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- Has anyone used the Open qPCR device made by Chai?
Im interested to see if anyone has used this device? Does the cheap cost necessarily mean poor data?
Francesc Codony, has your colleague got his new toy and had a chance to use it yet?Following
- Which best statistical technique can be used on a Point reading of a static data in order to analyse the effectiveness of a particular treatment?
Say for example we are trying to evaluate the impact and effectiveness of a particular poverty alleviation programme where no comparison group is available. We are looking at a data that has to be collected at a single point in time without having any effective way to draw the data for comparison. In such a scenario where just one reading of the data is available, how best can we evaluate the effectiveness of such a programme without compromising the quality of such research.
The book that Zerihun posted has some nice information on impact evaluation and methods. However, there is no credible way in which to measure causal impacts in the scenario that you have given. Without baseline information on poverty (and the process through which your units are selected for the poverty alleviation program...note that this can be relaxed under randomized program rollout) and a comparison group that was not exposed to the program, there is no way for you to infer whether the levels of poverty that you observe are do to the program or something unrelated. All of the methods in the book that Zerihun posted require at least a comparison group (and most are only defensible with measurements both pre- and post-treatment). Fundamentally, in order to measure an impact, one must calculate a difference, whether that be a within unit comparison (before and after) or between group comparison (or even better, both). In your scenario, there is no difference to be taken.
- Which is the best method to make students to choose topics for research ?
These are the need based topics from the Textile Industry
1 Application of enzymes in low temperature soaping .
2. Application of enzymes in colour removal in Textile Effluents.
3. Dyeing of Reactives at Room Temperature.
4. Dyeing &Finishing of Recycled Polyester fibre.
5. Enzymatic Retting of Raw Bamboo fibre.
6. Studies on Bio Composites.
7. Application of Sustainable Fibres .
8. Improving the fastness properties of Natural Dyed fabric.
9. Studies in Salt free Reactive Dyeing .
10. Low temperature Acrylic fibre dyeing .Following
- How can I prevent detachment of retina from choroid during cryostat sectioning of human optic nerve head?
Hi, in my project I am doing cryostat sectioning (Longitudinal section) of human optic nerve head. In cryosection, I have to keep all the three layers (retina, choroid, sclera) attached together but after cryosectioning I find the retina detached from choroid or huge gap between retina and choroid. I think this problem might be due to embedding problem because when I embed the tissue in OCT medium I can’t keep the retina completely attached to choroid. It would be highly appreciated if you have any suggestion to solve this problem.
Thanks everyone for your suggestions. Definitely it helps. However, I want to share my protocol briefly so that you can have better idea about my problem and suggest accordingly.
Yes, it would be better if we could fix the eye before the cornea and lens removal as it allow the retina to remain flat and attached to choroid but the problem is most of the time we receive the eye from eye bank without cornea and lens as cornea is kept for transplantation. So after receiving the eye or better to say eyecup, I fix it in 4% PFA for 2 hours before application of 10%, 20%, 30% sucrose solution for cryopreservation.
Another fact that I must share is, I don't embed the whole eye cup in OCT medium. My particular interest is ONH and the area surrounding the optic nerve head. So, I cut a rectangle shaped area (e.g. 12 mm X 8 mm) keeping the ONH in middle. Then I embed the tissue horizontally in OCT media facing the retina up. As soon as I place the tissue in the OCT medium the retina tend to lift off the choroid a little bit which I can't prevent. Then I do the snap freezing in Isopentane kept in dry ice.
In cryosectioning step, I use the object temperature -20 and section thickness 10 micron. After cryosectioning when I check the sections under microscope I see a huge gap between the layers (retina, RPE, choroid) and I think the gap is justified because it already had gap between retina and choroid during embedding process.
This is the details of my protocol and problem. I badly need to solve this problem. Therefore, I am looking forward to your suggestions. Thanks again for your concern and valuable feedback.Following
- Do you have any reference about wind tunnel test of soil for wind erosion? Where can I buy potable wind tunnel?
