Q&A

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  • Which part of a medicinal plant should be selected for research?

    I am working on a plant (shrub) which has some biological activity traditionally claimed for its roots. As uprooting the plant is scientifically and ethnically incorrect, then what if I start working on some other part of the same plant say leaves or fruits or flowers? How should I justify this change of plant part for research and its use?

    Ghanendra Gartaula · GoldenGate International College, Tribhuvan University, Nepal

    If the root is being used as an ethnic medicine, then you should conduct your research on roots. I do not think you can correlate the phytochemicals contained in various parts of plant. So, better you take consent from the relevant authority and proceed your work. 

    All the best.

  • Why doesn't the theory of institutions apply to many of the economies in the world?

    North's theory of institutions (1990, 1991) has been used by  many researchers and World Bank to advocate developing countries on developing economies through improved entrepreneurial activities.  Since the theory is straightforward but many developing countries failed. Why?

    Beata Stępień · Poznan University of Economics

    Theory is not straightforward at all:), 

    loads of factors play a role here - institutions can be ineffective because they: are not embedded in culture, history, they are time and change resistant, can support only chosen circles of interest groups, the reason of their creation doesn't have to be economic and rational, tools of their enforcement can be ineffective, it can be a clash between informal and formal institutions or incompatibility between formal institutional framework, culture and economics etc... if you are interested I can send you some material about this 

    best regards 

    Beata 

  • Louis Brassard added an answer in Human Rights
    Human rights: How to be dtermined?

    What are the human rights? how to be determined? are they the same or varied? do all people have the same rights?

    please share your valued opinions with great thanks

    All humans on this planet need sufficient food and drinking water everyday. If there is a human right, it should be one.  But it is apparently not a right since billion of human do not have enough food and water.  Or if it a right then it means that the 0,1% richer on this planet do not give a dam about this right because they have the power to change that.

  • Can I use boron tribromide for the demethylation of a methoxy group on a compound which carries also a primary arylamine?

    Do I have to protect the amine?

    Mohammed Ali Hussaini Syed · Indian Institute of Chemical Technology

    In my view there is no issue in using BBr3 for the deprotection of methoxy group in a compound containg free NH2. The thing you need to take care of is the acidity of the reaction mixture. After completion of the reaction, the mixture should be brought to neutral conditions so that amino group should not get converted to its salt and remain in aqueous layer. Otherwise reaction is reported to proceed well. Some examples are enclosed in the attachment

  • Do organizational attitudes determine organizational behavior?

    To what extent, can attitudes affect organizational behavior?

    Tiia Vissak · University of Tartu

    If the attitude is poor (e.g. if employees hate the organization as they think that they have not been treated well - e.g. their salaries are low, but all managers earn much more and the owner has recently bought a private island) then this reflects in their behavior: e.g. high turnover (people leave to find better places), poor customer service or, in some cases, even stealing from the firm to "set the balance right" and this, in turn, will negatively affect its performance.

  • Godfred A Menezes added an answer in Shigella
    What higher generation antibiotics can be used on Shigella species'?

    Hello. I wants to perform Antibiotic susceptibility test and its MIC for shigella species.. let me know the higher generation antibiotics using for shigella sps.

    Godfred A Menezes · Jawaharlal Institute of Postgraduate Medical Education & Research- JIPMER, India (past), Erasmus MC, Holland (past), Sree Balaji Medical College & Hospital (Current)

    Never test/ report the 3rd gen. cephalosporin susceptibility unless it is resistant to all 1st line antibiotics. 

  • How to reduce Immunohistochemistry background signal ???

    I have been doing Immunohistochemistry to detect parasite presence in brain of mouse which had cerebral malaria. I was using parasite specific antibody HSP60 and using secondary antobody conjugated with HRP. I was using DAB substrate which gives brown color precipitate where parasite is present. But i have been getting background more so i was not able to locate parasite presence properly. Could somebody suggest me an alternative approach or help me to reduce background?

    Mohamed A. A. Mahdy · Yamaguchi University

    You can decrease the concentration of DAB and try to shorten the time of developing color

    it may help

  • How can we handle radioactive material in a laboratory (Example: Uranium) experiment? What type of precautions are needed for this?

    Radioactivity is the process by which a nucleus of an unstable atom loses energy by emitting ionizing radiation. That material emits spontaneously this kind of radiation—which include the emission of alpha particles, beta particles, and gamma rays. Rays and particle always affects the health.

