Friday, July 31, 2020

Living la vida lab rat

Living la vida lab rat A few entries back, Lena asked How did you get the job in the lab and are the experiments you do designed by yourself or postdocs, professors, and grad students? The easiest question there to answer is how I got my job. The summer before my sophomore year, I emailed about ten professors whose work looked interesting, including my resume and a short cover letter. I got responses from two faculty members, interviewed with one, and took the job. Ive been in that lab for two and a half years now; I work about 12-15 hours a week during term and 40 a week during summer and IAP. I have my name on a poster that was presented at the Society for Neuroscience meeting and on a paper thats being revised for publication in Cell. When I declared biology as my second major, I picked my UROP supervisor to be my biology advisor (if you have two majors, you get two advisors too), and he (apparently) wrote an absolutely stunning letter of recommendation for my graduate school applications. In the first project I worked on in the lab, the experiments were designed almost exclusively by the postdoc with whom I work directly, Albert. I was still learning how to do all the different lab protocols, and since I didnt know how to do most of them, I couldnt very well design my own experiments. Although I wasnt in charge of experimental design for this project, its not like Albert was hanging over my shoulder watching me do the experiments he usually doesnt bother me unless I ask for help. Alberts an MD/PhD, and works one day a week at Massachusetts General Hospital curing the sick, so even when I wasnt designing the experiments I had a lot of freedom and when Alberts not in the lab, I get to take over his desk! The project Ive been working on for the past year is my baby, and Ive done all of the technical work on it. Albert still helps me with experimental design, but I have a strong enough understanding of both the project and the technical options available to me that I have most of the control. Alberts always there to help me if I get confused or hit a dead end. I read all the literature regarding my proteins, and when we meet with Morgan (the professor in charge of our lab), its my job to prepare a short powerpoint presentation and explain our results to him. Albert says that if I finish the project by the time I graduate, I get to write the first draft of and be first author on the paper describing it. In some sort of larger sense, what I work on is constrained by what Morgan finds interesting if I woke up one day and wanted to start a totally new project unrelated to anything Morgans interested in, that probably wouldnt fly. Generally, youll get more freedom as you work longer in the lab and prove your competence to a greater degree, so good luck just walking into the office of a professor youve never worked for and proposing some crazy research project unrelated to their research goals. You dont generally get to do that as an undergrad hell, you dont generally get to do that as a grad student. You might get to do it as a postdoc. This is because science is run by the golden rule: he who has the gold makes the rules. In a proximal sense, the person with the gold is the professor (also called principal investigator or PI; in my case, Morgan) who runs the lab and gets NIH grants; in an ultimate sense, the government is the one with all the gold making all the rules. Science is overwhelmingly funded by grants from government agencies like the NIH, NSF, DOD, or DOE, and the research a given lab does is largely constrained by the optimization of what that lab finds interesting and what their favorite government agency is likely to fund. Until we get more rich friends like Howard Hughes (who started a foundation that lavishly funds the most promising 300 scientists in the US, twelve of whom are at MIT, including Morgan), thats the way things are going to be. This focus on doing research thats likely to be funded leads to what I like to call last sentence syndrome. The last sentence of every labs research description goes something like and this research will lend insight into the process by which [choose one: cells become cancerous, brains get Alzheimers, hearts get heart disease]. This is because the NIH is devoted to funding biomedical research, and likes to see that its buckets of money are being used to find cures. So when they see that last sentence, the NIH is all yayyyy! and the scientist getting the funding is all yayyyy! and the public reads about it in the newspaper and is all yayyyyy! and the people with life-threatening illnesses are all so that cure for my life-threatening illness that you said was going to happen with gene-transfer therapy ten years ago and with stem cells last year did you send that by FedEx? Because I HAVENT GOTTEN IT and maybe FedEx has the wrong address. kthxbye. So the moral of the story is that freedom is relative in science. And that we all need more rich friends. My week, and my weekend. I worked in the lab 30 hours this week. This was, of course, in addition to taking three classes, cheerleading, and answering an absurd number of questions on CC. And fun stuff, like walking home from work with Jessie, eating pizza in Bens office with the other bloggers, interviewing five GRT candidates for my living group, and stopping by Bens office and talking for an hour, resulting in me being late to cook dinner for Adam and Ben writing me an excuse note. So it was a good week, just extraordinarily exhausting. And Adam and I decided we needed to get off-campus and go out to dinner and see a movie. I wanted to see V for Vendetta because Id heard it was a gripping dystopic view of a totalitarian society; Adam wanted to see it because he heard that lots of stuff got blown up. Well, at least we both wanted to see it. We hopped on the T and got off at Kenmore Square, where we ate dinner at the Pizzeria Uno next to Fenway Park. (One of the best things about going to school next to a major city is that its really easy to get off-campus and eat at restaurants and do fun stuff. One of the best things about going to school next to Boston is that there are so many college students in town that you can do those things on a budget.) After that, we went to the movie (which was amazing) at the Fenway AMC, where I had to eat my apple pie from the restaurant with a straw because there were no plastic forks. It actually worked pretty well I slurped up the ice cream, then scooped the pie crust and speared the apples. Necessity is the mother of invention. Again. After the show ended, we hopped back on the T and got back to campus around 11. It was a nice little night on the town. Short answers to questions. 1. Anonymous asked Does anyone know how the proportion of women to men breaks down by department? Ask and ye shall receive. 2. A course 7 prospective wrote I was wondering if you could direct me to an entry that talks about the grad school application process. Im currently a freshie at MIT and was just curious about the grad school application process. My GPA is not looking too hot right now and I was wondering what a typical or range of GPAs would be for admission into a grad school (like the ones that you were admitted into; and congrats very much on ur successes! :)) and how much it matters that you attend a HYPMS/MIT vs. say a state school. (like will they even factor that inthat you went to a school w/ very little grade inflation?) First, heres my entry on grad school admissions. Second, yes, grad schools will most definitely consider the fact that you went to MIT. I had a 4.4(/5.0) when I applied, and I got into more (and better) programs than friends of mine from other schools who had 3.9(/4.0) or 4.0(/4.0) averages. At UC Berkeley, Stanford, and Harvards recruitment weekends, a little over 10% of the prospective students were from MIT. Think about how unlikely that is just from a sheer numbers perspective many, many students from state schools with 4.0s were passed over in favor of the MIT kids with imperfect grades. We have stellar research experience, and thats what graduate schools care about. If you shoot for an overall GPA of between 4.2 and 4.5 at MIT, you should be fine as long as you have plenty of research under your belt. Finally, I will note that your GPA will almost certainly go up from what it is freshman year. First term freshman year, I got a 3.25(/5.0) or would have, if first term werent pass/no record! and second term I got a 4.0/5.0, with a C in 8.02. Ive pulled two straight 4.8s in the last two terms, and now have a solid 4.5.

