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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- How can I get a list of all genes/enzymes involved in metabolism is human cells?
I am interested in checking whether genes involved in metabolism are regulated upon treating human cells with a certain drug. However, I cannot find a comprehensive list of these genes that encode metabolic enzymes. Any idea how I can get such a list?
- When the magnetic materials size is reduced to nanoscale ,the domain wall formation energy overcomes the domain energy, or vice versa?
Dear Greig and Bruno ,
please describe and explain the follow phrase:
((Small magnetic particles are typically monodomain, since the energy cost to form a domain wall outweighs the reduction in magnetic energy)).
- Can we correlate results from inflammatory response in RAW 264.7 cell lines and STZ induced diabetic neuropathy?
If a drug shows good anti inflammatory response in LPS induced inflammation in RAW 264.7 Cell lines and good hypoglycemic response in diabetic rats, does it work against diabetic neuropathy?
"Because hyperglycemia and inflammatory mediators are one of the major factors to develop diabetic neuropathic condition"
I consider diabetic neuropathy as a late event in human - I am not sure how this is diagnosed or monitored in the rat model; I also do not know how good mechanisms of mouse immune cells, especially macrophages, can be extrapolated to human organisms (there have been findings 20 years ago on mouse NO pathways in macrophages, which have been under critical discussion, since a friend pointed out that human macrophages may not have the same pathway - but in principle, most pathways exist in humans and one can investigate and perhaps confirm them); on the other hand, I would consider anything which can help regulate blood glucose to normal levels, as "preventing" either diabetic neuropathy or preventing its progression. Not sure if you can achieve a cure of neuropathic conditions.Following
- Where is it considered soil from the limit with a very weathered rock mass?
I want to know how to recognize soil from a very weathered rock mass.
You can divide the two materials by some approach. One is classification by grading of the grains. Soils have 4 categories such as gravel, sand, silt and clay. Then you can separate soil and rock mass by this method.
Second approach is classification by strength. If the uniaxial compressive strength to be exceed 1 MPa, you can recognize as a rock mass.Following
- Is there a differences in the hologram quality if for acquisition process we use a linearly polarized light or circularly polarized light?
I want understand, how differently polarized light influence on the hologram quality. So, if there are differences, what are they? Thank you in advance!Following
- Analyzing multiple choice questions
I have a data set with a measure that uses short scenarios where participants have to choose one of 5 options as their response. Example:
The parents of a young man, who is working, live in another town. The father has just retired from his job. What will the son do?
a. He will encourage his parents to live at his place so that he will save money for his own use in the future (II)
b. He will encourage them to stay at their own place so they can continue living with their friends and their neighbors (IC)
c. He will encourage his parents to live at his place so that they can all live together (CC)
d. He will encourage them to stay at their own place so that he is not inconvenienced (CI)
e. He will encourage them to stay at their own place and go spend quality time with them enjoying their company (C&I)
What is the best way to analyze this if I want to a) compare whether different groups answered these differently and b) compare whether people's responses about how they would act in this situation is different from their perception of how others would act? (i.e. I have two versions of the questionnaire, one phrased as "what would the son do?" another as "what would you do?")
Any suggestions would be greatly appreciated. I have SPSS and R at my disposal.Following
- Journal articles older than 20 years must be made public. What do you think?
There is a specific period after which a Patent expires. Ironically this rule does not apply to Journals, collection of invaluable amounts of research work carried out by mostly by commoner's money. Isn't it necessary to make research work (older scientific work than 20 years) public?
20-year old articles would contain out of date data, of little value to most. In some fields even 10-year old data can be out of date. The real solution will be the expansion of Open Educational Resource (OER); access to current data, "fresh out of research". That is going to be a topic that will generate huge debate over the next few years.
Of course there is no harm in having access to the 10 or 20-year old journals, so that more people can use them for a literature review.Following
- Are there any good articles about bias in teacher research?
In other words, using classrooms for research clearly cannot be randomly assigned. Teachers are not randomly assigned to a school nor are their students. I would like to review a research article that addresses these biases. Any help would be great!
