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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Which tool is appropriate for the development of a systematic review question?

I am formulating and defining my research question for a systematic review (subject: dementia and singing) and expect to obtain both qualitative/quantitative/mixed methods studies. I don't think there will be enough to limit the review to one type or the other.
What type of tool would you use to formulate your question? The more I look at it PICO seems too rigid, but would SPIDER be appropriate even when included mixed methods?

Nguyen Phuoc Long · Ho Chi Minh City Medicine and Pharmacy University

Hi Marianne,

PICO(S) or SPIDER are goods tool to build a good research question (qualitative or quantitative method). Nevertheless, I think we don't have to strict on that in case of conducting a systematic review and meta-analysis. Key words are the most important. With good key words, we will have a good chance to collect all relevant evidence for our research question, then we can classified it into sub-groups to perform further analysis specifically.

This may be a good example for you:

http://aop.sagepub.com/content/41/11/1770.full.pdf+html

• Asanka Waga Arachchige asked a question in Dolphins:
Hi is there anyone familiar with designing mooring dolphins or breasting dolphins (pile supported)?

I am designing a breasting dolphin and in the difficulties of pile arrangement to minimise the axial tension in the piles. if any of you have ideas or resources please forward me...

thanks

Asanka (singapore)

asankaeng1@gmail.com

• Is there any "standard" quality assessment (of included studies) guideline for systematic review and meta-analysis of laboratory studies and modeling?

Dear scientists,

Is there any "standard" quality assessment (of included studies) guideline for systematic review and meta-analysis of laboratory studies and modeling?

For example:

Several preclinical neuroprotective drug development studies(*) used the same quality assessment method developed from the recommendations of this article:

Recommendations for standards regarding preclinical neuroprotective and restorative drug development (http://www.ncbi.nlm.nih.gov/pubmed/10583007)

Thank you.

----------------------------

(*) include:

http://www.nature.com/srep/2015/150120/srep07790/full/srep07790.html

http://stroke.ahajournals.org/content/35/5/1203.long

http://stroke.ahajournals.org/content/32/10/2433.long

Ricardo Matias · Instituto Politécnico de Setúbal

Hi Nguyen,

Sorry if these links weren't of any help; to look at studies in a SR or MA, like RCTs you could use tools such as CONSORT that propose standards of reporting trials, or STROBE for observational studies, STARD for diagnostic accuracy studies, etc.

If by 'modeling' you mean musculoskeletal modelling I would suggest you the attached link!

Again, hope it helps!

Does anyone have any experience in imaging human Lamina Splendens?

The uppermost layer of hyaline articular cartilage is called Lamina Splendens. This film-like layer is seldom seen arthroscopically and various optical and electron microscopic imaging studies have shown conflicting morphology and structure. Considering its location there is no doubt that Lamina Splendens has extremely important articular function as it provides a very low friction lubrication surface and contains lubricant and collagen fibrils which run parallel to the surface of articulation. This surface zone layer is likely to play a key role in maintaining the mechanical response of articular cartilage to load.

Ahmed Elmesiry · Animal Reproduction Research Institute

i have a research trial these days on Lamina Splendens on the joints of horse and donkeys using TEM but it is not published yet.

Does anyone know about polyamide 66 (Nylon66) Hansen solubility parameters (HSP)?

There are different values reported in the literature!

The strange thing is that formic acid is an excellent solvent for PA66, but all the reported HSPs are far different from those for formic acid. The R-value (gyration radius, dissolution distance) for formic acid with respect to reported PA66 HSPs is even greater than two, but it dissolves PA66 readily! While, regarding HSPs, it should not dissolve!

Any explanation/suggestion?

Amit Dharia · Transmit Technology Group, LLC

OK.  Does not matter.  Nylon 66 and Formic acid has too solubility parameters difference of less than 2 and formic acid will swell and Dissolve Nylon 66.  In some cases rule of thumb will not work, especially when Hydrogen binding is too strong.

Why a protein cannot be stained with nothing?

Does anyone know why a protein cannot be stained at all? I've tried staining it with Coomassie, silver and zinc-imidazole (reversible staining). I'm working with an alpha-amylase of about 250 KDa... it's huge... I've already concentrated it and In order to identify it I always perform a zymogram, and I can always see my amylase on the zymogram, but I can never see it on a SDS-PAGE... Any idea? Is there any information about not stainable proteins?

