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- What programs can draw good phase diagrams for 2-dimensional (or 3D for that matter) systems of differential equations? What do the results look like?
Presumably, a good diagram would include nullclines, arrows, the stable manifold in a 2D saddle point system, etc.
I've recently found a software called "TRUE" which is a tool for modeling, simulating, analyzing and creating 2D (3D) systems. Here is the link: http://www.true-world.com/htm/en/index.htmlFollowing
- Are you interested in collaborating on work in integrated agricultural systems to protect the environment?
For the EU Horizon 2020, is there somebody interesting in applying with me to this call under the title:
" Integrated agriculture system to protect environment "
The Deadline for submission for RISE is: 28 April 2015
Also the following link will help you to get more information about the submission process:
Dear Mr. N Mustafa,
I am Dr. Md. Belal Hossain, working as Associate Professor in the Department of plant Pathology , Sher-e-Bangla Agricultural University, Dhaka, Bangladesh. Yes I am interested to your proposal. Please write me detail how we can submit the project in collaboratively?
Thanks for your kind attention.Following
- Can the Shannon-Weiner species diversity index be a good monitoring tool for assessment of health of any type of ecosystem?
Diversity indicates the condition of an ecosystem.
I agree with Onildo Marini-Filho, but its important to use them altogether to reflect the ecological status.Following
- Which software do you think is better to register and analyze rodent behavioral task?
We are looking for buying a software to analyze different kinds of behavioral task in mice and rats. Up to now, we have used ethovision, but we have heard about any-maze as an another choice. It looks to me more intuitive than ethovision, but I have never used it, so I would like to know the opinion about how functional it is. I will be grateful for your help.
The Stoelting ANY-mazeFollowing
- There is a peak in my XRD of MWCNT at 39.3135 degree. What possibly could that be? Platinum catalyst or any other impurity?
I know that the peak at 26 degrees corresponds to Carbon...but the peak at 39.315 degrees is a bit more intense and i was hoping that it could be only platinum catalyst impurity and not any other impurity.
Thank you Mr. Siba Soren and Mr. AdayemiFollowing
- How to group different insect orders into several groups?
My research topic is to explore the biogeograpgic patterns of species richness of insects. I have the regional richness data of all insects and different orders from many locations. It's well known that insects include c. 30 orders with different number of species and phylogenies. I want to group different insect orders into several groups, and make a clear description of their diversity patterns. The problem is "How to group different insect orders into several groups?".
I'm also looking for someone interested in this project. Please contact me if you want to join me.Following
- Does timing of the blood sample collection from rats without any fasting schedule affect blood parameters excessively and create huge differences?
I tested some blood serum parameters like HDL, LDL, trigyceride etc. and leptin in albino wistar rats. When I look at the literature I could not any direct answer about right timing of blood collection. If I applied sample collection in the same way, same time, same row for all animals, can eating of rats before blood collection still create a huge induvidual variance differences and avoid to have significant data for treatment? Please help me, I am completely confused...
Dear Ozlem, yes of course, in my experience, if you do not consider fasting for the animal, you will have big difference in blood biochemical and hormonal results. The animal may have different weight, different appetite, different eating time and so on. So if you measure feeding affecting analytes e.g. Glucose, Triglyceride, ....you will obtain a very different result in comparison to fasting state. For measuring lipid soluble analytes, e.g. determination thyroxine (T4), Tse (testosterone),...these analytes prefer chylomicrons as solvent and leave water phase to lipid phase, and you will encounter to false negative results. Finally in some exception you can blood collection without fasting but generally it is recommended blood sampling in fasting sate (without food and free access to water).
- Who has got more power: the Gray eminence or the Head?
Throughout history there have been many high-profile cases of personalities behind the scenes directing power with or without the consent of the person who would have had the charge to exercise it.
In ancient Rome: Seneca and Nero
In France: Richelieu / Mazzarino versus their king
In the US: Eleanor Roosevelt versus Franklin Delano Roosevelt
In every day's life:
wife versus husband
secretary versus head of the department
assistant professor versus Professor
And in your life would you prefer to act as a gray eminence or as a head?
This strikes me as an interesting question, but more because it brings to light questions concerning styles of leadership and politics. We naturally assume that people can simply be themselves and say what they think. But we have all perhaps sometimes encountered versions of one thing hiding behind another, or one person hiding behind another.