Friday, May 22, 2020

Elemental Composition of the Human Body by Mass

This is a table of the elemental composition of the human body by mass for a 70 kg (154 lb) person. The values for any particular person may be different, especially for the trace elements. Also, the element composition does not scale linearly. For example, a person who is half the mass may not contain half the amount of a given element. The molar amount of the most abundant elements is given in the table. You may also wish to view the element composition of the human body in terms of mass percent. Reference: Emsley, John, The Elements, 3rd ed., Clarendon Press, Oxford, 1998 Table of Elements in the Human Body by Mass oxygen 43 kg (61%, 2700 mol) carbon 16 kg (23%, 1300 mol) hydrogen 7 kg (10%, 6900 mol) nitrogen 1.8 kg (2.5%, 129 mol) calcium 1.0 kg (1.4%, 25 mol) phosphorus 780 g (1.1%, 25 mol) potassium 140 g (0.20%, 3.6 mol) sulfur 140 g (0.20%, 4.4 mol) sodium 100 g (0.14%, 4.3 mol) chlorine 95 g (0.14%, 2.7 mol) magnesium 19 g (0.03%, 0.78 mol) iron 4.2 g fluorine 2.6 g zinc 2.3 g silicon 1.0 g rubidium 0.68 g strontium 0.32 g bromine 0.26 g lead 0.12 g copper 72 mg aluminum 60 mg cadmium 50 mg cerium 40 mg barium 22 mg iodine 20 mg tin 20 mg titanium 20 mg boron 18 mg nickel 15 mg selenium 15 mg chromium 14 mg manganese 12 mg arsenic 7 mg lithium 7 mg cesium 6 mg mercury 6 mg germanium 5 mg molybdenum 5 mg cobalt 3 mg antimony 2 mg silver 2 mg niobium 1.5 mg zirconium 1 mg lanthanum 0.8 mg gallium 0.7 mg tellurium 0.7 mg yttrium 0.6 mg bismuth 0.5 mg thallium 0.5 mg indium 0.4 mg gold 0.2 mg scandium 0.2 mg tantalum 0.2 mg vanadium 0.11 mg thorium 0.1 mg uranium 0.1 mg samarium 50 g beryllium 36 g tungsten 20 g