Viktor Y Butnev · Wichita State University

According to uniprot.org database alpha-amylase from Streptococcus infantarius has molecular weight ~75 KDa (678 amino acids). If the active protein is a trimer (250 KDa) you need to make sure that you don't have any protein dissociation during your extraction / concentration steps. If it is dissociated for 75 KDa subunits you can loose much of your protein on 100 KDa MWCO Amicon Ultra-4 filter device during the concentration step. The SDS-gel will also lead to subunit dissociation showing 75 KDa protein.

• Sana Khullar asked a question in Neurobiology:
Hi, I'm currently researching dreams as an experimental model for psychosis. Any must read papers apart from research by Hobson and Solms?

I understand that there are phenomenological and neurobiological similarities between the dream state and positive psychopathological state of schizophrenia or psychosis in general. Any fresh perspectives on this?

How can I prevent possible hot shortness problem during casting / hot rolling after adding 0.05% Sn into the steel composition?

There are some papers about Sn usage in non grain oriented electrical steels. Sn in steel promotes grain boundary segragation during final annealing by restraining the recyristallisation which can help decreasing core losses. Unfortunately, in steelmaking / hot rolling conditions,Sn strongly promotes the hot shortness. Thus, what are the possible options to prevent hot shortness caused by Sn addition? Does the proper Ni addition in steel in order to form Sn-Ni intermetallics help or not?

M. E. H. Shalabi · Central Metallurgical Research and Development Institute

the sulpher in steel caused the hot shortness and phosphoure  caused cold shortness  you must decrease the sulphur in steel before treatment

• Mien Sinaga asked a question in Median:
What is the important side to design median u-turn openings?

median u-turn is my topic for my final examination and i got confused of this, so i need help for tell me more about u-turn facility.

• How can we formulate Loschmidt's paradox in the quantum domain?

This question was inspired by the answers and discussions around a previous question,

Assume for simplicity a monoatomic gas closed in a container. The container walls are assumed completely reflecting and totally opaque to heat. Assume that all the atoms are identical and spherically symmetrical.

Then the total state of the gas should be either symmetrical in all the particles (boson gas), or anti-symmetrical (fermion gas). In short, the particles are entangled, not independent. So, we can't represent the state of the gas as a product of the states of the individual particles.

A first problem is how do we define the entropy of this gas?

The simplest expression for the entropy is,

S = -kB Σj pj ln pj

where kB is the Boltzmann constant, pj is the probability that the system is in the j-th microstate, and the summation is carried over all the possible (orthonormal) microstates ψj of the system. So, if the gas is in the beginning of its evolution in some mixture of states, pj is the probability of the state ψj in this mixture.

However, as the container is completely isolating, the gas is a completely isolated system and it evolves unitarily. The number of states remains the same all the time. So how can the entropy increase?

Also, sometimes in discussing the paradox, people speak of reversing the evolution of the system by reversing the velocities of all the particles. But the particles are indistinguishable, s.t. under the quantum regime they loose individuality. Moreover, the indetermination in the particles' positions is as big as the dimensions of all the container. So, where is the particle whose velocity we want to reverse?

So, bottom line, how we formulate the paradox in the quantum regime?

Sofia D. Wechsler · Technion - Israel Institute of Technology

Dear Eugene,

I am not sure whether I understood you. Why shouldn't exist a wave-function for an isolated system? Well, it may be a mixture of wave-functions, but an isolated system is supposed to have a Hamiltonian Ĥ, and the Hamiltonian to have solutions. Even if there is a gravitational field, which is known as conservative, still a Hamiltonian should exist.

The fact that the wave-packet spreads is well-understood. The evolution of a quantum state which is the solution of a Hamiltonian is given by

(1) ψt = exp(iĤt/ħ) ψ0

where ψ0 is the solution at some time that we take as t=0.  For instance, if Ĥ is the free particle Hamiltonian, i.e. no field of forces, one can expand the wave-function as

(2) ∫F(p1,...pN) Πj exp[i(pjxj - pj2t/2mj)/ħ] Πj dpj ,

where F(p1,...pN) is the Fourier transform of ψ0. The expansion (2) encapsulates the spreading that you say.

