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  • Noble K Kurian added an answer in Melanins:
    Are Kojic acid and Sulcotrione autoclavable ?

    While working on melanin production inhibitors I had gone through this doubt. Any people who presently/earlier worked on these chemicals please help me to clear it urgently.

    Noble K Kurian · Cochin University of Science and Technology

    You are right Yuan.I will filter it

  • Hawa Kouhestani asked a question in Cytoscape:
    MATLAB to Cytoscape file format exchange

    hi everyone. i have plots in matlab graphic format and wanna to load this plot (that is a graph including nodes and edges) in cytoscape as a network but none of the matlab graphic formats is loadable in cytoscape and the other problem is that available matrix  in matlab workscape doesnt give me the desired network graph when i run it in cyto. could you plz help me about this issue? i'm stuck really

  • Yew Meng Chin added an answer in Personality:
    Is it possible for the personality type of an individual to change? (i.e. ISTP to INTP)
    I took a personality test in college and the result was that I am an ISTP. I recently took the same personality test on the internet and was described as an INTP. What do you think may have contributed to this change?
    Yew Meng Chin · Open University Malaysia

    Dear Dr Jay, I do agreed with you , but due to the short fall of 5FM model , low of correlation in most of the finding , it become a 5FM Personality Paradox ! But , I do believe the external situation have the highest impact toward this type so call ed in-consistency . One of the possible solution was , he have to make use of some other cognitive model to fine tune our finding . Like Emotional -Cognitive Processing model and Mischel CAPS model . This is what I am currently doing....But there are too many situation arise during our day to day life , it is very challenging to take care of most of the situation studies. Then, a lot of resources is required ! 

  • Vinod Amritkar asked a question in Extracts:
    What is the solution to avoid the problem of darkening of natural products during vacuum oven drying?

    The purified natural extract when dried with vacuum oven becomes dark in colour whereas the same extract when freeze dried gives colorless product. Even though the vacuum oven drying was carried out at ambient + 10 degree celcius temperature.

  • Anna Castaldo asked a question in Sputtering:
    Aging tests in multilayered sputtered films.

    In your opinion it is correct to use the TTSP (time temperature superposition method) to estimate the activation energy of degradation processes in multilayered nanometric solid films?

  • Wei Jiang asked a question in Interactomics:
    How to prove two locus i found belong to a digenic inheritance in a Mendelian Disease

    i have found some pairs of  genes, bu i did not found their interactome or their pathway, anyone helps?

  • Jaana Tähtinen added an answer in Odontology:
    How could I write a brief guide for doctoral and master thesis?

    We are committed to have a new style, based mainly in research, hard sciences, medical clinics and innovation, also doctoral degrees in public health and odontology. They are quite different one from another, has anyone some suggestion or should I have several models?

    Jaana Tähtinen · University of Oulu

    Dear Rossana,

    From my experience (over 10 years of supervision), research ontologies and epistemologies in natural sciences and social sciences are so different, that I would opt for at least two modes. Even economics and marketing sometimes are so distant, that our guide at Oulu Business School for MSc. thesis mostly focuses on the report (writing style, referencing, main chapters etc). On the other hand, University of Oulu has a common doctoral school, where all our doc.students belong to, from medical to educational sciences, including natural, business & economics, technical etc. There also the written guide is really a master document for the thesis report (book) and each faculty still has the major responsibility for guiding the doc. students.

    Hope this helps a bit.  

  • Louis Brassard added an answer in Russia:
    Do You believe that Russians will succeed economically and culturally with their unfriendly isolationist policies?

    Ukrainian crisis and other developments in Russia have moved this country to an unfriendly and isolationist policies. Do You think Russia will cope with its problems by such isolationist policy?


    Why do you qualify russia's policy: an isolationist policy?

  • Is it necessary to gel purify your PCR product prior to cloning?

    I use PCR to amplify a 2.5-kbp gene and subsequently run the PCR products in 0.8% agarose gel. I get only a distinct band corresponding to my gene of interest. I also do not observe any primer dimers in my gel. When I gel purify my PCR products, the DNA concentration significantly decreases (<20ng/uL), resulting to very low (or zero) transformation efficiency. Is it possible to directly clone the PCR product into my vector without gel purification? How would this affect the success of my downstream experiments? Thank you very much.        

    Abdelahhad Barbour · University of Malaya

    Dear Charles,

    If you are getting a single DNA band only after running the gel, i suggest you purify your amplified product using a column purification ( it is available in a kit just like DNA extraction kits) but it is specially made for PCR- product purification. the resulted product should be adequate for cloning.

