Q&A

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  • Johan Prins added an answer in Quantum Physics:
    Was Niels Bohr suffering from insanity?

    I have just looked up quotes from Niels Bohr. Many of them are so absurd that it is questionable that they could have come from a sane mind. For example: "If anybody says he can think about quantum physics without getting giddy, that only shows he has not understood the first thing about them."

    So what Bohr is arguing here is that when a person approaches him and claims that he does understand and can explain quantum physics, Bohr would argue that it is impossible since only a person who does not understand quantum physics, is able to understand quantum physics! Is this not the type of argument one only expects within a looney bin?

    Johan Prins · Sage Wise 66 (Pty) Ltd

    Dear Igor,

    How can you state tat "Bohr understood" when Bohr himself claimed that he is not able to understand at all, and that all persons who are able to understand must be treated as crackpots, since it is impossible for anyone to understand? I find this reasoning absurd and a sign of insanity! Do you think that a sane person wil claim: "You are not reasoning, you are only being logical"? How can a sane person reason without logic?

  • How can I calculate the free energy of a crystal, like BeO in gaussian?

    How can I calculate the free energy of a crystal, like BeO in gaussian?

    Prashant Uday Manohar · Birla Institute of Technology and Science Pilani

    The thermodynamic quantities like Gibbs' energy, Entropy, Enthalpy, etc are calculated using their statistical thermodynamical formulae and require computation of translational, rotational and vibrational partition functions. Generally, any quantum chemistry software capable of running geometry optimization (for local minimum) followed by vibrational frequency computation will compute these quantities at the end of the frequency job. For more accurate results, consider anharmonic correction if your software allows and is affordable for your system. It is very important that frequency must be computed at the same level of theory and basis set that have been used for geometry optimization.

  • David Sundin added an answer in Nanoparticles:
    In WEDM, is it possible to use nanoparticles in the dielectic fluid?

    See above

    David Sundin · Ambit Technical Consulting

    Nanoparticles have been shown to increase thermal conductivity of a dielectric fluid, as Mr. Sharma notes.  They have also been used to enhance electrohydrodynamic characteristics of fluids.  Care must be taken that the particles themselves are nonpolar and that they are of correct size and low concentration as  to not influence the dielectric strength of the fluid mixture.  

  • Is any sort of correction needed for the P values obtained by multiple linear regression

    In my current work, we have calculated the p value for association using multiple linear regression in SPSS for 6 SNPs (three different models -additive, dominant, recessive) with several quantitative traits eg: axial length. There is no option for correction (post hoc as in ANOVA) available in SPSS linear regression window. So

    i) Is correction for the p values obtained from this is absolutely necessary,

    ii) Is there an option in SPSS that i have missed,

    iii) can a manual bonferroni correction (0.05/ the no of SNPs) be sufficient/ appropriate

    Kindly help out with the same.

    Thanks in advance

    Frederico Rosario · University of Lisbon

    Hi Ferdinamarie.

    In general, there is no need to adjust p-values in MLR as they are already ajusted for the presence of all the variables in the model. Of course you need to check the assumptions of the linear model (errors with normal distribution, homocedasticity, inexistence of multicollinearity, inexistence of serial correlations among the errors...) as this can influence the estimations of your model.

    I hope this will help you!

    Best

    Frederico Rosário

  • Kindly suggest some recent area in the field of wireless communication for phd requirements

    kindly suggest some recent area in the field of wireless communication for phd requirements

    Salman Arain · Frederick University, Nicosia Cyprus

    Wireless Sensor Networks is the hit topic now a days, apart from that spectrum sensing, cognitive radio networks , Aggregation in LTE networks

  • Graeme Smith added an answer in Human Genetics:
    If we oppose human genetic engineering, does that mean we're anti-science and anti-progress?

    If we oppose human genetic engineering, does that mean we're anti-science and anti-progress?

    Artur, I didn't say that conservationism is religious, I said that ethics often has a belief component related to religion, which is a completely different thing. There are many reasons for ethics, religion is just one of them.