Sunday, May 10, 2020

The Treasury Department s Actions - 806 Words

The Treasury Department’s Actions During the largest recession the United States has seen since the great depression, the Treasury Department sprung into action to stave off another depression. Within a short period of time after the housing bubble burst, financial institutions started to fail. Credit and liquidity virtually vanished within days. The government was forced to react quickly to thwart a complete financial collapse. An estimate from the public interest group Better Markets has calculated the cost of the recession close to $12.8 trillion (Puzzanghera, 2012). This number is criticized since it includes losses in economic output, GDP, and bail-outs, while home equity losses and consumer net wealth are not. This figure does give a good idea of the magnitude of the Treasury Department’s actions. A multitude of industries, and companies received direct financial aid. The government identified key economic areas where policies were needed, and provided credit and liquidity for growth in those are as. The quick response of the Treasury Department helped in reducing the negative effects of the financial crisis. The three economic theories that I identified in this financial crisis consist of classical economics, Keynesian economics, and aggregate market (AS-AD) analysis. There was also a fear of monetarism which has not come to fruition at this time. Economic Theories Classical economics is considered one of the original economic theories. It is based on theShow MoreRelatedThe Division Of Foreign Assets Control773 Words   |  4 Pagesâ€Å"The Division of Foreign Assets Control was established in the Office of International Finance by a Treasury Department order in 1950, after People s Republic of China entered the Korean War. 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Wednesday, May 6, 2020

High School vs. University Free Essays

Every September, high school graduates must prepare for the drastic transformation from high school to university. High school is a teaching environment which a student acquires facts and skills. University is a learning environment in which a student must take responsibility for thinking and applying what you have learned. We will write a custom essay sample on High School vs. University or any similar topic only for you Order Now This step in life students will either adjust to or struggle with. High school students are told university life is exciting, unpredictable, and entertaining. Also, students are informed university life is costly, demanding, and stressful. In order to adapt to the transition, students must understand and recognize the different teaching styles, testing, and grading. Teaching styles change as class sizes vary. Teachers in High school cover course material in depth and over a long period of time. Professors cover textbook material quickly. High school teachers check homework, remind students of incomplete work, and approach students if assistance is needed. Professors do not check completed homework and will assume students can complete the same tasks on tests. It is left up to the student to communicate with their professors in order to receive extensions ensuring the student will not be penalized. Professors do not approach students or notice students who are struggling. Therefore, students may approach professor in given office hours for one-on-one help. Finally, in university due to large class sizes and minimal lecture time keeping up with assignments and readings is critical. Cramming the night before a test and receiving a good grade is more likely to occur in high school, where testing in subjects is very frequent. Preparation for testing becomes more crucial in university because tests are infrequent, covering large amounts of material. Also, students in high school may be awarded a make up test normally without an explanation. Whereas in university, in order to receive a make up test a reasonable explanation must be given. Review classes are given in high school to help prepare students and give them a clear idea of the material that will be tested. Rarely, are review sessions provided for university students, if they are, professors expect participation from students who attend. Success on tests can be mastered by applying acquired knowledge to new situations or to solve new problems. The grading system becomes very important as students enter university. High school students are used to courses that are usually structured to a â€Å"good-faith effort†. In high school grades are given for most assignments. Students are also given grades for consistently good homework, which may help boost marks when test grades are low. Students who may not have a good overall mark occasionally have the opportunity to complete extra credit projects. Comparing this to university grades on tests and major papers usually provide most of the course grade. Extra credit projects are not normally allowed to raise a grade in a university course. Therefore, the â€Å"good-faith effort† is important in regard to the professor’s willingness to help students achieve good results; it will not substitute for results in the grading process. Adjustment is required for a high school graduate to be successful in university. Before entering university, high school students must be aware of these differences. Therefore, they must know how to adapt to new teaching styles, to successfully prepare themselves for testing, and the changes in grading systems. Recognizing these differences before entering a university can help prepare students for greater success. How to cite High School vs. University, Essay examples

