ResearchGate Q&A lets scientists and researchers exchange questions and answers relating to their research expertise, including areas such as techniques and methodologies.

Browse by research topic to find out what others in your field are discussing.

Browse Topics

  • Nicholas Chileshe added an answer in IT services:
    Is there a SERVQUAL questionnaire that assessed the perceived and expected clinical students?

    I'm going to investigate the perceptions and expectations of clinical students  from educational services and i  in need a standardized questionnaire based on SERVQUAL model

    Nicholas Chileshe · University of South Australia

    Dear Omid,

    The following two cross-sectional studies might be of help. The first study collected data from 135 paramedical students whereas; the second was undertaken within the context of medical education using a sample of 384 students of medical sciences. Depending on the settings, you be able to adapt some of the items as used within the SERVQUAL to suit the clinical students.

    Bahadori, M., Sadeghifar, J., Nejati, M., Hamouzadeh, P. and Hakimzadeh, M. (2011), Service by the SERVQUAL model: Viewpoint of paramedical students at Tehran University of Medical Science, Technics Technologies Education Management, Vol. 6, No. 4, pp. 1058-1065

    Bahadori, M., Mousavi, S.M., Sadeghifar, J. and Haghi, M. (2013), Reliability and performance of SERVQUAL survey in evaluating quality of medical educational services, International Journal of Hospital Research, Vol. 1, No. 1, pp. 39-44.

    These two studies might provide you with directions for obtaining the standardized questionnaire that you seek.

    All the best with your research.


  • Ajay Singh added an answer in Groundwater Quality:
    What is the best option for manging the environmental problem of seawater intrusion in coastal areas?

    The seawater intrusion is a widespread environmental problem of coastal aquifers where more than two third of the world’s population lives. The indiscriminate and unplanned groundwater withdrawal for fulfilling the growing freshwater needs of coastal regions causes this problem. Seawater intrusion is one of the major causes of groundwater quality degradation because mixing even a small quantity of 2-3% saltwater makes the groundwater unsuitable for domestic, agricultural, and industrial uses. What is the best way of managing this problem?

    Your response is very much appreciated.

    Best regards,

    Ajay Singh · IIT Kharagpur

    Dear Golam,

    Thank you for providing this nice reply.

    Bets regards,


  • Ade Olaiya added an answer in Health Research:
    What are the diet practices of researchers; are they based on health research?

    At a time when viruses are mutating, and vaccines are still being tested, and new diseases causing deaths; what are the diet practices of researchers and scientists. Are our practices in line with our knowledge, and current health research?

    Ade Olaiya · University of the West of England, Bristol

    For this researcher it should be ... less protein and carbs, ... more fruit and exercise based on health research ... not always easy to stick the course though.

  • Haotong Xu added an answer in Clinical Neurology:
    Focal supratentorial cerebral edema: differential diagnosis?

    Dear Colleagues, there is a 67 year old female patient with focal edema of frontal, parietal and temporal right side cerebral lobes, with slight dislocation of median brain structures on MRI, no enhancing contrast regions. Sick for 1,5 months, symptoms: fatigue, slight ataxia, slow thinking, no headache. Exam: slowliness of all types actions. No signs of compromised immunological status, no signs of infections. MRI performed twice: 25 september and 20 october, looks almost the same. Some ideas? thank you!

    Haotong Xu · North Sichuan Medical College

    Hi, Olga Schiopu! As aforementioned, the MRI with contrast will provide more information to us. If you're convenient, I suggest you to send the DICOM format of the MRI images, including the MRI images with contrast to me. I have the imaging software to deal with the images, especially to alternate the window width and the window level of the MRI image, maybe some underlying information in MRI images will be manifested to us. Moreover, the additional medical history of this patient will be useful.

  • Primary smooth muscle cells culture contaminated with fibroblasts.
    I am isolating smooth muscle cells form abdominal aortic aneurysm tissue. In brief I cut obtained tissue into small pieces and digest it overnight. The cells grow very well in M199 medium with 10% FSC and antibiotics, however, after three passages I get more and more fibroblasts. Can anyone advice me how to diminish their population? As I know that fibroblast are easier detached I tried to trypsinize cells for one minute, then get rid of the medium and again use trypsine to detached the rest of the cells. This brought some benefits but maybe you have some other ideas. Many thanks for your help!
    Aleksandra Piechota-Polanczyk · Medical University of Łódź

    Thank you guys!