To reduce bias in educational studies, quantitative educational researchers identify matched pairs of schools or districts. There are many good examples of this. I highly recommend Dr. Patricia Campbell's work. In addition, there are articles that describe how the unit of study impacts the research. Other articles you may be interested in:
Designing High-Quality Research in Special Education: Group Experimental Design by Gersten et al., 2000.
Haertekm E. H. (2013, March). Reliability and validity of inferences about teachers based on student test scores (14th William H. Angoff Memorial Lecture). Princeton, NJ: Educational Testing Service. Retrieved from https://www.ets.org/s/pdf/23497_Angoff%20Report-web.pdf
Sanders, W. & Horn, S. (1998). Research findings from the Tennessee Value-Added Assessment System (TVAAS) database: Implications for educational evaluation and research. Journal of Personnel Evaluation in Education, 12(3), 247-256.
Farley, R. W., Campbell, P. F., Ellington, A. J., Inge, V., & Whitenack, J. W. (2008). R & D: Researching the expansion of K-5 mathematics specialist program into rural school systems (DRL: 0822149). Richmond, VA: Virginia Commonwealth University.
Campbell, P. F., Nishio, M., Smith, T. M., Clark, L. M., Conant, Rust, A. H., DePiper, J. N., Jones, T., Griffin, M. J., & Choi, Y. (2012). The relationship between teachers’ mathematical content and pedagogical content knowledge, teachers’ perceptions, and student achievement. Journal for Research in Mathematics Education, 45(4), 419-459.
Banilower, E. R., Heck, D. J., & Weiss, I. R. (2007). Can professional development make the vision of the standards a reality? The impact of the National Science Foundation’s Local Systemic Change through Teacher Enhancement Initiative. Journal of Research in Science Teaching, 44, 375-395.
Desimone, L. M. (2009). Improving impact studies of teachers’ professional development: Toward better conceptualizations and measures. Educational Researcher, 38(3), 181-199.
Heck, D. J., Banilower, E. R., Weiss, I. R., & Rosenberg, S. L. (2008). Studying the effects of professional development: The case of the National Science Foundation’s Local Systemic Change through Teacher Enhancement Initiative. Journal for Research in Mathematics Education, 39,113-152.
Wayne, A. J., Yoon, K. S., Zhu, P., Cronen, S., & Garet, M. S. (2008). Experimenting with teacher professional development: Motives and methods. Educational Researcher, 37 469-479.Following
- Hello everyone what is the best way to record phone interviews and is it difficult to get a sufficiently high quality recording?
I am beginning a qualitative research project and unfortunately I will not be able to conduct face-to-face interviews with all the participants so will need to do some by phone. Any advice from others who have done this would be very much appreciated.
Thanks a lot.Following
- How can I adjust my old user subroutine with earlier version of ABAQUS?
I want to implement a VUMAT subroutine in Abaqus, but when I do it, the following error displays. Is there anyone who knows what this means?
I use Abaqus 6.12 or 6.14 and visual studio 2008. I am sure that they are linked.
"Problem during linking - Single Precision Abaqus/Explicit User Subroutines.
This error may be due to a mismatch in the Abaqus user subroutine arguments. These arguments sometimes change from release to release, so user subroutines used with a previous release of Abaqus may need to be adjusted."
How can I adjust my old user subroutine with earlier version of ABAQUS?Following
- How long is parthenolide stable in a methanol solution? We only have 5mg of parthenolide. It iis a very small amount, so we want to make a stock solution of it in order to not waste any during weighting. Is it stable in methanol?
Yes, i think it is stableFollowing
- Which feature extraction technique is invariant to rotation (R), illumination (I), translation(T) and scale changes?
I know scale invariant SIFT feature but this technique is tedious. Another features are Histogram of Oriented Gradient HOG, which is efficient and can be rotation invariant. But I didn't find any feature which is invariant to RTI and scale changes and yet it's computation cost is low?
