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  • Lawrence Margulies added an answer in Rietveld Refinement:
    How to enter new crystal structure to Rietveld Refinement in Xpert High Score Plus?

    I try to enter new crystal structure from online available database for BaCO3 - barium carbonate, but Xpert High Score Plus shows one error as in the figure below.

    I already tried to change database or even enter it manually, but nothing works.

    Does anyone have any idea how to solve it?

    Lawrence Margulies · University of Guelph

    Use a program that is not a black box.

  • Jonghyuk Yoon added an answer in Thin Layers:
    Why do I get holes in graphene like carbonaceous film deposited through CVD on copper?

    I am trying to deposit graphene from a custom-designed CVD setup using camphor as carbon precursor but as of now proper nm thin layer has nt yet been there on the copper substrate and the film has small holes over entire coverage.

    Jonghyuk Yoon · Samsung Techwin Co.

    There are several cases that you can see the holes as follows;

    When the copper foil was annealing around 900~1000℃, some gases which copper originally contains oxygen, or other sulfer  may come out to the surface. So it become the surface impurites.  Also even when you pre-annealed cu foil in inert or hydrogen atmospher, the hole cannot be fully removed. The holes are caused by lots of experiment factors, such as Cu purity, pre-annealing condition, surface roughness, and CVD chamber cleaness, etc.  One more,  If you transfer the graphene to other substrate such as si wafer, you can get easily extra holes because of non-perfect transfer. Thus, you'd better observe the surface of Cu foil right after graphene synthesis process.  Honestly, I am also looking for the solution to perfectly remove the holes.^^  

  • Lawrence Margulies added an answer in Diffraction Data:
    How might I make a quantitative analysis of the crystal shape by XRD?

    I want to compute shapes of crystals from X-ray Diffraction data, thank you.

    Lawrence Margulies · University of Guelph

    still laughing

  • Julie Fisher added an answer in NGOs:
    Did you analyse relation between contemporary university and NGOs?

    Clark's triangle of coordination (1983) seems to the model of relations: university - state - market. What is the place in these relations for NGO and social society in general?

    Julie Fisher · Kettering Foundation

    In my recent book, that chapters on South Africa have a discussion NGOs that are housed at universities, particularly law schools. These democratization NGOs most often work on human rights.  I did not find that this pattern was common in the two other countries I studied- Argentina and Tajikistan. See www.importingdemocracy.org

  • Donald Schlomer added an answer in Systems Thinking:
    Can anyone help me to look for literature on supporting a systems thinking approach in innovation management?

    In particular, I am interested in papers about Innovation Management providing dynamic models and systemic approaches balancing the need for new ideas (being creative) and making business (scaling)

    Donald Schlomer · Walden University

    I am sure you found The Fifth Discipline by Senge (2006) and Project for Portfolio Planning cycle: Project-based management for the multiproject challenge by Platje, Seidel, and Wadman (1994).

  • Cameron. J. Shearer added an answer in Tuna:
    What are the proper substrates to use for Peak-force TUNA and Conductive AFM?

    For running Peak-force TUNA and C-AFM, we need a substrate which is conductive enough to pass the current to the sample; however, it should not be too conductive to saturate the current. What do you suggest as a proper substrate?

    Thank you so much for your help in advance. 

    Cameron. J. Shearer · Flinders University

    I have also used Au Si wafer (2nm Cr sticking layer, 50 nm Au - deposited via sputter coating). Just make sure you use a conductive tape to electrically connect the gold to the base.

    Alternatively, HOPG can be used if you need a flatter substrate. 

    I have rarely had an issue with the substrate being too conductive. You can always just use a lower potential for current mapping.

  • Dahlia Karto added an answer in Coloring Agents:
    Should I use Food Coloring to test water uptake by plants?

    Hello, Im looking for safe dye/coloring agent to test water uptake by roots. Should I try food coloring? Is it harmful for the root tissue? I was looking for nitrogen free coloring agent, but not sure if one like that exist...


    Dahlia Karto · State University of Malang
    1. ya you can used safranin
    2. methylen blue
    3. and other the bright colour
  • Jill Miotke added an answer in Zebrafish:
    Is possible to follow Zebrafish develop in diluted E3 medium?