Unfortunately, in Loschmidt's problem the Hamiltonian is not of free particles, because a) there are collisions, b) there is a gravitational field. Agostino is right, the problem is not simply tractable mathematically, but in principle a Hamiltonian should exist, the difficulties are of technical order - computing power.

Best regards

• Which of the following Semantic Similarity criteria is bests(Please introduce 3)?

Semantic Similarity criteria based on Wordnet:

1- lin

Math equation is modified a little bit from Jiang and Conrath: 2 * IC(lcs) / (IC(synset1) + IC(synset2)). Where IC(x) is the information content of x. One can observe, then, that the relatedness value will be greater-than or equal-to zero and less-than or equal-to one.

2-RES

Resnik defined the similarity between two synsets to be the information content of their lowest super-ordinate (most specific common subsumer)

3-LCH

This measure relies on the length of the shortest path between two synsets for their measure of similarity. They limit their attention to IS-A links and scale the path length by the overall depth D of the taxonomy

4-Path

5-WUP

The Wu & Palmer measure calculates relatedness by considering the depths of the two synsets in the WordNet taxonomies, along with the depth of the LCS

• Alese Wooditch asked a question in Netlogo:
How can I calculate local moran's I in Netlogo?

I am interested in computing local moran's I in Netlogo to identidy hotspots. While I am able to export my data into another software to compute this, there is no software I am aware of to compute moran's I that will take into account the world wrapping.

How can i do Mann-Kendall test in MATLAB or other software?

I am going to study the chemical quality of water in a river for twenty years.

Is there any rule for attaching DNA stretches at both sides of Restriction site when designing a cloning primer?

Is there any rule for attaching DNA stretches at both sides of Restriction site when designing a cloning primer?

I only know 'neb' has protocol (https://www.neb.com/~/media/NebUs/Files/Chart%20image/cleavage_olignucleotides_old.pdf). But problem is here, two flanking stretches are most of the time complementary to each other and hence they form hairpin and strong secondary structure. Addgene suggests to add any 6 bases (https://www.addgene.org/plasmid-protocols/PCR-cloning/).

Is there any other rule?

Sincerely,

Bankim

Bankim Mondal · Bose Institute

Dear all,

But my question was, may I add any set of 6 bases of my wish at 5' end of Restriction site? This neb site (https://www.neb.com/~/media/NebUs/Files/Chart%20image/

cleavage_olignucleotides_old.pdf) is saying that only some sets of 3-6 bases at 5' end will enhance restriction digestion, not the all possible sets. Please see the case of restriction enzyme PvuI, SpeI etc of the chart can be seen fron attaches web-link.

Sincerely,

Bankim Mondal

Cultivating HUVEC and Endothelial tube formation assay
I have two issues I need help with:

1. My HUVEC cells in culture grow extremely slowly. I use a medium for culture of human large vessel endothelial cells with growth supplements added to it and 10% FCS and it still takes the cells 4 days to get to 80% confluency if I split them 1:2

2. I keep getting high background formation of endothelial tubes in my experiments control wells using low growth factor Matrigel and medium without any growth factors added to it and only 2% FCS. Has anyone got any ideas to why this is happening and how to reduce the tube formations?
Vahid Siavashi · University of Tehran

hi maria

we use EGM-2 for tube formation HUVEC

with 2% fbs for 6 -48 h

What is the most popular Linux distributions?

Linux distributions

How we improve the glass transition temperature of PLA polymer?

how we improve the glass transition temperature of PLA polymer?

Dear Ramachandran

I think this papers is good for u:

• What are the most recent versions of The Schwarz Lemma at the Boundary?

See for example   the paper arXiv:1001.1805v1 [math.CV] 12 Jan 2010,
The Schwarz Lemma at the
Boundary by Steven G. Krantz. In this paper the author explores versions of the Schwarz lemma
at a boundary point of a domain (not just the disc). Estimates on
derivatives of the function, and other types of estimates as well, are considered.The author reviews recent results of several authors, and present some new theorems as well

It seems that  this question is related to  Q1. Is there a version of Jack's lemma for hyperbolic domains in space?.

