCL1 immunoaffinity-purified from inflorescence-derived crude extract by an anti-DCL1 antibody (Qi et al. 2005). The 24-nt activity was associated with anti-DCL3 antibody immunoprecipitate, and the activity was abolished when purified from a dcl3-1 mutant, showing that DCL3 is responsible for the 24-nt activity in Arabidopsis inflorescence extract. The immunoaffinity-purified DCL1 activity required ATP, whereas the activity of the DCL3 immunoprecipitate was ATP-independent (Qi et al. 2005). Interestingly, the dcl1-7 mutation did not abolish the 21-nt small RNA producing activity in the extract or immunoprecipitates, implying that the substitution (P415S) in its N-terminal helicase domain did not alter the enzymes catalytic activity itself (Qi et al. 2005); this study also found that the activity of DCL4 responsible for formation of 21-nt siRNA was present in the inflorescence extract. The presence of DCL4 activity in an Arabidopsis crude extract was demonstrated in later studies using 2-week-old seedlings as the starting material (Fukudome et al. 2011; Nagano et al. 2014), and will be discussed later in this review. In-depth biochemical characterization of DCL1, a microRNA-producing enzyme in plantsà DCL1 activity requires DRB1/HYL1 and SERRATE for accurate processing of the miRNA precursor Both in wheat germ and Arabidopsis extracts, DCL activities are associated with size fractions larger than DCL monomeric form, implying that these DCLs form functional protein complexes composed of multiple co-factors in vivo. As summarized in an earlier section, such interactions between a Dicer and a co-factor protein are commonly found in mammals, nematodes and insects. One of the most characterized classes of co-factor proteins is a dsRNA-binding protein (dsRBP) harboring multiple dsRNA-binding domains or motifs. The A. thaliana genome encodes five dsRNA-binding (DRB) family proteins: DRB1/HYL1, DRB2 DRB3, DRB4, and DRB5. Multiple genetic and biochemical studies have demonstrated two specific interactions between DCLs and DRBs in A. thaliana: DCL1-DRB1/HYL1 and DCL4-DRB4 (Han et al. 2004; Hiraguri et al. 2005; Kurihara et al. 2006; Nakazawa et al. 2007). Arabidopsis DCL1, DRB1/HYL1, and another co-factor, SERRATE (SE), constitute an essential microRNA production pathway in vivo (Han et al. 2004; Lobbes et al. 2006). Unlike animals, which utilize two distinct RNase III enzymes, Drosha and Dicer, for the first and second cleavage of microRNA precursors, plants do not employ Drosha. Therefore, the DCL1-complex is responsible for the processing of both primary and precursor miRNA substrates. The detailed molecular machinery of the dual miRNA processing mediated by DCL1 and the co-factor proteins have been extensively studied biochemically using highly purified recombinant proteins produced in heterologous systems (summarized in Figure 3). One of the systems utilizes baculovirus-mediated recombinant protein production in Sf21 insect cells, followed by two-step affinity purification (Dong et al. 2008). The highly purified recombinant DCL1 protein alone could process a 94-bp dsRNA substrate with a 2-nt 3-overhang into 21-nt small RNA in an ATP/Mg2+ dependent manner. The optimum NaCl concentration for the activity was 25-50 mM, and a NaCl concentration higher than 100 mM severely impaired the activity (Dong et al. 2008). While the recombinant DCL1 protein alone could produce 21-nt small RNA from both primary and precursor miRNA (pri-/pre-miR167b) substrates in vitro, DRB1/HYL1 and SE recombinant proteins co-incubated in the same reaction mixtures significantly increased both yield and accuracy of the processing (Dong et al. 2008). Without these co-factors, more than 80% of 21-nt small RNA products from the DCL1-alone reaction were due to incorrect processing from the end of the primary miRNA substrate, whereas the processing mediated by the DCL1-DRB1/HYL1-SE complex produced accurate 21-nt products with a sequence identical to miR167b/miR167b*, amounting for up to 81% of the products (Dong et al. 2008). This demonstrated that accurate processing of miRNA precursors by DCL1 requires the co-factors DRB1/HYL1 and SE. Cons istent with a previous study, the interaction between DCL1-DRB1/HYL1 through the second dsRNA-binding motif of DCL1 is important for the precise processing of pri-miRNA in A. thaliana (Dong et al. 2008; Kurihara et al. 2006). Also, using highly purified recombinant proteins and surface plasmon resonance analysis, it has been suggested that DCL1 changes its structural conformation when it binds RNA and exposes more binding sites for SE (Iwata et al. 2013). Binding to substrate dsRNA or miRNA precursors might be an important regulatory step for DCL1 dicing activity, as its dsRNA-binding domains exhibit the strongest binding to dsRNA among the four Arabidopsis DCLs (Hiraguri et al. 2005). ATPase/DExH-box RNA-helicase domain of DCL1 suppresses its dicing activity, confers ATP dependence, and influences processing accuracy In addition to its RNase III and dsRNA-binding domains, the helicase domain of DCL1 plays a significant role in regulating its dicing activity. Two independent forward genetic studies have identified two dcl1 mutant alleles, dcl1-13 (E395K) and dcl1-20 (R363K), as hyl1 suppressors, and the amino acid substitutions of both alleles occur within the ATPase/DExH-box RNA-helicase domain. These dcl1 mutations partially rescue the accumulation of some miRNAs in a hyl1-2 mutant (Liu et al. 2012; Tagami et al. 2009), and dcl1-13 was at least partially able to restore the phenotypic defects of hyl1-2 such as a reduced number of rosette leaves and aÃâà leaf shape (Tagami et al. 2009). Highly purified recombinant DCL1-20 protein exhibited enhanced catalytic activity (Kcat/Km) toward pri-miRNA156a compared to wild-type DCL1 (Liu et al. 2012). Similarly, the helicase domain-deleted DCL1 recombinant protein (DCL1à ¢Ãâ â⬠Helicase) showed higher processing activity in vitro and was no l onger dependent on ATP for its activity toward pri-miRNA156a (Liu et al. 2012), suggesting that the helicase domain of DCL1 might have an autoinhibitory function like that of human Dicer (Ma et al. 2008; Provost et al. 2002). The in vivo miRNA processing imprecision in hyl1-2, however, was not restored by a dcl1-20 mutation, implying that the partial recovery of the hyl1-2 mutant, including miRNA accumulation, was due to the enhanced catalytic activity resulting from the substitution in the helicase domain (Liu et al. 2012). Interestingly, the effect and magnitude of DRB1/HYL1 and DCL1 helicase domain seem to vary among miRNA precursors. For example, the in vivo processing accuracy of miR156a is much more severely affected by hyl1-2 mutation than miR166b is (Liu et al. 2012). pri-miR156a is processed from the loop-proximal site to the loop-distal base in vitro (Liu et al. 2012), which is considered unusual for plant miRNAs (Addo-Quaye et al. 2009; Mateos et al. 2010). Accurate processing of pri-miRNA166b by native DCL1 is largely dependent on the presence of ATP, and processing by DCL1à ¢Ãâ â⬠Helicase is less accurate than that of native DCL1 (Liu et al. 2012). In contrast to miR156a, the processi ng precision of which is markedly affected by hyl1-2, that of miR166b was much more impaired by dcl1-20 mutation than hyl1-2 (Liu et al. 2012). Also, the effect of the other helicase mutant allele, dcl1-13, on miRNA production was shown to depend on the presence or absence of DRB1/HYL1 in vivo (Tagami et al. 2009). These observations indicate that efficient processing of different miRNA precursors by DCL1 have different reliance upon DRB1/HYL1 and DCL1helicase domain that potentially depends on structural determinants of the miRNA precursors. Structural determinants for efficient and accurate processing of miRNA precursors by DCL1 Primary transcripts of miRNA (pri-miRNA) have a characteristic secondary structure: a loop-distal stem (lower stem), a miRNA duplex, a loop-proximal stem (upper stem) and a terminal loop (Figure 3). Typical miRNA maturation from these precursors requires at least two cleavages occurring at the lower and upper stems. In animals, the single-stranded base region of the loop-distal stem is recognized by the dsRNA-binding protein DGCR8, which guides the processing center of Drosha to the correct position, which is 11 nt from the base of the stem (Han et al. 2006). However, this distance-from-base rule is not sufficient for plants because the length of the loop-distal stem of plant pri-miRNAs is highly variable (Song et al. 2010). Several structural features of pri-miRNAs that influence the activity, binding position and directionality of the processing by DCL1 have been elucidated genetically and biochemically (Figure 3a, b). One structural determinant lies within the loop-distal stem of pri-miRNA. For the first cleavage at the loop-distal stem, bulges and unpaired regions play a major role in the efficiency of miRNA processing. Mutant pri-miRNAs with closed bulges were processed at the correct position, but resulted in the accumulation of unprocessed pre-miRNAs in vivo, indicating that the rate of subsequent processing at the loop-proximal stem was impaired (Song et al. 2010). In pri-miR171a, which has a long loop-distal stem, the first cleavage position was determined by the distance from a relatively unstructured region instead of the base of the stem; the conserved distance from an unstructured region of the lower stem important for miRNA processing was found to be approximately 15 nt (Figure 3a) (Mateos et al. 2010; Song et al. 2010; Werner et al. 2010). The 15-nt rule was essentially reproduced in an in vitro miRNA processing system using highly purified DCL1-DRB1/HYL1-SE recombinant proteins and an artificial pri-miRNA substrate bearing another unstructured region in the elongated lower stem. In addition to the canonical processing, another type of processing occurred at 15 nt from the artificially introduced unstructured region, validating the functionality of the 15-nt rule (Song et al. 2010). The importance of bulges and unpaired regions in the lower stem for processing by DCL1 might explain why some miRNAs with a near-perfect matched stem seem to be DCL4-dependent, rather than DCL1-dependent (Rajagopalan et al. 2006; Song et al. 2010). On the loop-proximal and terminal loop side, a branched terminal loop (BTL) or a large terminal loop was found to be an essential structural factor that may alter directionality of processing by DCL1 and the resultant miRNA-accumulation (Figure 3b). BTL induces abortive processing of pri-miR166c both in vivo and in vitro (Zhu et al. 2013), meaning the first cleavage of the pri-miRNA occurs in the loop-proximal stem as opposed to the normal productive processing beginning in the loop-distal stem. The molecular basis of this bidirectional processing by DCL1 was further investigated using an in vitro system that reconstitutes the DCL1-processing machinery. For this purpose, DCL1, DRB1/HYL1 and SE harboring Agrobacterium tumefaciens were co-infiltrated to Nicotiana benthamiana leaves, and the transiently expressed DCL1-DRB1/HYL1-SE complex was immunoaffinity-purified two days after infiltration (Zhu et al. 2013). The reconstituted DCL1 complex cleaves the substrate pri-miRNA 16-17 nt fro m the unpaired region of the lower stem, supporting previous studies (Mateos et al. 2010; Song et al. 2010; Werner et al. 2010). By disrupting one of the two RNase III domains of DCL1 alternately and using 5- or 3-end labeled pri-miR166c substrates, the bidirectional nature of both productive and abortive processing was demonstrated (Zhu et al. 2013; Figure 3b). The helicase domain of DCL1 fine-tunes the position of both productive and abortive processing by DCL1 in an ATP-dependent manner (Zhu et al. 2013). DCL1à ¢Ãâ â⬠Helicase complex could not abortively process a substrate with BTL. Also, wild-type DCL1 required ATP for abortive processing, but not productive processing, indicating that the ATPase-driven helicase activity is necessary in abortive processing to unwind the structured BTL (Zhu et al. 2013; Figure 3b). In productive processing, the effect of helicase deletion and ATP depletion depend on the distance between the processing site and the bulge in the lower stem. Many potential byproducts of the abortive processing of pri-miRNA precursors with BTL can be found in publically available high-throughput small RNA sequencing data from both Arabidopsis and rice, implying that both substrate structure and the functionality of the ATPase/helicase domain of DCL1 are conserved mechanisms to regulate miRNA biogenesis in higher plan ts (Zhu et al. 2013). Dissecting distinct characteristics of DCL3 and DCL4 activities DCL4 activity requires the dsRNA-binding protein DRB4 In A. thaliana, DCL2, DCL3 and DCL4 are responsible for producing various siRNAs 21-24 nt in length. The