My sense of the phenomenon of one person hiding behind another is that it is a sign of a rather byzantine style of politics, and nothing very positive. When politics and matters of appearance get that complicated, it is likely better to do some reorganizing --breaking down overly complicated situations or organizations. Similarly, "representatives" may hide, one behind the other. You get someone of character xyz to represent the interests of abc, because the xyz folks are not likely to be accused of blind prejudice in favor of abc, as the abc folks might be. This again, I take to be a kind of byzantine politics, meaning by that something overly sophisticated, excessively complicated and perhaps even directly deceptive.
I take it there are degrees and variations on similar configurations. Sometimes they can be bothersome, even destructive; at other times or in other variations, they can be pretty innocuous --at least for those who have some familiarity and who have learned to deal with similar situations. Certainly, I'd rather be Seneca than Nero, but neither role really appeals to me.
I'd rather be Socrates, but then, again, I don't do philosophy on the market square.
Amor fate. To thine own self be true.
- Can an electron transport chain function without a functional ATP synthase?
In the case with non functional ATP synthase maybe proton influx will be affected but still oxygen can receive electrons to form ROS.
In uncoupled mitochondria, when the electrons leak produces heat. As in the brown fat of animals that hibernate (UCP protein). Or mitochondria treatrd with FCCP.Following
- How PEG 4000 polymer film formed easily ?
UP on your suggestions, when I placed PEG 4000 polymer solution which casted on glass petri dish and kept in hot air oven AT 60 C , for 24 Hrs. although i am not getting proper film, and film is wet and uneven too. plse suggest me how to solve it.Following
- What are the indirect disadvantages of using Solar Energy Technology?
Normally Solar energy is Eco-friendly, how ever the ingredients required to prepare the process of solar collection is complicated and requires different forms of raw materials or processed materials. Is there any known hazard or disadvantages of such products?
Lot of Thanks to all of you who have helped me get a better understanding on the subject.Following
- Different results using alternative approaches in a long run cointegration relationship?
I have found that there is cointegration between logY logX1 LogX2 using Johansen.
1. If I continue with a FMOLS regression, what is the criterion for choosing constant or linear trend? The results are very different.
2. If I continue with an ARDL (Microfit) I find different results from Eviews. While X1 is statistically significant using Eviews FMOLS it's not significant using ARDL. Could anyone help me about this strange result?
Thanks in advance.
FMOLS: OLS is considered biased estimator when there are cointegrations. FMOLS fixes this problem. For instance, in time series, when there is shock to the system, i.e. significantly large and erupt change in the underlying X to throw Y out of its long-run equilibrium, OLS would not be able to give a good estimate. The issue becomes even more complicated when the effect of the shock is integrates (absorbed) into the series and the system does not go back to its long-run equilibrium (non-mean reverting effect). FMOLS improves the forecast in this situation. This explains why you find "no significance" under FMOLS and significant under ARDL. Try introduce ECM to your ARDL and compare the result again.
DE-TREND BY ARDL: ARDL moel de-trend the series in order to affect stationarity. What if the series integrated the sock? and the shock is just a single or short burst not enough to be a trend but the effect of the shock is integrated, i.e. causing regime change? ARDL would have dicculty handling this issue with introducing error correction mechanism.
ERROR CORRECTION MECHANISM: ARDL model may be reparametize by introducing error correction mechanism. If ECM is introduced, you might see consistent result between ARDL and FMOL. Recall that FMOLS is two step ahead: modified OLS and then "fully modified" OLS. The modification serves as an error correction mechanism in FMOLS.
REFERENCES: See links below. For various approaches in econometrics in different theoreticl and methodological approach see: http://en.wikipedia.org/wiki/Methodology_of_econometricsFollowing
- Is there is a relation between Coma aberration and Tilt aberration?
I want understand does tilt aberration cause (or may cause) the Coma aberration under certain conditions. Thank you in advance!