  • Shavkat Nizamov added an answer in Optoelectronics:
    How do I perform digital holographic microscopy experiments?

    I want to perform some digital holographic microscopy experiments recently, however, I don't have much experience. I use an experimental setup shown in the attached figure, however, no interference pattern can be observed on the ccd plane. what are the possible reasons? the light is cw 532 nm with horizontal polarization,  ccd is 1/1.8' size, two beams were both expanded. object beam is expanded and collimated. reference beam is expanded by a concave mirror and thus is a spherical wave.

    please help. thank you!

    Shavkat Nizamov · Brandenburgische Technische Universität Cottbus - Senftenberg

    Check the intensities of the reference beam and image beam - they should have similar intensities. The actual ratio of their intensities at the CCD surface depends on your experimental setup (beamsplitter ratio, objective field of view and NA, pinhole diameter etc). Try to block each beam separately and observe whether the CCD image intensity halves.  If not - adjust beam intensities - e.g. by putting neutral density filters or replacing some of the elements of your setup.

    Also check the coherence length of the laser and the beam path length in your setup - 532nm should have quite long coherence length but who knows.

  • Mohammad Shirdel added an answer in Steel:
    What is the minimum carbon content that occurs twin martensite transformation?
    I observed twin martensite in a low microalloy steel. The steel contains very low carbon content. So, I want to know the minimum carbon content that occurs twin martensite transformation.
    Mohammad Shirdel · University of Tehran

    The amount of SFE is the most important reason which controls the martensitic transformation directly. It is believed that the SFE >18 mJ/m2 is pleasure condition for mechanism of austenite to twinning to martensite by straining. 

    I also verify E. Garcia-sanchez answer.

  • Louis Brassard added an answer in Marxism:
    Is Marxism relevant in the 21st century?
    Is Karl Marx still relevant? He lived in the 19th century, an era very different from our own, if also one in which many of the features of today's society were beginning to take shape. A consideration of the relevance of Marx's ideas in the early 21st century might start with separating their outdated elements from those capable of development in the present.
    Marxism has found great appeal as a political thought for several class-based revolution and have been the theoretical basis for the policies and politics of several regimes across the world. However, most governments and rulers have interpreted the political writings of Marx in their own way and consequently; several of the policies of these so-called Marxist states are often dramatically different and conflicting from the basis of Marxism.


    Is the increasing concentration of capital a fact ? Is it a problem? What are the solutions?

  • Can anyone help me in enrichment and purification of small peptide for MS analysis from dilute solution rich in salts?
    I want to extract unknow dipeptides from high salt solution. My peptide is in very dilute concentration about 100ng/ml with total volume in 10ml. I am planing for SPE but confused about the selection of methodology used.
    Prasad P Kulkarni · Agharkar Research Institute

    Depending upon the salt concentration you may opt for freeze drying all the sample and then extact peptide in a small volume using standard liquid extract methods.

  • Anna Castaldo added an answer in ZnO:
    How to identify ZnO clusters from Zn doped TiO2?

    Can someone tell about  ZnO identity and band gap (If clusters formed) from Zn doped TiO2.. How to identify with raman and XRD instrumentation ?

    Anna Castaldo · ENEA

    From Raman: E1(transversal) 437 cm-1 A1 (transversal) 380 cm-1 ; A1 (longitudinal) 583 cm-1, A1 (longitudinal). A1 and E1 are active also in FTIR.  Clusters of zinc oxide should have a bandgap major of the 3.3 eV. By means of Tauc plot method you can obtain this information from UV-VIS transmittance and reflectance measurements.

  • Rana M. Jamous added an answer in Particle Size:
    Can someone refer me to articles on particle size for making powders of herbal medicines?

    I am working on a thesis using a polyherbal formulation of several herbs and looking for merits and demerits of large vs. small particle size, 80 sieve, 120 sieve, fine, coarse, very fine....  Can someone point me to some reading, esp if it is in Bhaisajya Kalpana and Ayurvedic pharmaceutic?  I think pharmacies that make powders must have examined this issue, but can't find anything...

    Rana M. Jamous · Biodiversity and Environmental Research Center


    you might find this article of interest for you.

    Good Luck

  • How can I run PGLS with a tree which has no branch lengths?

    I want to do some interspecies comparative research. And I'd like to run PGLS in R. But I've got a tree with out branch lengths. The common ways to run PGLS need a tree which includes branch lengths. Then how shall I do it with a tree without branch lengths? How shall I set the branch lengths to make it adequately statistic? what's the detailed codes? 