  • Kittipong Tripetch asked a question in Circuits:
    Can you give the best mass product in the field of biomedical circuit and systems?

    Wouter Serdjin 

  • Israel navarro quintero asked a question in Weapons:
    ¿I could you please leave me some articles about biological weapons?

    I need to make a presentation at the University on biological weapons and their possible consequences, thanks

  • What is the main difference between performance measurement and performance evaluation?
    Are such tools like balanced scorecard and key performance indicators tools of P. Measurement or P. Evaluation?
    Marie Florence Desir Pierre · Université Quisqueya

    Performance is measured For the full activities of the company`s from financial ratios, but there are also non-financial measures that are particularly depend to managers who now speak in concrete terms representatives of features attractive to.
    While  performance evaluation is an effective and regular process helping the development of employees. It is an engagement process to attempt objective aware of the year.  At the end of the exercice, a meeting allows you to point through the objectives on the performance of  the employee.

  • Bahman Mohmmadi added an answer in CST:
    Missing link between phased array and adaptive arrays ?

    I have spent a lot of time with Matlab codes capable of designing electronically scanned parasitic arrays with the help of CST MWS. I am able to focus the beam in a desired direction by changing the phase shifts of the different elements.

    Now the question is, how do I design an adaptive array using Matlab where the same antenna is capable of recognizing an incoming signal and estimating the location of the emitter ?

    Any suggestions are much appreciated.

    Bahman Mohmmadi · Urmia University

    We can use beam forming theory, And Adaptive Filter for estimating the location of the emitter.

    Adaptive Signal Processing by Bernard Widrow

  • Tamer Madi added an answer in Survey Analysis:
    Is it correct to map the "means" into "equal intervals" to facilitate the interpretation of the survey results?

    I saw some researchers who used this formula: (n-1) / n, where n is the maximum number in the used scale. For example in five-point Likert scale, n is equal 5. So, the interval size can be calculated as 0.80. I just need a confirmation or precise evidence 

    Tamer Madi · Universiti Utara Malaysia

    Thanks for all. Tineke, the reason that I want to perform a numerical transformation to my survey data is "most of the mean values are lying around 3 so I can not interpret the results".

    My study is descriptive and I have used a simple likert-scale from 1 to 5.

    Hope I get a simple solution

    Regards for all

  • Gt Vinodhini added an answer in Voltage Stability:
    Does Neural Networks based voltage stability assessment has any drawbacks?

    In terms of accuracy, and training requirement for different operating conditions.

    Gt Vinodhini · Annamalai University

    The major drawback is in design phase i.e to.determine the optimal number of nodes, hidden layers, sigmoid function, etc

  • In your institution, what are the strategies and/or approaches in generating funds for your research projects?

    The common problem being encountered by universities and other institutions in developing countries is the lack of funds to conduct research projects.  Financial deficiency results to lack of incentive for researchers, absence of high-end technologies, instruments and materials for laboratory works as well as poor dissemination of outputs.  As a consequence of a poor monetary support, research outputs seldom find its way to globally-recognized and standard scholarly journals.  Thus, without a reasonable amount of funds, research has become an exercise of futility and mediocrity.

    Roland Iosif Moraru · University of Petrosani

    Hello Gerry

    Funding for research comes in my University (and this stays valid for most Romanian Universities) from;

    • Horizon 2020-European Programme
    • Joint Research Programs - bilateral, funded by government
    • Grants with industry for answering company's needs
  • Ajay Bajracharya added an answer in ArcSWAT:
    Error while delineating watershed in SWAT?

    I am getting an error: "no features found. possibly an empty feature class." while delineating watershed in SWAT from DEM. I am using ARCGIS 10.1 and ARCSWAT version 2012 .

    sometimes the error occur as :

    " the watershed with grid code does not have an outlet within it . This is  likely because the outlet falls on a edge of the watershed boundary."  for the same process...

    Ajay Bajracharya · Asian Institute of Technology

    I have tried both the ASTER and SRTM DEM. How to check the DEM data??

  • How can we implement haptic feedback surgical instruments in practice?
    I have a R&D company; the first haptic feedback laparoscopic instruments;
    Soroush Sadeghnejad · Amirkabir University of Technology

    Please take a look at this website, it can help you more in finding good sensors.

  • Protein sequence of Minnelide or Triptolide?

    I have searched in ExPASy about the sequence of  Minnelide or Triptolide. Can any one suggest where I can find the protein sequence of those two. And please let me know, if genome sequence of Tripterygium wilfordii is available.



    Nathaniel Weygant · University of Oklahoma Health Sciences Center

    Minnelide and Triptolide are small-molecules - not proteins. 

  • Duy Võ asked a question in Mathlab:
    How to design Quaternion Estimation (QUEST) algorithm?

    QUEST is popular in Kalman Filter design. As some publication's result, this help reducing the computational effort. The Input includes accelerration and gyroscope and the output is in quaternion term.

    I'm trying read and understand how it work. Most of what I read doesn't mention how to implement this algorithm. Is there any easy approach in particular INS-IMU design like embedded code, Mathlab, document?

  • Alejandro R. Silva added an answer in Geopolitics:
    Are gas and oil, and in the future drinking water blessing or a curse of modern geopolitical expansion of globalism?

    The development of civilization shows that for economic growth and technological development needs more and more energy ....

    In this context it should be noted that the main geopolitical disputes and conflicts are related to the richest and the most profitable reserves of future world oil production and natural gas, and that conflicts in the guise of a clash of civilizations are in fact conflicts over energy resources and in the future over drinking water...

    Alejandro R. Silva · University of Buenos Aires

    Dear Darko,

    What an interesting question!

    During the 90s this debate took place in Argentina, regarding both Energy Reserves and Water Reserves. Patagonia is a vast region, with lots of lakes and glaciers on the West and semi desert lands on the central and eastern part. The same happens on the Northeastern Region, with the Parana and Uruguay River. Patagonia is also oil and gas rich.

    Brazil is Water rich and recently discovered oil reserves makes it Energy rich too.

    Water and Energy reserves are a BLESSING, without any doubt, what is a CURSE is how governments or societies manage these resources. The institutional environment is a key element to understand what societies do with their resources.

    Venezuela holds the largest oil and gas proven reserves (http://www.eia.gov/countries/country-data.cfm?fips=ve) and the people struggle to survive with an insufficient supply of milk, flour, sugar, chicken, cheese, beef and even toilette paper! (http://www.infobae.com/2014/02/09/1542617-los-10-productos-que-mas-escasean-venezuela).

    On the other hand Israel holds almost no natural resources and achieves very important indicators in the field of technological innovation, science, social welfare and education.  The same stands for Singapore and Ireland.

    I do not see any threat to Energy reserves in USA, CANADA, RUSSIA, VENEZUELA or Argentina (2nd largest shale oil & gas reserves).

    I do see many conflicts in regions where the "institutional environment" is weak, with outstanding political instability, and with unsatisfied consumption and political demands by their citizens. It happens that some of these countries are energy rich, but some others are not.

    If a country has Energy and Water reserves, and an educated and people conscious ruling class, with the rule of law, independence of Powers, Enforcement and accountability; this country should fear no threat to its resources.

    Knowledge is the fifth factor of production, apart from Land, Labour, Capital and Entrepreneur. To organize a society you need Institutions, and ultimately these are a "form of knowledge", just as technology or science. Organization and Management are knowledge too. So in the end, "competitive advantages" lie in the property and use of knowledge. If Knowledge is included in the "Theory of Comparative Advantages", you'll find a clear explanation of why some societies succeed and others fail.

    I hope this helps to answer your question.

    Best regards,

    PS: "Culture Matters. How values shape human progress" Edited by Lawrence Harrison and Samuel Huntington, is a very interesting book that explains human progress from an institutional stand point.

  • Roland Iosif Moraru added an answer in DAD:
    How to maintain or improve the teenagers’ relations with their fathers?

    Dear Professors/RG members/friends,

    In India most of the teen agers, when they join the colleges they stop talking to their fathers freely. They mostly approach the father through their mothers. This leads to the psychological depression of the fathers and since they don’t know how to correct this problem, behaves very strictly with their sons/daughters worsening the situation still more.
    Fathering a little son/daughter who wants nothing so much as to be "just like my dad" is much easier than fathering an adolescent son/daughter who wants to follow his/she own agenda and be his/her own man/woman.

    Dr. Shanmugasudnaram P

    Roland Iosif Moraru · University of Petrosani

    Dear Shafiq and Mahfuz

    I agree with you (I am my son's best friend), that we have to be friends, as best as we can. But, sometimes friendship isn't enough. Adolescents are rebel. That's part of their job. But if you can hang in there and keep the love alive, things will work out.

    As one psychologist put it with a gentle laugh, "The moment of truth comes when you realize your son has more testosterone than you do."

