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  • Eddie Seva See added an answer in Statistical Inference:
    You can make statistical inference with a N equal or lower than 5?

    By theory he knew that within the assumptions to perform a statistical parametric or nonparametric be a minimum of 5 is required.

    Eddie Seva See · Bicol University

    There are tests of significance that allow sample sizes less than 5. You can check this is out with the formula for the degrees of freedom. In t test of r for instance, you can have at least 3. The trouble with this is that because of the very small sample size, the result will most likely be "insignificant".

  • Bernd Schmeikal added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Bernd Schmeikal · University of Vienna

    Greece should have said "no" and it said "no". This is historically, sociologically and politically consistent. But the landlord of "Upper Austria" (Pühringer) proclaimed that Alexis Zipras acted "irresponsible". Pü is the one who built his house on power, 'religion' and fear and seems to gain influence in the ORF and on the Broadcasting coverage. This man has no idea of Greek people and none of greek history either. He is but an angry, rich old man. And it is always the rich and fearful - even in Greece - who say "yes" to corruption and compromise. They will always want to let the poor pay the bills. 

  • Shilendra Kumar Sharma asked a question in Materials:
    What are the applications of direct bandgap materials and indirect bandgap materials ?

    Which type of materials are more useful direct/indirect bandgap materials or it depends on applications ?

  • Eddie Seva See added an answer in Basic Statistical Methods:
    How can I compare variables between 2 samples which have different number of participants?

    I conducted an experiment and i want to examine and compare the differences between my experiment group and my control group, but my control group is 1/3 of the experimental group. I thought of using independent samples t-tests but in spss it asks for the grouping variable which confuses me.

    Your help is appreciated.

    Eddie Seva See · Bicol University

    Strictly speaking you must go back to your experiment because your data are incomplete. Your design is for "paired" samples, and as the word connotes you must have both pre-test and post-test data for each pair. The incompleteness in your data is manifested by SPSS's comment. 

  • Subir Kumar Sen asked a question in Disparities:
    Can anyone please tell me how to get data regarding availability of infrastructure across the states during 1951-2011 ?

    Presently, I am working on regional disparity in availability of infrastructure across the state. Can anyone please tell me how to get data regarding availability of infrastructure across the states during 1951-2011 ?

  • Ángela Cruz asked a question in Business Administration:
    Can you suggest bibliography about the communication classes in the MBA level at Latinamerica?

    Material about the relationship between communication classes at business schools and the work life. Papers on academic literacy in the business administration area. 

    Thank you so much!

  • Sergei A. Ostroumov added an answer in Bibliometrics:
    Is citation rate an objective measure of merit of the scientific publication?

    This question is not that simple. Tags: metrics, value of scientific publications, articles, papers, evaluation, bibliometric information, citations, 

    Sergei A. Ostroumov · Lomonosov Moscow State University

    Ramon, thank you but in what you said I read two answers: both yes and no!

  • Stephan Michael Young added an answer in MCNP:
    How can we calculate the efficiency of a moderator using MCNP?

    We are considering HDPe as a moderator.

    Stephan Michael Young · University of Missouri - Kansas City

    I'm assuming you already have MCNP and know what geometry you need and what you need to calculate. 

    The documentation for MCNP can be kind of overwhelming when you're just beginning. Ken Shultis from Kansas State wrote a really good primer for MCNP that you can use to get started (link attached). 

  • Eddie Seva See added an answer in Hypothesis Testing:
    Can we use a case study research on an individual organization to test hypothesis?

    Can we use a case study research on an individual organization to test hypothesis?

    Eddie Seva See · Bicol University

    It depends on the type of hypothesis you have If it pertains to a hypothesis that is to be answered by "statistical significance of difference or relationship", generally it cannot be applied to a qualitative case study because of issues on absence of probability sample.

  • Hazim Hashim Tahir added an answer in Curiosity:
    What, in your opininon, should be the attributes of THE PERFECT SCIENTIST ?

    Is curiosity more important than Intelligence?

    Is Intelligence more important than Wisdom?

    Is wisdom more important than knowledge?

    Is «open-mindness» the secret?

    Does reputation play a role?

    Hazim Hashim Tahir · Ministry of Science and Technology, Iraq

    Dear Colleagues,

    Good Day,

    "Characteristics of Highly Able Science Students. This list consists of examples of possible indicators of potential. Few students will exhibit all characterisitics and these characteristics can emerge at different times, in the study of different topics, and as the child develops cognitively, socio-emotionally, and physically. For a student to be considered highly able, these characteristics should be inherent to the student and not a result of outside guidance or intervention.

