Q&A

ResearchGate Q&A lets scientists and researchers exchange questions and answers relating to their research expertise, including areas such as techniques and methodologies.

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• Can anyone provide insights on Betaray?

http://themindunleashed.org/2013/12/glass-sphere-might-revolutionize-solar-power-earth.html

Reference to the up-mentioned link, does anyone know if it is being commercially used anywhere and what are the outcomes. Where can I find articles related to its business implication? I tried google scholar, not much info available

Mohammad Nikkhou · Khorasan Institute of Higher Education

hi

http://techacute.com

If a polynomial P(z) of degree n omits w in |z|<1, show that P(z)-(1-e^{ih})zP'(z)/n also omits w in |z|<1?

If a polynomial P(z) of degree n omits w in |z|<1, show that P(z)+(1-e^{ih})zP'(z)/n also omits w in |z|<1 for every real h. I know at least two proofs of this result, one follows by using Laguerre's theorem concerning the polar derivative of a polynomial. I want to find the direct proof of this result with out using any known Theorem.

Miodrag Mateljević · University of Belgrade

It seems that you should give more details. Is this known
result? Is the hypothesis that h is real? For example, the set
$1-e^{ih}: h \in R$ is the circle $K(1;1)$.

One can try to use induction  or Bernstein inequality with Argument Principle.

How to transport fat tissue for isolation adipose derived stem cells (ADSC) from clinic to lab ?

Hello,

I'm trying to transport fat tissue after surgery and lipoaspiration to laboratory. The aim of my experiment is isolation of adipose derived stem cells(ADSC) and I need to maintain them undifferentiated. I read a lot of about it and there are two different recommendations

1. dry ice and buffer or

2. room temperature and medium

Thank You

Jasmin S. Nurkovic · State University of Novi Pazar

Hi Aleksandra,

And we have worked as Katarzyna, and did not have problems.

Best :)

Is there a link between HGH deficiency and depressive symptomology?

It has been seen that brain injured patients with HGH deficiency often suffer with depressive symptomology. My interest is in whether anyone has done a study on this, as this is part of a working hypothesis of mine, that HGH may play a role (through the proliferation and differentiation of stem cells) in maintaining and repairing cognitive functioning,(specifically in the areas of attention, memory) and emotions.

Another hypothesis which is linked to this, is that BDNF and HGH work together in different ways with regards to neurogenesis and neuroprotection, but that both are required to restore functioning. Has anyone done any studies on both of these factors together (there are a great deal of studies on BDNF, but none that I can find that look at both together)?

In the case of both hypotheses, I have not been able to find studies specific to what I have mentioned.

Any comments or input would be appreciated.

Colin A Hendrie · University of Leeds

Can you provide a reference for the 'exceptional study' that you refer to  please?

The caution that must be exerted here is because it seems that about 40% of depressed patients respond no matter what you do and that response rate seems to be independent of what it is that is actually done - including just giving placebo (see Fig 2 Khan, A., Faucett, J., Lichtenberg, P., Kirsch, I., & Brown, W. A. (2012). A systematic review of comparative efficacy of treatments and controls for depression. PloS one, 7(7), e41778. - linked here  http://img.photobucket.com/albums/v462/chendrie/Khan%20fig%202.png

Hence my interest in the STAR-D approach since one explanation for these data is that they may be no more than an additive placebo effect (40% responding in Level 1, 40% of those remaining responding in Level 2 etc).

Can someone explain the attitude: "Mathematics is in everything"?

Specifically, can someone explain the attitude: "Not everything in mathematics, but mathematics is in everything."

Peter T Breuer · Birmingham City University

Why?

Yes, I am a little bruised with seeing so many unmotivated and somewhat linguistically challenged and really trivial questions from this source spotting through my feed: Does anybody know who is the creator of philosophy? How do you imagine the means of transportation people in the future? Does anyone know how we can most easily recognize mathematical talent? Does anyone know why the majority of H. Matis oil on canvas is located in Hermitage museum? Does anyone know: Is the award N. Lobachevsky largest prize for mathematics in the world? ... and on and on for sixty really objectively childish questions. It's like chinese water torture.

