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  • I. A. Buyanovskii added an answer in Metallurgy:
    What is the most suitable existing wear model in literature till now to calculate quantitative wear?

    I would like to calculate the quantitative wear at high temperature between copper and steel. so I am looking for best Wear model to calculate the quantitative wear.

    I. A. Buyanovskii · Blagonravov Mechanical Engineering Research Institute of Russian Academy of Sciences

    You can see any book of Russian tribologists.

    For instance in: Доценко А.И., Буяновский И.А. Основы триботехники. - М.:ИНФРА-М, 2014.

    Мy best wishes

  • Barney . added an answer in Protein Binding:
    What's the best way to maximize protein binding to my column/resin in order to purify a protein with an Ni-NTA column?

    I have done 2 purifications using a Ni-NTA column so far and each time we've noticed (based on my SDS-PAGE results) that lots of protein is collected in my flow-through (not binded to the resin).

    We've tried incubating the resin with the protein at room temperature, rotating for 2 hrs. We've also tried using a gilson minipump to pump our solubilized protein solution into a column at a flow-rate of 2 mL/min.

    Both procedures resulted in low yield of protein and lots protein located in the flowthrough.

    Barney . · University of Alberta

    Well I read a paper published last year from Bangalore that indicated they could purify protein solibilized from 100 mL of culture with 0.5 mL per resin. I'm doing the same thing and I haven't gotten a similar yield as they yydid.

  • Federico Svarc added an answer in Microemulsions:
    What is the importance of Ph of microemulsion in an EOR process?

    Which one is to be more preferred alkaline or acidic?

    Federico Svarc · fabriQUIMICA S.R.L.

     Sorry I did not finish the idea:

    Ideal pH should depend of nature of the surface active molecules used to extract, at least in principle.

  • Michael Schmitt added an answer in Self-Assembled Monolayers:
    Can anybody suggest me any protocol for preparing self assembled mono-layer of Silane in polystyrene micro-titre plate?

    i want to prepare self assembled monolayer (SAM) of silane molecules inside a polystyrene micro titre plate well. i was using the protocol given in http://www.sciencedirect.com/science/article/pii/S0003267003014740 research article. at first i got success but at the later attempts whenever i was trying to do the nitration the whole well turned white and lost its transparency. why this is happening i am not able to figure it out. so if anybody can suggest me better protocol it would be much helpfull. thanks in advance :) 

    Michael Schmitt · Universität des Saarlandes

    Dear Kumar,

    the attached link may help you to find a less harsh and more effective route for the first step of your synthesis. Unfortunately the second step the reaction described within the mentioned contribution is more than unlikely in this way (think about Sol-Gel-synthesis). APTES is a highly reactive silane which prefers to form mono-aminopropyl siloxanes especially if water and acid are present. A reason for the adhesion may be the change is surface tension of the PS by forming Nitro-PS and the surplus of acid still remaining attached to/into the polymer due to the fabrication. Why do you not reduce the Nitro-functionality to an amine?

  • Mariza Kluck asked a question in Informality:
    How can I change my email adress?

    My email adress have changed from mkluck@hcpa.ufrgs.br to mkluck@hcpa.edu.br

    I need to update this information.

  • André Vivan asked a question in ProModel:
    How I assign stochastic times in ProModel software?

    I'm building a production system model in ProModel software and I need to assign stochastic times to some of my resources (operators). So I'd like to know how I can do this. Thanks!

  • Gilberto Aboites added an answer in Immigration:
    Are there any publications about the relationship between immigrants' social contacts at work and in their leisure time?

    Dear all,

    I am searching for articles dealing with an association between immigrants' contacts to persons from the host country at work and in their leisure time. In the sense that more contact to natives at work leads to more contact to natives in leisure time.

    Many thanks in advance,


    Gilberto Aboites · Autonomous University of Coahuila



  • Yichen Liang added an answer in Quantum Dots:
    How does photoluminescence decay lifetime of PbS or PbSe quantum dots change by changing the ligand length on their surface?

    I want to know how does decay lifetime of PbS or PbSe QDs changes by changing the length of the capping ligand? Is it gana be constant or changes?

    Yichen Liang · Missouri University of Science and Technology

    In my opinion, longer ligands can produce better luminescence. However when the length increased to a threshold length, no matter how long the ligands are, no luminescence increment occurs.