Wednesday, April 29, 2020

There are many types of software development model Essays

There are many types of software development models with many different uses, pros and cons. This essay will list four different software models and their uses. The first software model is Six Stigma. Six Stigma is known as the perfectionist of the software model world and is used by major companies due to it's high success rate. Six Stigma tends to be very strict on their defect policy and only allows companies to produce 3.4 defects out of every million products. A defect is anything outside of a customer's specification. This has caused Six Stigma to have an extremely thorough policy. Six Stigma has two different routines for two different types of businesses and their necessities. For businesses that already exist and are falling below S.S. standards, there is the D.M.A.I.C. (Define, Measure, Analyze, Improve, Control) system. And for projects and/or products that haven't launched yet, there is D.M.A.D.V (Define, Measure, Analyze, Design, Verify). Though, many people tend to roll their eyes at Six Stigma and say that it is a waste of time and not necessary but most of the time those are people that don't know how to correctly use it. Though, this hasn't stopped Six Stigma from having Black Belt employees that save approximately $230,000 per project and can complete 4 to 6 projects in a year. In fact, General Electric, a large company that uses Six Stigma has estimated benefits on the order of $10 billion during the first five years of implementations. The second software model to discuss is Waterfall. Waterfall is a sequential design process. Process is seen as flowing steadily downwards and through conception, initiation, analysis, design, construction, testing, production, and maintenance. About 20-40% of time is dedicated to the first two phases and 30-40% is dedicated to coding. The rest is dedicated to testing and production. Waterfall was originally specifically for manufacturing and construction but the cases progressively got more costly and harder to fix, causing them to swap to a more office software' field. Waterfall is a bit more aged than the rest. When Waterfall first launched, there was no real formal software developments that existed yet. Waterfall actually converted into software modeling. The Third software model would be Scrum. Scrum is often perceived as methodology but is more of a framework for the management process. Scrum is all about teamwork and believe that there should be no dictating leader of a group. For instance, when a new project is made or launched, many decisions are left up to the scrum software team because they are trained to solve problems. Scrum heavily relies on a strong, independent, self-organizing, cross-functional team of software designers. Cross-functional as in the fact that without the help of every team-mate, they wouldn't be able to turn a feature into an implementation. Agile is our last software model and it is mostly known to be paired with Scrum. Agile is a set of Values and principles for software development which are constantly evolving as technology changes. Agile is very big on accepting change and adapting to new advances in the technological world, plus, a rapid response to it. Agile truly and heavily believes in face-to-face communication with customers and workers as well.

