Monday, 30 April 2018

journals - What does "ADM" stand for on an article submission information page?


On the information page of my article submission, there's a column titled "ADM", listing the name of two persons that I can email.


What does this stand for?



Answer



In this context, ADM probably means "administrator." In other words, those are likely the people you are expected to contact in case of questions and problems with the submission site.


human biology - Why do we age? or Do we have a theory of senescence?



There seem to be a number of ideas about why we age. Hypotheses include the gradual accumulation of cell metabolic products affecting organism function and the reduction of telomere length during cell division. My hand-wavey idea would be "wear and tear".


Are we anywhere near a consensus theory of senescence?



Answer



The 'wear and tear' argument is most likely true but it is also interesting to reason about ageing as inevitable from the evolutionary point of view.


To set up the argument, we need two things: First, each individual has got a 'reproductive potential' which is realised throughout life. This means a deleterious mutation which has an effect in early life, will affect reproductive value more than a mutation which manifests itself in later life, after the individual has already had offspring. Thus selection will act strongly on genes which are expressed in early life than on those which are expressed later. For that reason, there's no strong selection against diseases such as diabetes or cancer. This argument can be applied not only to occurrence of disease but also to decay of ordinary functions of the body.


Secondly, cells in the body are constantly renewed and defects such as telomeric breaks are repaired. Mutations in the soma are taken care of by the immune system and can be in principle avoided. The fact that they tend to accumulate in later life can be explained by the first point: selection is weaker to oppose telomeric breaks and mutations in later life.


I was trying to be brief here, but there are more sides to the argument (e.g. Williams' antagonistic pleiotropy). Modular Evolution (Vinicius, CUP 2010) provides a good overview of the evolutionary aspect of theory of senescence (and many other interesting evolutionary arguments).


graduate admissions - Do non-academic extra curricular activities matter for grad school applications?


I just got into a PhD program and was asked to give a presentation to my juniors regarding grad school applications.


In my country (Asia region), people are fanatical about non-academic extra curricular activities that are totally not related to their topic (sports, debate team, run charities etc). E.g. A student with good grades and is the captain of the school's basket ball team can get picked for a mathematics PhD scholarship over the top mathematics student with zero non-academic activities. The belief is that scholars should be "all rounded".


I think the situation is different in the USA. I would like to encourage my juniors who have excellent academic records but without significant non-academic extra curricular activities to try for the USA because of this.


I understand there are scholarships like the Rhodes which do look at non-academic achievements. But is my general understanding of non-academic activities for USA PhD admissions correct?



Answer



In general. non-academic activities are not considered for admissions for schools and most fellowship programs in the US. The primary reason for this is that graduate programs are looking for people who will become excellent scholars and researchers (and sometimes even good teachers!). Success in sports and other highly non-academic activities is less likely to have significant influence in assessments of one's ability to do research, and therefore is not strongly considered.



However, there are exceptions. People can choose to fund activities however they choose, and can place whatever restrictions on the use of the money they donate. For instance, an alumnus could fund a fellowship for PhD students who play the tuba in a college marching band. While this doesn't happen often, it can be done. But typically admissions committees aren't concerned with such issues, and don't take them into account in making admissions decisions.


graduate admissions - Is it a red flag for a PhD program if their graduating students cannot find postdoc?


I got accepted to one of my top choice schools for a math Ph.D. However the graduate students there said in the past few years, the Ph.D.s before them (both pure and applied math) had quite a bit of trouble finding postdoc positions after graduating. But they are able to find nice jobs in industries.


Would this be a red flag? I know that finding a postdoc or a tenure track position in math is especially hard in the recent years, so this might not be a complete measure about their Ph.D. program.


I have also gotten accepted into another public university and the graduate students there said they didn't have much trouble finding postdocs. This one is not as prestige as the one above in term of general ranking.


I have professors that I would like to study with in both universities, and I am leaning toward the second one.


Could you give me some advice?




Answer



I'd recommend trying to gather some objective data on outcomes. For example, in the mathematics genealogy project you can search by "name of school" and "year of degree" to find a list of people who graduated in 2014 or 2015. It's not guaranteed to be complete, and it sometimes mixes together people who were in different departments at the same university, but it's usually pretty good (and sometimes easier than finding this information on math department websites).


Then you can start googling people, with "math" appended if necessary, to see what you can find. If you can't find any indication that someone is working in academia, then they probably aren't. If they are, then you can gauge how pleased you would be with such a job.


This should give more reliable data than self-reported difficulty of finding postdocs, because it avoid filtering through the departmental culture. Some cohorts of grad students are optimistic and enthusiastic, while others are more apprehensive, and it's not clear to me that this correlates particularly well with actual success on the job market.


It's also worth keeping in mind that the relevant issue is job opportunities, not actual outcomes. If one person complains about the difficulty of finding a job and another doesn't, you can't conclude anything without knowing where they were applying. (Sometimes students at more prestigious universities apply mainly to fancier postdocs, because they wouldn't be happy with less prestigious jobs.) Unfortunately, this is more difficult to gather objective data on, but I think it's a second-order effect.


graduate admissions - Path to a good grad school in math during undergrad?


I'm a high school senior about to graduate in 1 month. I have a strong passion in math, and I want to be a mathematician. What is the best path to getting into a top grad school? How many REU's should I try to do? Any publications? How about graduate level courses? Do you need a 4.0 in undergrad? I'm also self studying as much math as I can, from Artin's Algebra, Munkre's topology, and baby Rudin. How much math should I know by the time I apply for grad school? I would greatly appreciate your feedback!



Answer




Here are my suggestions, having just finished a year of graduate school in math. It's therefore mostly anecdotal and should be taken lightly!


REUs: Try to do as many as you can! You get to meet other people who like math, learn new stuff, practice struggling with research, travel a bit, and get some cash to boot. They also, of course, look good on applications.


Publications: I don't personally have any publications. I wrote a few papers during my REUs and projects, but they were only published on the REU websites. So they're not necessary to get in. However, I did have a great deal of trouble getting acceptances. Maybe a publication would have helped, but I think it's very rare for an undergraduate to actually publish a paper.


Graduate Courses: I took several of these as an undergraduate. I enjoyed them, but realize now that I should have taken them a little more seriously! I've forgotten a great deal of what I saw in them. However, I have noticed that I'm quite strong in the area I took graduate courses in compared to my peers. So they definitely give you an edge! However, don't become too obsessed with loading up with graduate courses. Three of them is quite a lot of work, if you give them justice. Since most graduate courses are graded very lightly, you can make high marks in them without putting forth as much effort as you would in an undergraduate course! (At least, this was how it worked at my undergraduate institution.)


That said, keep in mind that some of your time in college should be spent having fun, too. Don't become a math robot just yet! You have time for that in grad school. :)


Reading Textbooks: The fact you're already reading the "core" undergraduate books before even entering the university puts you far, far ahead of the curve. Many people won't learn those things until sophomore or junior year. I certainly didn't. Make sure you're doing the bulk of the exercises in those books, especially Rudin. Try to prove statements you come across without looking at their proofs. I feel that this is where most of the learning happens. You can easily read things and not understand them, so just watch out! Other than that, finish those books and then you should be set to take the advanced undergraduate/first year graduate courses at your institution.


The Math Subject GRE: I hate this thing and did very poorly on it. You'll blow the math portion of the general GRE out of the water. It's easy stuff for any math major. However, if you don't spend a little time reviewing, you can really mess up the subject test, since it's timed and covers things you might not have thought about for several years. The topics are almost completely disjoint from what a student taking graduate courses has been doing. Look at a few practice tests, identify what sorts of questions are asked, and train yourself to quickly answer such questions. Speed is key. You don't want the subject GRE to be a weak point on your application, especially since it's an easily prevented weak point.


So, do REUs, take graduate courses, don't sweat not having publications (but if you can get some do), and study for the subject GRE!


writing - What suggestions should I make when reviewing a poorly written paper?


Since I need a break from the reviewing...


Often in my field I review papers from researchers in Asia (reviews are not double blind) which are poorly written. By poorly written, I don't mean that the prose is not pleasing to the eye, that there are problems with how the writing flows, or that there are innocuous typos or spelling mistakes. Instead, the grammar used by the authors differs seriously from normal English, and often produces significant changes in the meaning of sentences.



Usually such papers are ultimately readable, but one has to go back and re-read sentences or paragraphs several times to infer the meaning (and this is with strong knowledge of the research area!), so I generally won't reject a paper solely for this reason. However, I would feel remiss in my duties as a reviewer if I didn't instruct the authors to improve this aspect of the paper. I'd like to provide helpful advice for the authors without just giving them a laundry list of the errors.