Hans Buchdahl developed an extensive theory of geometrical aberration coefficients in which he addressed not only first order coma but also higher orders (Optical Aberration Coefficients, Dover Publications 1968). He distinguishes between aberrations depending only on the angle of the object away from the axis of symmetry of the optical system (e.g. tilt or distortion) and terms depending on odd orders of that angle but also having an aperture dependence (various orders or types of coma). Clearly , then, tilt and coma have different dependencies. They are not necessarily orthogonal (since both depend on the position in the field of view, but coma has an aperture dependence that tilt does not. If one chooses only to consider first (or Seidel) aberrations then distortion (or tilt) has no aperture dependence but a cubic dependence on tilt, whereas coma has a linear dependence on tilt and quadratic dependence on aperture (for image plane - lateral - measures of aberration rather than wavefront measures of aberration). Happy to discuss further if you're interested.Following
- In case the of acute facial nerve palsy, what is better: laser or stimulation?
Does muscle activity improve by either laser or stimulation?
- How can I stimulate muscle cell contraction in vitro?
I want to mimic exercise conditions in vitro.
Caffeine mobilizes Ca+2. Concentrations are described in the literature.Following
- Is it possible to assemble perovskite solar cell without using vacuum depositing?
The counter electrode is prepared by vacuum deposition of gold and is there any alternative method available instead of that.
Thank you all. :) I will give a try.Following
- Between the rotenone and MPTP/probenecid models, which one is the more progressive model of PD?
I have received excellent contributions on the choice of the PD model in mice to employ in my project. Please, of rotenone and MPTP/probenecid models, which one of the two will produce a relatively more progressive degeneration?
I understand that treatment is systemic because Probenecid. In this case, MPTP is good for C57BL6 mice. Rotetone for rats.Following
- What are the ways to avoid and dodge plagiarism in scientific writing?
It’s easy to find information for most research papers, but it’s not always easy to add that information into your paper without falling into the plagiarism trap. Kindly give tips to avoid plagiarism.Following
- Can someone point me to cases of governments ceasing to exist?
I am seeking cases where a US government of any kind (special purpose entity, school district, township, airport authority...) ceases to exist. I am referring to the entire apparatus of government, not just the case where one administration or political party replaces another. The termination could be from bankruptcy, annexation, end of its special purpose, etc. The goal of the research is to understand the distribution of that former government's assets.
In Elliott Freidson's 1985 article, "Reorganization of the Medical Profession" he quotes Roederer and Palmer (1981, 2) stating that "various states have passed "sunset laws" which automatically terminate "a board, commission or agency unless reauthorized or reestablished by the legislature". It would be curious to note whether said laws are still in existence and to what extent they have played a role in the dissolution of these particular government apparatuses.Following
- Does anyone know if a threshold model fits better than a linear model when running an animal model with binomial variable response?
Does anyone know if a threshold model fits better than a linear model when running an animal model with binomial variable response?
Please provide more specific information.
Is the binomial response "captured versus not-captured" "tagged versus not-tagged" "infected versus healthy" "dead versus alive" or something else? What are your variables? What was your sample size? What are the goals? The more you tell us the more we can help. Or is this a simulation model that you are running and you are trying to predict the outcome? Why not run both models and see which one fits better? That is probably the best approach. Then figure out why you got this answer, and in this effort you will gain a much better understanding of how the models work with your data. Try other models, try other programs. The different analysis programs are not all equally good for all possible data sets.Following
- Should the law enforce conventional morality?
What is conventional morality? What is the consequence for the enforcement of conventional morality? Could anyone provide the case studies about it, thank you in advance.Following
- What test would I use to compare gender and age group, which are small under 32 and unequal, in HRQoL scores? Would I use Chi-square or two way ANOVA?
I would like to know what the differences are between male and female and age group in Health-related quality of life scores. The comparisons would be male children and male adolescents; female children and female adolescents, males and females, and children and adolescents in each of the HRQoL dimension scores (10 dimensions). My sample size is 32; unequal numbers between both gender and age-group.
Consider a dimension reducing multivariate technique. Something like Discriminant analysis where you can get a Mahalanobis distance between your groups. You can then use the Mahalanobis distances with a Mantel's test to decide if all the groups are equidistant of if some are significant further away from others. The statistical analysis package should take care of unequal sample sizes.
So you have:
1) male child versus male adolescent
2) female child versus female adolescent
3) male versus female
4) child versus adolescent
There are 4 categories, with a total of 32 responses unequally distributed. I guess one problem is how unequal? If one category has a single individual then you will have problems. The outcome for each of the 4 comparisons will not be independent. So if there is a significant difference in #1 there is more likely a significant difference in #4. By making this a single multivariate analysis you will take care of this little problem. I would guess that your 10 dimensions are not all independent from one another, and this approach will help with that problem too -- either going through a stepwise selection process or by calculating variables that are linear combinations of the ten dimensions. The big problem here will be if some of the data is missing.