  • Vernon Ireland added an answer in MCG:
    Kevin .McG. Adams, Systems principles: foundation for SoSE Methodology

    Is paper available?

    Vernon Ireland · University of Adelaide

    Kevin .McG. Adams, Systems principles: foundation for SoSE Methodology

    Is this paper available?

  • Which is the best (additional) training model for surgery residents?

    Let’s imagine that there is only one available option regarding hands-on training in laparoscopic and/or robotic surgery for residents, besides assisting at surgical operations. The choices are as follows:

    1. surgery simulation using high-end virtual reality software or
    2. animal models as part of licensed live-tissue research protocols.

    Which one would you choose and why?

    It would be interesting to explore the perspective of professionals from different scientific fields (i.e. residents, board certified surgeons, professors, computer engineers, animal specialists or even financial analysts etc).

    *Evidence-based answers with literature references will be appreciated.

    Soroush Sadeghnejad · Amirkabir University of Technology

    I think for the first step, using simulators sense good. By using this way you can anatomically learn your students well, then you can switch to the animal case or also to the real surgeries. 

  • Sabita Ghimire added an answer in Polyketide:
    What is the significance of extracting polyketide gene of actinomycetes? Isn't it obvious they have it?

    I was asked this question and couldn't answer. I am going to see antibacterial activity of actinomycetes isolated from soil. And a part of research is PCR and detection of polyketide gene. Please enlighten me the significance here.

    Sabita Ghimire · Tribhuvan University

    Thank you both for kind and helpful responses.

  • Louis Brassard added an answer in Philosophy:
    Can ethics be measured objectively?
    Ethics, ethical committee, ethical approval and other ethical related words are extensively used on Researchgate and other places. How to define and measure ethics in objective bases?


    That defintion is not that far from the third defintions you gave from the webster.

    I will do some digging. And i will elaborate the link with the core belief defintion.

    I do not denied the possibility of knowledge.  I simply include all knowledge into belief.  Knowledge is of different type corresponding to the different type of belief.

    '' "transcendence." This is quite the opposite of the scientific approach. and implies such things as higher powers, transcendental states, and supernatural gods. ''

    Science is about reaching reality which is transcendant to any form of knowledge and science in particular.  Science is a naturalistic type of belief system which means that there is no two realms : a super-natural realm and a natural realm.  Everything has to be natural but what is the ultimate reality of nature is beyond science.  I can go on and on but the point I am making is that science is a believe system but it is one with a lot of specific requirements.  Science in the west emerged from philosophical form of religion.  It is the same in the East but in the east philosophy until today is consider part of the religion while in the west it stopped to be considered that way in the modern time and science splitted from philosophy a bit later.  This is the big problem we have, a lot of scientist think they do not do philosophy and that science is not oppose to religion.  It is just a big confusion we have.  

  • Bhagya Deepachandi added an answer in Immunoassay:
    Alternative methods for western blotting?

    I want to analyze immuno-dominant antigens of parasites. I extract crude protein and want to check it's immunogenicity using an immunoassay. And I want to find the size of each antigen? is there alternative methods to western blotting to do this?

    Bhagya Deepachandi · Faculty of Medicine, University of Colombo, Sri Lanka

    @ Sereno, is there any way to do immunoprecipitation without using beads?

  • How do entrepreneurs behave when they sell product, service or entrepreneurial ability in a face-to-face selling transaction?

    Is this an extension of under researched entrepreneurial behavior (EB) topic? Has the field of entrepreneurship ignored or restricted knowledge about this very important construct? Current studies are rather limited and focus mainly on EB sub-variables like innovativeness, opportunism , change orientation and risk taking. The summary question is : Is selling behavior one of the core entrepreneurial behavior?

    Debi S. Saini · Management Development Institute Gurgaon

    Like every other seller, they indulge in sales talk--some do in a more sophisticated way, but others do it in a typical salesperson way, and have in mind mainly the protection of their interests. Those who want to safeguard and build their brand for the future keep in mind their long-term interest, of course. 

  • What is the maximum weight that a human chest can bare?
    We are working on an assistive robotic system for elderly. We need to know maximum weight that a human chest can bare. It would be grateful if I get links to associated literature.
    Soroush Sadeghnejad · Amirkabir University of Technology

    I think in this study you can refer also to CPR procedures. They will give you some valuable results too.

  • What is the difference between load flow analysis and state estimation in power system analysis?