Friday, March 20, 2020

The Scarlet Letter Plot Summary

'The Scarlet Letter' Plot Summary The Scarlet Letter is an 1850 novel by Nathaniel Hawthorne set in Boston, then the Massachusetts Bay Colony, in the mid-17th century (about fifty years before the nearby Salem Witch Trials). It tells the story of the relationship between the Puritan community and Hester Prynne, the protagonist, after it is discovered that she bore a child out of wedlock- an act that cuts against society’s religious values. As punishment for her actions, Prynne is forced to wear a scarlet â€Å"A,† which, as it is never said outright, presumably stands for â€Å"adultery† or â€Å"adulterer.† The narrative, which is framed by an introductory piece entitled â€Å"The Custom-House,† depicts the seven years following Prynne’s crime. The Custom-House This introduction, written by a nameless first-person narrator who shares many biographical details with the book’s author, serves as the main narrative’s framework. In this section, the narrator, who has an interest in writing, tells of how he works as a surveyor at the Salem Custom House- a moment he takes as an opportunity mainly to disparage and mock his colleagues, many of whom are older and have secured lifetime appointments through family connections. This section takes place in the mid-19th century, and, as such, the Custom House has much less activity than it did during its heyday two centuries earlier. As a result, the narrator spends a good deal of his time snooping about in the attic of the building, whereupon he finds an old piece of red cloth in the shape of the letter â€Å"A,† as well as a century-old manuscript by a previous surveyor named Jonathan Pue, about a series of local events from a century even before his time. The narrator reads this manuscript, and then reflects on how his Puritan ancestors, whom he holds in high esteem, would have looked down on him writing a work of fiction, but, after he loses his job as a result of a shift in local politics, he does so anyway. His text, loosely based on the Pue manuscript, becomes the basis of the novel. The Scarlet Letter In mid-17th century Puritan Boston, then the Massachusetts Bay Colony, a local woman, Hester Prynne, is discovered to have had a child out of wedlock. This is a major offense in the extremely religious community. As punishment she is made to stand for several hours with her child, Pearl, in  a stocks on a scaffold in the town square, and then to wear a scarlet A embroidered on her clothing for the remainder of her days. While standing on the scaffold, exposed to the public, Prynne is hectored by both the mob and the prominent members of the town, including the adored minister Arthur Dimmesdale, to name the child’s father- but she stalwartly refuses. Also while she is standing there, she sees a white man, guided in by a Native American man, enter the scene at the back of the mob. Prynne and this man make eye contact, but he puts a finger in front of his lips. After the spectacle, Prynne is brought to her prison cell, where she is visited by a doctor; this is the man she had seen at the back of the crowd, who is also, it turns out, her husband, Roger Chillingworth, recently arrived from England after having been thought dead. They have an open and amiable conversation about each of their shortcomings in their marriage, but when Chillingworth demands to know the identity of the child’s father, Prynne continues to refuse to reveal it. Upon her release from prison, Prynne and her daughter move to a small cottage on the edge of the town, where she devotes herself to needlework (producing work of notable quality), and helping others in need as best she can. Their isolation eventually starts to affect Pearl’s behavior, as lacking playmates other than her mother, she grows into a rambunctious and unruly little girl. Her behavior starts to attract the townspeople’s attention, so much so that members of the church recommend that Pearl be taken away from Prynne in order to receive better supervision. This, obviously, greatly upsets Prynne, who goes to speak with Governor Bellingham. With the governor are the town’s two ministers, and Prynne appeals to Dimmesdale directly as part of her argument against the townspeople’s motions. Her plea wins him over, and he tells the governor that Pearl should remain with her mother. They return to their cottage as before, and, over the course of several year s, Prynne begins to earn herself back into the town’s good graces through her helpful deeds. Around this time, the minister’s health begins to worsen, and it is suggested that Chillingworth, the new physician in town, take up residence with Dimmesdale to watch over him. The two get along at first, but as Dimmesdale’s health deteriorates, Chillingworth begins to suspect that his condition is in some way the manifestation of psychological distress. He begins to ask Dimmesdale about his mental state, which the minister resents; this pushes them apart. One night, shortly thereafter, Chillingworth sees on Dimmesdale’s chest, while the latter is sleeping, a symbol that represents the minister’s guilt. Dimmesdale then, tormented by his guilty conscience, wanders one night into the town square and stands upon the scaffold where, several years before, he had looked upon Prynne as the town antagonized her. He acknowledges his guilt within himself, but cannot bring himself to do so publicly. While there, he runs into Prynne and Pearl, and he and Prynne finally discuss the fact that he is Pearl’s father. Prynne also determines that she will reveal this fact to her husband.  Pearl, meanwhile, is wandering around beside her parents throughout this conversation, and repeatedly asks Prynne what the Scarlet A stands for, but her mother never responds with a serious answer. Shortly thereafter, they meet again in the forest, and Prynne informs Dimmesdale of Chillingworth’s desire for revenge on the man who usurped him. As such, they make a plan to return together to England, which gives the minister a new bout of health and enables him to give one of his most rousing sermons at Election Day a few days later. As the procession leaves the church, though, Dimmesdale climbs up onto the scaffold to confess his relationship with Prynne, at which point he promptly dies in her arms. Later, there is much discussion amongst the townspeople over a mark seen upon the minister’s chest, which many claim was in the shape of an â€Å"A.† With this affair now effectively settled, Chillingworth soon dies, leaving Pearl a large inheritance, and Prynne voyages to Europe, though she returns several years later and resumes wearing the scarlet letter. At some point thereafter she dies, and is buried in the same plot as Dimmesdale.

Wednesday, March 4, 2020

Amphoteric Definition and Examples

Amphoteric Definition and Examples An amphoteric substance is one that can act as either an acid or a base, depending on the medium. The word comes from the Greek amphoteros  or amphoteroi, meaning each or both of two and, essentially, either acid or alkaline. Amphiprotic molecules are a type of amphoteric species that either donates or accepts a proton (H), depending on the conditions. Not all amphoteric molecules are amphiprotic. For example, ZnO acts as a Lewis acid, which can accept an electron pair from OH but cannot donate a proton. Ampholytes are amphoteric molecules that exist primarily as zwitterions over a given pH range and have both acidic groups and basic groups. Here are some examples of amphoterism: Metal oxides or hydroxides are amphoteric. Whether a metal compound acts as an acid or a base depends on the oxide oxidation state.Sulfuric acid (H2SO4) is an acid in water but is amphoteric in superacids.Amphiprotic molecules, such as amino acids and proteins, are amphoteric.