Typically I highlight a few places where I had significant trouble understanding what they actually meant to say, and suggest seeking a professional editor before publication.


Are these reasonable things to suggest?


What other suggestions can I make?



Answer



To comment on language is fair, to suggest improvements and even making corrections goes beyond what can be expected, depending on the degree of problems. There is of course a fine line between when something can be salvaged with a little editing and where things start to lose meaning. Many journals and publishers provide services (albeit often at a cost) for non-native speakers. What you can do is to try to help the author(s) if possible by providing examples and making minor corrections. But, it is not your job to be a service. You should state your opinion about the paper, clearly separating the scientific aspect (indicate if your think the science holds) and the language issue. It is particularly potent to state when the language obscures the scientific message. In the end it is the editor who should decide what must be done.


publications - What is the difference between letter, communication and journal paper?



Scientific literature has items called letters, communications and journal papers. They all seem quite similar in terms of format and content. What are the differences between them?



Answer



In physics, each category has a different length limit. Often "paper" has no limit. Typically the shorter the length limit, the more prestigious it is and the tougher the acceptance criteria. The subject matter covered by the journal is the same for all categories. Some journals also have a "review" category which includes papers which are not original research. Often a review is by invitation only.


Sunday, 29 April 2018

graduate admissions - Copied Letter of Recommendation?


I asked one of my professors whom I've known for 2 years to write a recommendation for me now that I'm planning for graduate school— about 3 years later after he left to another university. He asked for my full name, and just copied a letter from the web and sent it to me via email. I expected to get an accurate letter that highlights my strong points and improve my chances of getting to a good school; instead, I got a banal letter that doesn't set me apart from your average student, and which its copy can easily be found online.


I'm reluctant to add his name on the list of Referees in my application now, but I can't find a third professor other than him who is willing to write a letter for me.




  • Would his letter hurt my chances of getting accepted to a good school? Even if one of the other 2 letters was relatively stronger(slightly better) compared to this one?




  • Can I get a letter from a professor who didn't teach me? Or a professor from another university(a family friend)?






Answer



A professor whose idea of a good or even appropriate letter of recommendation is to copy a letter off of the internet and send it to you is a knucklehead. (That is a technical term: I am after all an academic professional. I could have used stronger language...) At least, he is in this respect: in the comments the OP mentions that he got a job at Waterloo, which is a university with a high international reputation. So he must have some other good things going for him. In the fullness of time, I have to believe that he will learn how to write a reasonable recommendation letter.


But that's not your problem. I would advise you to look at the fact that the professor gave the letter directly to you -- which is itself irregular and, in certain circles, inappropriate -- as a real blessing. He could have just sent this miserable excuse for a letter quietly to all the places you're applying to, and you would be the one (in the short term, at least) to suffer the consequences. I strongly disagree that you should work further with this guy to write a better letter. (In particular, I vehemently disagree that you should write the letter yourself. As I have said before on this site, I find that "immoral and wrong" -- a recommendation letter is a commissioned expert opinion. Looking over the opinion desired by the person you have been commissioned to evaluate and deciding whether or not it requires any modification is not how expert opinions work. But I've made my feelings on this moral issue clear enough already. Here let me push the practical side of this: as a student, you cannot write for yourself a good recommendation letter. There are components of such a letter that require expertise and personal experience that you necessarily lack.) It is time to start fresh and get a letter from a new person.


The part of your response that jumps out at me is "I can't find a third professor other than him who is willing to write a letter for me." That's the real issue here, and I hope it will serve as a warning to other students in your position. All undergraduates should be thinking -- from their first year -- about building good relationships with their instructors that will lead to multiple people being able to write them strong recommendation letters. It is all too easy to go through an undergraduate program -- even, perhaps especially, to excel at it -- while having very little contact with the faculty outside of the classroom and regular coursework. That is certainly a mistake.


Okay, though: what do you do? You ask whether someone who has not taught you in a course can write you a letter. The answer is certainly yes. You want the letter writer to (i) have stature in the academic community and in the particular area you're applying to, and (ii) have something meaningful to say about your academic background, skills, work ethic, and prospects for success in graduate school. Someone that you have done research with can speak to aspects of that as well or better as people who have taught you in a course in which you quietly got an A. In a pinch -- as you seem to be -- I would advise you to try to make contacts with people who satisfy condition (i) and try to rapidly achieve (ii) with them. Thus for instance if you've done any research at all in the field you're intending to study, you could send a paper (or code, or interesting data, or whatever) to an expert in that field and mention that you'd like a recommendation letter. This is a bit irregular, but if your work is solid, why not? I would do it.


I strongly recommend that you work harder to find the right person to write you a strong letter than to have further dealings with someone who has already proven to be hopelessly inept at the job.


human biology - In Japan, the official average body temperature is 36.0 °C. Why so different from that of Europe?


The Japanese Wikipedia states that the average human body temperature is 36.0 °C (here,"ヒト").
The statement references the data from the Japanese government.


Actually all of my Japanese friends think the same.
A body temperature of 37.5 °C is considered a serious illness in Japan, justifying absence from work.


Most other countries' sources cite 37.0 °C as an average.
Is there a biological explanation for this apparent discrepancy?




teaching - How to deal with a student who insists on getting a higher grade?


Student presentations were a part of my grading policy in one of my classes. I had a student who tried hard to get a higher grade in the class. But after his poor presentation, he persistently asked me to give him full credit on his presentation. I told him that his presentation was not good enough to get full credit. But he has persisted and persisted in asking for full credit.


The student told me that this is what he does in all of his classes. How should I deal with this behavior? He does not deserve the full credit he says he needs.



Answer



There are multiple issues here.


The first is a student persisting, pushing for higher grades. For this, you should see the link scaaahu left What to do about "grade grubbers?" If you continue to entertain this student they will keep pushing. Why would they stop? There is no cost and a chance for a gain. However, you need to be strong and clear. "You got this grade because of your performance. You want a better grade then give a better performance."


Second issue, which I think you mentioned (but I might be mistaken here) is students needing a higher grade than they deserve. I just dealt with this issue (again) this past month. The student (and even an admin on behalf of the student) were practically pleading with me saying "I really need a higher grade, I know the semester is over, and I know I did not do a good job, and I know I misbehaved in class, but could you pleeeaaaase give me a higher grade?"


When you encounter this second kind of issue remember that you are acting as a judge. Because of this, your decision is going to set precedent which will be held against you (and perhaps others) in the future. So, if you really want what is best for all students (including the one asking) then you must hold steady and show that students must do the work for the grade they want. Otherwise, they will think there is a way they can avoid the work and still get good grades and that is clearly not the signal we, as educators, should be sending.



In short, tough love and make sure they respect the educational process (don't allow them to badger you).


publications - Scientific output of researchers in industry and academia


How does the scientific output of PhD’s who work in industry compare to that of PhD’s who stayed in academia (professors, mainly). I mean, in terms of number of publications, conferences, etc.




career path - What contents should I put on my academic website?



I'm planing to setup a personal academic website. From visiting other researchers websites I have a rough idea of the things I want to put on it:


- Research interests    
- List of articles & conference contributions
- CV
- Links to affiliated institutions
- Contact information

Would you agree that this list constitutes the information an academic should put on his/her website? Is there anything else you would hope or expect to find? Would you advise against putting any of these pieces of information on the website?




How big are Mathematics research projects usually?


I have been involved in a number of large-ish research consortia usually with 10 or more groups, with each group containing 2 or more individuals. Some have originated from computer science, others engineering, and even the social sciences. In general all have contained partners from a variety of disciplines.


I'm curious as to how large mathematics research projects tend to be? Do they tend to be smaller, with individuals rather than research groups and/or subject matter experts involved. Are there any mathematical research associates out there that could offer insight into this please?


EDIT: Just to clarify, if P is a project, the "size" of P I'm interested in is:


|P|=Total number of people involved.

Answer



It depends on what you mean by "projects", but there are both large and small ones.



There are both casual collaborations between two or three individuals, which translate to a single paper, and which can be funded individually (there are grants as small as 1k USD or less, the money for a single visit or a conference participation), and larger ones that can let you hire multiple people for several years (e.g., the EU grants called ERC, which can give six-digit amounts).


I have also seen even larger "projects", but they were usually structured as mini-funding agencies, giving out their funding to smaller individual research endeavours.