    I'm trying to see the development of Zebrafish embryos (4hpf-96hpf) in dilutions of E3 medium in deionized water: 2%, 4%, 6%, 8% and 10% of E3.

    I put the 5 embryos in well in a 24 well plate and do static system (did not change the medium during all the time).

    All the embryos in the dilutions have normal development until 72hpf after this time they have malformations, pericardial edema, slow heartbeat and they died in 96hpf.

    I do some wells as control with 100% E3 medium and the embryos were fine in these wells.

    I really do not understand what is happening. If someone can help me with anything about this I would be very grateful!

    Jill Miotke · University of California, Irvine

    Hi Carolina,

    All I can tell you is what our dishes measure.  For a standard 100 cm diameter dish which is 2 cm deep (total), we try to fill it about 1/2 full.  We don't measure out the amount, we just pour in the embryo media.  So I would guess that about 80mm to 1 cm of depth should be fine.

    Good Luck!


  • Cameron. J. Shearer added an answer in Water-Soluble:
    Is there a commercially available, water-soluble polymer that will re-form the solid by simple evaporation of the water from it?

    I'm wanting to make a thin film on a surface by evaporation of the water from a water-polymer solution.  Is there a commercially available polymer that will dissolve in water, but come back out of it when the water is allowed to evaporate?

    Cameron. J. Shearer · Flinders University

    Most polymers with a charged head group will dissolve in water. Provided they have a large molecular weight, they will remain on your surface after evaporation. Maybe polyethylenimine is an option, (http://en.wikipedia.org/wiki/Polyethylenimine), you can buy from most chemical suppliers and often comes already dissolved in water. 

  • Rafael Trevisan added an answer in GPx:
    How to calculate an oxidative stress index?

    How to calculate an oxidative stress index based on data of antioxidant enzymes (SOD, CAT, GST, GPx ...) and oxidative damage (LPO...)?

    Rafael Trevisan · Federal University of Santa Catarina

    There are people that use the redox potential of the pair GSSG/GSH (using the Nernst equation) as an idea of the cellular oxidative stress, or how reductive/oxidative the cellular environment is. It is a general overview, as oxidative stress can be different in at subcellular compartments, or even at different time points.

    But I am not sure if you can calculate or measure oxidative stress, especially based on enzymatic assays... ROS levels, antioxidant capacity and cellular damage can help you to define if you have a light/moderate/severe oxidative stress condition, but it is not an index.
    And eventhough, many assays that we currently use can be quite inconclusive, as discussed on the link below. Therefore, I would suggest to be careful about defining or estimating oxidative stress based on enzymes and LPO, it can  be quite tricky.

  • Paul Rutland added an answer in Hex:
    How can i make HEX labelled primer to work?

    I optimized and got desired band with unlabeled primer set. But when i use labeled primer with HEX (Left primer labeled) i'm not able to get the band.

    Three other labeled (other labels) primers worked fine with previously optimized conditions with unlabeled primer,

    Paul Rutland · University College London

    i never found that the dyes fam, tet or hex made any difference to getting a pcr band although in the analysis hex did give a weaker signal so a better product or lower dilution was needed to get the same signal strength. I would check very carefully that the sequence of the old unlabelled and the new labelled primers are identical, Also most pcr primers are just desalted so can be stored  under many conditions but dye labelled primers are usually highly purified so need to be reconstituted in alkaline TE not water as water is acidic and can depurinate single stranded dna very easily. Is the template dna the same...it would be unfortunate to find that there is a polymorphism near the 3' end of one of the primers in your samples. try dropping your ennealing temperature  ( a gradient would be ideal if your cycler allows it ) and double the amount of primer and include a control with the old primers added to check that the pcr is working

  • Anthony Clemons added an answer in Networked Control Systems:
    What are the best recurrent neural network training methods on-line ?

    The use of the recurrent neural networks in control systems becomes more and more interesting subject, but that is based on the training method that we use , in control we need our training to be on-line and this is convenient for the applications that we are trying to work on , so what are the learning approaches in the dynamic neural nets " recurrent " and which ones are the best among them ? 

