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  • Can anyone guide me quantitatively in histopathological grade-scale(s) related diabetic nephropathy in animal models?

    I need some guides or protocols  related to the topic ,  included some parameters such as ; mesangial matrix expansion, glomerulosclerosis, tuft-to-capsule adhesions, hyalionosis( glomerular or tubular) , dilatation of urinary space and thickening basement membrane of bowman's capsule (light microscopy assessment)

    Mario Barac-Nieto · Kuwait University

    answers 1 and 2 should be sufficient

  • Is there any validity study of Simon Sinks' golden circle model (Why-How-What) for using in a community based research setting?

    For community based participatory research we put the 'members of the community' at the centre of the model. Adopting the golden circle model of 'Why-How-What' helps us synthesizing the policy level, procedure level, and operational level action items for identifying our research questions, methodologies, and deliverables. Extrapolation of this model into our research has been yielding greater efficacy and insight. At this level we are very interested to know about any validity analysis of this inspirational leadership model for using in research.

    Marika Ronthy · Amfora FutureDialogue AB

    I want to give you an example where you can use the three questions in an other context. We are validating a questionnaire called Leader Intelligence Questionnaire(LIQ)based on Ronthy's theory called Leader Intelligence which means there has to be a balance between the spiritual intelligence(why), emotional intelligence(how) and the rational intelligence(what).Leadership as I see it starts with the question why which has to do with vision,meaning and purpose. How has to do with relations, to my self and others and finally , what to do. Shortly a balance between being and doing. Most leaders are trained in the"doing".The employees get their energy and motivation from the "why" and "how".

  • Snehal Gite added an answer in Antioxidant Activity:
    Compounds exhibited good antioxidant activity but same compound increase the intracellular ROS level, any explanation?

    Some compound show good antioxidants activities but we treat to cancer these compounds increase the ROS levels.Explanation with some articles related to these.

    Snehal Gite · Pravin masalewale

    Antioxidants that are reducing agents can also act as pro-oxidants. For example, vitamin C has antioxidant activity when it reduces oxidizing substances such as hydrogen peroxide. However, when vitamin C reduces the metal ions that generate free radicals through the Fenton reaction.

    The chemical surrounding of antioxidant compound do decide the fate of that compound whether it will act as antioxidant or pro-oxidant

  • Has there been research to show that increasing education improves ethics in a community?

    'Students often know the right thing to do. How can schools help them to do it?

    The numbers are in and they don't look good." That was the assessment of the Josephson Institute of Ethics last October, when they conducted a survey about the moral standards of more than 20,000 middle and high school students. Almost half the young people reported stealing something from a store in the previous 12 months. In the same period, seven out of 10 cheated on an exam.
    Should we be worried? Many observers say that we should. We see evidence of more antisocial behavior than ever among our youth—a sort of divorce between personal ethics and everyday behavior.'

    Has there been research to show that with increasing education, there has been improved ethics in a community?  Can you share, give some evidence? Thanks.

    Marcel M. Lambrechts · Centre d'Ecologie Fonctionnelle et Evolutive, Montpellier, France

    Laws of rules: There are so many that people either cannot truly understand or know them during daily life? Therefore, laws of rules often start to be recalled/applied when it is too late, accepting that people behave in ignorance?

  • Voltage or current controlled device is a BJT? And what does "voltage controlled" and "current controlled" mean? Is this a property of the BJT?
    This discussion is old as the very bipolar transistor... but it is still interesting...

    In my opinion, a BJT can be controlled either by voltage or current depending on the situation. If we want a maximum gain (the case of amplifying stages), we apply a small (to be a linear device) AC voltage (e.g., ±100 mV) with an additional appropriate DC biasing voltage (e.g., 0.65 V) directly to the base-emitter junction; then we can consider the BJT as a voltage-controlled device. The problem is that the base-emitter junction, like a diode n-p junction, is not so suitable for a voltage control since it behaves as a voltage source (more precisely, as a constant-voltage nonlinear "resistor"). Figuratively speaking, there is a conflict between two constant-voltage devices connected to each other (an incorrect arrangement). The dual incorrect arrangement is if we try to inject a current into the BJT collector (the "dynamic load" odd idea).