  • Ana-Maria Ciobotaru added an answer in Floods:
    Some countries in East Europe: Serbia and Bosnia, are experiencing destructive floods. What systems would be needed to prevent sudden severe floods?
    When I browsed, I find a few links:
    https://www.gov.mb.ca/conservation/waterstewardship/iwmp/index.html
    http://usfloodcontrol.com/
    Is your expertise in this area? What systems would be needed to prevent sudden severe floods, in places that do not normally experience this phenomenon? Can you provide some helpful suggestions, so that water is a useful commodity, rather than a 'foe'?
    Ana-Maria Ciobotaru · University of Bucharest

    ESTOFEX - probability of one or more extrem weather  In Europe !

  • Louis Brassard added an answer in Societies:
    What's the difference between that die a martyr or die naturally in your concept?

    In some societies, beliefs die a martyr is better than that and you die on the bed. There are examples of the reality of war and the defense of honor, what do you say about this concept?

    A martyr in mythologies, in fictions, in sacred books, in history , is a heroe, a person taking action of behalf of others in need, or in defense of integrity or a moral cause, that voluntary accept death for its cause. They are: Socrates, Jesus, Tarek al-Tayeb Mohamed Bouazizi , the patriots of all the social revolutions. Some heroes such as Siddhartha Gautama died peacefull as they live, and they are not martyr.

  • Educational Models

    This paper outlines the development of a cognitive computational model and an initial experiment using the model. The link will take you to the full text. Please take a look and let me know if you have any questions.

    Richard L. Lamb · Washington State University

    Sorry got cut off I was curious (from a philosophical view) if there was perceived value in the use of computational models in eductionsl research. 

  • Ronis Maximidis added an answer in HFSS:
    Which software is better for antenna designing specially micro strip patch antenna? HFSS or I3d or CST

    Whose results are really precise to the actual measured result.

    Ronis Maximidis · Democritus University of Thrace

    For planar antenna design the IE3D is prefered. It is based on MoM method and gives more accurate results.

  • Approaches to teaching analytical/critical writing to psychology undergrads?

    What are some resources others have found helpful? For context, I am teaching an undergraduate course called Culture, Ethnicity, and Mental Health at a university in New York City. Critical/analytical writing skills are not the primary focus of the course, but nevertheless very important skills for students to develop. I am interested in accessible, incremental approaches that will help my students learn these skills. Any and all ideas are welcome! 

    William Somerville · New School University

    Very helpful Christian, thank you!

  • David Sundin added an answer in Chemical Ionization:
    Is it true that low pH means high degree of ionization or high solubility?
    I think low pH means high degree of ionization. However frankly speaking, I want to know about the relationship between "degree of ionization" and "solubility".
    There are two types of chemicals such as SnSO4, NiSO4. I dissolve two chemicals in water at same molar concentration(0.01 M). Then I could get data about the pH of two types of solutions. What I could see is that NiSO4 looks more soluble in water (SnSO4 doesn't look soluble in water perfectly), but the pH of NiSO4 solution (pH5) is much higher than SnSO4 solution(pH2.5).
    Therefore I could conclude that the relationship between the degree of ionization and solubility is not valid. I couldn't accept and understand this result.
    Can anybody explain the relationship between those?
    David Sundin · Ambit Technical Consulting

    As Fadhil states, you cannot make a direct correlation between degree of ionization of a material and its solubility.  Organic fluids can be non-polar, yet excellent solvents.  Ionization occurs best in aqueous solutions, yet they are only solvents for other hydrophilic materials.  Best of luck...

  • Rubén Barone added an answer in Chiroptera (Bats):
    Does someone know information (papers) about experiences with bat management and their monitoring in cities?
    I'm working with conflict between human and bats in a chilean city, I need to know another experiences around the world, with bats, e.g. Tadarida brasiliensis

    Hi. You can contact with Dr. Matti Masing, from Estonia, who has published a poster or a conference paper on this subject, relating to the bat fauna of several European cities. 

  • Rocco Piazza added an answer in Transfection:
    Why did I achieve successful transfection, reporter gene expression but no GOI expression?

    I successfully transfected murine melanoma cells with a lentiviral plasmid 5´LTR-CMV-GOI-SV40-ReportergeneRFP/Selectionmarker-3´LTR.
    GOI - coding region of my GOI has 350bp and an n-terminal signal sequence and should be secreted.