    Anthony Clemons · Columbia University

    I'm not going to answer your question with an academic premise, but rather an example that utilizes the best congitive methods in education. The Minerva Project is a blended program whereby students take courses online and in residence. The technology used is state of the art and considered to be the Ivy League of online learning. Check it out here and read about the organization's learning philosophy https://www.minerva.kgi.edu/.

  • Janet Hunt added an answer in Labor Economics:
    Has anyone got access to the microdata from the Household Budget Survey 2011-12 of Tanzania?

    The publicly-available data on the Tanzanian statistical agency's website has information regarding household characteristics. But, there is no person-level data, i,e., detailed information about the individuals in the household such as their age, employment status etc. In contrast microdata from the earlier HBS (2007) contain person-level data.

    I would appreciate any leads on how to obtain the person-level data from 2011-12 HBS.

    Thank you!

    Janet Hunt · Australian National University

    This is the problem with household surveys - we have developed a new measure called the Individual Deprivation Measure which would answer such questions in the future. Check it out on the website of International Women's Development Agency - the IDM information is all linked to that site. Won't solve your immediate problem I realise but thought you'd like to know about the IDM.

  • Adam B Shapiro added an answer in Receptor Pharmacology:
    What chemicals can be used to intenalize receptor present on cell surface ?

    any  chemical or substance which can cause internalize the receptor present on the cell surface which lead to receptor degradation in the cell

    Adam B Shapiro · Entasis Therapeutics

    Depending on the receptor, internalization may occur subsequent to binding its natural ligand, or crosslinking by antibodies.

  • Azzam K Almosallami added an answer in Special Relativity:
    Is relative simultaneity a misinterpretation of Special Relativity?

    I really need a lot of feedback on this particular issue.

    I think that relative simultaneity is a computational effect of no consequences to real temporal relations. This is based on my analysis of simultaneous trajectories.

    My claim of apparent nature of relative simultaneity is based on the assertion that relative lengths of rigid objects or points moving at a constant relative distance to each other in a stationary system are not conserved (in general ) in the moving system after Lorentz transformation when expressing multiple points trajectories in terms of common time of the moving system.

    More details in the linked document and relevant draft article available from my RG profile

    Azzam K Almosallami

    Dear Eric, and Dear All,

    Thank you very much Eric for your  analysis of  the thought experiment (London-Paris). I really interested with your discussion.

    As you said at the end; 

    The apparent “paradox” of “time dilation” comes from neglecting the above
    distinctions and naively assuming that t and t′ in the Lorentz equations are
    “simultaneous” comparisons of two clocks. They are not. That leads to the nonsense that t = γt′ and t = γt′. (I call this “Dingles mistake”). Of course, tp and tL don’t mean the same thing, and tp′ and tL′ don’t mean the same thing. The quantities tp and tL′ are illusory “dilated” times witnessed when a moving clock is observed. tp′ and tL are“proper” times.

    From the beginning of  the discussion I informed you  t and t' is impossible to be simultaneous in the Lorentz transformation and that means t not equal to t'  when the two observers see the plane on Paris. If t=t' then it is Galilean transformation and now you reach to same point.


    As you said;

    The plane is now in flight over Paris and its clock reads t1′. It then stops. (An alarming rate of deceleration! But I maintain that this does not affect the time on its clock − nothing in STR says that acceleration affects clocks!). So now we have two clocks, stationary in Paris, showing different times. I hope we are in agreement so far.

    This is a big a problem in SRT, because in this case we do not know when the plane stopped in Paris and v becomes zero,  where was the pilot seeing his plane before stopping, was it on Paris really or it was at the middle distance between Paris and London because of time dilation and length contraction if the velocity of the plane was 0.87c, and then suddenly he found himself on Paris (This is exactly the spooky action and event happened on the past which proposed by Einstein). And how the pilot was seeing the clock on the ground moving on similar rate of his clock or slower rate. If it moves in a similar rate of his clock during the motion, then that means a lot according to physics, and then it interprets the virtual particles.

