Wednesday, May 6, 2020
Amazonââ¬â¢s Culture How to Shape an Enduring Organizational...
Amazonââ¬â¢s Culture: How to Shape an Enduring Organizational Culture à « Leadership à « Stephen Blandino 11/07/2013 11:33 About Speaking Coaching Products Contact Personal Growth Leadership Church Organizations Culture Misc Amazonââ¬â¢s Culture: How to Shape an Enduring Organizational Culture March 23, 2012 ââ¬â 2 Comments The growth and success of Amazon.com is remarkable. Thereââ¬â¢s a good chance youââ¬â¢ve ordered something (or many somethings) on Amazon. You might even be a loyal customer taking advantage of Prime Membership with free 2-day shipping. But what you might not know is how Amazon created their organizational culture. 6 Tweet 3 Like Recently Iââ¬â¢ve been reading Change or Die by Alan Deutschman. Inâ⬠¦show more contentâ⬠¦And while itââ¬â¢s easy to make quick hires so that you can lighten your own load, doing so can be lethal to the organization. Bezos was brutal in his hiring discipline. But he had to be if he wanted to firmly establish the right culture. There are a number of things that define your culture, but the people you hire are the most influential in creating culture. They bring to the table their beliefs, values, and behaviors which shape culture from the very beginning. Bezos said, ââ¬Å"Cultures are these fantastic things. Cultures are not so much planned as they evolve from that early set of people. Once a corporate culture is formed, it tends to be extremely stable. It stays around. It ends up building on itselfâ⬠(p. 49). To create or protect a healthy organizational culture, youââ¬â¢ll need an effective hiring process. Furthermore, you need to know what types of questions to ask. I donââ¬â¢t believe you have to hire people exactly like you in terms of skills. In fact, doing so may keep the organization from gaining traction. But you must recruit people with the same DNA. Skills determine if a job gets done. But DNA determines if the organization stays true to its vision. Question: What have you found to be a practical way to shape the culture of your organization? You Might Also Like My Top 10 Posts of 2012 Dave Ramsey s Momentum Theorem 8 Words That Define Your Church s Culture Search... Post to TwitterShow MoreRelatedStrategic Management and Information Systems19841 Words à |à 80 PagesDemonstrate how Porterââ¬â¢s competitive forces model and the value chain model help businesses use information systems for competitive advantage. 4. Demonstrate how information systems help businesses use synergies, core competencies, and network-based strategies to achieve competitive advantage. 5. Assess the challenges posed by strategic information systems and management solutions. 3.4 CHAPTER OUTLINE 3.1 ORGANIZATIONS AND INFORMATION SYSTEMS What Is an Organization? Features of Organizations HOW INFORMATIONRead MoreAssignment on Business Strategy5549 Words à |à 23 Pagesgeneral public: ââ¬Å"Everything we do is inspired by our enduring mission: * To Refresh the Worldâ⬠¦ in body, mind, and spirit. * To Inspire Moments of Optimismâ⬠¦ through our brands and our actions. * To Create Value and Make a Differenceâ⬠¦ everywhere we engage.â⬠These values are consistent with the stakeholder version of the mission: refreshment and value are echoed in addition to inspiration. 2. What does a Business model intend to achieve, and how? Evaluate any company of your choices Business ModelRead MoreStephen P. Robbins Timothy A. Judge (2011) Organizational Behaviour 15th Edition New Jersey: Prentice Hall393164 Words à |à 1573 PagesOrganizational Behavior This page intentionally left blank Organizational Behavior EDITION 15 Stephen P. Robbins ââ¬âSan Diego State University Timothy A. Judge ââ¬âUniversity of Notre Dame i3iEi35Bj! Boston Columbus Indianapolis New York San Francisco Upper Saddle River Amsterdam Cape Town Dubai London Madrid Milan Munich Paris Montreal Toronto Delhi Mexico City Sao Paulo Sydney Hong Kong Seoul Singapore Taipei Tokyo Editorial Director: Sally Yagan Director of Editorial Services:Read MoreInnovators Dna84615 Words à |à 339 Pagesmore innovative and changing the world. One of the most important books to come out this year, and one that will remain pivotal reading for years to come.â⬠Chairman and CEO, salesforce.com; author, Behind the Cloud ââ¬Å" e Innovatorââ¬â¢s DNA is the ââ¬Ëhow toââ¬â¢ manual to innovation, and to the fresh thinking that is the root of innovation. It has dozens of simple tricks that any person and any team can use today to discover the new ideas that solve the important problems. Buy it now and read it tonightRead MoreExploring Corporate Strategy - Case164366 Words à |à 658 Pages22/10/2007 11:54 Page 599 Guide to using the case studies The main text of this book includes 87 short illustrations and 15 case examples which have been chosen to enlarge speciï ¬ c issues in the text and/or provide practical examples of how business and public sector organisations are managing strategic issues. The case studies which follow allow the reader to extend this linking of theory and practice further by analysing the strategic issues of speciï ¬ c organisations in much greater depthRead MoreContemporary Issues in Management Accounting211377 Words à |à 846 Pagesand colleagues contribute to this volume to recognize Michaelââ¬â¢s contributions to academic accounting. I am honoured to join them. Anthony G. Hopwood University of Oxford December 2005 PREFACE ââ¬Ë A multitude of forces shape management accounting. 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Tuesday, May 5, 2020