    I selected the reporter gene expressing cells by FACS, checked the insertion of the plasmid by PCR (fwd primer binds CMV promotor region and reverse primer binds SV40 region) and verified the PCR product by sequencing. All this worked out fine. When I wanted to check the expression level of my GOI compared to gapdh and to the non transfected cells, the expression levels of my GOI shows up >10 CTs later compared to gapdh, same levels as my untransfected cells. So I am only detecting the "endogenous" mRNA and not the mRNA of my inserted gene.

    So either I have a detection problem of the mRNA (I tried different Primer pairs for sybr green - since I could not detect the mRNA with my own designed primers I even checked with Taqman primers - fail!, also reverse transcription with random primers and oligodTs shows no difference) or there is no mRNA transcribed or immediately degraded...
    Technical support from ABMgoods (company from where I purchased this vector) explained that the polyA signal is at the end of 3´LTR which also means two different mRNAs are made: one starting from CMV until 3´LTR and the second starting at SV40 until 3´LTR. Since my cells are expressing the reported gene (verified by FACS and fluorescence microscopy) there should not be a problem with the polyA signal...

    Maybe you have any suggestions - why I cannot detect the mRNA of my transgene?!

    Thanks a lot

    Agnes

    Rocco Piazza · Università degli Studi di Milano-Bicocca

    Hi Agnes,

    you sorted your cells by FACS, so I assume it's no longer the whole population, but only the subset with the highest expression. BTW: what's the efficiency of your infection? Is it possible for you to test the effect of the chemokine on your cells? Could it be that your GOI, even if not toxic, slows down cell growth, induces differentiation or similar ?

  • Which are the best practices in decision making when unexpected events happen that affect the normal business continuity?

    I am interested in knowing what are the best practices in the industry when an unexpected event happens that affect the business continuity.

    Upananda Witta Arachchilage · Wayamba University of Sri lanka

    Dear Alix,

    According to empirical evidence, heuristics may be the best practice.

    Upananda

  • Khaled Said Ali asked a question in Camels:
    Does anyone know method for determination of milk content?

    I would like to characterize milk content of camel and cow, especially the proteins and lipids by easy techniques.   

  • Irina Nakashidze asked a question in Base Pairing:
    What is the best fragment size for detection of polymorphism?

    The best results are achieved using  fragments around 150 base  pairs in length.

  • Amer Draa asked a question in Differential Evolution:
    About local search

    Hello everyone;

    I want to add a local search operator to a variant of differential evolution I am working on. The problem I found is that there are many local search approaches. Could any one advise me about any specific LS method?

    Thank you in advance

  • Is quantum vacuum propulsion a viable research area?

    There is now an official NASA report of experimental results from Sonny White's team at JSC: http://ntrs.nasa.gov/search.jsp?R=20140006052 .  There are many news media reports (some of which incorrectly picture Sonny's Albucurrie drive instead of the vacuum drive http://www.nbcnews.com/science/weird-science/impossible-space-engine-might-work-nasa-test-suggests-n171201 ... a better photo is available here http://sploid.gizmodo.com/nasa-reveals-new-impossible-engine-can-change-space-t-1614549987).

    On the face of it, this technique seems to violate conservation of momentum.  As far as I know, no one has provided a theoretical model of how this might come about without tearing up almost all of physics.  Do the researchers need to look harder for other explanations of their results?  Is this time different than other far out reports such as cold fusion (20th century) and perpetual motion (19th century and earlier)?  Or should theoreticians take these results as a prompting to look at ideas for how the momentum might be carried away, such as a vacuum ether perhaps, with momentum being absorbed by the vacuum ether generating masses?

    Robert Shuler · NASA

    Paul, just a few days ago I talked with an R&D engineer here who has consulted with White, and he brought up the same concern, about the leakiness of the setup, and a possible small force from stray RF.  I believe what White requested from our division is help with a better setup, less leakiness, more repeatabiity.  So they seem to be doing the right things, just maybe bragging about results a bit early.  It is a temptation I fell into again this week, sending out a paper and then realizing all the mistakes in it.  When we get our friends to look over our work they are unwilling or too busy to be critical.  :D

  • Is there a general measure that indicates the uncertainty and/or Information asymmetry of an industry? Is there a close proxy measure?