Do you have any reference about wind tunnel test of soil for wind erosion? Where can I buy potable wind tunnel?Following
- Are there any references investigating the Xylem ray (Ray parenchyma) of woods in relationship with mechanical properties?
we will investigate the role of Xylem rays (Ray parenchyma) against wood mechanical properties.
For further details about role of the rays in mechanical properties in wood, please see the below link:
- Can anyone recommend the lateset reports or papers about modeling and simulation?
I would like to know anything about the newest development of modeling and simulation.Following
- Does anyone know how to send out "hand shake" signals from the Bruker diffractometers to an external device through any communication port?
We are using a Bruker D8 diffractometer for XRD rocking curve analyses. We are interested in finding out the procedure for sending out Metadata parameters to an external device through any of the existing interfaces (USB, Serial or Parallel) during RSM observations and data collection. Please share your knowledge and experience when convenient. Thanks a million!
A solution is close at hand!Following
- What if ceramics is sintered for too long?
Say mechanical properties and so on
In addition to the classical book by Prof. Kingery, the book by Prof. Kang will be also helpful.
- Does anyone know a set of primers for Trypanosoma vivax?
I would like to check if someone knows a specific and sensitive set of primers for diagnostic of Trypanosoma vivax in cattle.
Totally agree with Dr. Juan David. We use the priemer decribed by Nantulya in our lab
- Can I use nominal data as a covariate?
Hi everybody, I want to determinate the asociation between change of paternity (risk factor, nominal) and the presence of pre-eclampsia (nominal) in a large sample of women. My covariate is intergenesic period (IGP) years between the actual and the last pregnancy) and it has three categories: short IGP (less than 2 years), normal IGP (2-4 years) and long IGP (more than 4 years). I choose this as covariate because an important proportion of women who have changed partenrs usually have long intergenesic period (more than 4 years). This variable is something difficult to control to me as if I only select women with short intergenesic period my sample will be reduced dramatically. As we know, long intergenesic period favors the onset of pre-eclampsia.
Any idea of what kind of analysis I could perform? Obviously, odds ratio is my best option in this case.Following
- Why does multiphoton (2PA/3PA) absorption induced PL show narrower FWHM as compared to the single photon induced PL?
In the context of semiconductor thin film.
My shallow opinion:
Since multi-photon (2 or 3) absorption is the simultaneous absorption of multi-photons to excite a molecule from one state to a higher energy electronic state, and it requires higher excitation intensity, it has smaller rate of occurrence and hence, the linewidth is smaller (similar to probability distribution).Following
- Is it possible to use FAO-UNESCO in conducting soil sample in the Philippines?
If not, what are other ways to standardize soil sample without using FAO-UNESCO classification?
Dear Dr. Stepien thank you for the suggestions. The main reason for the determination of the soil property is to standardize the soil and assure that other factors like you mentioned are nearly, if not the same, in all soil sample. This will ensure that these properties does not necessarily affect the effect of the phenomenon that we are studying in microbial community proliferation in that areas. Can this be done completely?Following
- What is the atomic or weight percentage of Silicon and Nitrogen in stoichiometric Silicon Nitride?
I have deposited Silicon nitride by RF sputtering technique using stochiometric Si3N4 target. I used Ar gas only. The chamber was evacutaed at 4x10-6 torr prior to deposition.
The EDX analysis showed a large amount of oxygen in samples as shown in attached figure.
Can anyone please help me analyzing this data.
- What is the atomic percentage of Si and N in stochiometric silicon nitride.
- What is the source of large amount of oxygen in my samples ?
- Why the percentage increase or decrease is not linear with sputtering power?
Thanks in advance.
Your chamber volume is ~112 liters, which is a moderate size. You should check the ultimate pressure specification for the turbo pump. Unless it is a small pump, you should be able to reach a lower base pressure than 4x10-6 Torr. You should be able to run the vacuum pumps with the sputter gun water cooling off to see if the chamber pressure decreases.
With a Si3N4 thickness of only 200 nm, most of the EDX signal could be from the underlying 1,600 nm thick SiO2, which is probably the source of the high oxygen signal. Sputter Si3N4 directly on a silicon substrate and see what you get. But you have SiON if the index of refraction is 1.75.