    A highly able science student independently:

    • demonstrates an intense level of curiosity in science.
    • makes intuitive leaps in solving science problems.
    • demonstrates extensive knowledge base in science and is able to relate that knowledge base to new problems and topics.
    • demonstrates unusually high levels of motivation and/or concentration.
    • demonstrates the ability to integrate information and concepts into existing knowledge base.
    • possesses a good memory.
    • persists in the pursuit of science knowledge or solving a problem.
    • comprehends abstract concepts beyond age level expectations.
    • sees connections between science and other disciplines.
    • uses mathematics to understand, define, and /or solve problems.
    • makes generalizations and assumptions based on data.
    • supports thinking with logical reasoning.
    • reasons analytically, deductively, and inductively, and is able to reverse the reasoning process and to switch methods easily and in a systematic manner.
    • views problems in a holistic manner.
    • shows confidence in the use of science processes and a willingness to take risks in advancing scientific explanations and posing questions.
    • understands and applies advanced scientific vocabulary.
    • evaluates experimental results in light of the original problem."

    Please, see the following interesting articles related to the subject: 

  • Pawan Kumar added an answer in Statistical Modeling:
    Why is Nakagami-m fading channel a good in practice in place of Rayleigh fading ?

    I don't know my question is correct or not ?

    Pawan Kumar · Indian Institute of Technology Guwahati

    Nakagami-m distribution is a generalized way to model small scale fading. In general, we try to approximate the amplitude/power of a received signal using a suitable distribution. Basically, Rayleigh distribution is sufficient to model amplitude in urban areas, Rician distribution suits better in sub-urban areas where LOS components exist, and Hoyt distribution models scintillation effects. As earlier mentioned, Nakagami-m distribution is a generalized case and includes the three distributions as special cases. Means if we are done with the analysis for Nakagami-m fading, it is equally applicable in any of the above mentioned fading environments (m<1 for Hoyt, m=1 for Rayleigh, and m>1 for Rician).
    Moreover, approximation using Nakagami-m may not be optimum, specially at tail, and for those cases more generalized and accurate models (kappa-mu/eta-mu/etc.) need to be used.

  • Akpan Jimmy Essien added an answer in Speech Recognition:
    What are the benefits of syllable segmentation versus phonetic segmentation in automatic speech recognition?

    what would be the benefits to perform  a syllable segmentation in speech recognition compared to the phonetic segmentation or the opposite direction?

    Akpan Jimmy Essien · AJESSIEN RESEARCH

    If you do not have a syllabic segmentation of your utterance you might find it difficult to specify the phonemic components in the phonetic representation due to articulatory compensations and the resultant  mutual overlapping. In fast speech, you could find yourself with a lump of continuous voicing with very little demarcation points (if any). A choice of speech samples with voiceless consonants to create some syllable markers would be of help.

  • Verena Hoelzer asked a question in Mangroves:
    N which extend can the Shannon-Wiener index be used among different habitats?

    For my study I am comparing diversity of mangrove epibiont communities among estbalished, reforested and deforested mangrove sites. In which extend can I use the comparison of Shannon-Indeces in-between sites ? How important is the environmental setting and similarity of habitats to apply the Index calculations ?

  • David L Morgan added an answer in Participatory Design:
    What is the best way for validating an exploratory, participatory qualitative research ?

    The methodology is an exploratory, qualitative participatory design methodology. Data were collected using co-design and co-creation workshops that included arts-based activities and semi-structured recorded interviews.

    David L Morgan · Portland State University

    The steps you describe are all good contributions to the trustworthiness of your conclusions, and they would be as much as (or more than) I would expect for a thesis or journal article.

    One other concept from Lincoln and Guba that you might consider is "transferability," which is their alternative to generalizability. The key question there is the range of other settings where you results might apply. In other words, who else might benefit from thinking about the things you have learned.

  • Hein Van Gils added an answer in Hybrid:
    Are there any works about horse mackerel (Trachurus trachurus) and cunene horse mackerel (Trachurus trecae) hybridisation in waters of West Africa?

    http://www.fishbase.org/summary/371 (Trachurus trecae)

    Hein Van Gils · Min of Environment & Tourism, Namibia

    Both mackerel species occur off the Namibian coast, but hybrids have not been reported to the best of my knowledge.

  • Regina Wikinski added an answer in Medicine:
    What makes it difficult for guidelines to be followed?