Saturday, 28 April 2018

citations - I have two papers in an up-coming conference. Is it appropriate to cite one in another?


I had two papers approved for a workshop in a IEEE conference and I'm going to send the camera-ready version soon.


Is it OK to have one paper cite the other? If it's OK, do I have to reference the other paper as "to appear"?



Answer



This is acceptable, and fairly common. You cite as usual, and the citation itself would be identical to a standard citation with the exception that the date and page numbers would be replaced by the phrase "in press".


From the American Historical Association's "Professional Standards" page:



The AHA suggests the following lexicon.




  • "In Press": the manuscript is fully copyedited and out of the author's hands. It is in the final stages of the production process.

  • "Forthcoming": a completed manuscript has been accepted by a press or journal.

  • "Under contract to . . .": a press and an author have signed a contract for a book in progress, but the final manuscript has not yet been submitted.

  • "Submitted" or "under consideration": the book or article has been submitted to a press or journal, but there is as yet no contract or agreement to publish.



career path - How do I deal with postdoc acceptances that come in before my preferred institution makes its decision known?



I will graduate soon from the doctoral program. I will apply for multiple postdoc positions. The results of the one that I really think is great for my career will be probably announced later than the others. If I accept an earlier offer, and later learn that I could also get the one I desire the most, then I will really regret. However, I don't want to risk by refusing an early offer, since at the end I may get nothing.


Do you have any recommendations for such situations? Have you ever experienced this dilemma? How did you manage it?



Answer



This is an typical situation in application process with no perfect solution available. I is totally ok to apply for several positions at a time. The institutions are also talking to several applicants in parallel. But after signing a contract, it is not a nice gesture to revoke this w/o reason (even if notice periods would allow this legally). The institute has set trust in you and canceled the application of others. How would you feel if, after you have signed at an institute and canceled other applications, they would say : "Oh sorry, we got the confirmation from somebody which is more suitable to our business targets. Thanks for your time and good luck."


Below are some ideas on how to handle the dilemma. It is up to you, which one you want to follow:




  • Accept that in life you have to make decisions at time when you don't have all pros and cons available. It's is not like finding a solution to an exam, where the data available clearly defines which answer is correct and which is wrong.





  • Accept that, even if if you would have all offers available at the same time, you cannot say which offer is the best. Many unexpected events might happen at one position or the other: Your project might get canceled during your work. Your professor might change department. You might meet your future spouse.




  • If you are really sure which is the best position for you, but the confirmation from this position has still not arrived: Contact this potential employer and explain your situation. You are really interested in this position, but you have also agreements from other institutes so you need to make about the alternatives an decision. Is it possible for your target employer to give you an confirmation earlier? If the employer is really interested in you, they will try to shorten the decision time. Otherwise there is the risk that they lose you.




  • After signing a contract, withdraw all applications to other institutes. So you save them work. Additionally you avoid you dilemma, when you get an positive reply, but have signed already elsewhere.




  • Attention: Only be sure to have a job after you have signed a contract. Don't rely on verbal promises only. Things might change easily: The project start might be delayed by 1 year. Or the nephew of the CEO might be interested in the position ...





  • Asking for time (e.g. 1 weekend) to think it over an recent contract is ok. But at durations longer than 1 week, the employer might become impatient.




  • A bit more time can be gained, if you ask for some small modifications on an proposed contract. The employer might need some time (eg. 1 week) to issue a new contract. Anyhow this point (and the previous one) shall not be exploited too much. The employer might get the impression that you are not really interested and hire an other candidate in the meantime.




  • If possible, you can try to reduce the risk a bit, by smart timing of the applications. First send them out to one or two institutions which are not in your main target area. The benefit here, is that you have the opportunity to get some more training in the application process. You become more confident in interview situation. Second try your number 1 choice. You can hope for earlier feedback if there is an opportunity for you. With some delay you could contact departments which are a good fallback solution, althrough not the main target. The idea here is that you are not forced to early to decide to take or leave an offer here. If your number one declines, you might get some positive feedback from these good fallback solutions later. Of course this strategy has to be adapted to time restrictions, and the application deadlines for the adverticed positions.





  • Career is not only defined by your first job. Of course this first job already gives you an direction in industry you will develop. Further corrections here might be energy and time consuming. But the final result, if you become an owner of an multinational enterprise, an university professor, or simply an employe w/o significant career step depends mostly on personality.




  • Potential employers prefer candidates who appear to be authentic. Don't try to play to much games with them.




  • Trust your gut feeling.





genetics - Are there multiple meanings to "clone" as in "clone a gene"?


I originally thought that cloning a gene meant to put it into bacteria and have them express it. But sometimes I see it used and it seems like it's just a synonym for "identify the sequence and/or location of". So what does "clone a gene" really mean"




Friday, 27 April 2018

nutrition - Is there evidence to suggest that nutrients in vitamin capsules are not as readily absorbed as the same nutrients in whole foods?


I recently fell ill with a cold, and began to take a vitamin C capsule each day to help my immune system. When I noticed no change in my condition, I began to incorporate an abundance of citrus into my diet instead of taking the capsules. When I ate the citrus my condition began to improve markedly.


The ingredients listed by the vitamin manufacturer are:



  • Ascorbic Cellulose Gel

  • Hydroxypropyl Cellulose


  • Croscarmellose Sodium

  • Stearic Acid

  • Magnesium Stearate

  • Silicon Dioxide


Not excluding the possibility of coincidence, I was was intrigued. Has evidence been published to suggest that nutrients in whole foods like vitamin C in citrus fruits are more readily utilized in the body than nutrients in vitamin capsules?



Answer



Vitamin C bioavailability


According to the review Synthetic or Food-Derived Vitamin C—Are They Equally Bioavailable? (Nutrients, 2013), the bioavailability of vitamin C from foods and supplements is similar:




...all steady state comparative bioavailability studies in humans have shown no differences between synthetic and natural vitamin C, regardless of the subject population, study design or intervention used.



and, according to Institute of Medicine (in the US):



The type of food consumed has not been shown to have a significant effect on absorption of either intrinsic or supplemental vitamin C.



Vitamin C supplements as prevention for common cold


Vitamin C supplements, even in doses 200+ mg/day (more than 3 x recommended dietary allowance - RDA) do not likely help in common cold:



This review is restricted to placebo‐controlled trials testing 0.2 g per day or more of vitamin C. Twenty‐nine trial comparisons involving 11,306 participants contributed to the meta‐analysis on the risk ratio (RR) of developing a cold whilst taking prophylactic vitamin C. The failure of vitamin C supplementation to reduce the incidence of colds in the general population indicates that routine prophylaxis is not justified. Vitamin C could be useful for people exposed to brief periods of severe physical exercise. (Cochrane, 2007)




To get 200+ mg vitamin C from citruses, you would need to eat at least 3 oranges or 7 lemons.


Considering the above evidence, the improvement of cold symptoms was likely a natural process.


Bioavailability of other nutrients from foods/supplements


There is no general rule to say that nutrients from foods or supplements are absorbed better or worse; it can depend on a specific food and a specific supplement formulation.


Iron:



In our in vitro model, naturally iron-rich mineral waters and synthetic liquid iron formulations have equivalent or better bioavailability compared with ferrous iron sulphate tablets. (European Journal of Nutrition)



Iron-fortified foods:




Bioavailability of fortification iron varies widely with the iron compound used (56), and foods sensitive to color and flavor changes are usually fortified with water-insoluble iron compounds of low bioavailability. Iron compounds recommended for food fortification by the World Health Organization (WHO) (56) include ferrous sulfate, ferrous fumarate, ferric pyrophosphate, and electrolytic iron powder. Many cereal foods, however, are fortified with low-cost elemental iron powders, which are not recommended by WHO (57) and these have even lower bioavailability (AJCN, 2010).



Magnesium:



The results of serum and urine analysis indicated that Mg bioavailability was comparable for mineral waters with different mineralization levels, bread, and a dietary supplement. (Tandofline, 2017)



Mg supplements comparison:



Studies on the bioavailability of different magnesium salts consistently demonstrate that organic salts of magnesium (e.g., Mg citrate) have a higher bioavailability than inorganic salts (e.g., Mg oxide) (Nutrients, 2019)




Potassium:



The bioavailability of potassium is as high from potatoes as from potassium gluconate supplements. (AJCN, 2016)



In conclusion, even if most studies mentioned in this answer suggest that nutrients from foods and supplements are equally bioavailable, you need to check specific supplement formulations, for example, iron from many fortified foods and magnesium oxide can have poor bioavailability. Anyway, the studies show that most people with normal blood nutrient levels do not need dietary supplements (Int J. Prev. Med., 2012 ; Annals of Internal Medicine, 2014).


phd - Boost grad apps profile without getting a second master's: Subject GRE? Self-study? Soft skills?