    Is there a general measure that indicates the uncertainty and/or Information asymmetry of an industry? Is there a close proxy measure?

    Upananda Witta Arachchilage · Wayamba University of Sri lanka

    I agree with Stanisław, Uncertainty does not coined with asymmetry of information but with transaction cost  (North, 1990). Industry, generally attempt to reduce risk since probabilities of outcomes are known.  Uncertainty, arise as a result of not knowing the probabilities of outcome.

    Friction of Transaction cost and information asymmetry may indicates by the quantity of entrepreneurial activities and the number of entrepreneurs engaged in the  industry. 

    Upananda

  • Sangita Das added an answer in Plant Genetics:
    Which is most important trait in heat tolerance studies in crops: Spikelet fertility or plant yield in crops?

    Some varieties in rice showing high spikelet fertility under heat stress, but yield per plant is much less. Other varietes showing much less spikelet fertility but when we see yield per plant, it is more than that of high spikelet fertility varieties under heat. Which one is important to classify a variety as heat tolerant?

    Sangita Das · Assam Agricultural University
  • Mohamed Ismail added an answer in ChIP-Sequencing:
    How can I get good quality DNA for Chip-seq?
    I am trying to isolate and purify the DNA for Next Gen Sequencing after doing Chromato-immunoprecipitation (ChIP). I have tried doing purification using Qiagen based columns (high loss of DNA) and also Chelex reagent (DNA purity less) and I am still getting 260/230 ratios to be very low (0.5-1). As the concentration is low for Chip DNA I am using nanodrop for measuring the concentration and not a spectrophotometer but I do plan to cross check with Qubit. Any suggestions on how to go about getting good quality DNA for sequencing?
    Mohamed Ismail · Harvard Medical School, Massachusetts Eye and Ear Infirmary

    I agree with Tonis statement. Mostly, the Nanodrop shows poor quality of chip DNA and undetectable levels  in specific and sensitive Qubit systems. In our experience, these samples on  PCR analysis shows sufficient enriched DNA. However, I'm sceptical to take this further for library construction. I would consider pooling of Chip DNA prepared with good number of cells before the purification steps to improve the DNA yield. Make sure the final immunoprecipitation buffer contains no more than 0.1% SDS.  I find iDEAL chip protocol supplement buffers to perform chip with high volume cell lysates. This could also help in working with low abundant proteins.

  • Max Stanley Chartrand added an answer in Medicine:
    Does the responsibility of researchers end with the scientific publication of their findings?
    Or should he or she also ensure that these findings find a way to a) non-scientific public and b) the implementing authorities / institutions (a practical reference provided)? I have made it my habit to any scientific contribution to compose another layman's contribution and to publish in order to create the possibility of practical implementation. All non-academic partners are extremely grateful for it. Without access to databases they would probably know nothing about these results and findings. Other ways to make research applicable?
    Max Stanley Chartrand · Northcentral University

    True, Nicolas, but about 90-95% of drug research is financed privately. Litigation from the market is a huge chunk of the US healthcare cost, growing by leaps and bounds as more and more symptomatic, narrow-market comes out. LIkewise, the average physician in the US pays out of pocket $100,000-300,000 per year for liability insurance to protect them from lawsuits. That is also a sizable chunk of the US healthcare system, which brings us to defensive medicine that is so rampant it is not unusual to spend $30,000 just to diagnose a chronic headache. The fact that someone else is paying for it drives this madhouse scene over the cliff as healthcare costs have inched their way to more than 20% of our gross domestic product (GDP) and promises to gobble up 24.6% by the year 2017 when the ACA is fully impelemented including its 27 new taxes and penalties. When up to 80% of all prescription drugs in the world are consumed (and paid for by the tax payer) by only 4% of the world's population, one might can fathom the depths politician/private corporation collusions have brought us to. And it started with what was considered to be "objective research" bolstered by the most elaborate and well financed marketing and sales program in history.   

  • What is the key factor to prevent HepatoCelluar Carcinoma in the Mongolia ?