The Hazards Of Smoking Essay Research Paper free essay sample
The Hazards Of Smoking Essay, Research Paper The jeopardies of smoking Smoking coffin nails is really risky to the wellness of tobacco users and the wellness of the people around them. Many people die because of inhaling coffin nail fume every twelvemonth. Some of the harmful ingredients in coffin nail fume are nicotine, C monoxide, and pitch. Nicotine is habit-forming. It is besides one of the most unsafe chemicals in coffin nail baccy. Nicotine begins to consequence the a tobacco user s blood force per unit area, the flow of blood from their bosom, their bosom round, and take a breathing rate. Cigarette tobacco users are addicted to the nicotine in coffin nails merely like a drug addict is addicted to heroine or cocaine. When a individual smokes a coffin nail the organic structure reacts about instantly. Carbon monoxide is the same toxicant gas released from a auto s fumes pipe. Carbon monoxide is a colorless, odourless extremely toxic gas that reduces the sum of O the blood can transport. Carbon monoxide amendss the interior walls of the arterias that encourages the buildup of fat. Another Chemical in coffin nails is tar. Pitch contains at least 30 malignant neoplastic disease doing thorns. It is a mixture of several substances that condense into a gluey substance in the lungs. Tobacco makers have produced a coffin nail that is low in pitch and nicotine to cut down the opportunity of malignant neoplastic disease. Filters help to cut down the sum of chemicals inhaled by tobacco users but they do non halt them wholly. Cigarettes have some really harmful ingredients in them. One disease related to smoke is bosom disease. Some respiratory related diseases that have been linked with smoke are lung malignant neoplastic disease, malignant neoplastic disease of the voice box, chronic bronchitis, and emphysema. The jeopardies of these diseases increases with the me asure of coffin nails smoked and the length of clip the wont continues. Smokers are warned by a compulsory label on all coffin nail boxes every clip they smoke. Smokers are cognizant that smoking effects their wellness by agencies of lung malignant neoplastic disease, bosom disease, and emphysema. All of these are evitable. When a tobacco user inhales baccy fume into his/her lungs it passes through tubings called bronchial tube which causes harm to the cell liner. During the exposure to cigarette smoking the bronchial tube produces excess mucous secretion to clean away the stuff left behind the fume. Some of the sings are uninterrupted coughing, frequently coughing up mucous secretions assorted with blood, and chest strivings. If a tobacco user quits at this point, there is a good opportunity that the bronchial tube can return to normal. Heart disease is dramatically increased by smoking coffin nails. The good intelligence is that a tobacco user s hazard of developing lung and other malignant neoplastic diseases can be reduced by discontinuing. The hazard reduces instantly when a tobacco user starts smoking less or quits smoking wholly. Emphysema is a lung disease that destroys the snap of the lungs and impairs its ability to inhale and expire decently. In earlier symptoms of emphysema tobacco users finally find it hard to take a breath. For case, during or afte r physical activity a tobacco user will happen themselves short of breath, or even panting for air. Victims of emphysema frequently die of bosom onslaughts because of the old ages of increased emphasis on the bosom. In advanced instances, emphysema and chronic bronchitis may do thorax malformations, overpowering disablement, bosom expansion, terrible respiratory failure or decease. Equally of import, is how cigarette fume effects the wellness of others. Secondhand fume is merely every bit unsafe as smoke. In a closed room coffin nail fume can bring forth adequate C monoxide to impact everyone who is in it so smoking has become restricted within most companies and concerns. Smoke is normally restricted to designated countries that are usually outside the edifice. Pregnant adult females decidedly, should non smoke. When the female parent fumes, so does the unborn babe. A pregnant adult female who smokes passes the toxicants of the coffin nail baccy on to her babe. Pregnant female parents