Everything in the Universe Is Made of Math – Including You ...
4 Nov 2013 - This might not be that important except that colleagues perceive this ... The idea that everything is, in some sense, mathematical goes back at ...
Mathematical universe hypothesis - Wikipedia, the free ...
en.wikipedia.org/wiki/Mathematical_universe_hypothesis
Thus, he reasons, it is preferred over other theories-of-everything by Occam's Razor. ... mathematical structures are a priori given equal statistical weight,' there is no ... But a few surprising examples of mathematical abstraction notwithstanding ...
Is the Universe Made of Math? [Excerpt] - Scientific American
www.scientificamerican.com › More Science › News
10 Jan 2014 - Math, math everywhere! But ... Not just aspects of it, but all of it, including you. ... Everything in our world is purely mathematical – including you.
The Universe Is Mathematics, Physicist Says - LiveScience
www.livescience.com/42839-the-universe-is-math.html
30 Jan 2014 - In Tegmark's view, everything in the universe — humans included — is part ... But if the universe really is mathematics, he added, "There's nothing we can't, ... world shows that math exists in reality, not just in the human mind.

Please remove "mathematics" from the list of topics. This is not mathematics. Mathematics is not involved in any of your questions. Philosophy, perhaps, though I hope not.

Come to that, the topic is not "specificity" or "attitude" either, but then those words don't mean anything as subject delimiters, so you can harmlessly add them! Also "egg hunting".

• How can I compute "direct axis subtransient inductance" easily?

10.00. How I can compute "direct axis subtransient inductance" easily?

L"d=Ld-K^2(Mf^2 LD+LD MD^2-2MD MR MF)/(LF LD -MR^2)

Mohammad Kargar · Khorasan Institute of Higher Education

hi

Is there a good blunting enzyme to blunt 3' overhangs?

What I am doing is pretty straight forward. I am cutting out a fragment with two restriction enzymes. Then enzymes are needed to chew away the two 3' overhangs so I can circulate my plasmid afterwards. I've tried with pfu but with no success in getting colonies after T4 ligation. Could you please help checking my experiment conditions and please indicate any improvements and suggestions? T4 DNA polymerase or Large Klenow fragment?

End-cleaving ingredients: gel purified double digested plasmid 10ul (41.1ng/ul), pfu DNA polymerase from Promega 1ul, 10x Pfu buffer 10ul, H2O 79ul. Incubate at 72℃ for 20min. Purify according to Qiagen pcr purification kit protocol, final step elute in 15ul H2O.

Then I performed T4 ligation: 2x ligation buffer 5ul,  4ul (out of 15ul) eluted fragment, T4 ligase 1ul. Incubate at 4℃ overnight. Transformation and no colonies.

Yuan-Yeu Yau · Northeastern State University

Take a while, just checked back.

1. Thanks, Theo for the response (3 days ago).

2. Jiexi, I used to use 4C overnight for my blunt-ended ligation. They seemed ok, although I only got a few colonies (not a bunch). But, as long as one of them works, it's done.

3. Could it be that your linear blunt-ended vector ligate back into circular form (even before it takes in the insert) during ligation process if you have the phosphate group at the ends?

• Should clinical psychologists working in hospitals wear uniforms?

Most clinical psychologists working in hospitals wear their own clothes.   Confronted with risk of infection they wear protective clothing.

An increasing number of psychologists are forced to wear staff uniforms.

Should clinical psychologists working in hospitals wear uniforms?  Does it affect the therapeutic relation?  Looking for literature on this topic.

Peace Iheanacho · University of Nigeria

Overalls for protection is not bad and of course, a name tag for identification.

• Do mindful awareness techniques/practices improve executive functions in children with learning disabilities?

Is anyone doing or has done a comparative study to examine the efficacy of mindful awareness practices with other psychological treatment techniques such as Remedial training, Cognitive training and CBT in children with learning disabilities? I am looking for literature on this topic.

• Which one is right to describe Hafele-Keating experiment (twin paradox)? SRT, GR, absolute referential, modified clock frequencies?

Is there a distinction of Sagnac effect between SRT and GR or absolute referential is enough? Are the clocks runing at same frequencies?

Stefano Quattrini · Ordine degli ingegneri della provincia di Ancona

Kåre

Thanks a lot for the Link

Why Al2O3 liner cracks when used for evaporation of copper?

I am curious to know the physics behind Al2O3 liner cracking when used for evaporation of copper at high temperature in PVD.