    If we want a maximum input voltage range, we drive the BJT base-emitter junction through a resistor Rb (the picture in the attachment below); then we can consider the BJT as a current-controlled device. We may look at this arrangement from two viewpoints. First, we can think of the combination "Vin + Rb" as a simple current source that is shorted by the transistor input (the base-emitter junction acts as a current load). Second, we can think of the combination "Rb + base-emitter junction" as a transistor with a large voltage range (a voltage load).; as though the transistor has enlarged many times its input voltage range and it has transmuted into a kind of FET-:) The increased linearity will be an additional advantage...

    This is an old V-to-I technique widely used in the measurement in the past - imagine an old-fashioned analog voltmeter built by an ammeter (a movement) and a resistor connected in series. Like in the case of the BJT above, we can control a real ammeter by a small voltage (a few hundred mV). The only difference will be the linearity...

    But yet, what does "voltage controlled" and "current controlled" mean? Is this a property of the input source or of the very BJT?
    Vaibhav Bharatrao Vaijapurkar · Pune Institute Of Computer Technology

    Dear Lutz sir

    Sorry for long answer but it justifies the things you mentioned. please take some time for reading.

    If Emitter resistance is not connected then do you claim circuit doesn't work. Then hows feedback ?

    The feedback at Re exist only for AC input , for DC circuit there is no feedback (In ac analysis Capacitor acts as short circuit hence it bypasses Re but in DC it is not). As i mentioned previously it is a device property not of circuit hence no feedback

    I think Re do not decide Input impedance of circuit.please see Millers theorem for CE with un bypassed Re.I also request you to see circuits without Re ( AC and DC analysis) .

    The Early effect also says that Base width varies but significant Vbe remains constant.

    Vbe saturation or Vbe on for transistor can be 0.658V . Ok! now we will increase  till the required value (i.e 0.658V), transistor will come in action. There is some IC for set value. can we say since Vbe is set there is no further increment in IC.

    But if we change IB there is increment/ decrement in IC.

    What is this all signifies?.

  • What can explains the positive relationship between trade and relative demand for skills in developping countries?

    Many empirical studies have found strong evidence for the existence of positive relationship between trade liberalization and relative demand of skilled to unskilled employment in developing countries.

    The question that need more investigation is how to explain this positive relationship?

  • Andr� Decoster added an answer in Income Tax:
    Does anybody know of an internationally accepted measure of personal income tax progressivity?

    What I have in mind is a numeric (preferably continuous) measure of personal income tax progressivity that allows to compare countries in a consistent manner.

    Andr� Decoster · KU Leuven

    Two remarks

    1) All three measures (Kakwani, Musgrave-Thin, and Bénabou) are related; see book of Lambert 2001 for a clear exposition (Chapter 8);

    2) all mentioned measures are empirical measures, in the sense that they are applied on a given income distribution. If you calculate the measures for an unchanged tax structure, but on two income distributions which are different (or have changed), the measures will give different (or changed) numerical results. Question is; is it this what Stefan wants? If not, then he should go for local measures (again see Lambert 2001 for an overview). Only problem then is: how to aggregate the local properties of a tax schedule into one number (if this is what you are after). In general this is not evident . In specific cases it is possible (e.g. constant elasticity functions).

  • Can anyone suggest advanced studies on data mining systems for sentiment analyses and possibly cognitive approaches?

    The problem is to put together sentiment analyses and emotion recognition as the data mining system should be based on some knowledge construction with regards of the multimodal web journals. However, the system should be purely textual.

    Velina Slavova · New Bulgarian University

    Of course you are right, Pooja.

    There are several levels studied till now in sentiment analyses. The sentence level is just one of the levels. Discourse level, document level...

    General contextual level... World description level. But they are not studied.

    You are right to propose to take typographical features as possible source of the conveyed  attitude.

    I should attach the project to my question. I do it now. Thank you.