besides run a high hazard of holding kids with birth defects. Their babes frequently weigh less, which causes extra jobs for the babe s wellness. The sawbones general warns that smoking # 8220 ; may perplex gestation # 8221 ; and # 8220 ; smoking by pregnant adult females may ensue in foetal hurt, premature birth and low birth weight # 8221 ; Non-smokers involuntarily inhale fume from other people s coffin nails, which sometimes causes them oculus, nose or throat annoyance, in add-on to coughing and sneeze. Nonsmokers who live in the same house as a tobacco user have about twice the hazard of developing lung malignant neoplastic disease as non tobacco users who live in a fume free-environment. Here is what you can make to protect you and your household from the unsafe effects of fume and tobacco users: wear t fume in your house or allow anyone else smoke in your house ; don t fume or let anyone to smoke around your kids particularly babies and yearlings ; and in eating houses inquire to sit in the nonsmoking country. In shutting, it has been medically proven that coffin nails have many unsafe effects on a tobacco user s life. Cigarette smoke is the taking cause of premature decease in this state. Smoking non merely harms the wellness of the user, but besides the wellness of non-smokers who portion the same infinite. Not smoking and halting tobacco users from smoking are the two most of import things we can make for ourselves and our loves 1s in order to populate longer lives. Part II I chose to make my study on smoking coffin nails because I frequently see immature people smoking believing it is cool. Not merely does it destroy their image, but it besides ruins their wellness. Young people are ever seeking to smoke, and older, wiser people are ever seeking to discontinue. In making this study I have learned more about the unsafe chemicals I have ever known were in coffin nails. I have learned that cigarettes cause more than merely lung malignant neoplastic disease. Besides, I have learned that filters in coffin nails are non every bit good as I thought. Bibliography 1 ) # 8220 ; Smoking # 8221 ; Encarta. 1997ed. CD-ROM Redmond: Microsoft, 1993 333
Thursday, April 9, 2020
The Suffering of the Proud Essay Example For Students
The Suffering of the Proud Essay Pride is a key to self-respect; however, when it goes to far, people forget that humility is a virtue too. In the play Antigone, pride plays a major role throughout, appearing as fatal flaws in both Antigone and Kreon, the main characters of Sophocless tragedy. For Antigone and Kreon, as soon as the stepped past the line of humility, they were doomed to fail. For example, Kreon became so proud of himself he refused to listen to others warnings and assumes the gods are on his side. But didnt that girl do wrong? The whole nation denies it. Will the nation tell me what orders I can give? Kreon, Haimon, Kreon 881-3 this is a perfect example, because he refuses to listen to his son, and then, when presented with the fact that the whole nation thinks he is wrong, decides that he doesnt care what the nation thinks. Throughout the play, his advisor, Koryphaios, repeatedly gives him gentle warnings, and Kreon claims he is getting old, ignores him, or refutes him with points that only emphasize his out-of-control pride, such as, Men our age, learn from Kreon 876. He also assumes that the gods will go along with whatever he says, can you see the gods honoring criminals? Impossible Kreon 364-5. We will write a custom essay on The Suffering of the Proud specifically for you for only $16.38 $13.9/page Order now This kind of attitude is something that appears in almost every Greek myth, the thought that the gods will side with them no matter what, and it always ends up biting them in the rear. Furthermore, Kreon holds his subjects in contempt, and feels that their opinions are a complete waste of his time. Kreon thinks there is nothing wrong with killing them if they displease him. He accuses the sentry who brings news of the burial, of being the culprit, and of course the only reason is because he is the closest person, but Kreon doesnt care. He exclaims to his advisor, You are an old man, are you senile? Kreon 353. He insults and degrades his own advisor, someone he is supposed to trust implicitly. The final, ultimate sign that he thinks he is better than everyone comes when his son, Haimon, confronts him. He refuses to even listen to his suggestions, degrades him, calling him too young, too idealistic, and under the control of a woman. Kreon then tries to kill Haimons fiancÃÆ'Ã ©, right in front of him. Though the people in power control a nation directly, but the people in general indirectly control who rules them, if they want, and so a cruel or malevolent ruler, will always fall, and often violently. Finally, Antigone was so proud she could not try and change what was wrong, she just broke a law, and a law, weather right or wrong, should