     If the distance between London and Paris moving -v, then the observer on the plane must see the clock on the ground moves in a similar rate of his clock on the plane if you consider my interpretation of simultaneity, and in this case it is not required the reciprocity principle and all the paradoxes will disappear. This illustrates to you why the invariance of the energy-momentum four-vector is associated with the fact that the rest mass of a particle is invariant under coordinate transformations.  

    In this case we can understand also if y'=y and z'=z as proposed by Einstein without any prove as Dingle said or it is y'=Ry and z'=Rz. which lead to the wave-particle duality and Heisenberg uncertainty principle. In this case Sagnac effect and Hafele Keating experiment interpreted completely.

    Now when the plane decelerates how it decelerates, according to classical acceleration or according to quantum theory by exchanging radiation according to the wave-particle duality. 

    If we consider the concept of acceleration or deceleration in classical motion or relativistic motion it  is changing velocity which means gaining or loosing energy of hf, where h is Planck's constant and f is frequency which that is quantized. So, what is the concept of acceleration or deceleration according to quantum theory? And then if energy is quantized, how the accelerated particle in a uniform acceleration will moved in a continuous path 1/2at^2? Now we understand from where continuity comes from,....from objectivity, that both two observers on the ground and on the plane must agree that the plane arrives at any point in space between London and Paris. This will allow us to understand if the equivalence principle of Einstein in GR is right or wrong. According continuity it must graviton of spin 2 mediates gravitation I agree with you, and that if the two observers agree at the location of the plane at any point in space between London and Paris.

    Dear Eric,

    At the end I would like to say, there is no difference between how I interpret the simultaneity in SRT, and how you interpret it. The only difference between my interpretation and your interpretation is you proposed as Einstein proposed when the plane arrived Paris then it arrives Paris for both of the two observers. 

    I just reinterpreting the time dilation and length contraction by removing objectivity and then creating two pictures for the plane  location for the two observers each one according to his proper time as in Copenhagen school and I found all the problems in physics solved. That's clear in my paper.

    Thank you very much for all

  • Carlo Carandang added an answer in Anxiety Disorders:
    Chronic stress leads to anxiety or depression?

    Chronic stress can lead to anxiety in some people, while it can lead to depression in others. Some people with chronic stress may experience both anxiety and depression. It seems not clear how stress, anxiety, and depression contribute to each other. How can we interpret these different combinations of co-morbidity?

    Carlo Carandang · Dr. Carlo G. Carandang Inc.

    Thanks, Ilaria and Renzo. Anxiety and depression- different sides of the same coin.

  • Gabriela Echevarría added an answer in PERMANOVA:
    Is it recommendable to use a three way PERMANOVA analysis for an unbalanced design?

    I have a data set that consist of observations in four ponds and one stream. I have three factors: locality (each lake and the stream), habitat (permanent pond, temporal pond, stream) and hydrological phase (four phases). Can I analyse the data with PERMANOVA including the three factors simultaneously, even though there is only one replication for the stream? 

    Thank you for your comments. 

    Gabriela Echevarría · Venezuelan Institute for Scientific Research

    Thank you Vinicius, I agree with your suggestion. 

    Kind regards.

  • Adam B Shapiro added an answer in SNA:
    I want to run SNA conjugated to FITC with and without a reducing agent to see if I can observe breakdown products on a gel. What is the best way?

    I don't have a FITC antibody so I was considering using GelCode Blue Stain on a gel after SDS-PAGE with and without a reducing agent. 

    Adam B Shapiro · Entasis Therapeutics

    If you intend to measure the fluorescence of the protein in the gel, do it before staining with Coomassie Blue because the stain will prevent you from observing the fluorescence. Also, the fluorescence of FITC will be lost if the pH is below neutral, so scan the gel for fluorescence before fixing it in methanol/acetic acid.

  • Carl Alexander Sorensen added an answer in Family Therapy:
    Can anyone suggest to me a good example of family assessment models?

    I am trying to prepare a "family assessment model" proposal as  an assignment in a family therapy course. I would appreciate references to relevant articles, files, websites or sample files.