In general, how does one boost PhD admission profile?


In my context, same question but besides getting a master's in pure math. (See here and here)


Here's what I got so far:




  1. Employment not specifically in research for soft skills boost (I have specific career goals in case I am not good enough for academia)

  2. Employment specifically in academic research (I've seen job posts that look for research assistants) for research experience here I think?

  3. Employment as a research analyst in finance

  4. Tests e.g. GRE Subject

  5. Self-study




What else?





  1. work for a professor for a research project like here I think?




  2. Or pay a professor to supervise my own research projects like here I think?






My context:






What about the GRE Subject?



  • I was suggested by one of my professors to study for GRE Subject, but I think that was in the context of his applying to master's having had only a bachelor's.


On one hand:



  • The GRE Subject may make up for low grades or the fact that I haven't had complex analysis, number theory, graph theory and abstract algebra. Is that right?


On the other hand:




P.S. Sucks if I don't stand a better chance for boosting admissions through self-study. Sigh. Can't believe there's a dichotomy between doing what is helpful for graduate school and what is helpful for graduate applications, but then again professors aren't the only stakeholders.




publications - Should the PhD supervisor's name be first in a scientific journal?



I am a self funded PhD student and have been told by my supervisor that her name should be first on any future journal I will be publishing during my studies under her supervision as "this is the only thing she gets from her PhD students".


I am just wondering if the ordering of author names matter? She is going to help me only by proof writing my article. All research will be done by myself.


Is she legally allowed to say it? Should I accept it?




work life balance - Advice for having children during graduate school


My wife and I just found out that we're having our first child. While this is a wonderful thing, it also concerns us a bit. Particularly because we're on limited funds (TA & RA combined salary) and we're still 1.5-2 years away from graduating together. Also, since our academic careers are so demanding, we're also concerned about balancing time taking care of our newborn.


I read the responses in this post, but I'd like to ask for more specific advice for new parents in graduate school. What strategies have you used to enable you to handle having a newborn while both parents are finishing their PhD? Both in terms of time management and making ends meet, financially.



Any personal anecdotes, experience, advice, and tips are welcome! :)




university - How does a faculty member get to work at two universities or more?


This question is a follow-up on a comment at a recent question, where Dave Clarke mentioned that an acquaintance of his has "3 professorships and 2 doctorates".



  • How does a faculty member get appointed simultaneously by two or more universities? Are all except one honorary posts?


  • Can any faculty member work with a second university with the consent of his present employer? What are the conflicts of interests that come into play usually?



Answer



The situation I've seen most often is that a professor will hold a primary appointment at school A, where they have a lab and complete their research. Often for reasons related to collaboration, school B will then give the professor an appointment in a related if not identical department. If the professor also teaches a few courses at school C, they will likely be granted an adjunct position there as well.


This was my setup when I was in graduate school; I was a grad student in bioengineering at U Pitt, and I had a secondary appointment at CMU due to both lab collaborations and my being registered in a certificate program there.


books - How much does it cost the publisher to transform the draft of a textbook as given by the authors into a final publication (for web or print)?


I wonder what are the actual costs of translating a manuscript of a textbook as given by the authors into a final publication (for web or print). I.e., ignoring the costs of marketing the textbook, and printing the textbook, and serving content via web.


I am mostly interested in the fields of computer science and maths, English-speaking venues, and the United States, but I am curious about other fields, languages, and countries as well. I am looking for referenced numbers, not guesses.




Given the number of downvotes and close votes from people who seem to think it's impossible, here is an example



Answer




The costs are going to depend on three factors: (1) how long the book is, (2) how well written the book is, and (3) how much layout work the publisher does.


For example, in Math, the publisher might provide a LaTeX template and expect you to hand tweak underfull and overfull lines, float placement, and hypenation. In other fields it is more typical to give the publisher plain text with minimal markup.


The Editorial Freelancers Association publishes recommended editing fees. A typical book might have a round of "line editing" at 4 cents per word, a round of layout at 4 cents per word, and a round of basic copy editing at 2 cents per word.


If the book is poorly written, two rounds of line editing might be needed. If there is automated layout, the layout costs could be saved. There is also the cost of creating an index at 2 cents a word, which depends on who makes the index.


Thursday, 26 April 2018

immunology - Doubts regarding definition of upstream/downstream genes and cognate protein


With respect to the research paper, there are a few things I didn't understand:

1. What is upstream and downstream gene
2. This paper identifies proteins that help in secretion, but does not identify the originally secreted protein. Am I correct?
3. Does cognate protein here mean homologous protein(from common parents)?



Answer



Upstream means towards 5' direction from the reference point (conversely for downstream). Reference point can be a single position such as transcription start site (TSS) or a bigger segment such as a gene. When we say upstream of a gene, it means some region of DNA that is towards 5' direction from the TSS of the reference gene. Downstream of a gene refers to the region 3' to the transcription termination site of the reference gene.


Similar terminology is applicable to RNA but obviously, in this case your reference cannot be a gene (it can be an exon, for instance). I have not seen this terminology used in case of proteins.






enter image description here




This paper is about identification of the proteins that aid in secretion (TEC) of certain proteins (effectors). They identified both the proteins that help in secretion and the proteins that are secreted



Here, we report a class of T6SS effector chaperone (TEC) proteins that are required for effector delivery through binding to VgrG and effector proteins. The TEC proteins share a highly conserved domain (DUF4123) and are genetically encoded upstream of their cognate effector genes.
[....]
We validated this approach by verifying a predicted effector TseC in Aeromonas hydrophila. We show that TseC is a T6SS-secreted antibacterial effector and that the downstream gene tsiC encodes the cognate immunity protein. Further, we demonstrate that TseC secretion requires its cognate TEC protein and an associated VgrG protein.



Cognate refers to the correct binding partner which will result in a functional complex. It basically refers to biomolecular partners with a known and validated relationship. This relationship need not be synergistic. For example:




RNA interference (RNAi) is an evolutionarily conserved process through which double-stranded RNA (dsRNA) induces the silencing of cognate genes. (Source)



productivity - How to make good use of compulsory study plans in connection with PhD studies?


I am not sure if this concept sounds familiar to you but in Sweden PhD students are expected to have a study plan, which is revised every year, in connection with a meeting between the student, the primary and secondary supervisor(s). It's the closest thing I have to a contract actually.


Theoretically the concept is great, there's a formal demand to plan and revise the projects, so that things don't get out of hand. The study plan typically defines:



  • the nature and title of graduate studies

  • an expected time of dissertation

  • the responsibilities the student has towards the department (teaching, lab/IT responsibilities etc)

  • the extent of research/course ratio per semester


  • courses taken/planned

  • the project that planned to/will be a part of the thesis


Then comes a series of so-called "lärandemål" which I could possibly translate as "learning goals" mandated/advised by the board of higher education services (Högskoleverket) and what is planned/completed to achieve these goals. This piece constitutes a majority of the study plan essentially.


So far so good... I think conceptually it's a great idea. In practice, the part regarding learning goals becomes a whole bunch of formal gibberish that does not reflect reality but looks fancy on paper. My supervisor does not really care much about the plan, at least not in the format it's forced on both of us. I am not sure if this is the impostor syndrome speaking, but I feel like it's essentially an annoying piece of paperwork, on which I am forced to write what I am doing/have done in rather exaggerated fluffy words. I have also considered the possibility that I perceive it thus because even though I am very fluent, Swedish is not my first language. I could not say for sure...


I am trying to force myself to see the benefit in having and updating such a study plan. I could just do the minimal amount of work and get it over with, but seeing that this is actually my chance and legal right to influence the development of my graduate studies, I feel it'd be a waste of opportunity if I did not take the chance to make the best out of it.


Any ideas as to how I can make better use of these study plans and study plan meetings that go along with it? Likewise any plans as to how I can avoid seeing it as an annoying piece of work that has to be done and have no practical meaning?



Answer



I can sympathise with your sentiment about the study plan. The idea is generally good but it will only be as good as one makes it. In my department we started with study plans long before it became a mandatory requirement. The reason was mainly to establish a contract (although strictly speaking it has no legal meaning) where student and advisor agree to the terms of the work. We had instances where both students and advisers were not doing their part and lacking a paper trail made discussions difficult, usually both parties blaming each others for the catastrophe that emerged when it was too late.


