ResearchGate Q&A lets scientists and researchers exchange questions and answers relating to their research expertise, including areas such as techniques and methodologies.
Browse by research topic to find out what others in your field are discussing.
Is there any model for management of Diabetes for poor diabetics having components of medical ,nutritional and life style interventions?
A lot of poor and uneducated diabetics are unable to manage their disease. They fall into the vicious cycle of hyperglycemia and hypoglycemic events.Following
Can I use α-MEM with phenol red but without HEPES to grow mesenchymal stem cells?
I am going to cultivate MSC and I have some doubts related to buy reagents. Please, may someone help me?
Minimum Essential Medium (MEM) α is widely used for mammalian cell culture as well as selection for transfected DHFR negative cells. MEM α can be used with a variety of suspension and adherent mammalian cells, including keratinocytes, primary rat astrocytes, and human melanoma cells. Life Technologies offers a variety of Gibco® MEM α modifications for a range of cell culture applications.Following
What is about the term topobiology by definition and its significances in life and biomedical sciences?
Originally, the term topology is from mathematics. Now topobiology is applied to life and biomedical sciences, largely because most of biological events, cues and/or molecules could not be defined by both quantity and quality, but they are enabled to be dictated by spatial positioning and conformation patterning?
Thanks. Changes in structural conformation of biological molecules and complexes should be included in a subarea of topobiology.Following
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.
LT doesn't reverse the direction of time's "arrow" − doesn't interchange cause and effect.
It does, however, tell us that what is in the future for an observer may be in the past for another observer! My "now" (at time t0) consists of all events that happen at the same time t0. But I cannot "now" observe any of those events.
I agree with the first paragraph for two reasons
a.It is clear mathematically the time sequence of events is conserved after LT
b There is no time arrow so there is nothing to reverse, but if it is only a metaphor for the sequence of events it is fine
The second paragraph I cannot agree with without reservations.
Lorentz transformation maps one point from one coordinate system to another so it does not add any new information. Trajectories defined by equations of motion as a function of scalar parameter t representing time tell everything about the future and the past in the stationary system with two exceptions:
a. Initial condition
The two exceptions lie outside the control of algebra and have to be defined by physical reality constraints.
No trajectory equations are true if they describe a motion before the moving body came to existence, and no trajectory equations are true if they describe a moving body after it has ceased to exist. This happens if the initial position of the motion is shifted away from where it really originates. And this is quite common after LT.
I have shown this is quite possible to describe non-existing positions of a non- existing body being simultaneous with the existing one after LT.
The apparent past future thing is of a similar nature as in the following example that does not involve relativity but some signal transport delay
Imagine a large cruise ship drifting parallel to the terminal simultaneously touching two tyres absorbing the shock which are mounted in front of the opposite ends of the ship. For an observer on the edge of the embankment at some distance away from the ship, the closer of the two simultaneous event comes earlier than the other, from which he may incorrectly assume the ship was not parallel to the embankment.
This kind of effect in LT is not caused by transport delay but a particular clock synchronisation which is oblivious to simultaneity of events because its purpose is to keep the speed of light constant.Following
Is my buffer preparation for circular dichroism experiments correct?
We are recording the CD data using 2 mm quartz cuvette for measuring the CD in Jasco 815 CD spectrophotometer. I need data upto 180 nm in order to calculate secondary structural features. Unfortunately the HT voltage increases more than 500 KV while setting the blank (0.05 M KH2PO4 pH 7.4 without any filteration and degassing) itself below 200 nm. To overcome this problem we planned to use 0.01 M phosphate buffer pH 7.4 for our protein to measure CD data. I use milli-Q water for buffer preparation after filtering through 0.2 micron filter. Is that advisable to filter the buffer again through the filter... will it make change in pH if i do so? Then what would be a better method to degas the buffer without altering the pH. If I use this method and prepare buffer will it be possible to collect data below 200 nm (upto 180 nm) ?
Note: The protein sample will be also prepared by filtering it through a 0.2 micron syringe filter and dialyse it against the above prepared buffer and will be used for the sample data. Ultimate requirement is data from 600 nm to 180 nm... can anyone suggest how to meet above the requirement efficiently?
Thats very very informative Berndt. Let me make note of all your points and workout.... Let me obtain the spectrum. If I have any further clarifications will sure ask you. Thank you so much for your detailed explanationFollowing
There is a relationship between measurement model and path model in AMOS analysis. Which model picture is essential for final Ph.D. Thesis Report?