never be broken. Do you dare, despite Kreon? He cannot keep me from my own Ismene, Antigone 54-5. This is a perfect example of Antigones refusal to talk or reason with Kreon, and to just act, without thinking, and deciding that her morals are more important that the law of the land. She also refuses to back down, even once she is captured. Some people might argue that she is standing up for what she believes in, but if she had killed someone, because she felt that you may not murder is not a good law, would people agree? When people forget to be humble, they sew the seeds of their own destruction, they also often forget to listen to others, respect their junior, and sometimes even their seniors, and many time they break laws, forgetting that they are not gods, and cannot chose their fate.
Monday, March 9, 2020
Virtu And Fortuna Essays - Italian Politicians, Machiavellianism
Virtu And Fortuna Essays - Italian Politicians, Machiavellianism Virtu and Fortuna Virtu and Fortuna Under close scrutiny, The Prince by Niccolo Machiavelli is seen to be a mind-baffling construct of many levels of meaning, and, many might say, enigmatically so. It is hard to determine where Machiavelli is writing in earnest and where in sarcasm or self-condemnation. As John Plamenatz says, the perverse Machiavelli "likes to make himself out worse than he is. He likes at times to shock his contemporaries..." No doubt he succeeds. The important message here, though, is that the reader can never be positive of Machiavelli's real views. The same is true in considering the significance of the terms virtu and fortuna (and their several translations), so often used by Machiavelli to drive home his points. But by looking at many possibilities for their frequent and seemingly suggestive usages, and at some of the ancient thought with which Machiavelli was supremely familiar, we can arrive at a satisfactory speculation, we can discuss the web weaved by Machiavelli in his profes! sions. The first, most obvious purpose of The Prince is stated by the author himself, addressing Lorenzo de' Medici: If you will read [this book] over and study it carefully, you will recognize in it my most earnest desire that you may achieve that summit of grandeur to which your happy destiny and your other capacities predestine you. And if from that summit Your Magnificence will occasionally glance down at these humble places, you will recognize how unjustly I suffer the bitter and sustained malignity of fortune. Clearly there is a sizeable amount of cajolery occurring here (and also foreshadows the following discussion of fortune and virtue), and this same stroking of Lorenzo's ego continues through the book, with slight references to how fit to rule this prince is, how "virtuous," how fated to be the incredible Prince for whom Machiavelli writes. It could easily be said that with this book the author may have trying to ingratiate himself to all the local nobility; on the other hand, knowing what follows might also suggest that Machiavelli was really attempting to play off the nobility's fears of chaos and insecurity, guaranteeing safety if they read his short piece. The second possible purposedefinitely an outcomeis the creation of a learned historical discourse. I will leave out examples; it suffices to say that The Prince encompasses many centuries of human history, many deeply researched examples of politico-military events, and so on. True, they serve enforce his ideas on "virtuous government," but they also seve the modern historian in his search for original sources. A third possible purpose of The Prince might be to outline the ideal government or, if not the ideal, the most virtuous or the best possible. It is in this purpose, the same goal pursued by countless political thinkers in history, that we extract much of what the current age considers Machiavellian. The lord most would consider ruthless and cold, but whom Machiavelli names a virtuoso, is but one (probably Cesare Borgia, son of Sixtus IV) character in the book. The author's supposedly cruel way of equating bad with good is traditionally what has gotten him into hot water. The fact is, however, that Machiavelli never truly addresses the issues of bad and good, right and wrong, these absolute judgments most people would, I think, claim him to make. Machiavelli, in laying out the "best" government, does so from a completely political and pragmatic point of view, by what works, what is possible, and, really, what for his prince results in the most power and security. The auth! or carries out this investigation using two parameters in particular, the Italian virtu and fortuna. They can be translated in many ways (Robert M. Adams has done it very nicley so I shall not repeat them here) which is part of what gives the book its depth. In general, though, the spirit Machiavelli attaches to these two crucial words resembles the following. Virtu embodies a paragon or paradigm; the virtuous man takes action, he anticipates and exhibits resolve, shrewdness and aptitude. Above all, he commits himself to politically sound, whole-hearted efforts. Politics here reign supreme; while he does acknowledge that there are ideals in the world, he asserts that it is futile to discuss them because