So, I still look at the study plan as a tool when things go wrong, actually to identify when things start to diverge and nip it in the bud. There are students who do no appreciate the plan but as subject responsible (and in our case the discussion involves also me) I try to make it a good and reflective discussion. I do believe it is good to take the opportunity to reflect upon what has been done so far and try to lay out the plans for the next year because in a PhD project the nose is often close to the work and perspective may be difficult to get. Providing an opportunity to express the plans can therefore be enlightening for all parties.



I must, however, add that the bad cases which the study plan is supposed to reduce, still are very difficult and the study plan is not enough to resolve such cases. So my recommendation is to try to find a format for the discussions so that they become useful and positive for you. I would not expect everyone to experience these discussions the same way so in the worst case, try to make it as pleasant as possible.


EDIT in response to comment. As with most things that are forced into action from "above", the way to handle study plans and how to relate to them has become unclear. I can personally see that different departments view the document differently and although the Science faculty of my University has issued guidelines, my suspicion is that they have no clue what they are trying to say. So it is all confusing.


Now, recently I heard a lecture by Bob Harris at the Karolinska Institute, Stockholm which concerned the so-called Intended Learning Outcomes (ILOs; another fancy term). You can listen to a talk similar to the one I attended on BrainShark, however, a warning is issued for the poor sound quality. The talk was for director's of graduate studies and the Faculty. The point made here is that we need to decide what it is that we do during a PhD and it is only then [my interpretation] that we can make use of the study plan to see if we meet the expectation from the side of the Higher Education Act as well as from our personal viewpoints. All of this becomes very involved and I am myself in the process of changing the way we look at the study plan to also include the goals of the research education as formulated in the Swedish Higher Education Act.


A problem with study plans as they stand now is that everyone must be involved in the process and as with everything else, they are not necessarily so and opinions will vary. Some will find it very useful and some will not. If a study plan is merely a meeting where one says 'done that; will do this' then its use is very limited. At best it is a time to actually reflect upon the progress or lack thereof. In the end, I think we have all lost track of the purpose of a PhD, we do not see the forest for all the trees. Publish has become the (only?) goal but all the other skills are not highlighted well or even considered. Integrating the wider goals with the study plan to record and view progress, could in my opinion be a useful tool but it requires more or less reorganisation and additional adaptation by many.


Non-citation of basic knowledge


We all know how important proper attribution of ideas is. At the same time, certain things have become basic enough that citing the paper where they were first discussed is overkill: to give an extreme example, if you need to do some differentiation in your math/physics paper, you don't need to go and cite Newton and Leibniz. Now, on occasion students ask me how one can determine if a piece of knowledge is common enough that they can forgo a citation. The rule of thumb I give them is:



If it is something that is explained in a standard first-year undergrad textbook, then anybody who is going to read your papers knows about it and you don't need to provide a citation.




[Here I want to emphasize that I give this to them as a rule of thumb, and I always tell them to ignore it and provide the relevant citation if they think it is necessary to do so in a specific case]


Are there better or alternative ways of drawing the line?



Answer



I find Latour and Woolgar's spectrum of "facticity" a useful tool for thinking about these questions (a nice summary can be found at this link). It breaks scientific statements into five rough categories by level of certainty in the assertion:



  1. Speculations - don't have to be backed by anything

  2. Descriptions - not established, so need to be directly backed by evidence

  3. Tentatively established - need to be backed by citations

  4. Well accepted - should be stated, but don't need evidence or citations

  5. Tacit - should not even be stated



Where exactly a fact lies on this spectrum depends on the community and state in discussion. In general, the broader the audience, the less well accepted facts should be assumed to be. I think the notion "Should everybody reading this have been taught in a class?" is a good one, though undergraduate is not necessarily the stopping point. For a machine learning audience, for example, you should assume everybody has had graduate level machine learning courses, while for a biology audience you should not assume they have even had undergraduate computer science.


Wednesday, 25 April 2018

mathematics - How can an undergraduate student conducting mathematical research with a professor expect to contribute?


I am currently an undergraduate student majoring in Applied Math. I have been reading recent papers published by two of my professors who I admire and I'm wondering what it would be like to conduct research with them. In what ways can an undergraduate student contribute to mathematical research? In what ways could I prepare myself to conduct mathematical research?


To be more specific, my academic background is in History and Social Sciences which I studied intensely from High School through my first two years in college. I conducted research at University of Arizona my junior year of high school analyzing a large set of longitudinal data on a group of high schools in NYC. My interest in math, specifically applied math, started when I took a Computer Science class because I was curious. Since then, I've taken calculus courses, applied combinatorics, probability courses, and I'm currently enrolled in a computational geometry course and an operations research course. The reason I'm interested in pursuing undergraduate mathematical research is because I enjoyed the experience a lot when I was studying social sciences. My concern is that I don't have a strong enough background to contribute to the research my professors currently conduct. I get good grades in my classes, but I'm concerned with my lack of background for a Junior in an applied math major. Recent publications from my professors are difficult for me to understand, so I'm questioning whether I'm ready to conduct research with them. I'm hoping you may be able to offer insight into whether my background is sufficient for conducting research and how I may be able to strengthen my skills. I take my school work seriously and think I have a good understanding of the material I'm taught. Thank you for your time.



Answer



It's very reasonable to wonder how you, an absolute novice, could "help" experienced experts. Some people are fond of claiming that somehow "just trying hard" or "being smart" can make this possible in some way, but those are needless (and doubtful) claims that miss the mark about what the real question could be.


That is, many or most faculty are happy to mentor beginners and introduce them to the subject(s) the faculty know and like. It need not be the case that they "need help", and, if they did, sure, recruiting novices is not the best gamble. But that's not the point! The point is that experts may enjoy (and find stimulating) introducing beginners to their subject. So you help them by allowing them to do so.


It's not at all surprising that you have trouble reading their recent papers, and, again, that's essentially irrelevant. (The internet mythology about young people becoming world experts in a few weeks or months is invidious... In particular, no, you should not expect to "read those papers and then go talk to them about them.", contrary to much advice given on-line.)


An astute expert can find interesting "starter" projects for novices. It may happen that such a project produces something interesting to the expert. Or, it may be that the expert can so well foresee the outcome that the element of surprise evaporates. But that doesn't matter. Little kids don't have to immediately play sports (or whatever) with world-class professionals. But they can be coached by such professionals, if both parties are interested. I do think that's the correct analogy, though many other people on these sites are adamant otherwise.



job - Academic Hiring Process and Practices for Junior Professors in Germany


I am being considered for a job in Germany (W1 junior-professorship) and I was hoping to get some insights regarding the process as I come from the US system and am unfamiliar with how things work in Germany.





  1. I notice that the application packages do not require inclusion of recommendation letters. In the US, the typical requirement is that the application package includes at least 3 letters. Will the schools require recommendation letters once selected for an interview or the job? Do letters or references play any significant role at all?




  2. Selection: I know this should vary by case, but how many people do they tend to put on their short list?




  3. Interviews: I get a feeling that the interview process is brief and a lot less tiring than the American system (for a R1: Typically a 3-day campus visit, job talk, endless meetings with professors, deans, grad students, teaching demonstration, etc, etc). What do they focus on in Germany? (I am asking this as I was invited for an interview, but I was not even asked to do a job talk or teaching demonstration) Are there typically multiple rounds of interviews?




  4. Selection committee: That some European departments practically have a one-person decision making body came as a surprise when I first came to Europe. How is the case in Germany? How many people in the department are typically involved in the decision making process?





  5. Final decision: How fast do they move with their final decisions? For example, the job I am considering only has about a four month gap between application deadline and position start date. This is significantly shorter than a typical US-Search where many schools begin examining applications a year before the position start date, and tells me that they should be moving fairly fast with the decision. Any inputs?




I know these might be a lot of questions. As someone unfamiliar with the system, I am hoping to gain as much insight as possible.




Books for beginners




I want to study biology. I have zero previous knowledge of biology but I know Physics, Chemistry and Maths. From which book should I start? I have heard about Campbell Biology, but it is very costly in India(more than my 1 month's earning). So please suggest books that:



  • Are cheap OR could be found on internet


  • Require no previous knowledge of biology

  • Contain no technical mistakes

  • Adequately explain the topics which they deal with

  • and also mention some history of the topics


Edit


I am not looking for online videos. I want books; my internet is slow and there are some other problems. You can also tell costly books--Perhaps I could find them in the library or could print it somehow. If Campbell Biology book is available online then please give me the download link.




journals - Reviewer makes an obvious and serious mistake and paper is rejected


Long story short: Submitted a paper to a very respectable (but not TOP) journal in the TCS community. Received 2 reviews. The one was alright, not extremely enthusiastic but a decent review.