There is a relationship between measurement model and path model in AMOS analysis.Following
No experiment directly observed Quark particle, why do we think Standard Model is a valid theory?
The Standard Model of particle physics is a theory concerning electromagnetic, weak, and strong nuclear interactions, which mediate the dynamics of known subatomic particles. The current formulation was finalized based on the existence of quarks. There is no way to proof the existence of quark. It is pretty risky to build a theory one something that may not exist. It neither explains force hierarchy nor predicts the structure of the universe. The Standard Model falls short of being a complete theory of fundamental fields. Mathematically, the standard model is a quantized Yang-Mills theory. Because of its success in explaining a wide variety of experimental results, the Standard Model is sometimes regarded as a "theory of almost everything".
There is a review by A.S. Kronfeld in Annu. Rev. Nucl. Part. Sci. 62, 265–284, (2012). doi: 10.1146/ annurev-nucl-102711-094942, with title Twenty-first century lattice gauge theory: Results from the QCD Lagrangian. Low-energy QCD is probably the quantitatively most challenging part of the Standard Model, but also here the results starts to look quite impressive.Following
How can I use plasma treatment for surface modification?
In plasma treatment,we should use a powder for covering the surface?or only making H pattern and free radicals is enough?
I want to use this method for surface modification of scaffold.
thanks for the linksFollowing
What is the governing physics of microparticle generation? How is the size obtained and controlled? What are the parameters affecting the size?
What parameters affect the microparticle size and how are those parameters linked? I need the governing physics on the microparticle generation but focusing on the particle size control.
Your question is very broad , but in general:
You refer to microparticles, not to nano.
Of course the governing physics will depend on the method you use for preparing them.
Also it will depend on the material, it is not the same to prepare micropart from a ceramic brittle material than from a metal that can exhibit plastic deformation.
Depending on what you prepare you can have agglomeration because of electrostatic charges.
If the gaseous atmosphere has molecules that can be adsorbed on the particles surface ( water for example) it can affect the interparticle interactions.
Is there any evidence to support the finding of P values in descriptive studies?
A lot of studies are seen where researchers declares study design as descriptive cross sectional but also finds out p values with various factors in the study. Whether any evidence supports this practice as theoretically p values means testing of hypothesis which cannot be done on descriptive study.
Thanks Professor Muayyad Ahmad. so a person who is doing only description of a group and then tries to fine out association of various factors with variable of interest, should either call his study as mix design of cross sectional descriptive and analytical, is any such design be made
he should report association found but not to mention p values and say significance cannot be reported due to being descriptive and further research is req to explore.Following
What is the permissible Consistency Ratio for the Analytic Hierarchy Process (AHP) instrument?
Can anyone familiar with the Analytic Hierarchy Process (AHP) instrument discuss on the permissible limit of the Consistency Ratio (CR). Although T. L. Saaty allows a limit of not more than 0.1, there are authors who allow the CR untul 0.2. Will it be okay to use the 0.2 CR limit? Thank you.
Dear ALL. Thank you very much for your comments and recommending the relevant articles. They have been helpful in developing my understanding on the use of CR beyond 0.1 until 0.2. From my own experience from conducting interviews and surveys with maritime experts, it was not easy to persuade them to agree with a pairwise comparison that would come to a CR of 0.1 and below. For them, things are not as straight forward as a simple comparison such as when A is 3x better than B, and B is 3x better than C, than A should be 6x better than C. I also believe a CR of 0.2 would be more practicable in allowing for some flexibility for the respondents to express their judgments without the worry of getting their judgments rejected because of non-conformance with the 0.1 CR requirement. Thank you once again.Following
Is it worth publishing with Lambert Academic publishers?
My inbox has repeatedly been spammed from lambert Academic publishers. Is it worth publishing with this publisher. Do they have any authenticity. There is a lot of bad stuff written about this. Still, people publish their thesis with them. How one could publish your results in the form of book when its already published in the form of research articles. Are they peer reviewed....Suggestions welcome
They are sending emails to every person...Following
Can anyone suggest some journal for publishing cell culture work?
cell culture work has to be published kindly suggest some journals
I couldn't download the file please upload it againFollowing
Any research on reusing lab rats for multiple studies?
I'm investigating what happens to lab rats after an experiment is complete. I've heard that in some behavioral studies, rats are allowed to live to complete another study in the future, whereas for physiological studies they are usually killed.
Anyone know any research on whether the same subjects can be used for multiple experiments?
If you search the Subjects section of the Journal of the Experimental Analysis of Behavior, The Psychological Record, or Behavioural Processes , you will frequently encounter language along the lines of "rats had previous lever-pressing experience." This indicates they were used in multiple studies. If rats are used for studies on learning and memory that do not involve invasive procedures (for example a lesion), they can certainly be used in several investigations. Their relatively short lifespan can be a limiting factor compared to pigeons or nonhuman primates.Following
How do I measure xylose concentration without using HPLC?
is there any method to quantify the concentration of xylose (xylose only, not in mixture form) other than using HPLC. for example, detection by using any assay, o uv-vis maybe?
Thank you so much for the answers.. it do help me lot...Following
Can I use a logistical regression for this type of problem?
I want to test whether better off people are more likely to receive a specific good (=good X) than less well off people. Thus, my independent variable (wealth, measured in US$) is continuous. My independent variable (did they receive good X: yes/no) is dichtomous.
Is the logisitical regression the best test for this?
And if so, do I interpret the results correctly? I interprete them as follows:
Prob > chi2 = 0.0001: thus, one of my variables (or in my case, my one and only variable) does contribute to explaining the dependent variable.
P>|z|=0.000: thus, wealth does contribute to explaining the likelihood of benefitting (or not)
HOWEVER: Pseudo R2 = 0.0091: thus, my model fits very poorly, and I have left out lots and lots of other explanatory variables
And also, running a "fitstat" on Stata resulted in an Adj Count R2: -0.004. Thus, using the independent variable wealth only leads to a 0,4% improved prediction of whether people receive good X than not attempting to explain anything using the variable wealth.
Thus, if all of the assumptions of a logistic regression are met, in conclusion, one can say that a person's wealth does NOT have an influence on whether or not they will receive good X. Is this right?!??
And second question: is there a better test I could use for this?
Thanks so much for any help!!
perhaps you can find this post useful.Following
Complimentary abstract editing for first time users?
For more details contact @ email@example.comFollowing
Can I make a nother PCR from the PCR product instead of genomic DNA?
as the genomic DNA is broked
If your downstream experiment is important (for example, gene expression), you need to make sure that the sequence of the PCR product derived from the genomic DNA is correct (no mutation). If you have mutation(s) in this PCR product, your subsequent PCR amplification will carry these mutations. Then, you will be in trouble. Have you sequenced the PCR product which you intend to use as template for second-round PCR?Following
Is there any Genius in solar physics ?
Recently, I have more and more realized a single fact that I cannot identify a Genius in solar physics.
Thank you very much for pointing out that. Indeed, it's a matter of recognition. (I added a link for Forbush)
>But then you are much more likely to get your result named after you if the idea is >already in people's minds because someone else got there first.Following
Can some one suggest me a good journal to publish my work on antioxidant and anti inflammatory activity of some medicinal plants?
my work includes applying DPPH and caregenan rat paw edema test to the plants
First, you should ask yourself if your result is novel. There are a lot of good journals that will gladly accept your manuscript if it is well prepared.and the result is novel.Following
Can somebody explain me importance of nanoparticles in dna vaccine adjuvant?
Lately, I am reading a lot of paper on dna vaccines topic and I cannot understand part that is refer to nanoparticles...gold, liposome, chitosan etc
How this particles can be considered as effective carrier and what are meaning of it?
thank you very much, I found it.
that resercher have a profile on RG
Could Faraday effect happen in vacuum?
Faraday effect is usually observed in medium. The light's polarization will change a little when it propagate in magnetic field. But what if there is no medium, just vacuum and magnetic field. Will the polarization of propagating light change then?Following
Why are lab rats euthanized rather than returned to "the wild" after the experiment?
Any thoughts? Why are lab rats or other subjects euthanized after an experiment is completed?
Rats that are used in scientific experiments are specially bred for this purpose-- they have never been in the wild, and if you were to "return" them they wouldn't have the skills to survive. Albino rats, the most common strains used in research, would be extremely easy targets for predators. It is far more humane to euthanize the animals with a quick and painless death, rather than dumping them into a frightening environment where they will quickly become food for another animal.
Any experimental manipulations performed on rats could very easily harm other wildlife if they were released. It would be very dangerous to release transgenic animals, animals that have been exposed to infectious diseases, or surgically modified animals into the environment.
And of course, euthanized rats are often still very useful in an experiment. If you want to look inside their brains, you've going to have to take it out of their head first.Following
Should I use cold or warm PBS washes when performing protein extraction?