dsRNA-cleaving activities of DCL3 and DCL4 can be detected in crude extracts prepared from 2-week-old seedlings (Fukudome et al. 2011). Extracts from wild-type seedlings cleave 500-bp dsRNA substrates into 21-nt and 24-nt small RNAs. In this system, the 21-nt and 24-nt small RNA-producing activities can be attributed to DCL4 and DCL3 respectively, because the dsRNA-cleaving activity of the corresponding size was abolished in each of the single mutants (Fukudome et al. 2011). Also, a mutation in the dsRNA-binding protein DRB4, which interacts with DCL4 (Hiraguri et al. 2005; Nakazawa et al. 2007), abolished DCL4 activity in seedling extracts. The DCL4 activity could be further purified by immunoprecipitation with anti-DCL4 or anti-DRB4 antibodies. The immunoaffinity-purified DCL4 requires Mg2+ and ATP for its activity, and is inhibited by >200 mM NaCl. This property is similar to t hat of recombinant DCL1 protein (Dong et al. 2008). The DCL4 complex immunoprecipitated from the drb4-1 mutant did not show dsRNA-cleaving activity, but the addition of recombinant DRB4 protein to the complex restored the 21-nt producing activity in vitro, showing that DRB4 functions as an essential co-factor for the dsRNA-cleaving activity of DCL4 (Figure 4b). In this system, mutant DRB4 proteins harboring substitutions in the conserved amino acid residues that form a hydrogen bond with the phosphodiester backbone of dsRNA at the dsRNA-binding site (H32A in the first dsRBD and K133A in the second dsRBD of DRB4) lost their ability to interact with dsRNA and DCL4, and did not restore DCL4 activity. The second substitution (K133A) alone impaired its interaction with the C-terminal half of DCL4 containing two RNase III domains and two dsRBDs in a GST pull-down assay using recombinant proteins, but was not sufficient to block restoration of DCL4 activity when added to DCL4 immunopurified from a drb4-1 mutant extract. There might be an add itional interaction surface between DCL4 and DRB4 involving dsRBD1 of DRB4 and the N-terminal half of DCL4, which contains an ATPase/DExH-box RNA-helicase domain and an RNA-binding domain (formerly known as domain of unknown function DUF283; Figure 1), as their specific interaction was reported in vitro (Qin et al. 2010). Short dsRNA preference of DCL3 activity orchestrates 24-nt siRNA biogenesis in TGS pathway Crude extracts from 2-week-old seedlings have also been used to characterize substrate specificity of DCL3 and DCL4. Consistent with the long dsRNA preference of Drosophila Dcr1 (Bernstein et al. 2001), DCL4 preferentially cleaves longer dsRNA substrates, and is less efficient in producing 21-nt siRNAs when the substrate is shorter than 50 nt (Nagano et al. 2014). On the other hand, DCL3 activity, producing 24-nt siRNAs, favors shorter substrates such as 30 nt and 37 nt dsRNA with a 1-nt or 2-nt 3-overhang (Nagano et al. 2014). It also favors substrate dsRNA with 5-adenosine or uridine. The 24-nt small RNA produced by DCL3 has a 2-nt 3-overhang, and the cleavage follows the 5-counting rule proposed for human Dicer (Park et al. 2011). DCL3 is not reliant on ATP hydrolysis for activity, as it can still process the short dsRNA substrate in the presence of a non-hydrolyzable ATP analog, adenosine 5-O-(3-thio)triphosphate (Nagano et al. 2014). Unlike DCL4, which targets long dsRNAs such a s RDR6-dependent TAS dsRNAs or exogenous viral dsRNAs in vivo (Bouche et al. 2006; Dunoyer et al. 2005; Qu et al. 2008; Yoshikawa et al. 2005), DCL3 may not need to perform a processive cleavage, which requires ATP hydrolysis, because the length of its targets allows only a single cut (Figure 4a). The DCL3 preference for short dsRNA substrate is consistent with the one precursor, one siRNA model for RNA polymerase IV (Pol IV)-dependent 24-nt siRNA biogenesis (Blevins et al. 2015; Zhai et al. 2015). In this model, a remarkably short (30- to 40-nt) transcript with 5-adenosine is produced by Pol IV and is simultaneously converted into double-stranded form by an RNA-dependent RNA polymerase, RDR2. The short dsRNA substrate is processed into 24-nt siRNA preferentially by DCL3 due to its length specificity, facilitating the subsequent RNA-directed DNA methylation process (Blevins et al. 2015; Zhai et al. 2015). The transcription of short RNAs by Pol