Saturday, February 22, 2020
The Changing Representations of African Americans in Drama Essay
The Changing Representations of African Americans in Drama - Essay Example The fact that "racism inscribed in the nation's Constitution and legal history has practically insured that a national tendency towards blindness, psychosis and stammering around race would carry over into the 21st century,"(Tate 44) and this is clearly demonstrated in America's modern media. Today we see the demonstration and celebration of the clever and reflective achievements of African Americans not only in the field of entertainment, but also in other distinct fields as well. This paper will explore the changing representations of African Americans in theatre and television. I will also examine the implications of these roles and the ways in which they influence othersââ¬â¢ perceptions of the black race. There are many intelligent Blacks working in the American theatre today who have labored to bring forth its daring and often healing truths. Reviewing the bulk African American performance, theatre and drama, and brings into focus the years of glory of the Harlem Renaissance, ranging from the plays and sporting events to fights and dances. To assess the development in the American African theatre, one needs to examine the important contributions of the black male and female playwrights. With the contemporary focus on multi-cultural theatre, anthologies of plays by African Americans are important additions about the Black theatre because the number of venues in producing plays by African American authors has greatly increased (Collier). Criteria that make a television and film drama great and some productions mediocre are the significant stories that show the age and the period by portraying the characteristic conflict and choices and immediate circumstances of the charactersââ¬â¢ lives. ' lives. Today, the visual media and studies are employing different approaches and methods whereby some skim the surface and shun the question of value, while others penetrate beneath the surface and take on questions of value in the most direct way. Drama and movies have presented models that have had the ability of being challenging, probing, insightful and therapeutic by portraying believable characters in credible situations, challenged to make choices. It is clear "America is experiencing a new black cultural renaissance, and nowhere is it more evident than on the nation's theatre stages." (Nesmith). While old stereotypes are not completely gone. Some shows project Blacks as lazy and not wanting to better themselves, when in reality it is an enormous struggle to overcome oppression and gain equal opportunities for themselves. Everything produced on the television cannot always be great drama. Certain shows set back race relations because their view of Black assimilation is not projected positively. But the works of the African American playwrights present the philosophy and magnitude due to the depth of the inner unity between the characters and the concrete collisions of the socio-historical forces of their time. Around the 1950's, the visual entertainment was shifting toward television shows, and it became important for the survival of the motion picture to have new ideas. This resulted in the 1950 Hollywood presentation of a Black middle class family, "No Way Out." "Thirty years ago, at the height of the Civil Rights Movement, in the year Malcolm X was shot and riots broke out across the country, Douglas Turner Ward used comedy and satire to deliver a message of the
Wednesday, February 5, 2020
Software localisation Essay Example | Topics and Well Written Essays - 2000 words
Software localisation - Essay Example (Reg1a) Alchemy Catalyst combines the power and flexibility of regular expressions like ezParse which makes it simple and quick to work with visual development environment in order to develop text parsers for virtually any file type. EzParse also supports the most popular encoding systems such as UTF-8, UTF-16 and Shift-JIS. (Cat1a) Requires personnel management, work organisation, planning, analysis, setup and coordination of resources, deployment of tools and software, tracking, reporting, and most of all flexibility. During the first analysis of the files that are to be localized we try to determine whether a glossary containing new terminology is necessary. At the same time we examine the extent of the project, and, depending on the deadline, we choose the most suitable means and technology for the work. Based on this analysis a list of files is generated, and a glossary; styles and formatting