Can anyone please suggest me such features if it exists?
Can I use combination of these feature? if yes, how can I combine them as they have different size?
Try downloading paper titled "Shape Descriptors for Maximally Stable Extremal Regions" by David Lowe and others (The author of Great SIFT Algorithm)- It is based on MSER features which are by definition affine invariant (more correctly co-variant) and the shape based features suggested in literature are illumination invariant. So, in nutshell we get rotation, illumination, scale, translation, shear invariant features. Hope that helps.Following
- How does an image represented in frequency domain?
I am new to frequency domain and i tried following some articles but i find it difficult to understand.
In spatial domain, the image is represented in a matrix form using pixels that holds RGB values(ranging from 0-255) and further it can be decomposed into R,G and B values i.e. pixel P1 with co-ordinates (12,129) may have RGB value 213 and when further decomposed, we obtain R,G and B values.
In frequency domain, how the image is represented? does each pixel has definite values or any other means of representation?
Can anyone explain how it is represented in frequency domain in simple words or recommend any blog/article which will help me to understand basics of representation of images in FQ?
Use the fourier tranform on each image channel (R,G,B). By example, for the red channel we obtain for each pixel (u,v) the amplitude and the "shift" of the frequency uv-th. In many softwares, the amplitude is mapped to [0,255] to show a grayscale image. Another possibility is to compute the vector length of the resulting complex number, and also display a grayscale image.Following
- How can I calculate the fracture toughness of the Kagome lattice using Abaqus?
Hello all, I have modeled planner Kagome lattice with half width initiation edge crack, I applied load and get the max. stress equal to modulus of rupture of the lattice material. Can anyone suggest how to calculate fracture toughness of Kagome lattice using the results of Abaqus model?Following
- How can I put a permanent intrathecal catheter on rats?
I would like to test an intrathecal drug on rats. How can I put a permanent intrathecal catheter or which experiment animal do you suggest?
I've administered drugs intrathecally in rats with permanent polyethylene catheters for many years. The methods sections of any of my papers could help you with inserting the i.t. catheters. I used a modification of Tony Yaksh's method from the early 1980's. Good luck and let me know if you need help. ... TCFollowing
- Can saltmarsh grass be a good source of organic fertilizer? Any recent publications are made on it?
In some parts of California and Nevada Distichlis spicata (salt grass), is baked or roasted in pits, the bottom of which is usually harvested salt. This species is maintained at a salt marsh and alkaline soil at low heights..Following
- How can I save aliquots of mouse primary hematopoietic cells for controls in later experiments?
Can I remove blood and splenocytes from a mouse and freeze them in aliquots to be used as controls for flow experiments? What are the best freezing conditions, and how should the cells be treated?
I am doing in vitro assays with murine T cell lines and I run flow on them for T cell markers. I would like to use primary cells as positive controls for these markers, but I don't want to bleed or kill a mouse every time.
- From geopolitical point of view, how real is the possibility that Iran returns on global gas market and replaces Russian gas?
With 18 percent of total world gas reserves Iran is right behind Russia....Following
- What is the difference between Radio-luminescence and Scintillation?
In a first look, both are fluorescence, giving immediate light emission on irradiation. Mechanism wise both are similar. If both are same then why different terminology? Or is there any technical difference?
Upon excitation with Radioactively created energy regardless of its nature [electrons,positrons,x-rays, gamma rays, neutrons or charged particles] that is incident on say a solid, there is immediate emission of light that may be termed radioluminescense.