IV, and the length and 5-adenosine substrate preference of DCL3 might be essential mechanisms to prevent other DCLs from processing specific dsRNA substrate needed for the TGS pathway. Such coupling of RDR-Dicer-RNAi is also known in fission yeast, where a Dicer physically interacts with an RNA-dependent RNA polymerase to form coupled ma chinery that drives siRNA-mediated TGS (Colmenares et al. 2007). In addition, DCL3 can participate in 24-nt siRNA production from longer transcripts with aid from another RNase III enzyme, RNase III-like 2 (RTL2). As a class II RNase III enzyme, RTL2 possesses one RNase III domain and two dsRBDs, and is involved in rRNA maturation [in vivo is implied]in A. thaliana (Comella et al. 2008). Recombinant RTL2 protein can cleave long dsRNA substrates into 25 bp or longer dsRNA in vitro (Kiyota et al. 2011). Recently, it has been shown that RTL2 processes a subset of Pol IV-dependent dsRNA into shorter intermediates, which are preferable for DCL3 activity in vivo (Elvira-Matelot et al. 2016). Although no direct interaction has been reported, RTL2 and DCL3 can be considered other examples of coordinated action of a dsRBD-containing protein and a Dicer in plants. DCL3 is also reported to physically interact with the dsRNA-binding protein DRB3 in the antiviral RNA-directed DNA methylation pathway (Raja et al. 2014). The function of DRB3 in DCL3 activity rem ains elusive. Inorganic phosphate, NaCl and KCl differentially regulate DCL3 and DCL4 activities In the same assay system using crude extracts, inorganic phosphate at a physiological concentration promotes DCL3 activity but suppresses DCL4 activity toward 50-nt dsRNA substrates (Nagano et al. 2014). The differential effe
Wednesday, November 13, 2019
The impact of Queen Victorias Death on Australia :: essays research papers fc
Queen Victoriaââ¬â¢s Death Queen Victoriaââ¬â¢s reign, lasted 63 years, from 1837 to 1901. She ascended the throne of Great Britain, when she was 18. Despite being the Queen of Britain, and a very influential and prominent person, she also had an impact on Australian history. In Australia the most apparent legacy of Queen Victoriaââ¬â¢s reign is manifested in the names of the two states, Victoria and Queensland. There are also a large number of other important buildings and places, named in her honor such as, the Queen Victoria Building, in Sydney. Victoria was loved and respected by her subjects, and Australian society at the time was affected greatly by the loss of their beloved Queen. An example of the affection and grief felt by the Australian people is apparent in the following poem, written by J D Horne of Castlemaine, Victoria. ââ¬Å"Who can recall to memory the life Of one so loved, so dear ââ¬â A devoted mother, Queen and wife A friend when few drew near ââ¬â And not in silent agony Be melted into tears. A nation weeps her, The whole world mourns her... Dead, did I say? Ah! No! She lives In every loving heart. A nationââ¬â¢s grief is not assuaged ââ¬â No time can heal the smart. She lives forever, and her deeds Will live in memory too, And history recount her praise For all the ages through. For never monarch lived on earth So worthy of our song...â⬠à à à à à The Victorian era, as it became known, was the time of Queen Victoriaââ¬â¢s reign. Victoriaââ¬â¢s death signaled the end of an era. It was a rich and significant period in Britain, which had a positive influence on Australia also. It saw profound social changes culminating in the rise of the middle class, population growth, and an increase in wealth. Victoria was Queen and so it was seen as a product of her reign and so the love for her increased. Victoriaââ¬â¢s death created a feeling of insecurity and uncertainty of what would result. However, it also created the feeling of opportunity and a new beginning. ââ¬Å"There was a sense not only in London but in all the capitals of the world that an age had come to an end, a stronger sense than there had been when the 19th century itself drew to a close.â⬠(1). à à à à à There were mixed feelings with the end of Victoriaââ¬â¢s reign. At the time Australian culture still revolved around Britain and most Australianââ¬â¢s were either born in Britain, or had relatives residing there.
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