The problem is with the 2nd one: The reviewer failed in the most obvious way to even understand the statement of the problem, and said that "I cannot convince myself that the paper is correct". The misunderstanding is on the definition of the problem.



for the TCS people: its a standard resource allocation problem where we want to optimize some objective function. The reviewer's objection is that if we assign the same item multiple times to different users we could achieve a very different objective value thus the analysis on its bounds we give could not possibly be correct!


This does not any make sense since on the definition it is said explicitly that each item must be assigned once. In any case, it's the most standard definition of a very well known resource allocation problem!


Anyway, after the rejection of the paper based on the above reason, I contacted the Editor in Chief of the journal, asking for a 3rd reviewer to resolve the issue (I was not offensive to the 2nd R). The EiC responded immediately saying that a 3rd R could indeed resolve the issue but there is nothing the EiC could do because the handling editor communicated to the EiC that the Com. Editor trusts the expertise of the reviewers, and thus the rejection decision is irrevocable.


I want to ask:



  • How normal is this situation? We are talking about an old and very well respected TCS journal, not some hocus pocus unknown journal.

  • Is there any safety net for such kind of obvious mis-managed cases?

  • Any particular advice for the incident? I am not very interested in the obvious "deal with it, it happens" answer. But observe that I am in a point of my career that an extra journal publication could mean a lot, since I am trying to find a permanent position and I cannot wait another year for this paper to go through such a process.


Note: I see few people misunderstood my comment. My comment is not targeted to the reviewer who might have made an honest mistake. It happens and I do not blame her/him. My point is mainly on the way the journal handled the situation, even when the very serious and very easy mistake was brought up to their attention. I was mainly interested if such a reason is valid for straight rejection (usually there is some revision needed which we have the chance to explain to the reviewer and the editor where they have been mistaken), and what to do when this happens. As mentioned again, I do not have 30 journal papers so that I could say this won't make any impact in my CV. I am applying for permanent positions and a +1 (very good) journal might make some difference. Thus my main question: is there any safety net that prevent non-professional editors make such unjustified and arbitrary decisions with such huge impact on us? And how this affect only us as authors? Is there any way to make journals (in general) act more professionally (without making a war against them): sadly, from the comments below, I guess not, besides boycotting the journal, but they couldn't care less.





virus - Why does rabies cause hydrophobia?


What feature of rabies pathophysiology causes hydrophobia? Why is hydrophobia unique to this one particular type of viral infection?



Answer



Rabies causes hydrophobia in the encephalitic stage which means when it affects the brain and causes swelling and inflammation of multiple areas of the brain. Hence, it affects the complex areas in the brain needed for swallowing. Initially into the course of the disease, the patient has involuntary contractions of neck muscles when he drinks water. At later stages of disease, the patient starts contracting his muscles even at the thought of water. Rabies virus is a neurotropic virus which means that it travels through nerves because of its preference to attach to acetylcholine receptors in the neurons. That is how the virus spreads from the bite site to the brain(via the nerves).


teaching - what is the best strategy to deal with a situation where a student asks all of homework problems on an online forum



I teach a course, every week I assign homework. I put several hours to choose the right homework problems which cover the course material and permit them to be prepared for the exams.


I encourage students coming to my office hours and to ask all of their questions, I may also help them to solve the homework problems. During the class I normally give some hints about the homework's difficult problems (in any).


The homework load is (in my opinion) reasonable: 4-5 exercises, maybe 3-4 out of them are easy and maybe 1-2 is a little challenging. The homework has 10% point.


Today, to my surprise I saw a user who has asked all of my homework problems (including the easy ones) on math stackexchange. And all of them have been answered. Regarding the particularity of my homework problems and the time of posting the questions, I am sure that the user is one of my students, I am not sure which one.



To be precise I had not prohibited the students about posting the homework questions online as I was not expecting this situation.


My question is what is the best strategy to deal with this situation.




human biology - Determining a patients biological age?


I am looking for an algorithm that shows the exact coefficients some variables that have on a hospital patient's chronological age versus their biological age.


I understand a lot of the variables that go into determining ones biological age (i.e. Blood pressure, diet, family history of disease, obesity etc.) but not the amount of impact that it has on the actual scoring of their age.


I have found many sites that will calculate it, however I need the actual variable coefficients and influence in order to produce a proper score for thousands of patient records.


Thanks in advance for your input!



Answer



As the definition of biological age is very ambiguous, I propose that to generate an algorithm, you first need to create a quantifiable definition. I submit:



Biological age is a measure indicating what portion of one's calculated life expectancy is already expended, adjusted proportionately for the average life expectancy of their major demographic.




Wow, that's a mouthful! So, let's break it down.


Life expectancy is calculated :



  1. Ascertain a person's major demographic (Geographic residence, Race, Gender and Generation).

  2. Find the average life span of that demographic.

    • This is negligibly speculative as a living person's Generation has not yet fully perished

    • Statistical outliers, such as infant mortality, are generally excluded from this calculation




  3. Adjust for known major factors that have accepted statistical impact.
    eg:

    • Lifestyle

    • Current medical conditions

    • medical history





Average Life expectancy of subject's demographic was calculated in #2 above.




So, now let's throw in some sample numbers.

Statistical Facts: (totally made up)



  • Caucasian males living in the France, born in the 1970s have an average life span of 72 years.

  • Exercising 30 minutes or more daily increases life expectancy 6 years

  • Smoking decreases life expectancy 7 years

  • Not smoking increases life expectancy 2 years
    Hold on a second?! Wouldn't not smoking already be accounted for in the "Smoking..." section? Well, no, because our demographic sample are all "unknown" so having specific knowledge would statistically change the results in either direction


  • Heart Disease decreases life expectancy 8 years

  • Devout religious affiliation increases life expectancy 6 years.

  • Family history of diabetes decreases life expectancy 2 years.


Two subjects both Caucasian, french males born in 1974 (40 years old chronologically):
Their mom's actually shared a labor and delivery room!



  1. Beavis - known: Smoker with heart disease.


  2. Butthead - known: Devout Buddhist, very athletic, non smoker with a family history of diabetes



    Beavis' life expectancy is 57 (72-7-8)
    Butthead's life expectancy is 84 (72+6+2+6-2)


    Beavis has expended 70.2% (40/57) of his life expectancy
    Butthead has expended 47.6% (40/84) of his life expectancy


    Despite sharing a birthday:
    Bevis' biological age is 50.5 years (.702*72)
    Butthead's biological age is 34.3 years (.476*72)




Note: It's almost 6 hours past my bedtime, so please excuse any stupid mistakes or miscalculations. The general concepts are what is important



Tuesday, 24 April 2018

titles - Can I call myself an assistant professor without a PhD?


I've recently gotten a job as lecturer and economics course module developer at a new university this fall. The position is intended as permanent. There is opportunity for funded research but that isn't an objective of the chairs due to the newness of the university.


What is strange is that the position is called "Assistant Professor" which makes no sense due to the size of the institution and the lack of research required by it (It is a private university).


I am currently enrolled in a PhD program but have some time to defend my thesis. I'm wondering if it's fair to call myself an "assistant professor" or not being that I haven't been endowed with my PhD yet.



Answer





the position is called "Assistant Professor"



If you hold an appointment as an assistant professor, then you are an assistant professor. Still, I understand your concern....



kinda makes no sense due to the size of the institution and the lack of research required by it...however this is a bit of a no-name brand institution



Context is everything.



  • I agree it would look foolish or pompous if you use your title in a way that gives the impression you are a professor at an R1. When meeting colleagues at different institutions, you may wish to describe yourself as a lecturer or say "my title is assistant professor, but it's mostly teaching" or something unambiguous like that.

  • On the other hand, everyone at your home institution should understand what an "assistant professorship" at that institution entails, so there is no issue with you using the title internally.


  • Similarly, non-academics don't know or care about the subtle differences in academic rank, "I'm an assistant professor" is fine in such contexts.


Regardless, your PhD (or lack thereof) is irrelevant.


Sadly, such overloaded terms in commonplace in Anglophone academia. Many of us with doctorates select the salutation "Mr./Ms." to avoid being confused for an M.D. ("real doctor"). Those with PhDs from online schools face a similar dilemma.


human biology - What is happening when we get a tan?