are defined, and procedural rules are established. We maintain full consultation with the customer. (Stage1a) Localization includes several levels of quality checking. ... Q3) a) Project Management Flow: Project Commencement Which activities would be undertaken, which areas would be addressed during this stage of the project, and what would be the output Requires personnel management, work organisation, planning, analysis, setup and coordination of resources, deployment of tools and software, tracking, reporting, and most of all flexibility. During the first analysis of the files that are to be localized we try to determine whether a glossary containing new terminology is necessary. At the same time we examine the extent of the project, and, depending on the deadline, we choose the most suitable means and technology for the work. Based on this analysis a list of files is generated, and a glossary; styles and formatting are defined, and procedural rules are established. We maintain full consultation with the customer. (Stage1a) b) Production Flow: Evaluation Which areas of a product would be covered during evaluation stage and what would be the output at this stage. Evaluation is done when the software is implemented at the client side in order to estimate the degree of accuracy needed from the software according to the business requirements. Production actually covers the translation itself, and document composition. This phase affects the quality of the product the most. Continuous Control: During the production period our customers are encouraged to check the translated text. They can see and verify that everything is being done as they require. Quality Checking: Localization includes several levels of quality checking. Language experts read through the whole text prior to the application of standard controls for translation precision, style, terminology and content. Special
Tuesday, January 28, 2020
Characterising the Atmosphere of Proxima B
Characterising the Atmosphere of Proxima B 1.Intro As of April 2016, 582 extrasolar planets have been discovered (NASA) using Doppler spectroscopy, a method for detecting extrasolar planets by deducing their radial velocity from the Doppler shifts in the spectrum of the planets parent star. Using this method, Anglada-Escude et al (2016) recent observations have revealed a 1.3 Earth mass planet orbiting the red dwarf Proxima Centauri. Although Earth-like planets arent uncommon, the recent discovery of Proxima b is particularly exciting as at a distance of 1.3 parsecs it is our closest potentially habitable star. Where previous studies were stunted by the distance of the host star to the Earth, Proxima b may within reach of Earth and space based telescopes giving us the ability to better judge its characteristics. While Proxima b is in the goldilocks zone, meaning it has potential to have water and perhaps even life, it is subject to intense radiation and solar wind. The habitability of Proxima Centauri b and Prospects for characterising the atmosphere of Proxima Centauri b question whether Proxima has an atmosphere, with the primary focus being whether Proxima b can maintain liquid water on its surface. The former does this by estimating the current high-energy irradiance of the planet and show that the orbit is likely to be in either a synchronous or 3:2 spin-orbit resonance. The latter article considers measuring the variation in thermal emission with orbital phase as a method for characterizing Proxima bs atmosphere. 2. The habitability of Proxima Centauri b 2.1 SummaryIn this paper the authors work through a number of factors that could affect the potential habitability of Proxima b. While noting there is a surplus of Earth like planets (Kepler), the authors need question whether Proxima lies within the Habitable Zone, where a stellar flux is low enough to maintain surface water but high enough to maintain the planetary surface as defined by Kasting et al. Due to a stellar input of ~65% than of the Earth Proxima b lies within these limits. High Energy IrradiationHigh-energy emissions including X-rays through to far-UV (FUV) and particle winds are known to influence atmospheres of rocky planets. A particular issue when estimating the XUV fluxes is that Proxima is a flare star (haish et 1983) meaning its HE emissions can vary significantly. The work in the paper was built from X-ray emission observations via ROSAT and XMM that report log LX = 27:2 erg sà ´Ã¢â ¬Ã¢â ¬Ã¢â ¬1 g and LX = 27:4 erg sà ´Ã¢â ¬Ã¢â ¬Ã¢â ¬1 respectively (Haish 1999). To generalise the overall dose on the planetary atmosphere, the authors consider the average XUV luminosity over an extended timescale while accounting for flare variation. Using XMM-Newton observations, the strongest flare has an energy of about 210^31 erg. CN Leo has a similar X-Ray luminosity and thus can be used to model flare distribution for Proxima. Audard el state a power law with the form