    Hanno Krieger · Justus-Liebig-Universität Gießen

    @B.K. Bhaumik,

    it´s a famous rule. In Germany it´s called the triple  "AAA" rule. 

    First A: Abstand = distance

    Second A: Aufenthaltsdauer  = time

    Third A: Abschirmung = shielding.

    The same rules as you and dear Lala already mentioned.

    But you forgot a fourth rule: Never incorporate radioactive substances, that means you must use climate and special facilities, which prevent breathing readiactive matter. And you must take care, that your skin will be protected by gloves, and never handle radioactive materials if your skin is hurt. Close your wounds.

    And the fifth rule: Don´t be pregnant.

  • Margo Bargheer added an answer in Publishing
    Who has experience with Frontiers publishing and editorialships?

    Probably like many of you I am quite frequently approached by publishers to submit my articles to their journal or to sign up as editor for their journals. Many of these publishers are considered to be "predatory publishers" who publish under the "open access" model to charge money from the researcher to get their work published, but who do not always conduct according to the scientific principles of a scientific field. I normally check whether these publishers appear on Beal's list (http://scholarlyoa.com/publishers/).

    One notable exception on this is the series of titles in "Frontiers in.... " (fill in your field on the dots). I'm a bit uncertain whether I should respond to their requests and whether it's genuinly about the sience, or about the money making. Any experiences that would be shared are welcome.

    Margo Bargheer · Gesellschaft für wissenschaftliche Datenverarbeitung mbH Göttingen

    Thomas, at our university we run a publication fund covering APCs for our researchers. Frontiers is one of the most frequently chosen publisher, along with PLOS and BiomedCentral. Although I don't think that the masses are always making the best choices in this case I think it sheds some light on Frontiers. Our researchers trust this publishing house. All our interaction with the publisher is professional and smooth. Hope that helps you in your decision.

    Best

    Margo

  • Victoria Kidgell added an answer in Fibula
    Can anyone advise on where I can access 3D CAD data/geometry of the knee joint?

    I am condutcting research into contractures and I am going to be running finite element analysis of the knee joint. I need to find somewhere I can download CAD data/geometry of the entire lower leg (if possible) including ligaments, tendons and muscles. The structures I need to be included are: femur, tibia, fibula, medial and lateral menisci, gastrocnemius, biceps femoris and semitendinosus muscles and the associated tendons (since these are the structures I am focussing on).

    I have been able to find geometry for the bones and patella tendon, but nothing with the hamstring tendons or any of the muscles. I need the entire bone geometry (not just a cut off bone as in many models) since I need to incorporate muscle insertions. Does anyone have any recommendations at all?

    Thanks in advance for any help you can give me.

    Victoria Kidgell · Robert Jones and Agnes Hunt Orthopaedic and District Hospital NHS Trust

    Thanks Aravind. I have already tried there and found a very good model that incluldes the femur, tibia, fibula, patella, patella tendon, ACL and PCL. But ideally I'd like the hamstring tendons and muscles too if at all possible. Any ideas?

  • Godfred A Menezes added an answer in Ampicillin
    Do you think we are left with the single option, that is "cycling of antibiotics"?

    We are left with the compulsory thought of "cycling of antibiotics". For instance typhoidal salmonellae are now susceptible to older antibiotiocs (Chloramphenicol/ Ampicillin/ Cotrimoxazole) since they are not in use now against them.

    Godfred A Menezes · Jawaharlal Institute of Postgraduate Medical Education & Research- JIPMER, India (past), Erasmus MC, Holland (past), Sree Balaji Medical College & Hospital (Current)

    Cycling of antibiotics is always applicable being individualized to each hospital set up.

    Here the susceptibility pattern has to be monitored for each hospital and depending on this the hospital infection control Committee has to be actively involved in prudent cycling of antibiotics.

  • Are patterns in human designs a mirror of patterns found in nature or are patterns in human designs somehow different from patterns found in nature?
    The word "pattern" in everyday parlance often means something typical that can be repeated, something characteristically capable of repetition into similar copies (Ulf Grenander, Elements of Pattern Theory, Johns Hopkins University Press, Baltimore, 1996, p. 94). For example, in nature one can observe myriads of patterns in plant leaves or in beehives or in branches of trees or in the honeycomb-like shapes in dragonfly wings. Again, for example, in nature definite patterns can be observed in the daily life of animals: waking at sunrise time, finding water, hunting for food, socializing, and going to sleep at sunset time. In each case, there are observable patterns. So then the question arises as to whether the patterns in human geometric designs simply reflect patterns found in nature. Or whether patterns in human designs are somehow different in noticeable ways. For an example of a human geometric pattern, consider a pattern in a Penrose tiling. A penrose tiling (inspired by Roger Penrose) is a non-periodic tiling generated by an aperiodic set of prototiles. For a sample Penrose tiling, see the attached image. A Penrose pattern is self-similar, so the same patterns are repeated in larger and larger scales. Such patterns, introduced by the British physicist and cosmologist, are examples of periodic tilings. M.C. Escher, the Dutch artist, is famous for pictures of periodic tilings with shapes that resemble living things.
    Marvin Kirsh · California State University, Los Angeles