Almost everyone nowadays wants that nice summer tan, but what exactly is going on beneath the skin? I've heard a few different theories about tanning - such as a tan is nothing but the pigmentation in your cells burning, but is this true?


My questions:




  • What exactly is happening to our skin as we tan?

  • Are pigments being burned (like I was told in school), or is pigment being produced by the cells. ?




Bonus related question: Why do some people burn and others tan?


Bonus related question: https://biology.stackexchange.com/questions/35719/how-does-our-tan-disappear



Answer



When our skin is exposed to the sun, this can cause some damage in the upper layers of skin. This activates DNA damage repair and also induces signalling towards the melanocytes (which produce the pigment). Signalling means the excretion of signalling molecules (mostly alpha-Melanocyte stimulating hormone, aMSH) which binds to the MC1R receptor (melanocortin 1 receptor) on the surface of the melanocyte (the cell which produces the pigment) and induces (or increases) the production of melanin. The melanin is then transferred in the melanosomes to the adjacent keratinocytes, which are then better protected from the sun. This figure (from this article) illustrates this process nicely:


diagram of UV effects on the cellular level



Short term tans (the fast reaction) are based on the changed distribution of melanosomes (granules containing pigment) from the melanocytes to keratinocytes. Longer term suntans are caused by increased pigmentation in the skin as a reaction to the UV exposure by the accumulation of melanin and by the burning of cells. So it is no wonder that it looks like increased pigmentation, it really is. People tan differently because of their genetic background. This influences their ability to react to sun exposure.


There is relatively little known about the degradation of the melanosomes (the granules containing the melanin). What is known is that they are degraded in the lysosome, and that the melanin is most likely degraded through oxidation. There happens to be a permanent turnover of the melanosomes, and when the body is producing fewer new melanosomes than are degraded, your skin will get lighter again.


References:



  1. Shining light on skin pigmentation: the darker and the brighter side of effects of UV radiation.

  2. Melanocyte biology and skin pigmentation.

  3. Melanosome Degradation: Fact or Fiction


Social etiquette for interacting with PhD peers who complain *a lot*


People in my program complain a lot and usually not in good humor. How can I handle this socially and professionally?


Some of these people are my friends and some are no more than peers. In general I want to be respectful but not allow them to harangue me with complaints. Generally, much of this advice does not help.


For now, I try to avoid social gatherings with a high concentration of people from my program. When they get together, the complaints take over conversation. At the department, I can spot someone (or a group) having a stress crisis from a distance, and I keep my distance.


I certainly hope that this climate does not continue into faculty life.


[Migrated from other question here. There were some useful pieces of advice, so I hope that respondents will move their points]



Answer



(as suggested by jabberwocky, I have moved the last part of my answer from here to this question)


Kvetching is a perfectly normal part of mental and social hygiene, but to what extent depends on the person. It is also a self-affirming activity: If complaining leads to positive social experiences (people you talk to relate to your experiences and opinions and share them), you will do this more often. If unchecked, this vicious circle can easily cross your tolerance threshold for complaining (which is different for each person). So, first of all you should keep in mind that "too much complaining" is your subjective view, not an objective truth (absent a concrete case of someone spending the day complaining instead of working and then failing to meet a deadline). Of course, if you'd rather have less complaining around you, it's perfectly legitimate to try to break that circle.



The best strategy (outside of avoiding complaining peers, which you apparently now follow) is often to lead by example: Do not respond to complaining with your own complaints (especially not with ones about their complaining), but try to steer the conversation to happier grounds by



  • getting them to relate positive experiences about their PhD;

  • mentioning ones you might have had (without showing off -- this one can be tricky);

  • taking an interest in their lives outside of academia.


In short, show them that they can have positive social interactions without complaining. If enough people around you feel the same way as you do, this usually works.


To your final remark: This is by no means limited to PhD students (or even academia) -- you get similar "hot spots" among early-career faculty simultaneously applying for permanent positions (in Europe) or trying to get tenure (in the US), or among tenured faculty of any seniority any time a major evaluation (of a grant or institute) or reaccreditation is imminent.


career path - Does my work in industry carry any weight in academia?


I have no academic (peer-reviewed) publications to my credit but close to 6 years of industry-based experience. I have just completed a PhD in sociology.


Does my work in industry carry any weight in academia?


My work in industry included activities such as developing codes and operational manuals in a particular field to be used by operators in that field (e.g., a health and safety manual).



Answer



Weight in academia is carried mostly by peer-reviewed research publications, published in academically reputable venues such as research journals, conferences, books with reputable publishers, reputable preprint servers, ... If you get these publications from industry research, you get academic weight. A famous example for prominent research in electrical engineering done in industry are the Bell laboratories.


Codes and operational manuals are not academic publications, and typically carry little weight. In order to get that, you have to publish academic papers about the codes and manuals, or publish papers about research results obtained with them.


Monday, 23 April 2018

molecular biology - How to identify the genes that distal enhancers pair?


I am writing a project proposal and I have to talk about this problem: how to identify the genes that distal enhancers pair?


I am really new to this topic and I don't know what it is all about. I have been searching the literature but I did not find anything useful. Can someone explain to me what it is all about? Maybe suggest some papers to me.




Google Scholar: how to exclude some countries from the search?


I use the google scholar alert system which sends me new studies made on a specific saved search. I'm looking for a way to exclude research conducted in some countries (or to only include some countries).



Answer



Try combining the - operator with the site: operator with the domain suffix for the country or countries in question. So e.g.




basketweaving -site:.fr -site:.uk



searches for basketweaving, but not in France or the UK. If site: works in Google Scholar, this should be more effective than trying the (English!) name of the country.


phd - How does the admissions process work for Ph.D. programs in the US, particularly for weak or borderline students?


When applying to a PhD program in the US, how does the admissions process work? If an applicant is weak in a particular area, is it possible to offset that by being strong in a different area?


Note that this question originated from this meta answer. Please feel free to edit the question to improve it.



Answer



Please feel free to edit the answer to improve it.


Generally, PhD programs in the US have many more applicants than they can accept. The number of positions is limited by finances (a department can only afford a limited number of RAs and TAs), space and resources (students often need offices and access to equipment), and the ability to supervise the students (there is a limit to the number of PhD students a faculty member can effectively supervise). The admissions committee must decide which of the qualified applicants are most likely to be successful researchers while taking departmental politics into consideration. These politics include things like the start-up package for Professor X including a funded PhD student and a particular resource being already at capacity.


The admissions committee bases its decision on a number of pieces of information including GPA, GRE scores, statement of purpose, references and interviews and for international students TOEFL scores. There is no formula (e.g., 6×GPA + 1×GRE + 2×references + publications) by which applicants are ranked, but some universities and/or departments set minimum requirements (e.g., GPA over 3.0 or a TOEFL over 85). The admissions committee looks at the entire application to make an informed judgement. This means that being strong in one area can, and does, offset being weak in another area.




When admissions committees consider the GPA, they are considering a number of factors including the grades: the strength of the school and major, the types of classes, and trends. An applicant who did poorly in first-year general electives will be looked at very differently from a student who did poorly in advanced specialized classes. The major is not nearly as important as the relevant classes. For example, an engineering department might look more favourably on a math major who took, and did well on, engineering and applied-math electives than an engineering major who took humanities electives. As with everything in the admissions process, the admissions committee is trying to judge the potential for research success.


Compensating for a low GPA and major/background mismatch


A low GPA can be offset by a strong research record highlighted in the SOP and letters of reference. The SOP and letters of reference can also be used to make the admissions committee aware of any extenuating circumstances that may have lead to the low GPA. Similarly, the SOP and letters of reference can be used to address how your major and background prepare you for research in the field that you are applying to. Strong GRE scores can also help offset a low GPA, and a strong GRE subject test can compensate for mismatches between majors. The best way to offset a low GPA, or a mismatch in area of specialization, is to consider enrolling in a terminal master’s degree and getting a good GPA in difficult classes.


I would like to add that an excellent way of improving a low GPA is by taking a senior thesis course, which is almost always available. Not only is this a proven way of building close ties with one or more faculty members (who will supervise you in your thesis) and getting those strong, personalized recommendations, but it could lead to a publication, or at the very least, a technical report published by the department. My senior thesis experience was life-changing: I ended up doing a Ph.D. because it made me realize that I was a better fit for doing research than I might have originally thought. In terms of grades, getting a good grade on the senior thesis course is usually not difficult (especially since you’re not evaluated on an exam performance), assuming you put in the effort.