N(> E) = 3:7 _ 1037Eà ´Ã¢â ¬Ã¢â ¬Ã¢â ¬1:2, where N is the number of flares per day, and E is the total (integrated) flare energy in erg . This shows CN Leo has flares with energies greater than about 2 _ 1031 erg over a timescale of 1 day.This is found to be in agreement with the XMM-data set, consolidating this is a reliable representative of the daily flux. Thus giving (between 0.65 and 3.8nm) a time integrated average flux of 87 ergss_1cm^-2 . To account for more energetic flares a calculated extra 22 ergs s^-1 cm^-2 is added, totalling at 109 erg s^-1cm^-2 . Flux estimates (including flare contribution) were calculated over a range of wavelengths, as listed below: ROSAT observations for the 3.8nm to 10nm range produced an X-Ray dose of 163 erg s^1 cm^2 EUVE spectrum for the extreme UV 10nm to 40nm range produced a flux value of 111 ergs^1cm2 FUSE observations for the far UV 92-118nm range produced a flux value of 20 egs HST/STIS for the 118-170nm range produced a flux value of 130 ergs Therefore between 0.6 and 118nm, the total integrated flux today that is a fair representative of HE radiation on the atmosphere of Proxima b is of 307ergs^1. For comparison purposes, the XUV flux at Earth is calculated to be 5.1 ergs, showing Proxima b to receive 60 times more XUV flux. This data is illustrated in fig. -Probability of capture: The authors remark on the poor parameterizations of previous work on tidal dissipation of rocky planets (Darwin 1880, love 1909, goldreich 1963), their primary issue being models would always predict an equilibrium rotation rate where tidal torque would vanish. The authors use the Andrade model as tailored by Efromsky 2012 and Eq 10 of Marakov 2012. The Andrade time was set to be equal to the Maxwell time of tm=500yr for simplicity. The results for 3:2 resonance capture probability are shown in fig. Curve a) indicates where tidal torque at the lower boundary of the separatrix is negative and greater than the maximum restoring torque. b) indicates tidal torque at the lower boundary of the separatrix is positive and (c) indicates where maximal tidal torque inside the resonance is greater than the maximum triaxial torque. Regions above (c) and/or (b) (white regions) leads to certain capture due to tidal torque, whereas below (c) and (a) (black region) capture is impossible as triaxial torque is too weak. The implication for climate would be that liquid water is possible depending on the rotation. If the planets orbital eccentricity is 0.06 it is likely Proxima will have a tropical belt. -water loss It is undeniable how estimates of volatile loss are poorly constrained, due to the lack of key data e.g. evolution of atmospheric composition, stellar wind properties, photochemistry of the upper atmosphere etc. The authors take a moment to discuss an alternative approach for determining Proxima bs volatile loss: Comparing Earths early development with Proxima bs. By considering how Earth built by a multitude of moon size protoplanets across 10Myr, the authors argue the XUV irradiation and stellar wind experience on proto-Earth is comparable to that of Proxima b. lamer et al modelled volatile losses of early Earth showing significant loss caused by hydrodynamic escape of hydrogen and strong stellar wind exposure. Due to the fact the runaway phase of Proxima is only longer than the Earths by a small factor 12 um. Finally, to determine how tightly the albedo and heat redistribution can be constrained, an MCMC fit was trailed on the simulated LRS spectrum from Fig 2 using the emcee package (Foreman-Mackey et al) The fit was run with redistribution, F, and albedo, A, as free parameters, from the fit one can measure F=0.07 and albedo A=0.13 to be well constrained. The authors conclude that a MIRI phase curve is sufficient means to determine the existence of an atmosphere on Proxima b. A then turn their attention to the feasibility of detecting an ozone absorption feature from Proxima b at 10um. Key motivation being this is a prominent feature of Earths IR emission spectrum and acts a potential evidence of present life. Bond albedo was set to A=0.3 to match Earths and an isothermal temperature arrangement is assumed. Using a modelling calculated by Rugheimer, that assumes an Earth-like atmospheric composition irradiated by a GJ 1214b-like star, it is noted that the ozone feature does not vary with planet orbital phase but is detectable from a very high signal-to-noise spectrum. The predicted feature amplitude was less than 1ppm. To illustrate how much observation time would be required to detect said feature, fig shows a simulated spectrum co-added from 60 days. The absorption feature at 9.8um corresponds to an ozone band and the dip at 8 is due to methane. 