Tasnuva Ashrafee · Old Dominion University

Can anyone suggest an operational definition of the power of an individual (e.g. person or computational agent) in a social network?

I am writing a computer program that implements an abstract social network of inter-communicating individuals (so a multiple agent system) and I want to be able to compute for each agent in the network of computational agents its individual POWER. I mean actual power, not e.g. power attributed by reputation or constitution. Thus does the mayor of the city of Metropolis have more or less power than the person about to detonate a bomb that will collapse a dam and flood the city? In the UK does the Prime Minister David Cameron have more or less power than Queen Elizabeth or Ian Hislop, editor of the famous satirical magazine Private Eye? By how much?

TO CLARIFY, although the suggestive examples I have given involve human beings [OK, maybe there is some slight doubt about Ian Hislop...] I am looking for (and not yet finding) an ALGORITHMIC means of calculating the "size" of some dynamic attribute reasonably called "power" for a COMPUTATIONAL agent that is a member of a dynamic network of COMPUTATIONAL agents.within a computer. All help much appreciated and duly acknowledged in any consequent publication(s)!

James Doran · University of Essex

I'm prepared to believe that Python is a neat language. But I am more familiar with C, there is useful existing code available, and there are the usual syntactic sugar v efficiency arguments. Not a big issue, really...

How compatible is pyrolytic graphite liner for high temperature copper evaporation?

I have following questions regarding the use of pyrolytic graphite liner for high temperature copper evaporation in thin-film application.

- reaction or deformation of the liner when copper is melted at high temperature (1400 deg C) in PVD process?
- contamination due to carbon?
- reaction with moisture and out-gassing of oxides?

Tasnuva Ashrafee · Old Dominion University

Thank you so much :)

What is the best technique that the scientists reached to protect metals from corrosion?

Due to the multiplicity of techniques used to protect metals from corrosion Is there   a high quality and low cost ways to protect metals from corrosion ?

Rana Afif Majed Anaee · University of Technology, Iraq

This is depends the structure which you want to protect it. For example, in the case of pipelines in soil you can use cathodic protection with coating. In the case of internal tanks, you can use anodic protection. In the case of closed systems, you can use inhibition... etc...

• Idrees Ahmed asked a question in Reconstructive:
Is there any technique to reconstruct the chain if some records are removed?

For example there is linked chain of hashes of a document. some of consecutive hashes are deleted how to recover or reconstruct the chain.

Cancer a mere matter of luck? Or is there something under-appreciated?

It has been all over in the news lately: The majority of cancer is obtained by bad luck, not by lifestyle or inheritance. See attached.

Really? The data appear solid and they make sense, but the conclusion seems a bit premature: the observations are based on established risk factors in the USA and I assume (let the experts please come forward!) that these risk factors are based on occurrence. This means we do not see all those cases where the patient's immune system adequately takes care of the anomaly.

How does occurrence of cancer relate to failure of the patient's immune system, and can we monitor this based on adequate biomarkers? How will the statistics and the conclusions change when this factor is included in the analysis?

Andrey Luchnik · Russian Academy of Sciences

Dear Ijaz!

You asked vague question not based on current knowledge: "Do you agree that the reversion of cancer cells occurs routinely in vivo, independently of mutations or is this phenomenon cited by Bjorn, an artifact of in vitro systems?"

Reversion of cancer cells never occurs in vivo. Because all of them contain chromosome aberrations related to chromosome instability of cancer cells. Chromosome rearrangement equals to 'origin of species'. Because all of the novel species arise due to chromosome rearragement (not mutations of genes).

However apaptosis (not necrosis) of cancer cells "occurs routinely in vivo" as has been discussed within this topic in my posts.

The matter is that cancer cells arise in everyone of us every several years. But those of us who still possess healthy subconsciousness (hypothalamus 'feeling') get rid of cancer everytime untill the loss of healthy instinct of hypothalamus.

And while I speak to you and you to me friendly in this discussion, our potential cancer cells die permanently. In other words, this "occurs routinely in vivo" as you formulated.

• What is the better organic coating to prevent from the marine corrosion?

Several organic coating exist based on epoxy, benzoxazine or other high performance thermosets, blends and particles reinforcements are also used to enhance the anti-corrosion properties. My question is: among these multiple choices what is the better organic coating used in naval industry?

Rana Afif Majed Anaee · University of Technology, Iraq

You can use polymeric coatings.

Can someone help me to identify this plant?

Can someone help me to identify this plant?

Nasser Belboukhari · Université Tahri Mohamed, Béchar

i think this specie is from borgenavea family , it is elizaldia

• Is there a solid counter-argument against Dingle's old objection to Relativity Theory?
Herbert Dingle's argument is as follows (1950):

According to the theory, if you have two exactly similar clocks, A and B, and one is moving with respect to the other, they must work at different rates,i.e. one works more slowly than the other. But the theory also requires that you cannot distinguish which clock is the 'moving' one; it is equally true to say that A rests while B moves and that B rests while A moves. The question therefore arises: how does one determine, 3 consistently with the theory, which clock works the more slowly? Unless the question is answerable, the theory unavoidably requires that A works more slowly than B and B more slowly than A - which it requires no super- intelligence to see is impossible. Now, clearly, a theory that requires an impossibility cannot be true, and scientific integrity requires, therefore, either that the question just posed shall be answered, or else that the theory shall be acknowledged to be false.
Sergey Shevchenko · Institute of Physics of the National Academy of Science of Ukraine

Stefen,

"...This illustrates the falsity of Einstein's conception of time...."

Yea, there is an [Einstein’s – as many people say] definition of the time: “Time is what clocks show”. But if somebody gathers all clocks on Earth in one place and resets them to “zero”, after some time interval all clocks will show different “times” – and nobody who say that Time is what clocks show will not able, of course (if (s)he, of course, hasn’t problems with the adequacy) to say something as “just this clock show time”.

So quite more correct is the definition “Time is what clocks never show”…

Cheers

What should be the next step in PCR optimizaton when smear is seen in the wells loaded with the PCR product?

What can be the best possibility to obtain a clear sharp band after getting a smear in a PCR reaction?

Carmen Leitch · University of Maryland, Baltimore

I agree that it's probably non-specific amplification and you should increase annealing temperature first. You may also want to run some of your (non-PCR'ed) template on a gel.. if you see smearing from that, it's indicating that your template is probably degraded.

I can't identified this parasite or something else?

I have collected from lizards

Hana soualah alila · Badji Mokhtar - Annaba University

I think that the circul in the middle is biger that the normal one !!!

Why did DNA (pcr product) remain in the some gel well ( the picture)?

The upper band are pcr products after restriction enzeme(kpn1) and the down band are pcr product( straight)

Yuan-Yeu Yau · Northeastern State University

Hi Mohsen,

1. See the Point 5 of this attached handbook ( "Troubleshooting Guide for DNA Electrophoresis" ) for 'DNA remains in the gel'.

2. They suggest: Always heat these samples with SDS at 65°C for 10 min, chill on ice, spin down and load, if add SDS. (See the yellow highlight).

What is the value of resistivity of zinc oxide nanoparticles?

In fact this the first time I have had to use zinc oxide nanoparticle solution and it was expected to have higher resistivity compared to the deposit zinc oxide by RF sputtering. So if you can help me with the right value and the right conditions to use this ink, it will be appreciated.

Abdelhalim Zekry · Ain Shams University

Dear Noura,

Zincoxide is a conducting oxide with n-type conductiity. It behaves interinsically as a semimetal. From the principle point of view, the electrical characteristics depend on the degree of crystallinity of the material.The material can range from amorphous to fine grained to large grained poly-crystalline to single crystal structures. The resistance of a polycrystaline material is that of the bulk and grain boundaries. In case of  high conductivity bulk, the resistance is controlled by the resistance of the grain boundaries.

In case of polycrystalline thin film material, the the sheet resistance of the film will increase by reducing the grain size and decrease by increasing the film thickness.

In case of sputtering the produced as grown film or with low temperature annealing will produce nearly amorphous film and hence probables the highest  sheet resistance for the same film thickness. I find that your results are consistent with the principles underlying the conduction theory of  crystalline films. I do expect that the nano particles have sizes greater than those resulting from sputtering without high temperature treatment.

wish you success

Can anyone suggest B cell markers which could be helpful for B cell separation from whole blood of carp (Teleost fish)?

I need to separate B lymphocytes from blood and maintain a cell line of it. Regarding that how should I proceed with B cell separtion from whole blood of a teleost fish of Cyprinidae family. For that I need to find out certain B cell surface specific markers based on which I could go for cell sorting. If anyone could suggest me B cell surface markers specific to carp family and from where can I procure it (under which brand), it will be helpful. Through literature, I do know certain carp Immunoglobulin positive B lymphocyte markers but I am not sure, whether those would work in my case and secondly, from where should I order.