    @James "The word "pattern" in everyday parlance often means something typical that can be repeated, something characteristically capable of repetition into similar copies...." in your question introduction.

           If both brain and mind are the products of patterns repetition, i.e. from [path = memory + intercourse=path], reproducing/repeating patterns have real intrinsic value and maybe exclusively are the MOA of existence regardless of the course and direction they take....where the free will is concerned choices may have positive or negative consequences.

  • Bernd Schmeikal added an answer in Neurophysiology
    What are the advantages and what are the problems of the hypothesis about “retinoid system”?
    Is the hypothesis about “retinoid system” (by Professor Arnold Trehub), as described in “Consciousness and Cognition” 16 (2007) 310–330 and in the other works of Professor Trehub, a plausible hypothesis? What are its advantages and what are its problems? Professor Trehub describes it in the following words: “Activation of the brainʼs putative retinoid system has been proposed as the neuronal substrate for our basic sense of being centered within a volumetric surround –- our minimal phenomenal consciousness (Trehub 2007). Here, the assumed properties of the self-locus within the retinoid model are shown to explain recent experimental findings relating to the out-of-body-experience. In addition, selective excursion of the heuristic self-locus is able to explain many important functions of consciousness, including the effective internal representation of a 3D space on the basis of 2D perspective depictions. Our sense of self-agency is shown to be a natural product of the role of the heuristic self-locus in the retinoid mechanism.” (Abstract, from: Where am I? Redux.) For the publications of Professor Trehub see: https://www.researchgate.net/profile/Arnold_Trehub The question has been already discussed on the folowing thread: https://www.researchgate.net/post/Is_mathematics_a_human_contrivance_or_is_it_innate_to_nature
    Bernd Schmeikal · University of Vienna

    Self referent creation might be diffuse so that we do not immediately see what that thing is like that creates itself. Creator was thought self-referent (see Gerhard Frey). Today we have math of creation from Spencer Brown and Kauffman. But it is true, using thought one ends up with "thoughts are always leading to machine-like explanation because thoughts are helping us to interact with objects." This seems to be one of the few valuable  truths cognition is able to grasp.  Hence my intruding agreement.

  • Nipuna Weerasinghe added an answer in Fluorescence
    Can anyone help with counting cells with fluorescence?

    Hi!

    I have a question about how to determine cells with fluorescence in a given image (transfection efficiency calculation ). For example under a given set of conditions (expose time) cells in an image may have different fluorescence intensities. So how do we determine which cells to count as having fluorescence. How do we decide the cutoff? See the two images attached for example base on the pixel values in the give cell area?

    Thanks for your time on this.

    Nipuna Weerasinghe · The University of Arizona

    Hi Stuart,

    Thanks for your answer. This is really helpful. 

  • Saswat Barpanda added an answer in HR Consultancy
    Can you tell me one new idea/area where HR management expertise can be implemented?

    Rural cluster for cultural and heritage management is one new place..

    you can add one in comments..i am sure  a lot new avenues will come in the way from all my researcher friends...

    Saswat Barpanda · IIT Kharagpur

    There are many organizations where HR activities are there (in fact all organizations), small or large, profit or non profit, manufacturing or services. HR practices is context specific. studying the HR activities/ practices has hardly to do with the necessity of an organized HR departments. the scope of HR can be broaden as the dynamics of industry changes according to context.

  • Godfred A Menezes added an answer in Pathogens
    Is the resistance to Tigecycline (an expected wonder drug) sooner than we ever thought?

    Tigecycline (TIG) exhibits broad-spectrum activity against many Gram-positive and Gram-negative pathogens. However, clinical resistance has emerged recently and has been detected following treatment with TIG.