    HepatoCellar Carcinoma is the most prevalent malignancy in Mongolia. Although vaccination programs for hepatitis B virus has been implemented, the prevalence of chronic hepatitis B and C is still over 10%.There has been no study of the genetic traits of Mongolians as a causative factor for HCC. What is the key to prevent the HCC in Mongolia ?

    Julian Schulze zur Wiesch · University Medical Center Hamburg - Eppendorf

    In addition to the points added by Dr. Gish and Dr. Fung it will be crucial to reduce dietary exposure to aflatoxins in order to reducethe HCC rate in Mongolia

  • What are the modulators for symbolic and embodied language processing?

    Language processing is probably neither wholly symbolic (cf. Tulving, 1984) nor wholly embodied (cf. Barsalou, 1999). Rather, on recent proposals, both cognitive systems would play a role (cf. Louwerse 2007; Mahon & Caramazza 2008).

    In regard to possible modulators behind each system, evidence has suggested a dependence on task and stimuli, as far as I know. Now, on a further step, I intend to find out just when either symbol system will 'kick in.' 

    I would appreciate any suggestions of relevant literature, as well as your own ideas. 

    Thanks in advance,

    Pablo

    _____________________

    • Barsalou, L. W. (1999). Perceptual symbol systems. Behavioral and Brain Sciences 22. 577–660.
    • Louwerse, M. M. (2007). Symbolic or embodied representations: A case for symbol interdependency. In Landauer, McNamara, Dennis & Kintsch (eds.). Handbook of latent semantic analysis 107–120. Mahwah, NJ: Erlbaum.
    • Mahon, B. Z., & Caramazza, A. (2008). A critical look at the embodied cognition hypothesis and a new proposal for grounding conceptual content. Journal of Physiology - Paris 102. 59–70.
    • Tulving, E. (1984). Precis of Elements of Episodic Memory. Behavioural and Brain Sciences 7 (2): 223–68.
    Pablo C De Juan Bernabéu · Tilburg University

    Excellent. Thanks!

  • Giulia Ranzini added an answer in Reasoning:
    Do you think some senior researchers are really busy or they pose to be busy?

    Many of you may have experienced that some senior researchers usually don’t take part in Q&A and therefore don’t share their knowledge and experience which is essential for students and junior researchers to rise in their professions. What can be the possible reasons? Please share your opinion or/and experience.

    Giulia Ranzini · University of St.Gallen

    It's hard to generalize, but what I think is sometimes hard to grasp as a graduate student (if I think of myself, for example), is the amount of responsibility and - let's say - collateral activities that come with higher positions, e.g. looking for funding, bureaucracy, more teaching, more grading, plus all the keynoting/representation which are fun but usually also pretty straining.

    Then of course the tendency to sell oneself as Unbereably Busy And Overloaded With Work exists in academia just like in other professions. Peer pressure exists, and I don't think we can deny it. Yet, I do think workload grows with experience, and with responsibilities.

  • Can formal institutions replace informal institutions without adverse effects on economic growth?

    Institutional economics is gaining attention from researchers to explain why some economies attain higher economic growth while others not. Reasons for not attaining economic growth have been (according to Estrin et al.,(2006)) institutional framework.

    Upananda Witta Arachchilage · Wayamba University of Sri lanka

    Thanks Winton for example.

      I argue that  those examples are not outcomes of  economic freedom but governing mechanisms which are free and fair..  As a result, people tend to produce and compete fairly.  When the friction of transaction cost and asymmetry of information is lowered ( through a governing mechanism), economic growth is inevitable.

    Upananda

  • Healthcare Providers - Who is utilizing Geriatric Assessment Tools for Hem/OncPatients? When did you start? Who conducts the actual assessments?

    I am currently considering a Lean Sigma Project for the implementation of new geriatric care principles including an Assessment Tool.  I am interested in information related to other facilities who have implemented such a program.  I am curious if anyone has been able to analyze health outcomes related to implementation of a Geriatric Assessment Tool?  or if anyone has been able to document an economic impact ....I would like to determine which allied health professionals are conducting these assessments and if mid-level practitioners are able to bill for this "Provider Service" 

    R. Michelle Baker · Cancer Treatment Centers of America

    Thank you Brain...I will look into the information that you have referenced above.