    Adrian V Jaeggi · University of California, Santa Barbara

    Hi Xiao,

    A phylogenetic tree without branch lengths is essentially equivalent to a star-shaped tree, in which all species evolved independently since their last common ancestor- hence we don't know anything about non-independent evolution, i.e. the correlation structure between species so we cannot control for it. The PGLS then reduces to a normal GLS analysis. 

    So either you find a tree with branch lengths (what kinds of species are you looking at?? there are good trees for a lot of species out there) or you revert to normal regression analysis, being unable to control for phylogenetic non-independence.

  • Silviya Nacheva added an answer in Neuropathy:
    As a clinician, what is the first test- in your practice setting -that you order to substantiate a suspicion of small fibre neuropathy?

    How to stratify tests showing small fibre neuropathy? 

    Silviya Nacheva · Alexandrovska University Hospital

    If, by so far, there is a "golden standard" for affirming SFN this would be through 3 mm punch skin biopsy  and gaining the value of IENFD. No other test could be as exact, although there are statements that microneurography the next possibility, or even equal to PSB. There are other tests as well- quantitative sensory testing, autonomic function measures and so on. For example:

     Devigili G,  Tugnoli V,  Penza P et al. The diagnostic criteria for small fibre neuropathy:
    from symptoms to neuropathology. Brain (2008), 131, 1912-1925

    J.D. England J.D, Gronseth G.S., Franklin G. et al. Practice Parameter: Evaluation of distal symmetric polyneuropathy: Role of autonomic testing, nerve biopsy, and skin biopsy (an evidence-based review) Report of the American Academy of Neurology, American Association of Neuromuscular and Electrodiagnostic Medicine, and American Academy of Physical Medicine and Rehabilitation. Neurology 2009;72;177

    There are many other sources. If I missed something, please accept my apologies.

  • Amin Moodi asked a question in Data Fusion:
    What kind of sensors does Adaptive Cruise Control (ACC) use for it' measurements?

    ACCs can work correctly and precise with measuring data and processing them, what kind of data and how does it get them, (with what kind of sensors), does it use data fusion methods, please link me to some sources to continue my research...

    Thank You


  • Mostefa Benhaliliba added an answer in Sputtering:
    Is there a method that can be used to grow several nanometers films (<10 nm), especially semiconductor thin films?

    And the films are continuous. (Exept MBE).

    What about sputtering methods?  

    Mostefa Benhaliliba · Université des Sciences et de la Technologie d'Oran Mohamed Boudiaf

    sol gel spin and dip coating process are also suitable for your request

  • Sachin A. More added an answer in rRNA Genes:
    Why is the v3 hypervariable region of 16s rRNA gene most suitable for distinguishing all bacterial species to the genus level?

    In several DGGE analysis publications it is proven to give the highest species richness compared to the other hypervariable regions. What is it in this region that makes it highly species-specific?

    Sachin A. More · University of Agricultural Sciences, Dharwad

    As 16s rDNA is highly conserved gene seq. throughout the bacterial domain. 16s gene contains varibale and conserved region. Among the variable regions of 16s gene v3 is highly variable region which can distinguish bacterial subtypes on dgge if amplicon contains this v3 region rest part of the gene is highly conserved. So closeley related bacteria cant be distinguished by banding pattern on gel. So distinguish among closely related bacteria amplicon must contains hyper varibale regions.

  • prof V.S Muralidharan added an answer in Impedance:
    Can anyone tell me the process for measuring impedance?
    Our laboratory has VMP3 from bio-logic to measure impedance. However, whenever I try to measure the impedance of my sample, it has too much resistance over 300 ohms. I think it's because of the distance between the working electrode and counter electrode in the cell.
    Can anyone tell me the exact procedure for measuring impedance for getting nyquist flot?
    It doesn't matter which equipment you are using.
    prof V.S Muralidharan · Central Electrochemical Research Institute

    check for the version of the ppt

    mine is older one around 2007

    best of  luck

  • Steven Rocker added an answer in Time Perception:
    Why does the time perception change when we feel good and when we are suffering?

    Apparently time perception is different according to different emotions. Time is relative, but emotions can change time perceiving in a similar way in humans. Fear and empathy as an example, speed up our heartbeat and breath. Time perception differently from the heart and breath slows down with fear.

    Steven Rocker · Universidad Pedagógica y Tecnológica de Colombia

    The perception of time can be chage becasue many physiological processes are involved. When we try to find out causal factors relative to time perception  we have to main theories: a biological clock and cognitive clock.

    The biological clock have a large list of brain structures involved such: hypothalamus, hypocampus, basal ganglia, These structures provides a feedback to body to keep a circadian rythm.

    The cognitive clock: is about a mental model of time processing, this mental model engage some psychological processes like attention, memory an sensation.

    The emotions have two principal compunds: a physiological response and a cognitve factor. so in order to answer your question you have to establish a relationship between emotion and biological-cognitive clock.

    Maybe the unpleasent situation can be estimated as more long because your attetion is focused in the immediately experience. 

    you should take a look to this papers:

  • Vishwatosh Mishra asked a question in Books:
    What is the fundamental difference between modulation instability(MI) and Four Wave Mixing (FWM)?

    The standard text books say that MI and FWM are the different descriptions of the same phenomenon. These say that the MI is the temporal description of the breaking of a CW into pulses. The same thing when viewed in frequency domain manifests itself in the generation of symmetric sidebands around the pump and this is called FWM. But I have doubts regarding that when multiple FWM process is described, why the MI and FWM are treated differently?

  • Prasad P Kulkarni added an answer in Iron:
    Iron shows +4 and +6 oxidation state but not +5. why?

    Is there any specific reason for the same?

    Prasad P Kulkarni · Agharkar Research Institute

    Certain geometries and associated orbitals are not favorable of +5 OS. But I am sure there could be exception.

  • Mark Hemstedt added an answer in Reductionism:
    Can you suggest a stress scale for foreign domestic workers (live-in maids)?

    I am looking for the best stress scale to use with Foreign Domestic Workers FDW (live-in maids) here in Singapore. My dissertation would consider a possible reduction in stress by teaching the FDW a somatic stress reduction technique. The majority of the FDW will be from the Philippines but will be able to read and write in English. I'm unclear whether an occupational stress scale versus a general stress scale would be better. Although stress is likely to come from their work, the fact that they live away from home in another person's home, often with very few rights or benefits, adds a unique element to the stressors they experience. Any guidance would be much appreciated.

    Mark Hemstedt · University of Liverpool

    Dear Ben, many thanks for your answer. My current draft proposal suggests the DASS21 and Perceived Stress Scale (PSS).

    The research question is "Does the teaching of, and regular practice of, Tension Release Exercises (TRE)™ reduce stress in Foreign Domestic Workers?. 

    A wait list approach is to be used for a control.

    I will read your paper with interest.

    If you have not heard of TRE you can find information at www.traumaprevention.com

    Many thanks. If you have any other ideas I'd love to hear them. I'm not sure if it's possible to review my draft proposal with you.


  • Meysam Arvan asked a question in Project Proposals:
    Is there any study concerning industry-university relationship with an case study of famous corporations?

    I am working on a project for proposing a model that carries out the relationship between aerospace industry and universities or research institutes. The purpose of the model is to make an environment in which the industry can use the knowledge and technology produced in the universities for its development. 

  • Two basic principles to the electrochemical machining

    That there are two fundamentally different principles of ECM has been known for more than 40 years. Here, the ablation volume is determined by both the Faraday law. Formerly referred to as external and internal ECM, a clear distinction is today by the pulsed process energy sources again both necessary. Principal difference is the provision of erosion-effective amount of charge, either by the current process provides the energy source or transshipment of the double-layers.

  • Rohit Pant added an answer in Functional Materials:
    In Field Emission (FE) measurement of thin films which thing more important "surface morphology" or their "bonding environment"?
    • In Field Emission measurement Eturn ON (threshold voltage), Jmax (maximum current density) and Beta (field enhancement factor) are main important parameter......What is more important?
    • Where Beta is directly dependent on surface morphology but some scholars calculating it with the help of work function of the material ..... What is most appropriate method to calculate Beta? 

    Rohit Pant · Indian Institute of Science

    It is better if their SEM shows some needle like structure as the same is important for field emission....for more info you can follow this paper


  • Meysam Arvan asked a question in Project Proposals:
    Is there any study concerning industry-university relationship with an case study of famous corporations?

    I am working on a project for proposing a model that carries out the relationship between aerospace industry and universities or research institutes. The purpose of the model is to make an environment in which the industry can use the knowledge and technology produced in the universities for its development. 

  • Is someone familiar with metabolite identification?

    I need help for metabolites identification from a ion trap GCMS. Can anybody help me out? I have done untarget metabolic profiling. The result look very good. Now I "just" need to identify the metabolites. It is from seminal plasma. Eradat

    Kambiz Gilany · Avicenna Research Institute

    Dear Robert where do I find MS tables for metabolomics study?