    Benefits of restricted transfusion vs. liberal in certain patient groups; No role of renal dose dopamine; No role of FFP to increase serum albumin levels; Voluven (starch) predisposes to increased bleeding post-cardiac surgery, etc.  Such and many others.  Inspite of adequate proof, what are the factors that you think or may have encountered which make non-compliance/hesitance/reluctance with the published studies?

    Regina Wikinski · University of Buenos Aires

    Guidelines depends on experts consensus. Such consensus must be very clear and  show synthetic writing. I agree withTausit's reference to different egos intervention.

  • Nizar Matar added an answer in National Identity:
    Will a multicultural policy succeed in a state built on national identity and on the ideology of one language, one state, one nation?

    The contemporary European model of nation-state is based on the ideology of one state, one nation and one language, so we can follow many conflicts involving nationalism and multiculturalism. How can we overcome this contradiction and to ensure equal rights for all? After all, multicultural environments, today and in the past (before the European model of nation-state), are a reality.

    Nizar Matar · An-Najah National University

    My answer may seem to be unusual since I'll approach the subject from a chemist's bird's eyes. In chemistry, we used to classify catalysts into (2) types: (i) Homogeneous (which means that the catalyst exists in the same phase as reactants). (ii) Heterogeneous (which indicates that the catalyst exists in a phase different from the phases of the reactants). This classification went on for years & is still adopted in general introductory courses.

    Recently, progress in the field of catalysis increased the types to (4). The two additional types are: (iii) Homogeneously hetrogenized catalysts. (iv) Heterogeneously homogenized catalysts.

    Now, apply types (iii & iv) to answer the question about co-existence between nationalism and multiculturalism within a national state setting and there ought to be a way out from what appears to be a paradox. Human intelligence can work out a satisfactory resolution which is good for all provided that earnest intentions prevail.  

  • Mariam Ahmad added an answer in Patient Rights:
    Is nipple pinching the gold standard to arouse "LOC" patients?

    I have noticed nipple pinching being conducted on women "LOC" patients in my local hospital for no apparent reason after giving tramadol and metroclopramide.

    1) It is not done by the locals but (without prejudice) Indian national Staff Nurse. In fact, she teaches the other two China national and Pinoy nurses the "gold standard" way to arouse such patients.

    2) The "standards" were mere teaching sessions because she has no known agenda to actually arouse the "LOC" patients.

    3) I questioned her action, whether

    a) was it ethical to do so considering both drugs have just been administered?

    b) what happen if her nails are infected as she did not used gloves during the pinching?

    c) what if the patients are lactating, considering, the nurse did not check the patients background?

    d) worst still, what if the patients have unknown cancer?

    e) also, the nipples come out and beyond fixing as the patients are older and gravely fragile and ill patients?

    f) alas, the motive of using such primitive and barbaric "gold standards" never existed, as confirmed - it was just a night duty "killing the boredom of seeing too many sick patients sleeping so soundly" because they have to work late at night.

    I am now trying to check with the local relevant authority for the need to adopt such "gold standard" even to a real LOC patients

    - Can anyone in any country advise if this "gold standard" is normal in your own country?

    - I am trying to enumerate and record such pathetic accident at ED and ward level for research purposes.

    - Thank you - Mariam

    Mariam Ahmad · SIM University

    Thanks all,

    I do agree Nader, those world experts in "LOC", kindly assist to tell us the best way to arise such patients especially at ED, telemetry, Hi-D, ICU and ward staffs level.

    We totally need help to weed off unethical actions adopted by "modern" people who adopt primitive and sometimes barbaric way just to confirm if the "LOC" patients  truly acquire organic illness resusc first and inorganic thereafter.

    Aren't we all professionals after all? Let the discussions "roll on".

    1) What is ethical?

    2) What is barbaric or primitive? Nipple, ear, thigh pinching? Ammonia, acetone usage?

    3) Charlotte recommendations are valid but are they used in "your" country(ies)?

    I am trying to compile the research for best and worst "LOC" practices per country basis, if possible.

    Thank you - Mariam

  • Thomas Ye added an answer in Algae:
    How can I remove extracellular algae from hydra so I can get purified culture of the endosymbiotic algae inside?

    I am trying to isolate endosymbiotic algae from green hydra and culture them. Literatures in the past that claims to succeed in doing so cannot ruling out possibility of being contaminated.

    Some basic routine is to wash the hydra and centrifuge it, however, there could still be algae attached to the sticky basal.

    Would it be a good idea to chop the basal off and rinse the left part? Any techniques I can kill algae outside while not harming endosymbiotic ones?