    Godfred A Menezes · Jawaharlal Institute of Postgraduate Medical Education & Research- JIPMER, India (past), Erasmus MC, Holland (past), Sree Balaji Medical College & Hospital (Current)

    There are couple of publications reporting emergence of resistance to tigecycline. 

  • Woody Lin added an answer in RNA-Seq
    Why are only 10% of the total RiboZero RNA-Seq reads from polyA+ RNAs?

    My friend told me that the illumina's RiboZero captures mostly non-poly A transcripts. The poly+ RNA transcripts will be only 10% of the total reads. Does anyone have such experiences? Could you please share a little bit about your experiences?

    Woody Lin · Taipei Medical University

    @Aliaksei: Thanks for the informative explanations! I learned a lot.

    @Amit: Thanks for sharing the experiences!

  • Olga Urbanek added an answer in 3D Printer
    What kind of 3D printer (name, producer) do you recommend for cell scaffolds forming?

    I would like to print polymer scaffolds for tissue engineering. Are there available any printer which let to achieve high cartridge temperature (300 degree of Celcius)? How much does it cost? 

    Olga Urbanek · Polish Academy of Sciences

    Thank you very much! :)

  • What information can we get by plotting the storage and loss modulus vs energy absorbed by rheology?

    The energy absorbed by the gel can be given as a product of shear stress and shear strain. I came across an article which had plotted normalised storage and loss moduli against the energy. I would like  to know what inference can we get from this type of graph.

    Prabhu Srinivas Yavvari · Indian Institute of Science Education and Research Bhopal

    i am attaching the article where the energy is calculated in terms of stress and strain.

  • Can I use the salt form of dexamethasone instead of the usual forms used in protocols to stimulate osteogenic differentiation in MSCs?

    In most common protocols for osteogenic differentiation the water soluble form of dexamethasone ( sigma D2915) has been used which is a complex of dexamethasone and and cyclodextrin. I just want to know that using sodium phosphate dexamethasone instead will make problem for me or not?

    Ahad Khoshzaban · Tehran University of Medical Sciences

    Dear madam

    You could use the direct salt with step by step addition .Your protocol will  effective   but your differentiation composition.

  • Do you think the "Rule of Thumb" Management Principle given by FW Taylor, is always harmful for organization?

    I would like to know the advantage and disadvantage of the Rule of thumb method given by F.W taylor?

    Jaharkanti Dattagupta · Novel Group of Institutes

    Taylorism was authoritarian and unfair towards labor. Rule of thumb is an approximation based on experience and is more of a guess work without any scientific basis. Hence, is not always correct. Organizational decision making is not      '  rule of thumb ‘ , but the result of systematic process of understanding and analysis of the situation. Any organization works mainly on binary system: technical and human where both are in cohesion . ' Rule of thumb '  is unilateral and does not take into consideration the social system of the organization. ‘ Rule of thumb ‘ may be used in a situation where any decision is better than no decision.

  • Farzane Azimi added an answer in Medical Imaging
    Open/Free medical imaging datasets for academic/research project

    Hi everyone,

    I am looking for some medical images (preferably X-Ray) for one of my researches. Do you know any dataset freely available for academic and research purposes?

    Farzane Azimi · Amirkabir University of Technology

    hi, see www.physionet.org

  • Is it worth publishing with Lambert Academic publishers?
    My inbox has repeatedly been spammed from lambert Academic publishers. Is it worth publishing with this publisher. Do they have any authenticity. There is a lot of bad stuff written about this. Still, people publish their thesis with them. How one could publish your results in the form of book when its already published in the form of research articles. Are they peer reviewed....Suggestions welcome http://chrisnf.blogspot.ca/2010/06/lambert-academic-publishing-continues.html
    Edwin W H Jager · Linköping University

    See the following link:

    http://accrispin.blogspot.se/2009/09/victoria-strauss-vdm-verlag-dr-mueller.html

    It answers most of your questions.

  • Is it possible to determine the amount of Zinc present in the blood of mice other than ICP-AES/ ICP-MS techniques

    I am planning to determine the amount of Zinc released and distributed from Zinc oxide Nanoparticles in in vivo conditions in organs and blood of mice. As cost and availability of instrument is a limiting factor, I would like to know techniques other than ICP-AES/ ICP-MS for the analysis.

    Laurent Y. Alleman · Ecole des Mines de Douai

    I agree with Dr. Sperling regarding the already high Zn content in blood that could hamper your capacity to differentiate the added nanoP Zn from the original one. Indeed, you'll need to add quite a large amount of nanoP depending of the precision of the analytical technique used (ICP-MS is probably best in this case). Hopefully, nano Zn is generally very soluble in blood so you should be able to establish a protocol that match your needs and constrains.