Joseph Caruso · Florida Atlantic University

Since you don't know which markers to use, you may want to look for a anti-IgM vs. this or other teleost species, as long as it's mu chain-specific.  This would work to target naive (i.e. unstimulated) B cells.  You may also care to check out recent work on IgD in lower vertebrates.  Some investigators (Flajnik and others) have shown IgD in many fishes.  If you want to assay total Ig-bearing cells, you could also look for an antibody that is heavy-chain specific vs. IgY (or its equivalent) in teleost fishes.  I'm suggesting you use anti-Ig antibodies, because these usually cross-react with all members of a given lower vertebrate group.  I've had to make my own antisera to work with reptiles, but I've also found evidence suggesting cross-reactivity with other species in the group.  If you're looking to find anti-CD molecules as is common in conventional Immunology, I have no idea whether specific B cell markers have been described in teleosts.  If they have, you could try one of these. Good luck! JPC

Can a threonine residue suffer alkylation?

A threonine residue can be alkylated during a alkylation process using iodoacetamide if occurs overalkylation in the protein?

This reaction does not appear to be mentioned as far as I can find, although a reaction with methionine was mentioned (http://www.ncbi.nlm.nih.gov/pubmed/15912474). And of course, iodoacetamide is usually used to a alkylate cysteine.

• Marković G. Đoko asked a question in Philosophy:
Does anybody know who is the creator of philosophy?

Is the creator of science at the same time and the creator of philosophy?

• What is your opinion of Building Information Modeling?

The innovative process constructs a database assembling all of the objects needed to build a specific structure. Instead of using a computer to produce a series of drawings that together describe the building, BIM creates a single illustration representing the building as a whole.

Amir Causevic · University of Sarajevo

Building Information Modeling is framework for structural design that provides a thorough understanding of architectural structures and introduces a new framework that revolutionizes the way building structures are designed and constructed.

• In which areas of human activity computational intelligence plays most important role nowadays?

Most of modern systems are complex and include subsystems and components,  that are inﬂuenced by human factor. For example Artiﬁcial Intelligence has been of use in medicine primarily through the adoption of expert systems that aid in
diagnosis .

Barbara Sawicka · University of Life Sciences in Lublin

Digital technology is nowadays an area completely interdisciplinary knowledge about the face. Its issues formed on one side by hardware description languages, and on the other by a programmable logic modules, go ahead may be included in both the Computer Science, Electronics and Telecommunications. Today's digital circuit design techniques rely not only on submission of the available components, but rather on the process of formal, abstract design specifications in the corresponding hardware description language (HDL - Hardware Description Language) and to transform this specification using a variety of computer-aided design tools CAD (Computer Aided Design).

• Spiros Koutandos asked a question in Schrodinger:
What is the nessecary condition for solutions of equation to form equipotential surfaces in space?

For example for Laplacian in Schrodinger equation the solution is of the form psi=f(r)F(cos^2theta) so we may obtain the radius as a function of theta to be positive. What if it becomes negative? We all know of the lobes being created.

• How far can one get with analogies in theoretical physics?

Many a great theoretical physicist have gone on to explain their work qualitatively to the public, often times by virtue of analogies.

Now, I know analogies and qualitative explanations can be misleading if not presented correctly. Having a little background in mathematics (basic ideas in tensor descriptions of space-time etc.) I realize some of these analogies presented to me in the past are very misleading, while others are almost as good as a conceptual "one-to-one mapping" (so that understanding of the analogy leads to an almost perfect understanding of the concept)... almost as if the analogy belongs to the same abstract category as the concept to be explained.

I would just like to know (though I guess there is no exact answer): how far can one get to a full understanding of theoretical topics with qualitative explanations. Or, on a more pessimistic note: is it worth explaining things like general relativity, quantum mechanics, and string theory qualitatively and by analogy for any other purposes than "sensational" science?

Mohamed El Naschie · Alexandria University Alexanderia Egypt

TRULY AMAZING JUNG SCIENTIST . THANKS TO ALL OF YOU KEEPING OLD WOOD LIKE ME INTERESTED IN LIFE