    Carl Alexander Sorensen · University of South Carolina

    If you like SDT, there are quite a few measures available at this website:


    There is at least one family-environment-related questionnaire there (child-perceived parental autonomy support)

  • Casey Fiesler added an answer in Websites:
    How should I cite a picture/diagram from an Internet website ?

    How should I use ( I mean the guidelines ) and how should I cite ( I mean how to write the source) a picture or diagram from any website without violating the copy rights? Thank you.

    Casey Fiesler · Georgia Institute of Technology

    Coming in to this late, but I wanted to make a note here in case anyone comes across this question in the future. Citation/attribution is actually not relevant to whether use of a picture/diagram in the paper itself is copyright infringement. Using it MAY fall under fair use (or other applicable copyright exception), but attributing it properly does not impact that. Though of course, attributing a source properly is good ethical practice either way, and would ensure that it was not mistaken for plagiarism.

  • Jeanetta Mastron added an answer in Vasopressin:
    How can the "equivalent-dose" of vasoactive drugs be compared(norepinephrine, dopamine, etc) and "equivalent-volume" of crystaloid vs colloid fluids?

    I want to compare the incidence of clinically relevant hypotension between my treatment and control group (ICU patients). In this study, I would allow the clinical team to treat hypotension as per their clinical judgement, but then the trick is to compare someone who got

    • 1 Liter of NS bolus,
    • vs 250 mL 5% albumin
    • vs increasing norepinephrine by 7mcg/min
    • vs starting vasopressin and so forth.  

    Any thoughts on how to compare these possible treatments for hypotension?

    Jeanetta Mastron · American University of Health Sciences

    Dear Vini Bains,

    You may wish to check out the following thread of Q&A that may help you, where I have posted on ratios in case/control studies


    MORE specifically to your question Dr./Professor Ariel Linden also posted  and refers to his RG posted paper that I believe will help you:

    "Using balance statistics to determine the optimal number of controls in matching studies"



    Jeanetta Mastron

  • Souad Djellali asked a question in Water:
    How to get the highest yield in plant extraction?


    Could you please tell me what is the best solvent which gives the highest yield in extraction of secondary metabolites from plants? and what is the best way: decoction, maceration, soxhlet, etc?

    I am trying to extract my plant in methanol or water, I want to know what is the best solvent: MeOH or water or a mixture MeOH/water? and what kind of compounds we could find in each extract?

    Thank you in advance.

  • Edgar Duarte Forero added an answer in Industrial Engineering:
    Has anyone a good reference about a textbook regarding the topic of VRP?

    I am designing a course for undergraduate students of Industrial Engineering about transportation. I am looking for a textbook which can be considered as a base for that course. The textbook should contain the theory and examples of topics such as travelling salesman problem, VRP, Clark & Wright, and some other classical heuristics.

    Thanks a lot in advance.

    Edgar Duarte Forero · Universidad Libre

    Thanks a lot to all of you. Your recommendations are very useful. I will be preparing the course, and I will share with you the corresponding results.

    Best regards,


  • Carl Alexander Sorensen added an answer in Physical Activity:
    Which is the simplest physical activity measure, but with good reliability?

    Which is the simplest physical activity measure, but with good reliability?

    Carl Alexander Sorensen · University of South Carolina

    Also, if frequency/intensity of PA is what you plan to measure, I would consider using consumer pedometers or fitness trackers (e.g., fitbit). Such devices are much less expensive than "gold standard"/professional grade devices (e.g., actical/actigraph), require no additional proprietary equipment, and data preparation requires much less specialized expertise than professional grade accelerometers. Additionally, a few studies have examined some of these devices relative to their more expensive professional counterparts and demonstrated acceptable reliability and validity.

  • Mariela Vásquez added an answer in Cognitive Assessment:
    Do you know if there are any research works on scales for the assessment of basic thinking processes in children or pre-adolescents?

    This could include such items as cognitive structures, logical and strategic reasoning, developing skills.  Even educational technology related to cognitive assessment could be helpful.

    I really appreciate your time, thank you,

    Mariela Vásquez · Universidad Católica de Santiago de Guayaquil (UCSG)

    Thank you so much E. Knight, very interesting, especially BVRT, that has to do with memory.  