  • Andile Ntuli added an answer in Lignin:
    Can anyone suggest best method for isolation of lignin?

    I am working on ligninolysis and want to estimate and analyse effects of various treatments on lignin. Can anyone suggest me method for isolation of lignin in which lignin undergoes least possible chemical, structural or compositional change?

    Andile Ntuli · Council for Scientific and Industrial Research, South Africa

    Depending on the starting material and the percentage of lignin in that material. There are many ways which include Acid-bisulphite cooking, Kraft cooking, Oxidation of biomass. Even though no particular method is known to remove all lignin content, a series of steps, combinations can be carried to remove lignin from biomass.

  • András Bozsik added an answer in Sustainable Rural Development:
    How might I assess the impact of water resources on socio-economic considerations?

    The water resource is a valuable assets for the community. If better water resource available it likely to influence agriculture, production,livestock, fish and human etc. But the problem is that quantification of all these impacts.

    So please help me getting the answer,

    András Bozsik · University of Debrecen

    Dear Subhash,

    Dear All,

    Your question is not really clear. Would you be as kind as specify it? However regarding the general water problem, the overuse and wasting of water by consumers and industry, mainly in developed countries and the pollution of clear water resources – surface and soil water – both by developed and undeveloped countries are the most important issues. Education is an efficient but slow tool against personnel overuse and waste.

     However - unfortunately – options against industrial overuse and pollution are simply limited because of the greed and confused interests of political leaders and capitalists.

  • Tony Nguyen asked a question in Micromanipulation:
    Which Micromanipulator do you recommend for Pronuclear microinjection?

    I am planing to do Pronuclear Microinjection. Could you give me recommendation for Micromanipulator?

    Do I need a electronic controlled device for this purpose, or would a manual/mechanic micromanipulator be suitable?

    Thank you.

  • Arnold Trehub added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Arnold Trehub · University of Massachusetts Amherst

    Alfredo: "I understood your theory as stating that the function of the neuronal mechanism of the retinoid space is described by a boolean network of autaptic neurons."

    This is a fundamental misunderstanding. I have never referred to retinoid space as a "boolean network of autaptic neurons". I have proposed the retinoid model to be a minimal theoretical description of a biological system of mechanisms composed of real neurons in the brain. The function of retinoid space is to give a creature a transparent brain representation of the world from a privileged egocentric perspective.

  • Oksana Shalygina added an answer in Venus:
    Does anyone know any good papers/books on planetary volcanism?

    Looking for useful references for planetary volcanism (volcanoes on the Moon, Mars Io, Venus etc). I need them to be as recent as possible.

    Oksana Shalygina · Technische Universität Braunschweig

    Hi Lucas,

    There is a recent paper (2015) about volcanism on Venus: Shalygin, E. V. et al (2015), Active volcanism on Venus in the Ganiki Chasma rift zone, Geophys. Res. Lett., 42, 4762–4769, doi:10.1002/2015GL064088.

  • Salvatore S. Mangiafico added an answer in Basic Statistical Analysis:
    Statistics - is it acceptable to transform data by transforming the values to the power of 3/2?

    I want to transform my data to achieve normality, but all the regular transformations have been unsuccessful. Transforming using the power of 1.5 (3/2) gives me normal distributed data. Is this an acceptable transformation to use?

    Transformed value =  value^(3/2)


    Salvatore S. Mangiafico · Rutgers, The State University of New Jersey

    Short answer: Yes.  People often use Box-Cox transformation or Tukey Ladder of Powers transformation, both of which an give fractional powers.

  • Lorenzo Lazzaro asked a question in Invasive Species:
    How can I use the Boyce index to obtain a robust threshold to transform the continuous output of the model to P/A values in case of invasive species?

    I am working on SDMs in case of Invasive Species. I am using the bioclim algorithm in dismo package in R. I used the Boyce index for the model evaluation, and i would like to use it also to find a reasonable threshold to transform the continuous output of the models into P/A values. I usually used AUC, but they seem not reliable in case of Invasive species. How should I proceed?

  • BA Haider added an answer in Flight Dynamics:
    Are aerodynamic relations in performance books accurate for aerodynamic modeling?

    hi dear researchers,

    i want to model UAV aerodynamic,

    i use relations in part 6 roskam  or relation in performance books?

    if any researcher have another source please send me.

  • Olawale Olarewaju Ajibola added an answer in Ferrites:
    Aren't there artificial materials that are ferromagnetic and light, unlike silicon steel & ferrites?

    That would make electrical machines much lighter:

    (1) making them easier to transport and install, and also

    (2) adding lesser weight in mobile platforms like electric vehicles.

    Inductors and transformers would also be much lighter.

    Olawale Olarewaju Ajibola · Federal University Oye-Ekiti

    See if the attached file is useful

  • Yvonne Carroccino added an answer in Evidence Based Practice:
    Can anybody recommend good books on evidence based practice, requesting to suggest books to those who are beginners in exploring EBP?

    evidence based medicine

    Yvonne Carroccino · Southern New Hampshire University

    Polit & Beck, great for intro to EBP and developing a project.

  • R. Mark Bradley added an answer in Glass Substrate:
    How can we explain the increase of grain size with the increase of film thickness?

    In2S3 films were deposited on soda-lime glass substrates by spray technique for different thicknesses. I have found that the grain size increase with the increase of film thickness? How can we explain this result? Give me some references if it is possible.

    R. Mark Bradley · Colorado State University

    @Sergei --- Is it understood why this is true? 

    Best regards,


  • Stefan Schwarz added an answer in Otitis Media:
    Does anyone have experience in the identification of microorganisms of the genus Arthtrobacter (especially in human clinical materials)?

    Sometimes I find the members of this genus in clinical material (especially with otitis media or by. externa) and I do not know their clinical significance and even I do not have adequate and reliable diagnostic scheme.

    Stefan Schwarz · Friedrich Loeffler Institute

    Sorry, Peter, no experience with these bugs in my lab,


  • Moustafa M. Abdelfattah El-Fadl added an answer in Phosphates:
    What is the lowest phosphate concentration that can be measured in water?

    We have difficulties in measuring very low ortho-phosphate concentrations. Maybe you know of a method or a laboratory that can help.

    The questions we have are: 1) Is there a reproducible, accurate method to measure ortho phosphate values below 10 ppb in tap water, fresh water and/or seawater? 2) What is the lowest phosphate concentration that can be measured in water? We search for a method able to measure 1 ppb and preferably lower values.

    The rationale to measure very low phosphate concentrations in water is to be able to evaluate to what extent the phosphate needs to be removed from water for prevention and control of biofouling of membrane systems. Biofouling is a major problem caused by biofilm formation in spiral wound membrane systems used for production of high water quality (from a broad range of water sources, such as e.g. seawater).

    Moustafa M. Abdelfattah El-Fadl · Desert Research Center

    The maximum permissible concentration of phosphate ions in surface water is 1 mg/l (Dojlido and Best, 1992).

  • Rose Filoramo added an answer in Immunology Techniques:
    What is the lowest pH you would recommend using in IP injections--that will not cause pain to the animal?

    I am injecting mice IP with the drug vinpocetine. Combing through the literature--it appears that most researchers use a vehicle of saline acidified with HCl to a pH between 4 and 5.5. These seem rather low for IP treatment. The other option I have seen is to use a low dose (~40ul) of 100% DMSO. Any suggestions of what to do or other things to look up? Thanks!

    Rose Filoramo · Harvard University

    I am looking into some possibilities with acetic acid and cyclo-dextrin inclusion complexes--let's hope this is not too bad of a rabbit hole!

  • Abdunasir Sideeg asked a question in Formal Semantics:
    Is there any precise FORMAL diagnostic for identifying ‘intersective adjectives’ [I-adjectives] and ‘non-intersective adjective’ [NI-adjectives]?

    Formal Semantics.

  • Andy Wu asked a question in Laser Microdissection:
    Is it possible to do laser microdissection with bone cryosection samples to extract mRNA?

    I want to isolate specific areas of the knee joint (both cartilage and bone) for gene expression analysis using qPCR. From what I've researched, it seems that it is best not to fix the samples if I want to do frozen preparation for bone LMD. But in order to get good cryrosections, decalcification of the bone sample is probably necessary and this would require fixation for the RNA to survive the decalcification, right?

    If anyone has any experience with this, please do share your comments. If possible, I would like to know what preparation steps work for bone/cartilage samples and how much RNA can I expect to isolate from LMD samples. 