I also agree with Elmer, it would be really good to get your sample size up. However, there could be some factor that was not made clear .... such as this was for children with some rare medical condition.Following
- What is the difference between the G and the RPM in Centrifugae Machine? Is it same or what? Does it have any specific formula for conversion? While reading a paper I came across 10000 X G. Can some one help me to understand the meaning of it, as I do not know what it means? Is it different from RPM? While I was going through the paper only 10000 X G was mentioned, there was no RPM. So what does this mean?
Can anybody give some reference for citation for the equations that are discussed here? Is those websites can be cited for a journal article? Or I need to cite a published journal article or book? If any body has the name of the book please provide that also. Thank you.Following
- What are the methods to create a plasma in the chamber for the thin film deposition ?
What are the methods to create a plasma in the chamber for the thin film deposition ?
Why chemical vapor deposition of heavy metals is the problem?Following
- Can anyone help troubleshoot LNCaP cell unresponsiveness to Ca2+ agonists?
I am attempting to measure the store-operated calcium entry (SOCE) response of LNCaP cells when stressed with Thapsigargin. I'm using Fluo-4 AM as my indicator dye*. The cells are not responding for a range of concentrations (1-4 micromolar), and, more importantly, are not responding to my Ionomycin controls**.
At first, I suspected that the deesterification process was not complete, so I left the cells at RT for 30 min before continuing experimentation, but no dice. Superperfusing the cells does not work (2mL/min flow rate in a 1mL volume chamber. 5 min sustained exposure to agonist), I've also tried static incubation and the cells are still unresponsive. The cells do not even appear to be blebbing substantially after sustained (>10min) exposure to Ionomycin.
I'm planning to perform a plate reader assay testing Fluo-4 with Ca2+ in free solution, but it was purchased quite recently, so I doubt that is the issue.
I can't think of anything else other than I somehow failed to get thapsigargin and ionomycin into solution when making my aliquots. There are various papers show that LNCaPs are responsive at the molarities I'm using, there is no evidence of excessive or rapid compartmentalization. Does anyone have ideas, or other controls I could try? Or perhaps tips when making up agonist solutions, if that is the most likely area for concern. Thanks!
*Protocol: incubating the cells at 37C with 2 micromolar Fluo-4 in 2mM Ca2+ HBSS solution for 30min, then rinsing twice with Ca2+ free HBSS
** Min: 5 micromolar Ionomycin and 10mM EGTA in Ca2+-free HBSS. Max: 5 micromolar Ionomycin in 10mM Ca2+ HBSSFollowing
- Will recent warming hiatus with respect to mean temperature continue or not?
2014 became the warmest year on record, without a strong El Niño. The so-called global warming hiatus (1998-2012) are widely concerned. In the following decade, global mean temperature warming will continue to slow down, or will rise much more rapidly than in the "slowdown" period? What are main physical causes responsible for inter-decadal changes of mean temperature?
Harry ten Brink
Query: Where is your percentage coming from?
Please see this URL:
http://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter06_FINAL.pdf (accessed Nov. 12, 2014, Feb. 01, 2015)
Figure 6.1. Simplified schematic of the global carbon cycle. Numbers represent reservoir mass, also called ‘carbon stocks’ in PgC (1 PgC = 1015 gC) and annual carbon exchange fluxes (in PgC yr–1). Black numbers and arrows indicate reservoir mass and exchange fluxes estimated for the time prior to the Industrial Era, about 1750 (see Section 188.8.131.52 for references). Fossil fuel reserves are from GEA (2006) and are consistent with numbers used by IPCC WGIII for future scenarios. The sediment storage is a sum of 150 PgC of the organic carbon in the mixed layer (Emerson and Hedges, 1988) and 1600 PgC of the deep-sea CaCO3 sediments available to neutralize fossil fuel CO2 (Archer et al., 1998). Red arrows and numbers indicate annual ‘anthropogenic’ fluxes averaged over the 2000–2009 time period. These fluxes are a perturbation of the carbon cycle during Industrial Era post 1750. These fluxes (red arrows) are: Fossil fuel and cement emissions of CO2 (Section 6.3.1), Net land use change (Section 6.3.2), and the …………..Following