The light emission that occurs at a particular wavelength, reaches a peak of emission and decays to 1/e value of its peak intensity in 5 microseconds or less is arbritarily termed a scintillation light and the solid a "Scintillator", the rest are designated as "Phosphosr" with long decay of light after the exciting source has been removed. Yes, scintillators are also found in liquids, ergo Liquid Scintillators, or gases and even plastic. You have, hence, Inorganic Scintillators both crystalline, polycrystalline, amorphous, and Organic Scintillators [The PVT base activated with p-terphynyl, being an example] and Liquid and Gaseous Scintillators whose chief characteristics is that the emitted light is gone within 5 microseconds. I have deliberately not addressed the mechanism phenomena that is attributed to what causes scintillation [relatively short emission of luminescence upon excitation] as this a debatable subject that is not yet settled fully with 100% consensus. Even the most well known scintillator, NaI(Tl), the workhorse scintillator of the industry, there are scientists who will debate the mechanism---Google it.Following
- What is the difference between Jc and Gc ?
I have a question, what is difference between Gc and Jc?
I want to model an elasto-plastic beam with a crack, as we know in elasto-plastic material we should use Jc, and compare J with Jc for crack propagation.
Can I use Gc=Jc or not?
Thanks for your kindly answers....
Use the J-integral when you expect plasticity at the crack tip. Irwin's "G" is used for linear elastic fracture models.Following
- Can anyone give suggestions on how to obtain a calibration curve with correlation coefficient of 0.999?
I have prepared calibration standards by diluting the zinc standard solution (procured from Merck) with deionized water to the desired concentrations. I am using volumetric flasks to prepare the calibration standards before transferring the solutions to the plastic centrifuge tubes. The plastic centrifuge tubes have been soaked in 1% nitric acid bath for more than a week and rinsed with deionized water before use. After three runs using the ICP-OES, I still cannot manage to obtain the correlation coefficient of 0.999. Thank you.
What concentration range are you working in? If low, possibly some lab contamination could affect things.Following
- Does anyone know how to calculate the Cronbach alpha on SPSS?
I mean, how to put the data on the SPSS spread sheet and then to calculate the reliability?
Analyse --> scale ---> reliability analysis, then select all of your scale measures, transfer to analysis area on right hand side, leave all defaults on (cronbach's alpha), select ok and result will be a simple value - if all ok between zero and 1 and hopefully > 0.7
you can also look at groups of common measures (eg if surveys these could be satisfaction measures or importance measures or agreement measures etc) and undertake alpha checks on the groups. Good alpha's are > 0.7 rememberFollowing
- Does anyone here know how to use fractal dimensions to study habitat complexity?
Fractal analysis for rock surface contours
New measure called ht-index and new definition of fractals based head/tail breaks: see the following two papers:
see also this tutorial: https://sites.google.com/site/giscience2014tutorial/Following
- What is the Quality attribute affect the resource management system ?
The most important quality attribute is fairness and response time. what is the other attribute and how it affect resource management system?Following
- Why am I not getting the correct point group when I am doing raman using dft calculation using gauss view?
I was trying to do Raman calculation using Gaussian 9 ( I have used DFT, B3LYP,6-31G basis and my molecule was Zinc pthalocyanine ) but I don't see the correct point group. Can anyone please help me?
I can optimized to D4h symmetry group but i can not do frequency calculation It shows "Inaccurate quadrature in cal D su " error.Following
- Can anyone recommend literature/studies on buried chilled pipelines in discontinuous permafrost?
I am working on a white paper for buried chilled pipelines in discontinuous permafrost. Topics that are covered are frost bulb, thermokarst, slope instability, thaw settlement, subsidence, permafrost disturbance in right-a-way, reclamation, and revegetation strategies. In addition, lessons learned and BPM for trenching methodologies. I appreciate any assistance!
We are assessing the temporal and geographical scope, defining the stakeholders, and analyzing the cost benefit for a potential small scale study.Following
- What is the difference between a typology and a taxonomy?
Often the terms typology and taxonomy are used interchangeably. Yet, I believe there are fundamental differences. What are your scientific views?
Taxonomy: The science of classification as applied to living organisms.
Typology: Classification of things according to their physical characteristics.Following
- Is there an equation relating time and concrete strength?
Is there an equation relating time and concrete strength?
You can find a general model to predict of concrete strength in due time, in a reference book about concrete. It is Concrete properties by Professor Novill.
Thanks a lotFollowing