Miodrag Mateljević · University of Belgrade

One can prove for example

\begin{thm}
Suppose that $G$ is bounded connected open subset of complex
Banach space and $f: G \rightarrow G_*$ is holomorphic, $G_* \subset G$, $s_0= dist(G_*,G^c)$, $d_0=diam(G)$ and $q_0= \frac{d_0}{d_0+s_0}$. Then $k_{G_*}(fz,fz_1)\leq q_0 k_{G_*}(z,z_1)$ for $z,z_1 \in G_*$.
\end{thm}

Hence we have

\begin{thm}
Let $D \subset C^n$ domain for which Carth\'{e}odory
pseudo-distance is distance and $f : D\rightarrow D$ holomorphic
mapping such that $\overline{f(D)}$ is a compact subset of $D$.
Then $f$ is contraction with respect to Carth\'{e}odory metric on
$D$. In particular $f$ has fixed points in $D$.
\end{thm}

Can we have further application?

Can anyone help me in identifying this moth based on photographs?

Can anyone help me in identifying this moth based on photographs?

Harpal Randhawa · Punjab Agricultural University

It may be topi insect of fruit crops

I would like download JDK 1.6 for OMNET++. How can I install JDK 1.6 under OMNET++? Can get help?

Israa Albarazanchi · VIT University

thnx  ALIREZA

my system windows 7  32bit

regards

Which is the penetration depth of titanium dioxide nanoparticulated at 532 nm?

I need to know the penetration depth of anatase thin film when it is irradiated with a 532nm laser for a Raman spectrum.

Thanks

Jiwen Guan · The University of Western Ontario

I also wanna know how to calculate this. Juan, did you find a solution ?

Is there a relation of equivalence between energy and force (like mass energy equivalence) in the nature of physics?

In modern physics the terms mass and energy are often used synonymously. And force changes particle's kinetic energy. Also in thermodynamics, a force can change the internal energy of a system. In the context of GR, gravitational force arises as an effect of the curvature of spacetime caused by the presence of energy/mass.

Are the forces (according to quantum mechanics bosons) and energy are converted into each other? If the relationship between force and energy were discussed with a different perspective, we can achieve remarkable results.

Dear Kwei
I appreciate of your humbly, you are a honest scientist. I am glad know you.
Let me be honest, I do not know what a theory of everything is or human is able find a theory that it be able explain everything. As I said before, let's take a new look at relativistic Newton's second law. I have done it; maybe it will be interesting for everybody.

With Best Regards

What are the interesting classes of continuous functions from 2-sphere S^2 to itself?

One of the interesting classes  is class of quotients of complex polynomials. Is this class dense in C(S^2, S^2) in compact open topology?

Miodrag Mateljević · University of Belgrade

Rogier Brussee  is right:

the meromorphic functions are not dense in the continuous functions C^0(S^2, S^2),. This is because the degree of a meromorphic function (i.e a holomorphic map CP^1 to CP^1) is non negative. But as I said before  the set of rational functions  R(S^2, S^2)  on $S^2$ is closed  with respect to spherical metric.  Of course there is  a continuous function in  C^0(S^2, S^2)  which is not rational and there fThe meromorphic functions are not dense in the continuous functions . Perhaps  an iteresting question is:

whether  every homeomorphisam can be aproximated by quasiconformal mappings on $S^2$.

Is there anyone working with X-Ray CT Skyscan 1172?
I am working with X-ray CT Skyscan 1172 and its accompanied software CT-An. Are you experienced with this device? Can we share some analysing techniques, especially in diffusion mapping and porosity analysis.
H. Douglas Morris · National Institutes of Health

Nicolas,

You can contact the company at http://www.skyscan.be/ and ask where the nearest university that they have a scanner installed.  Generally, the SkyScan company is quite helpful in finding resources for new users.

Sincerely,

Doug Morris

• Jobin Thomas asked a question in Landsat:
How can we derive the vegetation indices for Landsat 8 data?

Since Landsat 8 has different spectral widths, how the equations to derive various indices (e.g., NDVI) are to be modified ?

Why early life stage of fishes are more sensitive to toxicants?

Variations in sensitivity between life stages have been reported for aquatic organisms. Early life stages of fish and invertebrates have been shown to be more sensitive to toxicants than the adult organisms. Although this phenomenon can be explained on the basis of difference in surface area/volume ratio, toxicant uptake, underdeveloped organs. However, is there any molecular basis for this difference?

Kamran Shekh · University of Saskatchewan

I have searched for this including the references provided by Saeideh and I found several statements like the one you added. However, most of them are only speculative in nature with no molecular support. However, I may find something if I search thoroughly.