  • David Farringdon Spencer added an answer in Ethanol Precipitation:
    I am losing almost 50% yield in my RNA EtOH precipitations. Suggestions?

    Here is my typical protocol:

    1) To 200 ul of ~1.2 nmol of 95 bp RNA, I add...

    1 ul 20 mg / ml glycogen as a carrier
    .3 M final concentration sodium acetate, pH 5.2 at room temp
    .01 M final concentration MgCl2 (Bitesize Bio recommendation for <100 nts)
    500 ul (2.5 volumes) 100% EtOH

    2) I then freeze at -80C for 1 hr
    3) Spin down RNA at 4C 30 min ~21,000 g
    4) Decant supernatant
    5) Wash pellet with 75% EtOH -- I do not resuspend pellet or invert tube -- I simply add 75% EtOH that has been stored in -20C -- then spin down at 4C, 21,000 g for 10 min

    6) Dry in speed vac 3 min
    7) Resuspend in appropriate buffer or MQ water
    8) Nanodrop

    I am usually losing between 40-60% of my RNA for some reason. I'm not sure what else to do. Please let me know if you all out there have any advice.

  • Vadym Dolia asked a question in Gravitational Field:
    Where you can quickly analyze data variable gravitational field?

    Hello Everyone! Tell me please where you can quickly analyze data variable gravitational field in various parts of the Earth.
    Sincerely Dolia Vadym.

  • Samuel Pagliarini added an answer in Verilog:
    Can I use signed bit elements in verilog?

    Actually the architecture involves a subtractor and I need it to be signed. Is that possible using verilog?

    Is it possible to add a subtract or in the code which should be signed and could possibly do signed subtraction using verilog 

    Samuel Pagliarini · Carnegie Mellon University

    Two's complement will surely work, but it has caveats. You may have to convert to/from and comparison operations are no longer straightforward. 

    You can take care of the sign yourself by using this 'trick':

    {c, s} = a + b;
    the sum of a+b will be put into s, whilst the carry will be put into c. It works the same way if you have a-b, in that case c becomes the borrow bit.

  • Yin Li asked a question in Phonons:
    Is there any free phonon software that is able to calculate IR spectrum?

    Hi everyone,

    I want to calculate IR spectrum of my crystal. I first optimized the structure using ab initio codes. The next step is to calculate the vibrational spectra. Because the vdw-correction was involved when geometry optimization was performed, the phonon code based on DFPT method can not proceed. As far as I know, some other codes such as phonon, phon, phonopy that are programmed on the ground of displacement method are also able to give IR spectra. I learned that in some cases, only the frequency can be calculated, the intensity can not be obtained. Does anybody know any free phonon software that can both calculate the frequency and intensity??

  • Noor Ul Hadi added an answer in Partial Least Squares:
    Is there any goodness of fit index for PLS?
    I am more familiar with SEM tools than PLS. On the other hand, one student I am supervising wanted to use PLS on account that it has significantly smaller sample size requirements than SEM. However, I have my own misgiving with the lack of goodness of Fit statistics in PLS (to my knowledge). Is there any goodness of fit statistics (or its equivalent) in PLS?
    I would like opinion from both PLS and SEM users on this matter.
    Noor Ul Hadi · University of Kuala Lumpur

    Since the objective of PLS is to maximize variance explained rather than fit, therefore prediction oriented measure such as R squares are used to evaluate PLS models.

  • Rajat Pradhan added an answer in Foundations of Physics:
    Do the effects of mind on matter as demonstrated in the experiments of Radin et al (Physics essays 2012 & 2013) herald a new scientific paradigm ?

    This refers to the recent experiments of Radin et al :

    1) D. Radin, L. Michel, K. Galdamez, P. Wendland, R Rickenbach and A. Delorme
    Physics Essays, 25, 2, 157 (2012).
    2)  D. Radin, L. Michel, J. Johnston and A. Delorme, Physics Essays, 26, 4, 553 (2013).

    These experiments show that observers can affect the outcome of a double slit experiments as evidenced by a definite change in the interference pattern.

    It requires urgent attention from the scientific community, especially Physicists.

    If these observed effects are real, then we must have a scientific theory that can account for them.

    Rajat Pradhan · Utkal University


    Any statement in the science cannot be outrageous; the statements can be only true, false and questionable, including uncertain.

    I must support this statement of yours for its correctness.