Numerous surface analytical methods (SIMS, XPS, AES) could be used to determine the composition of Si, O, and N in your films, but you would need a sample of known composition as a standard. Rutherford backscatter spectrometry (RBS) can measure the composition and does not require a standard.Following
- How does being bilingual affect a person's identity?
As language and culture are intertwined, I was wondering how a bilingual person develops his/her cultural identity. Does the person acquire the culture of L1, or that of L2? I'd appreciate your opinion.
@Laura... and this broadening is a gain too right? Or do you see it as a loss (because of the "weakening" of the original culture)? Then we adapt (as all humans do) and we become different. We evolve. As Popeye used to say: "I am what I am".
@Matthew - which is the culture behind English (unless you postulate that there are dozens of Englishes)? I chose English because of its special status, but this applies to all languages actually. Oh and the Whorf-Sapir revival (at least in its weak form) is real... Look at the Lera Boroditsky studies and the Himba tribe in Namibia. Fascinating... In any case, beyond "spaghetti" culture, it is unlikely that real culture can be taught though it can obviously be learned (I am not suggesting that you think it can be taught by the way - it's just to counter the common idea that "you have to teach the language and its culture").
Also, in relation to @Alexandru's point... as a multicultural person, is it possible to establish boundaries between the two (or more) cultures? Will I only laugh the French way when I watch a French movie or the Greek way when I watch a Greek movie or the Thai way when I watch a Thai movie etc??? Or???
Just some thoughts...Following
- Other than ITO, what kind of material are possible to be the top and bottom electrode in optical waveguide?
I'm using ITO because it is transparent and it have high melting point up to 1900(if i'm not mistaken).
If transparency is not a concern, metal could just do the job.Following
- How to study dynamic protein-protein interaction in living system ?
I want to check interaction of a protein with another protein which does not make complex. Their interaction is dynamic.
Which is the simplest way to identified this type of dynamic interaction? And please provide all other possible method to investigate dynamic protein-protein interactions in living system.
Yes, the other approach that Arnoud suggested BiFC (bimolecular fluorescence complementation) should work as well. Both methods are technically very challenging though. Cloning of several constructs will be required and you need to do many controls experiments first prior to testing the protein-protein interactions.Following
- What are the differences between CPU and CFU in enumerating bacteria ?
What are the differences between CPU and CFU in enumerating bacteria ?
- CFU is Colony Forming Unit; unit used in the measure of Total Bacteria Count (TBC).
- CPU is Chloroplatinate Unit (color indicator).
- In Microbiology, colony-forming unit (CFU) is a measure of viable bacterial numbers. Unlike in direct microscopic counts where all cells, dead and living, are counted, the CFU measures viable cells. A sample is spread or poured on a surface of an agar plate, left to incubate and the number of colonies formed are counted.
- CFU number is not an exact measure of numbers of viable cells, as a colony-forming unit may contain more cells.
- Further reading at https://answers.yahoo.com/question/index?qid=20060905195956AA0WDC1
- Can any one kindly advise me with a dye dissolved easly in alcohol and does not in water?
I need a, dye dissolved in easly volatile alcohol and will be stable under the action of waterFollowing
- What are the best physiological measurements for psychological wellbeing?
we are interested in investigating psychological wellbeing from physical activity in green spaces and wanted to use physiological measurements ... Does anyone have any ideas? Heart rate etc. won't really work aS participants will be physically active, the measurements will need to be taken in the field and they will need to assess not only reductions in things like stress ... But also more positive psychological outcomes .. So cortisol, dopamine etc might be ideal? But what else and how?
Have you considered serotonin? Serotonin is a biomarker for psychological well being. A subjective measurement would be to administer state trait anxiety inventory to assess participants anxiety levels.Following
- What would be the reason(s) why geodesic dome homes are not used more widely - in developed and developing countries?
The dome shape (or similar) has been around for a long time. I am curious as to what the reasons might be for not using this building method more widely.Following
- How long does CA-MARKOV Module in IDRISI Selva processing take?
I want to predict 2013 landuse change based on Markovian stochastic model using CA-MARKOV module.It takes long time, sometimes 24hrs to 3 days. What might be wrong?