I have read various protocols that use cold PBS when performing protein extractions. However, this strikes me as odd because I feel like cold PBS would shock my cells and cause their protein expression/signaling to be different. Is there any specific reason for why most protein extractions use cold PBS instead of warm PBS?Following
Rutting in asphalt is a 'stress controlled' phenomenon. Then why do we measure the rutting factor in a 'strain controlled' temperature sweep?
rutting factor- G*/ Sin δFollowing
Are you familiar with quantitative analysis of flavanoids in medicinal plants using HPLC and UV/VIS?
Can anyone help me with list of methods for quantitative analysis of flavanoids in medicinal plants using HPLC and UV/VIS?
You can isolate and purify flavonoids by using a mobile phase consisted of methanol-acetonitrile-water. (60:20:20 v/v/v). For this purpose a selective and sensitive reversed-phase (RP) high-performance liquid chromatographic method is developed for the quantitative analysis of five naturally occurring flavonoids from plant leaves. There are
so many flavonoids such as dihydroquercetin-7,4'-dimethyl ether (DQDE),
blumeatin (BL), quercetin (QN), 5,7,3',5'-tetrahydroxyflavanone (THFE), and dihydroquercetin-4'-methyl ether (DQME) were isolated by using this method.. These
compounds have been isolated using various chromatographic methods. The five compounds are completely separated within 35 min using an RP C18, Nucleosil column and with an isocratic methanol–0.5% phosphoric acid (50:50, v/v) mobile phase at the
flow rate of 0.9 mL/min. The separation of the compounds is monitored at 285 nm using UV detection. Identifications of specific flavonoids are made by comparing their retention times with those of the standards. Reproducibility of the method is good, with coefficients of variation of 1.48% for DQME, 2.25% for THFE,
2.31% for QN, 2.23% for DQDE, and 1.51% for BL. The average recoveries of pure flavonoids upon addition to lyophilized powder and subsequent extraction are 99.8% for DQME, 99.9% for THFE, 100.0% for BL, 100.6% for DQDE, and 97.4% for QN. After lyophilization, the leaves of the plant samples are ground using a Centrifugal Mill. A portion of the powdered samples (100 mg) can be extracted for 6 h with 10 mL of methanol in glass-stopped vessels on a hot plate with magnetic stirring at 40°C. After centrifugation at 3000 g for 10 min, the extracted sample should decanted and the remaining solid residue is extracted three times with 5 mL of methanol. The extract is evaporated in vacuum to dryness at 40°C. The solid residue is reconstituted with 5 mL of methanol and 20 µL was injected into the HPLC system.
Stock solutions of standard DQDE, BL, QN, THFE, and DQME (1 mg/mL) are prepared in methanol. Stock solutions are further diluted with methanol to prepare different concentrations of flavonoid standard solutions. All standard solutions were stored at
4°C before use. Detector linearity The detector linearity is assessed by injecting aliquots of the standard solutions in methanol: 0.025–100 µg/mL for DQDE and BL, 0.05–100 µg/mL for QN, and 0.01–100 µg/mL for THFE and DQME, respectively. The peak area versus the amount of the flavonoids injected is plotted to determine the linearityFollowing
Is there in use any outcome measure tool for use in evaluation and management of Erb's pasly or any other form of obstetric brachial plexus palsy?
Erb's neurological and musculo-skeletal injury
Highly informative Amitesh....
How to obtain the value for money in PPP and traditional infrastructure public procurement ?
what is the value for money in traditional infrastructure public procurement and the by comparing both PPP and the traditional procurement what method can we ascertain value for money in case of both.Following
What is Ideal solvent for isolating phenolic or flavanoid? can we use methanol and ethanol in combination?
Although hydro alcohalic solvent is ideal for maceration but i could not use water for certain reason can i use ethanol and methanol 1:1 in combination?
You should use methanol, because its extraction power is higher than ethanol.Following
What is the best strategy for dealing with bad bosses?
I advise coworkers and clients regarding career issues, how to deal with bad bosses, self-directed career planning, hard skill development and so forth. Usually the answers are linked to organizational behavior, because my goal is to assist with career advancement. I would like to draw upon the HR intelligence of RG. Please, let me know your thoughts.
The term BAD is a relative one. First thing we have to do understand our authorities. Be respectful and well behaved towards them. We generally feel bad against one person if he acts or speaks against our truths and thoughts. We may not appreciate a very strict boss.
I admit that there are bad people also. There may be some cases where the authorities have no idea about how to handle employees positively and to take good and effective strategies for the virtue of their firms. In such occasions, don't try to be a rebel and try to openly discuss things with them if possible.Following