  • Shima Hatamkhani asked a question in D
    Which formula is appropriate for sample size calculation in a study that evaluates medicine use ( DUE / DUR or MUE study)?

    I want to report the percentage of appropriate and inappropriate prescriptions of a specific drug in a hospital. is the formula n=[ z^2 * p ^2  * (1-p) ^2] / d^2 formula suitable, where Z^2 =1.96  d=0.05 , how can exactly know the p ?

  • Ediz Coşkun added an answer in RNA Isolation
    I think I can use the wash buffers which I use in Rna isolation process to purify the my PCR tubes. It can be ?

    Because I have bright bands in the onset of well of agarose gel. I have doubt about contamination. I used a control cDNA to verify PCR process.  I attained the right Dna fragments as I expected. And cDNA ratios is very good my samples like control cDNA. So as I mentioned the title, There is any problem ?

    -I''ll use

    1-wash buffer1

    2-wash buffer2

    3-elution operation

    4- run on agarose gel my samples again ?

    Ediz Coşkun · Istanbul University

     I have a more Pcr samples in Pcr tubes. When  I meant the purify the Pcr tubes actually I meant purify my PCR samples. As you see, above in picture, There is a problem in the first 14 samples. And I have doubt about contamination. I want to additional purifying of my PCR tubes ( Pcr samples if there is ).

  • Nishit Soni added an answer in Agriculture
    Are hybrid varieties of crop plants really so problematic especially with respect to organic agriculture?

    Hybrid crop varieties are often criticized by environmental NGOs (e.g. Navdanya in India; Arche Noah in Austria) for various reasons: seed to seed propagation is problematic; hybrids have high yields and are homogenous in pehnotype but require much input (fertilizers, pesticides etc.). According to these NGOs hybrid varieties are also threatening agrobiodiversity because a few hybrid varieties outcompte a broad range of seed-to-seed varieties. My current understanding is that hybrids are good for an industrialized (organic) agriculture but that non-industrial production conditions require different varieies growing under suboptimal/low input conditions. Likely you have some good supllemental or contradicting knowledge on that issue.

    Nishit Soni · Anand Agricultural University

    According to my view hybrids are not problematic for organic agriculture. But for that we should have primary knowledge regarding the hybrids that weather it is based on  male sterility system by using CHAs (Chemical hybridizing agents), which are chemicals basically used to induce male sterility or it might be by chromosomal techniques by using chemicals or it may be GMOs. If the development of hybrids completely excludes the use of chemicals then such hybrids can be best suited for organic agriculture.

  • Jochen C Meier added an answer in PCR
    What would happen if one forgot to start PCR after putting samples in it?

    Hi, I put my PCR tubes in and forgot to press enter in order to start it. After 1 hour when I was expecting that it would be finished I went and checked that it was never started. Has anyone made the same mistake? If so what did you observe?

    Jochen C Meier · Max-Delbrück-Centrum für Molekulare Medizin

    @  Seth:

    I disagree. The primers are single strand and hybridize with each other or themselves. Depending on the quality of the primer design, e.g. hairpins or simply primer dimers with 3'-OH annealed ends can lead to elongation of the primer and change the 3'-end binding sequence. This part of the primer is the most important one as the PCR amplification starts there, when you finally run the PCR in a cycler. As you can never rule out that such a thing happens, i.e. for reasons of reproducibility, I would rather discard a sample that was forgotten. If your probes are precious, you should not forget running the PCR...

    Best,

    Jochen

  • How can creativity live, grow, or even be expressed in corrupted systems?
    Any views, perceptions, experience?
    Marta García Solano · Servicio Madrileño de Salud

    I suggest to work on defining your own objectives (few) from your ethical perspective, sharing them with someone also compromised (find allies), make those objectives factible, find motivators and work day to day to reach your objectives through a plan, assesing periodically how does it go and taking care of your own and your people. Summarizing: use your mind and heart with method, and if possible, in company. Ah!!! And celebrate your little successes, to keep motivation. Good luck, Ahed, it's worthwhile and you deserve to develop your creativity anywhere.

  • Rasool Bahrampoury asked a question in HYSYS
    Which fluid package in Hysys is the best for water-ammonia mixture?

    Although exact data are available in EES, some tried packages show considerable deviation. Which package is appropriate,  or how can I have more precise results using the exact solution in the software.