I have already run MARKOV module to cross tabulate 2000 and 2006 Landuses. I have suitability maps in Raster group file(each stretched 0-255 integer values), i have also the Markov Transition area file. I am now using 2006 Landuse to predict 2013 Landuse change, where i specified 7 as a Number of Cellular automata iterations, 5 x5 filter.
I have also checked the disk space i have 45GB, RAM is 8GB,
Other computer specifications :Windows7 , Core i3.
Software in Use:IDRISI SELVA v17.00
The process runs well and pass from step 1 to 8, then in step 8 when starts "mola" process, it stays there for so long more 24hrs-5 days, before i terminate it.
Anyone with similar experience? Please help.
Thank you very much. I have changed the pixel size to 5m x 5m and run the process. I hope it will work and give results sooner.
- Is my statement correct?
in one of my ongoing research I wrote the following:
"The Triple Helix describes an evolutionary process and the implications of interaction among university, industry and government. In such environment, high process of selection constitutes a key element for the emergence and the success of the hybrid organisations"
please, whether this statement is correct or shall I revise it?
I'm sorry, I misunderstood. Your explanation was profound enough that I assumed you meant grammar, as your explanation is correct and expresses your intentions well. Your description of the Triple Helix is also extremely succinct and direct. I do invite others to agree or disagree, but I believe that you have an excellent statement.Following
- Patch Antenna Simulation Problem?
I am designing a patch antenna for GSM applications. The antenna design consists of patch structure on top. I am not using any ground plane on the bottom side.
How to simulate this kind of patch antenna in HFSS. I have tried lumped port and wave port excitation, every possibility of radiation box, but did not get required results.
Can anybody help me with the proposed problem.
Basically, patch antenna is based upon the microstrip antenna. The ground plane or conductor is required to support wave propagation.
If the ground plane is removed, the patch metal structure is similar to a wire in the space and you need to model accordingly.
A wire in the free space can radiate in line with monopole or dipole antennas. Therefore, you can model the wire as these antennas.Following
- Am I wrong to say that a product of protoplast fusion is not a GMO?
This is the definition I know:
genetic modification involves the mutation,insertion, or deletion of genes. inserted genes usually come from a different speciees in a form of horizontal gene transfer. in nature this can occur when exogenous DNA penetrates the cell membrane for any reason. to do this artificially may require:
attaching the genes to a virus
physically inserting the extra DNA into the nucleus of the intended host with a very small syringe
with the use of electroporation
with very small particles fired from a gene gun
protoplast fusion is a type of hybridisation.Following
- Will Cloud Services replace the Microsoft Desktop ?
Thanks in advance for your replies.
Dear Majzoob, Cloud Services cannot totally replace. They will supplement and enhance the features and user satisfaction to a large extent.Following
- Are there relationships between servant leadership, culture, and performance?
Servant leadership is often presented as having positive impact on employee behaviour and corporate performance.
I wonder if this positive impact is absolute or depending on dominant culture and values.Following
- Does anybody know why 1H NMR spectrums of methylcellulose gives a peak in region 1 ppm? Several times I got 1H NMR spectrums of methylcellulose and obtained peaks in the 1 ppm. I tried to get the 1H NMR spectrums of carboxymethyl cellulose and hydroxypropyl methylcellulose, but they also gave me this peak. In the literature I could not find any information about this peak. Can you prompt if anyone knows?
Please see the attached on probe background signals. I hope that it answers the question and clears up much of the confusion. Look also at the spectra in the reference that Adel Amer cited; you will see the probe background signal. Best of luck in your research.Following
- I would like to know more about an offshore spar truss platform, dimensions are 20m diameter and 80m length. How much steel/iron/materials do I need?
My research is about the life cycle assessment of an ocean thermal energy conversion system and I need to make a quick estimation of the materials needed to build an spar truss patform
Not true. as a progressive construction, just like for a ferro-cement ship (largest was a WW-1 freight ship), or cistern, or even biogas digester.. Gunnite ferro-cement homes can be framed at one end, before spraying, and the other finished before the sprayer does. It's a matter of not allowing the successive sections to cure in between, but to keep it fairly continuous, once started.Following