It is also important to think honestly about why certain grades are low, and what you would do differently in graduate school. Learning from failure is a crucial skill (see, e.g., Dweck’s research on growth mindset, as well as her widely-read book). In fact, almost all academics have been rejected by some of the programs, fellowships, grants, and journals that they have applied for or submitted to, and many have even failed classes. Finding constructive ways to deal with negative feedback, rejection, and failure is crucial in academia.


Examine why you struggled or what went wrong and how you can address a problem like that in the future. How have you developed the knowledge and skills that would have helped you then? Depending on the kinds of problems you faced and the extent of their impact on your record, they may not be appropriate to mention in your SOP and through your recommenders’ letters, but the steps you take to address them might tell their own story. (E.g., perhaps you failed a class but then did research with a professor of the same subject; perhaps you had a rocky college record because you were immature or bad at planning, but you have now worked for five years in a responsible position at a lab.)



There are a number of limitations to the GRE in terms of predicting research success, but it is the only standardized metric admissions committees have access to. The weight given to the different sections of the GRE and the subject tests can vary substantially among departments.


Compensating for low GRE scores


A low GRE score can be offset by a strong research record highlighted in the SOP and letters of reference. The SOP and letters of reference can also be used to make the admissions committee aware of any extenuating circumstances that may have led to the low GRE scores. A strong GPA can also help offset low GRE scores.



A particularly effective way to offset a low GRE is to retake the GRE. In many regions of the world, the GRE General Test is offered year-round via computerized administration at a testing center, and your scores are given to you immediately upon completion. Upon receiving a lower-than-expected GRE score, you can, and should, immediately register for another GRE exam and begin preparing. Because of the short turn-around time, any preparation you did for the previous GRE should allow you to prepare much more quickly this time.


You are technically permitted to take the GRE General Test once every three weeks, or five times a year. However, repeat testings are detrimental to your schedule, morale, and finances, so it might be best to keep taking the test only until you receive a satisfactory score that you feel will represent your target school's applicant criteria, not until you receive the best score you believe is possible for you.


Once you have received the score you are satisfied with, the ETS offers a service to allow you to selectively determine which scores you provide to schools you are applying to, called ScoreSelect. This way, you can present your best cumulative score to the applications committee without being concerned about an older test, or one where extenuating circumstances made you perform worse than expected.



After test day, you can send additional score reports for a fee, and select from these options for each report you'd like to send:




  • Most Recent option — Send your scores from your most recent test administration





  • All option — Send your scores from all test administrations in the last five years




  • Any option — Send your scores from one OR as many test administrations as you like from the last five years




You will select by specific test dates, so your scores are all from the same testing session.



This applies to both general and subject GREs:




The ScoreSelect option is available for both the GRE® revised General Test and GRE® Subject Tests, and can be used by anyone with reportable scores from the last five years.



Again, I want to add that, in my experience, the GRE (particularly the General GRE) is a ‘filter’, nothing more. In many cases, even low GREs will be considered and not automatically discarded. Most top admissions panels do not accept one candidate over another simply based on GRE. I know for a fact that some colleges don’t even require candidates to submit GREs. When I was applying to CS Ph.D. programs a few years ago, for example, I noticed that MIT did not require GRE scores to be submitted.


In some fields, the Subject GRE is given significantly more weight than the General GRE, and so a low Subject Test score can be more harmful to a borderline application. Since the Subject Test is usually offered twice in the fall (September and October), it can be to your advantage to register for both sittings. This way, you can mitigate a poor showing on the September sitting by a stronger showing on the October sitting; and if the September sitting yields a satisfactory score, you can simply cancel your registration for the October sitting. This tactic can also be used for the General GRE in those regions of the world where computerized testing is not available.



Make sure you understand the conventions and expectations around statements of purpose in your field. In some fields, something fairly generic will suffice, and in others, it could be the decisive component of your application. Talk to professors in the field you trust about whether your approach to the statement of purpose is an appropriate one.


This is also the ‘fairest’ part of your application. If you’re passionate about the research you want to do, it will show up in your SOP unless you’re a poor writer (in which case, you might want to reconsider the Ph.D. until you’re a decent one; good writing/communication is essential for successful researchers). There are several proven techniques of getting a strong SOP. I'll detail some below, but be careful about your field, as these suggestions are definitely not appropriate in all cases. One approach you might take before you even start writing your SOP is to:




  1. Select your research area and actively check out the profiles of relevant professors, post-docs, and grad students (in that order) at the schools you are thinking of applying to. Check out their publications, and try to read (or at least skim) one representative publication before you start forming an opinion. The goals of this step are three-fold:




    1. It will give you a good idea of how productive a research group is, and whether a professor is even accepting (or currently has) students. This is closely tied to the funding situation of that professor.

    2. It will make you more informed about whether you really want to join that research group. What looks interesting at the high-level is not necessarily as exciting once you get into the nuts and bolts of the research.

    3. If you discover a really good fit (which is the best outcome of this exercise; trust me), you can use that in a big way in your application. In CS for example, students often post their code or demos. Download those and tinker with them. Apply them to new datasets. Have fun with what’s available. I’m sure similar things can be done in other research areas.




  2. After you have done Step 1, try to make contact with the faculty member of your choice. At the same time, also try to establish connections with the grad students. My adviser once showed me a list of potential Ph.D. candidates he was screening, and asked me if by chance I’d heard of any of them. As it turned out, I did know one, through early contact. Needless to say, she got the position. The rest of her application didn’t even really matter at that point. Note that the reason you should do this step after Step 1 is to enable you to write an ‘intelligent’ note to the person you’re contacting. It’s a good idea to not mention that you’re applying at all in your early emails. Instead, try to start a conversation around the actual research. Show that you’re interested and that you know what you’re talking about. (The ‘know what you're talking about’ part is pretty important though!) Become a familiar name in that group.





  3. Make sure to attend lots of talks by visiting faculty in your undergrad university. You don’t know where that will lead you. If someone’s talk influences you to pursue an area of research, that’s an excellent thing to reference in your SOP.




How does all this relate to the SOP? Well, essentially the SOP is your (diplomatic) chance to show your committee that you did this and more. You can drop faculty names you’ve successfully contacted, and even reference papers. You can personalize each application. Most SOPs don’t cite even a single paper. Citing a paper though will move your application up another notch in the eyes of an academic committee, but only if you do it intelligently and appropriately.


Having reviewed certain applications, I would also like to mention one major flaw that shows up in the majority of the SOPs that get rejected. The SOP is not the document where you should get too personal. Don’t waste too many words talking about how you want to be the next Albert Einstein. I’m not saying it should all be dry, but make every word as objective (and verifiable) as you can. This is generally true, but especially so for the STEM programs out there. Academics are impressed by crisp, concise writing.


Compensating for a poor SOP


Compensating for a poor SOP is very difficult. A high GPA and perfect GRE scores will do little to help an applicant who has difficulties writing about research. In some fields, past research experience is expected, while in other fields the ability to write about research intelligently may suffice in convincing the admissions committee to admit you, even if you don’t have experience doing research. Strong letters of reference can, to some extent, address a weak statement of purpose. However, there is generally a strong correlation between the strength of letters of reference and past research experience. If you have no official research experience, try and get letters of recommendation from professors where you completed a class research project that got a good grade. Even if you didn’t do supervised research with the professor, the professor may be able to comment on your research skills and successes. Definitely contact the professor and remind them of your class project, and the grade you received. Summarize it, and attach the project to the professor so they can refer to it.



You’ll want at least one very strong reference for a top-ten program, and in many cases two strong letters (three is actually quite a stretch). See my note above for how you can secure at least one very strong letter by doing a senior thesis. Try also to aim for at least one research internship during your undergrad. This could lead to a second strong letter from a researcher in your area. Letters from industry don’t usually have the same appeal for academics.




Improve your English and take the TOEFL again; generally schools have minimum TOEFL scores, and taking a student whose English isn’t good enough can be a huge headache. Some schools in the US will do phone/Skype interviews with prospective foreign students to get a sense of their English.



Every university/department handles the stated minimum requirements differently. Sometimes a hard threshold is used such that if an application fails to meet all the minimum requirements, it will not be considered at all. Other times, the threshold is soft, and applications that do not meet all (or some) of the minimum requirements will still be considered. If you do not meet the minimum, only the department you are applying to can tell you if you are eligible to apply.


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