3.2 Implication/ImportanceA major concern would be that detecting modulations with JWST would be extremely challenging due to Proxima Centauri s stellar variability and flares. To estimate how feasible it would be to detect Proxima bs thermal emission, the JWST Exposure Time Calculator (ETC) was used to estimate signal-to-noise ratios for MIRI observations of Proxima Cen. Using a model spectrum, the ETC produced the expected count rate, which also correlated with the S/N predictions from Cowan et al. Although it feeds back good results, the paper highlights the need to test the precision of the MIRI detector. A general issue with this paper is calculations are simply based on possible observations with the James Webb Space Telescope, as opposed to actual recorded data. Realistically, conclusions drawn about phase variation for Proxima arent definitive, though the paper shows potential of the MIRI could do and show. Other recent paper including à ¢Ã¢â ¬Ã ¦.., have a general agreement that the JWST could be used to infer exoplanets rotation periods and dissipation rates. In theory, measurement using the MIRI (which covers the wavelength range of 5 to 28 microns) at different wavelengths could be used to find atmospheric signatures, constrain the radius, the albedo and the inclination of Proxima b, as well as its rotation. This paper consolidates this idea. 3.3 Assessment In the introduction many issues that could affect Proxima bs atmosphere are mentioned, for example Proxima bs evolutionary history, but these topics werent covered in the body of the article. The introduction also states three methods available to characterize the planets atmosphere. The last (measure variation in thermal emission with orbital phase) is the focus of this paper, however the first two (directly image the planet, measure variations in reflected starlight with orbital phase) were perhaps unreasonably undiscussed. The quality of the results is difficult to assess, on the one hand an abundance of assumptions were used, to the extent that all of Section Five of this paper lists assumptions about the planetary system used in the their analysis. In many cases decisions were poorly explained. For example an albedo of 0.1 is used in the climate model while commenting Proxima bs atmosphere would likely have a higher albedo (perhaps 0. Like Earths), however dont they elaborate on why they settled with 0.1. On the other hand many of the assumptions were heavily based on previous work by a variety of researchers. The need for atmosphere case with moderate distribution F=0.35 was driven by a plethora of research ((e.g., Joshi et al. 1997; Merlis Schneider 2010; Heng et al. 2011a, 2011b; Pierrehumbert 2011; Selsis et al. 2011; Leconte et al. 2013; Yang et al. 2013, 2014; Koll Abbot 2015, 2016; Turbet et al. 2016).) which have shown how the presence of an atmosphere can reduce the amplitude of IR phase v ariation by a factor two or more. This made decisions feel more reliable and justified. Yet, without having read referenced work, certain aspects were hard to follow. Some of their most significant work on simulated spectrum is noted to be built upon the work of selsis et al, however there is no indication of what work Sel actually conducted. The paper in general couldve done with a more substantial amount of explanation for this made for a frustrating read. 4. Comparison In terms of writing style, It is apparent anglada had done a more extensive amount of research, Work is important as it highlight the value of using a combination of space and ground telescopes and In terms of research, both papers take a focus on the effects of different eccentricities on a tidally locked planet and its atmosphere. K considered this when creating a climate model and simulated a measurement of the thermal phase variation whereas anglada deduced it is likely Proxima is in a 3:2 rotation and considered the implication of the HE radiation Proxima b would receive. Generally, the authors draw the same conclusion, that Proxima b could have an atmosphere, perhaps capable of supporting life. In the case of no heat redistribution or having synchronous rotation, Proxima b having an atmosphere is improbable. In the case or heat redistribution or asynchronous rotation, one could infer that an atmosphere or ocean is present. Theres a consensus that defining planet habitability is not straightforward, there are vast limitations on calculations that can be done and any modelling is not strongly representative of Proxima bs characteristics. Both papers also make use of modelling Earths past and current state as a forecast for Proxima bs development. Using the Earths past to give us more information to further determine Proxima bs atmosphere and potential habitability was fairly clever and intuitive concept. Future work, perhaps after the launch of the JWST, could consider this concept in more detail for a more well-rounded understanding of Proxima bs characteristics.In conclusion, both papers were particularly insightful, encourage future missions similar to Kepler, and will hopefully drive new research.
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