  • What is the best way to fit Circular Dichroism Data of a pH titration?

    Hi to all,U of a protein in order to monitor its secondary  structure changes by means of Far-UV Far- Circular Dichroism.

    I'd like to extrapolate thermodynamic Data. For example the free energy of unfolding of the protein.

    I have plotted the pH variation against the molar ellipticity at a certain wavelength, and I got a sigmoid-like distribution of my data.

    What kind of function would you use to interpolate these data?


    Giovanni Colonna · Second University of Naples, Naples, Italy

    Typically transitions due to the pH in globular proteins do not lead to a complete unfolding. In the acidic range, they are due to the protonation of residues as his, glu and asp. The sigmoidal transition that is observed in far UV CD is often the sum of the various transitions of the local structural regions in which are contained the protonated residues. If a transition covers more than two pH units is indicative of multiple transitions. In general, it is good to follow more than one instrumental observable (eg. maximum shift of trp fluorescence, fluorescence polarization, etc.). In this case the curves detected by the different observables should be superimposed for a single coincident structural transition, but you have to make sure that the protein, to its lower pH of the transition (at the bottom of the sigmoid), is not further denaturabile with increasing concentrations of GdnHCl. If there is another sigmoidal denaturation, this means that we are denaturing also the residual structure. In general, an evaluation of thermodynamics with a simpler approach, is the one that uses the two-state model. If there are intermediates, the thermodynamic analysis is more complicated. 

  • Is anyone interested in investigating the kinesthetic and somesthetic sense through proprioceptive control?

    Until now we have investigated the arm proprioceptive control in volleyball players - female, but we intend to develop our researches in enrolled patients in rehabilitation programs ( i.e. post stroke ).

    Caroline I E Renner · University of Leipzig

    Hello Nicolae,

    we are very interested in somatosensory deficits and the associated fine motor deficits in patients after stroke, as we work at a neurorehabilitation center .

    Could you explain your device more in detail?

    Happy new year,


  • Prabhakar Purushothaman added an answer in Military:
    Expenditure on militity across the world is year by year increasing too much, will all these expencese will create good cause?

    As we know that in order to protect the country military forces is required and therefore it is must for any nation to strengthen their military forces but in recent years as the threats are going on increasing the expenses made on the military forces are getting increased across the world will this result in good cause instead if every country across the world starts a separate wing and spend on it for spreading peace then what would be the result kindly share your view.

    Prabhakar Purushothaman · UCAM Pvt Ltd, Bangalore, India

    Thank you Dr. Sarwan Kumar Dubey for sharing your view  I too feel if same money is spent for spreading peace might have given great result,

    When some asks a question who and all or which organizations and all spreading peace in full fledged in your country ?

    I think I have no answers this situations should change

  • Dmitry Busko added an answer in Phosphorescence:
    Can we use a fluorescent complex as a reference when we want to determine the quantum yield of a phosphorescent complex?

    I have some phosphorescent complexes and I want to calculate their quantum yield with relative method. Finding a good reference is important for me and I don't know is it important that the reference is fluorescent or phosphorescent? or just its abs.  and em. Is wavelength important?

    thank you

    Dmitry Busko · Max Planck Institute for Polymer Research

    There is nice review (The best up to now, I would say) about quantum yield measurements:

    But briefly:
    1. take a reliable standard in appropriate conditions (aerated or not solvent), which solvent, which concentration. Some dyes, still used by many people like a standards, are strongly dependent on concentration, temperature and presence of oxygen. But, in general, like Wiesley R Brown wrote, it does not matter is it fluorescent or phosphorescent standard.
    2. The spectra of standard and a measured dye should be in the same wavelength region. It will minimize the error.
    3. Using same excitation wavelength for both dyes (if possible, of course) will just save you a time, but you can also use different wavelengths - just use the appropriate equation for calculation of QY.

  • Rafael J. Caro added an answer in Disaster Medicine:
    Does anyone have information about disaster medicine/management education of undergraduates in local medical schools?

    I am trying to get a picture on existing programs (voluntary or obligatory) in DM education on medical schools.

    Rafael J. Caro · Tecnatom

    Dear Luc,

    In my specific field there is a good reference from IAEA;

     Generic procedures for medical response during a nuclear or radiological emergency

    It can be found at:


    If you are interested in this kind of things, more information can be found at IAEA website, or I can provide you more links.



  • What is the difference between Thermal supercooling and Constitutional supercooling in the solidification of pure metals and alloys?

    This is in the topic of Solidification of Metals. I just want a solid explanation on this one. Please help.

    Jeremy S Robinson · University of Limerick

    The book "Phase Transformations in Metals and Alloys" by Porter and Easterling gives a a good explanation of what happens at the solid liquid interface during solidification.

  • What is the average (max-min) partial arterial oxygene pressure during hyperbaric oxygene therapy?

    What is the average (max-min) partial arterial oxygene pressure during hyperbaric oxygene therapy?

  • Wan Zubaidie added an answer in Biomaterials:
    How can I extract the fibers from the leaves mechanically?
    How can I extract the fibers from the leaves mechanically?
    Wan Zubaidie · Universiti Tun Hussein Onn Malaysia

    dear sir..

    thanks for sharing the information..

    it's quite nice since im new in this field of work.

    thanks for all of your discussion.

  • Can anyone suggest a practical application of lipase?

    Please  suggest an application of microbial lipase that could be carried out in the lab. 

    Mansour Ghaffari-Moghaddam · Zabol University

    You can do some hydrolysis reactions by lipase. I attached a review paper. Please see it.  

  • Sunil M Patange added an answer in Ferrites:
    What is the effect of domain wall motion on Magnetization of Ferrites?

    I'm wondering whether domain walls hinder, increase or decrease magnetization?

    Sunil M Patange · S.K.M. Gunjoti

    If domain wall increases  the magnetization will be decreases the size wall is affect to demagnetization of ferrites.

  • Sarwan Kumar Dubey added an answer in Language Arts:
    Are there any theories that would be useful for researching the relationship between art and language?

    I am interested in doing a research about the effect and role of language in art mainly concentrating on modern/contemporary Asian art (particularly Mainland Chinese and Taiwanese). I would like to look at this question more from the perspective of linguistics than the fine arts one. Any recommendations, suggestions or references regarding "art and language/text" topic would be very appreciated. 

    Sarwan Kumar Dubey · Central Soil and Water Conservation Research and Training Institute

    Hi Dear following article will be helpful for you.


  • Avinash Acharya added an answer in MATLAB:
    Can we form an image from a given dataset in matlab? if yes, then how?

    There is a dataset given by Villanova University on radar imaging. I need to know how I can form an image from that given dataset.

    Avinash Acharya · Homi Bhabha National Institute

    you can save a data set in .txt file and then can generate a surface 3 d plot using surf function in matlab.

    sample code 

    saved file a.txt

    the a=load('a.txt');

    then surf (a); view (3); shading interp;

    will give a 3 d plot.

  • Pankaj Dey added an answer in Time Series:
    What are the conditions of using simple water balance equation?

    Simple water balance equation, P = E + Q, where change in storage can be considered negligible. Apart from having sufficiently long time series of observation of hydrologic variables like streamflow (Q), meteorolgical variables like (P = precipitation, E = evapotranspiration) for a particular time series, what are the other criteria that must be needed to be satisfied to use this simple water balance equation for study of impact of climate change on water resources?

    Pankaj Dey · IIT Kharagpur

    I am not clear how to justify groundwater, whether the baseflow component should be included in the discharge

  • Is there any simple and PCR-Based method for Fragile X syn Testing?

    im working about fragile X syndrome by PCR but cannt get band, who know what ido?//////////

    Dominique Liger · Université Paris-Sud 11

    Hi there,

    If you don't get any band, you have a problem with DNA template or/and PCR. First check the template quality by running a PCR using a different set of primers for which you know the expected result. If it's working, it means there is something wrong with your X fragile diagnosis primers. If it's not working, your DNA sample is bad and you will have to work on improve its quality.