  • Xiaoyu Zhao added an answer in Puromycin:
    Why two shRNAs have different results in establishing stable cell line?

    I want to establish shRNA KD stable cell line. I tried two shRNAs for each gene. However, I just can get stable cell lines from one shRNA. Another shRNA KD cells always die gradually after selection(after 4days puromycin selection, there are still several cells, but when I keep the cells in the medium with very low concentration of puro, in order to get more cells, but the cells die gradually). Could anybody tell me what's the problem?

    Xiaoyu Zhao · Stony Brook University

     To Alessandro, I used Lenti virus to infect the cells and the cells are adherent. I packaged the virus particles for each shRNA at the same time, using same protocol. I did not sequence shRNA since I just bought these shRNAs directly from Sigma, most of which are already validated. I also think the PuroR should be fine, since the shRNA are bought at the same time. The other group of shRNAs works very well.

  • Akira Kanda added an answer in Theoretical Physics:
    May gravito-electromagnetism be an alternative to Einstein's theory of general relativity?

    Gravito-electromagnetism (GEM) describes gravitation starting from the idea (suggested in 1893 by Oliver Heaviside and further developed by Olev Jefimenko) that there is a formal analogy between the gravitational and the electromagnetic phenomena.  This implies that - relative to an inertial reference system O - a gravitational field is characterized, in analogy with an electromagnetic field, by two vectorial quantities: the gravitational field Eg and the gravitational induction Bg.  The spatial mass destribution is the source of Eg  and the motion of the masses relative to O that of Bg

    According to GEM, a gravitational field is just like an electromagnetic field (Maxwell's equations) mathematically described by a set of four partial differential equations, the GEM-equations.   They describe how Eg  and Bg   vary in space due to their sources and how they are intertwined.  The action of a gravitational field on particles is described by a law analogous to Lorentz's force law: the force law of GEM.

    It has been shown that GEM can explain a number of phenomena (precession of planets and binary pulsars, gravity probe B experiment, ...) that are inexplicable in the context of Newton's description of gravitation what makes that GEM can be considered as a possible alternative to GRT.

    In line with the original idea of Heaviside GEM can be seen as an extension and a refinement of the "classical theory of the gravitational field", an extension that - besides the effect of the spatial distribution of the gravitating bodies - takes into account the effect of their motion.  GEM can theoretically be founded and explained by the theory of informatons. (https://www.researchgate.net/publication/268576021_GRAVITO-ELECTROMAGNETISM_EXPLAINED_BY_THE_THEORY_OF_INFORMATONS?ev=prf.pub)

    Let us still mention that GEM has been discussed within the context of general relativity by a number of authors and that it has been shown that  the GEM equations can be derived in the weak field approximation of Einstein's description of gravity.

    Akira Kanda · University of Toronto

    > A point mass (a particle), moving with velocity v (relative to an inertial reference frame O) in a gravitational field (Eg, Bg) tends to become blind for the influence of that fiield on the characteristic symmetry of its "own" gravitational field. If it is free to move, it will accelerate relative to its proper inertial reference frame O' with an amount: a' = Eg + (v x Bg).

    I presume that we are allowed to consider non em, non gravitational froce applied on the electric charge.

  • Marco Acosta added an answer in Orgasm:
    Do you have an articles about the evolutionary value of orgasm in the male and female human?


    Marco Acosta · Fundacion fadesco. Instituto del sistema nervioso

    Than you very much.

  • Karl Toppler added an answer in Casting:
    Can anybody tell me about the LVDT process during casting in aluminium alloys during solidification?

    I need to find out about the development of stress  during the solidification in casting process when load is applied at the same time.

    Karl Toppler · Australian Nuclear Science and Technology Organisation

    this could be an interesting in-situ neutron beam experiment using a strain-scanner

  • Jaime Leonardo Baez Presser asked a question in Impact Craters:
    Cataclastic deformation structures in sub-lithospheric diamonds. subduction origin?

     only? or........ http://www.lpi.usra.edu/exploration/training/resources/impact_cratering/SPApressure