    May you please state the difference

    B. Rajanarayan Prusty · National Institute of Technology Karnataka

    Dear Gasim 

    Power system monitoring and control in real time can be done with the help of state estimator (SE) program. SE periodically computes an estimate of the operating state of the sub network of interest there by produces an approximate model of the true operating state of the system. Where as load flow analysis is used in contingency analysis for each contingency case to obtain complete and accurate solution of complex bus voltages at system buses. 

  • Rajat Pradhan added an answer in Electromagnetism:
    What is the significance of the Poynting vector in a static electromagnetic field?
    In an electromagnetic field the flow of energy is given by the Poynting vector. For an electromagnetic wave, this vector is in the direction of propagation and accounts for radiation pressure. However, in a static electromagnetic field the Poynting vector can of course be non-zero. It's not easy to understand how there can be a 'flow' of energy in a static situation. Please discuss.
    Rajat Pradhan · Utkal University

    Dear Eric and others on this thread,

    The following very interesting answer of mine  I put here from a related thread started by me. Hopefully you'll all enjoy the argument.

    I want to make the following rather pedestrian observation:

    We know that the Electric field can accelerate a charge. Now, what can possibly accelerate something i.e change the velocityof something? Ans: A force i.e. a quantity that can change momentum .

    How can a force lead to a change in momentum unless it itself is endowed with the ability to suck in or impart momentum?

    Thus the force or the field must be a storehouse of momentum that can act as a source as well as a sink of momentum.

    It means that the static electric field also (not just the Poynting vector) must carry momentum.

    For that matter, any force field must be such a storehouse of momentum, since it can give only momentum to another and that is what it has and that is what it does i.e. change momentum.

    We may call it the potential form of momentum, to distinguish it from the kinetic form (massx velocity) that we are familiar with.



  • Presence of Heavy elements on the Sun

    I have read that according to "stellar nucleosynthesis" process heavy elements can only formed when star have used all its hydrogen, and it then further starts fusion of heavier elements (like He,Li,C,N,O  etc.).

    Our Sun still has around 75% of hydrogen then how other heavy elements (like Fe,Ni,Ca,C,N,O,Si,Su,K etc.) are present in the Sun (specially in photosphere and Corona)

    M.A. Padmanabha Rao · Defence Laboratory, Jodhpur, Rajasthan, India


    Please go through the excellent article below.

    Nature’s Nuclear Reactors: The 2-Billion-Year-Old Natural Fission Reactors in Gabon, Western Africa

    By Evelyn Mervine | July 13, 2011 | Comments33


    Fortunately, the nuclear officials and scientists eventually remembered the old publications of Kuroda and others, and they soon realized that the anomalous uranium from Gabon provided evidence of something extraordinary—the first natural nuclear reactor ever discovered. The uranium ore was depleted in uranium-235 because two billion years ago some of that uranium-235 had been used up in a natural nuclear reactor. Eventually, sixteen natural nuclear reactors were discovered in uranium mines at Oklo [Figure 1]. An additional seventeenth natural nuclear reactor was also discovered at Bangombé, located about 30 km to the southeast of Oklo.

    Also please peruse the comment by daosipc:

    What today’s scientific and technological community has discovered is sufficient to change our present textbooks. Once humankind’s conventional mentalities form a systematic way of working and thinking, new ideas are very difficult to accept. When the truth emerges, people do not dare to accept it and instinctively reject it. Due to the influence of traditional conventions, no one today has systematically compiled such findings. Thus, human concepts always lag behind developments. Once you speak of these things, there will be people who call them superstitious and reject them—despite their already having been discovered. They are just not yet publicized widely.

  • Zhiqing He added an answer in Pipetting:
    Does anyone run 10uL qPCR reactions?

    I use Bio-Rad's SYBR Green Master Mix for my qPCR work which, according to the manufacturer's instructions calls for a 50uL reaction volume. I use 20uL on a regular basis without any problems. As I am running a lot of qPCR in the future and looking for ways to save some money, I was wondering if it's realistically possible to use a 10uL reaction volume and achieve the same results in terms of well-to-well variability. My main concern is the inevitable increase in pipet ting error as the reaction volume decreases. 

    So, does anyone use 10uL qPCR reaction volumes? Have you ever had any issues?

    Zhiqing He · Second Military Medical University, Shanghai

    We chose 10ul to do the qPCR not only to save the cost but also with good results, and you can try bio-rad iq SYBR Green regent or taqman regent from life corpration.