  • Gautam Sagar asked a question in Communication:
    Why uplink frequency is higher in satelite communication?

    insatelite uplink frequency is higher than downlink frequency

  • Michael Franke added an answer in Semantics:
    Should the root/epistemic distinction be made on semantic or pragmatic grounds?
    I'm beginning to think that this distinction is not as clear-cut as it has traditionally been taken for granted. Consider the following example: "She may like this one" (uttered by a friend who is helping you find a dress for your girlfriend). Many would say that this is a case of epistemic modality (no speaker's commitment to the truth of the modalized proposition). However, in this context, the utterance of "She may like this one" counts as a suggestion, this notion falling, in my view, within the domain of deontic modality.
    Michael Franke · University of Tuebingen

    This is a good question. Like you suggested as well, I think that it would be best to keep the semantics lean, in the sense of sticking with the idea that "may" in your example is just epistemic modality. This is because there is a straightforward pragmatic explanation for why an epistemic statement in this context would naturally serve to make a suggestion.

    If you are interested, this case is dealt with in a paper of mine called "Now that you mention it: Awareness dynamics in discourse and decisions" (you can find it here on ResearchGate). The idea is that generally epistemic possibility statements are very weak, and therefore require pragmatic back-up anyway. If I say "there might be an alien invasion", there is a sense in which this is true, but certainly utterly irrelevant for any (sane) decision making process. If we reverse this, this means that epistemic possibility statements come with a pragmatic requirement of being practically relevant: raising only those possibilities to joint awareness that may be helpful for the practical issue that is at stake (like in your case, finding a dress).

  • How to find the homogenity and percentage of reinforcement present in the Aluminium Silicon Carbide metal matrix composite ?

    Homogeneity and Percentage of Reinforcement present in Al-SiC metal matrix composite.

    Alexander Tsouknidas · Aristotle University of Thessaloniki

    I think the most accurate way is to scan the samples with micro Computed Tomography (μCT). Aluminium would give a different grey spectrum which could be completely segmented from the MMC, thus allowing you to visually check the distribution homogeneity. If you want to do a quantitative analysis of the homogeneity then you will have to use additional software on the μCT reconstructed sample (i.e. ImageJ or Avizo Fire).

  • Xia Yinxiang asked a question in Microscope:
    Dose anybody know about the integral pickup system?

    dose anybody know about the integral pickup system in the light field microscope and how it works

  • Grzegorz Dybowski added an answer in Innovation:
    Is there any research on services to agriculture?

    I am interested in theoretical frameworks to understand why services to agriculture are increasing and what role services play in improving the competitiveness of small farmers.

    I look to different types of services: operational services (machinery,..) and also knowledge-based services (advice, extension...).

    Grzegorz Dybowski · Instytut Ekonomiki Rolnictwa i Gospodarki Żywnościowej

    Market analyses on production sources for agriculture including basic services have been prepared twice a year in the Institute of Agricultural and Food E$conomics in Warsaw, Poland for over twenty years. Summary is in English. You ma find them interesting. Regards,


  • Parham Kabirifar added an answer in Cold Rolling:
    Does anyone know why (hot or cold)rolling of TiNiCu shape memory alloys with over 10 atomic percnt Cu is not possible?

    I work on this project and can't hot roll the Ti50-Ni35-Cu15 at%  alloy. during hot rolling in 900'C the sample were cracked. Can strain rate of rolling machine have a role in this phenomena?


    Parham Kabirifar · The Hong Kong University of Science and Technology

    as far as i am concerned SMA's are definitely rate dependant, so the rate is effective. by the way do you reheat your specimen after each pass? the temperature drop during the passes could be another issue.

  • Xia Yinxiang asked a question in Integral Imaging:
    Dose anybody know about the Real-time integral imaging system for light field microscopy ?

    recently i have been learning about the light field microscope mow there is a kind of LFM called Real-time integral imaging system for light field microscopy does anybody know about the integral pickup system