    Thomas Ye · Rice University

    Hi all,

    Thanks for your answers.  For Antoine, I am trying to separate contaminated algae from target algae. The problem is both share similar appearance and are hard to tell from.

    For Oded, I read some papers using homogenizer and centrifuge, it's easy to wash off host tissue, but still hard to get rid of the contaminated algae. What if you have other algae in your culture? Do you try to pick them out later?


  • Subrahmanya Kumar N. added an answer in Exchange Rates:
    To study the relationship between stock market and exchange rate, how can we use data of exchange rate for the European Countries?

    I am studying the relationship between stock market and exchange rate in European and Asian countries since 1995. But many European countries opted for Euro in 1999. So the Exchange rate becomes static for 15 European countries after 1999. If I study after 1999 than the exchange rate is common for all European countries.

    Subrahmanya Kumar N. · Srinivas Group of Colleges

    You will have to divide your study into two time periods 1995 to 1999 prior to the usage of Euro and 1999 and afterwards after the acceptance Euro in order to get a clear relationship between exchange rate and stock market. There is no choice but to use the exchange rates of all European currencies prior to the introduction of Euro and Euro at the later dates. Similarly the changes in exchange rate should be adjusted at the time of introduction of Euro to take into account the fluctuations in exchange rate due to the introduction/acceptance of new currency.

  • Saeid Abolfazli added an answer in Wireless Communications:
    What will be the next technology that can be seen in wireless communication field?

    By the upcoming technolog,i mean the next advancement that you see in the field of communication. 

    Saeid Abolfazli · University of Malaya

    Thanks Simon for referral. Please find below papers too. 



    Good luck and enjoy reading

    Saeid Abolfazli

  • Artur Burzynski added an answer in DNA-Protein Interactions:
    How to find out DNA binding amino acid sequence in a protein for DNA-protein interaction?

    By sequence analysis how to bind out DNA binding sequences (aa). Any tools available Please let me known?

  • James Kelly added an answer in 19th Century Medical History:
    Does anyone know articles or studies concerning visual representations of tuberculosis patients in the 19th century?

    I am interested in the visual representation and iconography of tuberculosis and male tuberculosis patients, specially concerning art and male artists. Any suggestion?

    James Kelly · Brighton and Sussex University Hospitals NHS Trust

    ICONCLASS is a good resource. It's a subject specific international classification system for iconographic research and the documentation of images.

  • Regina Wikinski added an answer in Adipocytes:
    Does enhancing cell membrane permeability increase free fatty acid in blood?

    If the membrane permeability of adipocyte increases via some physiological events like ROS generation etc. will that result into more free fatty acid liberation in blood stream? Please give reference.

    Regina Wikinski · University of Buenos Aires

    FFA from adipose tissue increase in blood when  low insulin sensitivity of Intracellular  Adipose Tissue Hormone   induce adipocyte Tri Acyl glycerides lipolysis. 

  • Jim F Malone added an answer in Radioactivity:
    Is it dangerous for the staff, inpatients or outpatients at a hospital to care for radioactively contaminated patients or to be near them?

    researcher who has experience in radiation 

    Jim F Malone · Trinity College Dublin

    As others have said above, every day in hospitals many patients are injected with significant amounts of 99m-Tc for nuclear medicine scans.  There is a vast experience in how to deal with this.  Generally the problems with 99m-Tc are relatively easy to manage as it is a short lived radionuclide (6 hour half-life) that only emits gamma radiation.  This means that the dose from accidental injestion through contiamiation are relatively low.

    On the other hand nuclides that emit beta or alpha particles give very large doses if injested as all their energy is absorbed in the tisues.  This is the case with 131-I, which has significant beta and gamma emissions, and is also used medically.  Sometimes very large activities (several GBq) are used for thyroid cancer treatments in patients.   In these cases patient emissions of gamma radiation can give significant radiation doses to people in their immediate environment.  In addition their living space can be contaminated by body fluids like sweat, saliva, urine and faeces.  Special measures are necessary to control this.  In many countries the patient is isolated for a few days and is released from hospital after their retained radioactivity drops below a formally set threshold.  The threshold varies somewhat from country to country with Germany being very demanding and the US being laisez faire.  The IAEA published a Safety Report, which goves a good account of how to manage the situations in which individuals have been given these large activities, and of practice in different countries. See: 

    Release of Patients from hospital following radionuclide therapy. IAEA Safety Report Series No. 63 2009

    This can be downloaded from: