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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- Does anyone have information on cornea epithelium segmentation?
I have a problem with this - the image has more cells so that makes a problem when I enhance or segment.
Thanks Dr. Muzhir Al-Ani for your answer, actually I tried to work on threshold but I didn't get good result.
Thanks Dr.Wolfgang H. Muss. I'm working on EYE human and I should detect the nerve and cells, but at this stage just on nerve segmentation, and I'II attach to you some picture after enhance it.
I hope you can help me.Following
- What are the current theories in modeling traffic flow?
Suggest some papers regarding the recent theories in modeling traffic flow. Thank you.
Thank you Mr Florian I appreciate your helpFollowing
- AC analisis and Noise analysis Virtuoss 6.1.5?
I want simulate the gain(Vout/In) using AC analysis in virtuoso 6.1.5 but i don't find tuto about this ; second i need also to simulate the input current noise of the system using a noise analysis but i don't find a tuto ; can someone help me please
- Which are the biopolymers used for the topical drug delivery system?
I want to know the list of novel biopolymers allowed to use for the topical drug delivery.
If you're looking for some form of nanocarrier for topical application you need to take into account its toxicity, so maybe think about water soluble polymers that are also biocompatible rather than thinking just about polymers with quick degradation rate.Following
- How to relate topographic map to SAR GeoTIFF image?
I want to know from where I can find the topographic map of world with contour values and latitude longitude, And how can I relate the topographical map and GeoTIFF image from SAR sensors using either matlab or ImageJ.
I have a "friend" who "found" the high resolution surface elevation (land and sea floor) files for the entire Earth on a server (which shall remain unnamed). The files are much too big to Email, but I might be able to find someone else's ftp server that we might "borrow" some space on long enough to transfer the files, if that's what you're looking for. The files are much too big to load into any commercial software, but I can write a little program in C to extract whatever subset you need. The 64-bit version of my graphics program can load anything and can read the files in their native format. It comes with lots of 2D and 3D demos. It also interpolates 2D, 3D, and 4D data, cuts, crops, and smooths surfaces and volumes, extracts contours, surfaces, and shells, and converts various file formats. Here's a link and there's some other software at the second link that might be of interest.Following
- Is there any open-source tools for interactive learning content authoring similar to Adobe Captivate?
What is your favorite learning content authoring tool? I am looking for interactive learning content authoring tools that are open-source and competitive like Adobe Captivate.
You can also try Popcorn Maker.Following
- For immune cell detection in mice, what kind of antibody is the best for each immune cell?
1. NK cell
4. Dendritic cell
5 T and B cellFollowing
- Is it any chance to I find free database of (anonymous) patients with diabetes? e.g. data of metabolic clamp. Looking for data on which I could test an algorithm to predict the trend of changes in glycemia.
Thank you for this link.
- What is the suitable way to check the antibody concentration in serum?
I had immunized mice with recombinant proteins, and I would like to check the raised-antibody concentration in the post-immunization mice serum.
ELISA is the most common way of measuring serum Ig responses and as Ashraf said, if you can't buy a pre-made kit, you need to set one up yourself. The problem is of course the standard, which you use to quantify your sample. To get an accurate estimate of the concentration you would need the standard to be an antigen-specific purified fraction of your serum (i.e. affinity column or something for your antigen followed by OD measurement to determine the Ab concentration).
However, quite often it seems enough with a total Ig standard (e.g. Total IgG [can be purchased from multiple vendors] and detection with a polyclonal anti-serum) as long as the curve fit is very similar to your Ag-specific ELISA (i.e. the curve "shapes" should follow a similar dose response as this indicates a similar binding ratio between Ab-Ag). Using this approach you can then "quantify" a serum sample and then use that as a future reference. As I said, this approach will not give you a perfect concentration but the intra-assay concentration determination will be fine.Following
- Is there any theories relating to the socio cultural environment of entrepreneurship?
Can any one suggest the theories relating to the social and cultural entrepreneurship...
Hi, this book focusses on indigenous entrepreneurship, and a number of contributors highlight the critical importance of culture to indigenous entrepreneurs:
Dana, L-P & Anderson, R. (Eds.), International handbook of research on indigenous entrepreneurship. Cheltenham, UK. Edward Elgar Publishing.
- What diploid DNA plant species can I use as control in DNA ploidy analysis of pearl millet and napier grass using flow cytometry technique?
I would like to analyze DNA ploidy level in pearl millet and napier grass using flow cytometry method. I would require a known ploidy DNA plant as control. Please, kindly help out if you know for sure a diplod DNA plant species.
Alternatively, you can choose a plant from the Plant DNA C-values Database:
- Conservation biology: a fixist view of life?
All too often, people talking about biodiversity or ecosystem preservation (be it in the frame of climate/global change or of mitigation of other human activities, like agriculture or urbanisation) convey a message that we should basically maintain the current state, implying that any change would be for the worse and that human actions can only damage nature, not improve it. This somehow ignores the very principle of evolution - which means (in Darwin's words) change through descent with modification. There are attempts in conservation biology to use evolutionary processes (like in the dynamic management of genetic ressources used for some agricultural species), but these are marginal compared to the dominant 'preservation as identical' position. Aren't we missing the whole point of life evolution and of man being part of it when advocating to preserve the current status, rather than allow nature to evolve with us?
A dynamic view of conservation has been present in the field of conservation biology pretty much since its inception. There are many ways conservation has considered how communities change over time, for example in the context of Holocene range shifts, historical and current land uses and uses of wildlife by all kinds of cultures, wildfire and prescribed burning, wind disturbance, road building, agriculture, and so on. In fact it is difficult to have a serious conservation conversation without considering change. In some ways the field of conservation biology is all about detecting how change on different temporal and spatial scales influences distribution and abundance of organisms.
Here are a few:
Hunter Jr., M. L., G. L. Jacobson, and T. I. Webb. 1988. Paleoecology and the coarse-filter approach to maintaining biological diversity. Conservation Biology 2:375-385.
Delcourt, H. R., and P. A. Delcourt. 1997. Pre-Columbian Native American use of fire on southern Appalachian landscapes. Conservation Biology 11:1010-1014.
Delcourt, P. A., and H. R. Delcourt. 1998. Paleological insights into conservation of biodiversity: a focus on species, ecosystems, and landscapes. Ecological Applications 8:921-934
Foster, D. R., F. J. Swanson, J. D. Aber, I. Burke, N. Brokaw, D. Tilman, and A. Knapp. 2003. The importance of land-use legacies to ecology and conservation. BioScience 53:77-88.
Foster, D. R., G. Motzkin, D. Bernardos, and J. Cardoza. 2002. Wildlife dynamics in the changing New England landscape. Journal of Biogeography 29:1337-1357.
Vandermeer, J., and I. Perfecto. 2007. The agricultural matrix and a future paradigm for conservation. Conservation Biology 21:274-277.
Anderson, M. G., and C. E. Ferree. 2010. Conserving the stage: climate change and the geophysical underpinnings of species diversity. PloS One 5:e11554.
An earlier comment also suggested that diversity goes up when invasion happens. Sure, especially early in the land use change trajectory, but when tracked through time and space species turnover occurs, as can homogenization:
Hepinstall, J. A., M. Alberti, and J. M. Marzluff. 2008. Predicting land cover change and avian community responses in rapidly urbanizing environments. Landscape Ecology 23:1257-1276.
Scott, M. C. 2005. Winners and losers among stream fishes in relation to land use legacies and urban development. Biological Conservation 127:301-309.Following
- Why do we use schottky contact and not ohmic at the gate terminal?
I assume that you mean a MESFET-type device or something of the category.
The reason for a Schottky contact is because it allows to deplete the channel of carriers. One of the most important properties of a transistor is the magnitude of the on/off ratio. To obtain that you need the channel to be fairly insulating at the 'off' state. The next 'step' would be a MOS/MIS-FET that has the advantage of lower gate leakage by the addition of a gate insulator.Following
- Can anyone tell me level of zeta potential of SiO2 and alpha Al2O3 nano oxide in nickel-phosphorus electroless bath?
In order to production of nanocomposite coatings..
No problems. Here is the article of my boss where needed parameters of both oxides are described. You'll find interesting data in this paper for your further study.
- Has anyone used Respondant Driven Sampling to research undocumented migrants ? The ego-centric approach relies on questionnaires designed by the author who involves the 5 other Algerian women, called seeds. Questionnaires will be then given to ‘nodes’, direct personal ‘ties’, and elements of those ‘ties’. It is an ideal method for studying the effects of social networks on individuals (Mardsen 1990). The advantage of ego-centric analysis is its focus on the individual or ‘node’ as the main element of analysis. In many cases, researchers are not able to contact all respondents directly and must rely on alternative information collected from the initial contacts which might end up with missing important information. For this reason , the researcher will combine RDS, snowball and ego-centric sampling to maintain the ability to reach reasonable statistical deductions (Salganik and Heckathorn 2004). In fact, RDS is now widely used to study any hidden group or populations through the globe, such as drug dealers or HIV (Malekinejad et al 2008).
I have used RDS and the survey to recruit respondants. I couldn't use the program on the RDS website.Following
- Does the severity of post traumatic stress disorder (PTSD) correlate with the core culture and military culture of a nation?
I have been conducting comparative studies about the presence and severity of PTSD in the modern American military and the Roman military of the late Roman Republic. PTSD does not appear to have been as much of a problem in ancient Rome as it is in modern America. Does culture play a role in the vulnerability of soldiers to this anxiety disorder? I wonder if PTSD is less of a problem in the North Korean military than it is in the American military because of cultural diffrences.I am not a psychiatrist or psychologist. However, I am a Consultant Pharmacist with a specaialty in pharmacotherapy.
Dear Seth and Apryl,
Thank you both for your thoughtful comments. I believe that the correlation between culture and vulnerability to PTSD is frequently overlooked by scholars. If any members of researchgate are psychiatrists or clinical psychologists, your comments would be a valuable contribution to this discussion.Following
- Is there anyone who knows where to find a dialysis membrane in a polysulfone or in any other material but cellulose?
Non-cellulose dialysis membranes?
I agree with Jenny. We have been using polysulphone Fresenius/gambro diaylsers for years. You may struggle to find contemporary evidence to support the use of cellulose filters as the industry has pushed away from these products as more biocompatible options are now available.Following
- Can I do an association analysis (using SNP) for agronomic traits sown in one location with two replications only?
I tested 189 faba bean lines in field with two replications in one year and assessed a number of traits. These lines were genotyped using SNPs (156).
Do you think that I can do association analysis for these traits? and
Do you think one year and two replications are applicable to do such analysis?
Ahmed, you can report such data as preliminary in conference poster or abstact (some accept papers up to 4 pages) or write a draft of paper and place it at http://arxiv.org/archive/astro-ph, but maybe, it would be better to find a student/researcher who will continue your experiment for one more season?Following
- How do I design a controller for my system?
I have a 4th order strictly proper transfer function. I want it to track a desire trajectory. I have chosen feedforward structure and I have put the feedforward path as the inverse of my system in order to have zero steady state error. How can I design a controller for this system to keep the poles of the closed loop system on the right side of the imaginary coordinate?
Mr Noshadi thanks for your help. you are right I was mistaken I meant to keep the poles of the closed loop system on the left side of imaginary coordinate.but for the designing the controller my system has two paires of complex poles and the root locus of this system has some paths on the right side of the imaginary coordinate and my aim is to keep the poles of the closed system on the left side for all gains.since my system is strictly proper ad it has no zeros I have to add at least 3 real zeros in order to reach this aim thus my controller is an improper system with 3 zeros and it is not implementable and also simulating an improper transfer function in Simulink has difficulمity.it usually gives error with derivative parts and I don’t know what to do with simulation can you help me with this problem??by feedforward path I do the tracking very well but with a PI control I cant keep the poles on the left side . in my opinion by designing a controller for a feedforward structure we try to keep the poles of the closed loop system on the left side for all frequencies.we don’t have any problem with performance since our tracking is completث???!!!!!!!!!Following
- Curious: Why pulse vortex?
I'm just curious what the advantage of pulse vortexing is over continuous vortexing. I see that many vRNA isolation kits recommend pulse vortexing when mixing (often somewhat viscous) samples with the lysis buffer. I'm sure it aids the process but curious to know exact mechanism. Thoughts?
When resuspending magnetic beads in solution, I've noticed that pulse vortexing works much better at dissolving thick clumps of beads. My thought has been that, at fairly constant speed, the material moves together and so doesn't separate much. However, pulsing produces varying speeds increasing shear on the material and pulling apart the clumps.
If anyone has a more technical explanation, I'd love to see it!Following
- Does green tea extract increase hepatotoxicity? Based on recent studies, grean tea extract besides antioxidant activity and thermogenic features may reduce liver diseases.
Drinking green tea has not been associated with liver injury or serum aminotransferase elevations. Besides, there would be world health threat because tea is the second liquid consumed in the world after water.Following
- Has anyone got or had experience of blinatumomab for Acute Lymphoblastic lymphoma ?
Patient7: 67 yr old refractory to HyperCVAD awaiting donor match, looking for best bridging therapy likely intolerant to Asparaginase, attempting Flag-IDA clofarabine too expensive
- Possible application of light-sensitive organic molecule which can generate electrical potential or signal?
Assume that, I have a molecule that can detect and generate an electrical signal for different wavelength of light, what are the potential advantages of / use of such a molecules?Thanks for your ideas
Thanks Oliver and Adam.Following
- Didactic of calculus differentai exist?
the same choses
yes exist thisFollowing
- Does anybody have information about the process of using milk protein casein to produce fiber? I would like to have some details about the process of producing fiber by using milk protein casein. How much fiber can be produced using 1 kg of milk? How much does it cost? Does anybody have some sort of protocol and would like to develop some collaboration?
You will get about 24 to 28g of casein from a kilogram of milk.Following
- Does anyone have some reference or protocol on cultures of skeletal muscle cells deficient in zinc?
I want to do some experiments in cells deficient in zinc but I only could find protocols in other cell types (for example endothelial cells).Following
- Can anyone tell me why i can not obtain grid value for each x,y in exported table when i add grid value to points in SAGA software?
digital soil mappingFollowing
- How can protect the urban environment to adapt the sustainability development of city in future?
protecting the environment
protecting the historical
adapting the development in plan of 20 years
In my opinion two points are relevant:
- Maintain the maximum green areas and restore those that sprawl already removed;
- Invest the maximum in public transport and in particular by bus with non-polluting sources;
- Accompany the production of industries and their emissions.
- Does anyone have a reference for recrystallization of pure copper cold worked to 500% strain?
Grain size vs time, temperature would be favorable.
Thanx a lot for all your answers. One only needs to browse through older literature. For instance F N Rheines, Met. Trans A, 13A 1982Following
- Which mixture model (2 liquid sample, final mix vlme 35 ml) for food application by design expert would be best?
Simple lattice, D-optimal or any other?
Either simplex lattice if it fits the constraints, else I-Optimal. Use a mixture design for this problem, not a response surface method (RSM).Following