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  • Dejenie A. Lakew added an answer in Fluctuations:
    Could you please tell your point of view on the current situation worldwide ?

    Is it a stable or fluctuating and we are faced to the glabal danger

    Dejenie A. Lakew

    It is true that systems in nature loose energy and tend to be in lesser order in time by the principle of thermodynamics and the human society will not be different. We passed through such states of existence in a cyclical manner and returned to normalcy, the state of existence our collective well being demands.

    Therefore what keeps us together is our higher order consciousness and thinking capacity to override the natural tendency of entropy by creating new and stronger binding laws, orders  and controlling mechanisms not to loose cohesion, as we come to know cohesion is our strength to survive than going apart.

    Individuals and few groups of individuals tend to display impulsive behaviors of that are centered on individualistic and group satisfactions, which are devoid of thoughtfulness, knowledge of the past  and wisdom, to create chaos and orderlessness,  contrary to the collective desire and well being of society, which at the end society changes course to the better.

    After world wars I and II, time has elapsed with strong sense of communal purpose, order of stability and it seems the world is getting older and start to loose energy which leads to entropy once again. All human conflicts that were local and global, and which still are commonplace locally, scary mixed with human tragedies and tend to emerge to become global, are due to that virtue-less impulse of individual humans. Aside from what I put earlier as controlling mechanisms not to lose order, fear of the strength of the other is another mollifier that controls the temptation of being rouge.

  • Lai Nguyen Huy added an answer in Trucks:
    Does anyone has example of CO emission factor generated from natural gas-fueled bus or truck?

    Comparison of CO emission factors from natural gas-fuels bus/truck compared to other fuel such as (gasoline, diesel) of the same exhaust control technology.

    Lai Nguyen Huy

    Thank you so much for your responses

  • Abdalla M. A. Ahmed asked a question in Fiber:
    What is the difference between interfacial debonding strength and interfacial shear strength?

    Am I true?

    Interfacial debonding between fiber and matrix?

    Interfacial shear means fiber pull-out?

  • Mohsan Saeed added an answer in PCR:
    Cryptosporidium DNA works first time after extraction but did not work for next time?

    Has anyone know why after extracting Cryptosporidium DNA from feacal samples, the first PCR works well but when I need to run another PCR from the same extracted DNA, it dose  not work on gel picture although the positive control was working. I am using bioline kit but this issue happen many times for me. I hope to find help from you. 


    Mohsan Saeed

    Does Cryptosporidium DNA has introns? If so, check if your primers bind to the exon-exon junctions or to two different exons which are separated by introns. I am assuming here that you are using cDNA as a positive control.

  • Nawras H Mostafa added an answer in Silica:
    What are the issues regarding using coupling agent in fibre-reinforced composites?

    Hi everyone,

    I am looking for the disadvantages ( the mechanical ones) that related to use coupling agents in fibre-reinforced composites. As I found, there are two main problems arising from using such materials to enhance the bond strength between the matrix and the fillers (may be fibres). The first one is the degradation of bonding strength over time when the composites were exposed to wet environments. While the second one is that most coupling agents were used  for silica base filler materials, such as glass fibres, to activate the mechanism of coupling. Is that true? Any information will be highly appreciated.  Thank you     

    Nawras H Mostafa

    Dear Marcos and Marylinda,

    Thanks a lot for your help.  

  • Nawras H Mostafa added an answer in Fibre:
    How can I apply pretension in ANSYS for two glued parts?

    Hi there,

    I am facing a problem regarding the pretension loading. I need to apply axially uniform pretension load in the fibre prior matrix cure ( composite materials) and then releasing the pretension in the fibre after the matrix has been cured. I am trying the pretension section element but this method is correct if the two parts ( fibre and matrix) are not bonded to each other. I think pretension section is only work for bolted joints due to the non welded parts (non bonded) existence. If I apply the pretension section, the load will distributed non uniformly due to bonding between fibre and matrix after curing. The problem is very similar to prestressed concert simulation. 

    Thank you  

    Nawras H Mostafa

    Thank you Alaaeldin Elsisi for your help. I think you are right. Subsequently, do I need multi loading steps  to solve the problem as you suggested or only one step ?  and what about the prestress effects, do I need to activate it in the solution control ?

    Many thanks

  • Yabin Guo asked a question in RNA-Seq:
    Abundant sequences in RNA-seq?

    I found a lot of sequences such as:




    in some human cancer/normal tissue RNA-seq raw dataset.

    I can't find them by using blast. I wonder what they are. Are they from some spike in standard?



  • Tarron Khemraj added an answer in Political Development:
    How colonialism has effected institutional development and it's impacts on economic and political development?

    Any literature suggestions,,,Thanking in advance 

    Tarron Khemraj

    Hi Diana,

    This is an interesting question. In my view there are three schools of thought on this matter. I did a paper on this recently. My list of reference might be of help.

    Paper: "Colonial origins of Guyana's underdevelopment."

  • Apurva Ashok asked a question in Biotechnology Industry:
    How have biotechnology industries from 1970-2015 shaped and influenced technology in sci-fi films?

    There have been many studies about how sci-fi films make technology seem scary, which is why people don't trust science as much. Instead, I want to flip the question and see whether certain advancements in science correlate with science fiction film technologies, and whether the industry influences the films or the other way around? Any help is much appreciated!

  • Ümit Ergin Özen added an answer in Cyclic Voltammetry:
    How can I coat the working electrode sample on the Nickel substrate for taking electrochemical studies?

    How can I coat the working electrode sample on the nickel substrate for taking electrochemical studies?

    Ümit Ergin Özen

    Use a small brush for coating. And note that. your sythesised material+binder+active carbon+a solvent like alcohol or acetone.

  • Pengda Huang added an answer in Happiness:
    Any conclusion on judge whether a symmetric matrix with zero diagonal entries is positive definite or not?

    Say A=B*B^H (^H means conjugate transition)

    C=A - (diagonal of A). 

    So C is a symmetric matrix which diagonal entries are all 0. 

    I wondering whether there is any study on how to judge C is positive definite, or not


    Happy Thanksgiving!

    Pengda Huang

    Thank you, Prof. Morton E. O'Kelly.

    Eigenvalues can help me evaluate C. I am wonder whether there is a general criteria by which the C is positive definite or negative definite? or any on-going discussion on this? Thanks,



  • Simon Penny added an answer in Analogy:
    Is analogy the key to understand thinking?

    Hofstadter and Sander write in their book "Surfaces and Essences: Analogy as the Fuel and Fire of Thinking" that analogy is a key issue for cognition and perception. They put analogy into the center of all mental tools. I think analogy is a powerful tool but it is a tool beside others.

    Simon Penny

    > How exactly is the big bang contested?




    > Maybe it's not right, but we have no reason to doubt it for now.

    so its and educated guess ?

    > Since philosophical claims *always* begin with

    That is a fairly narrow definition of philosophy, imho.  I am as impatient with navel-gazing angels-on-the-head-of- a-pin kind o philosphy as you are, no doubt.

    > I am saying that when philosophy butts heads with science, science will win.

    And I, neither a philosopher nor a scientist, am saying its a false dichotomy.

  • M. M. G. T. De Silva added an answer in Water Cycle:
    Can you please suggest me about good software to model water cycle?

    It is good if the software is freely available and user friendly. It is OK evenn if it is an open source software

    M. M. G. T. De Silva


    Thank you very much for your suggestion. I'll look for Felow and will see whether it can be used for water cycle modeling.

  • Jerry Rhee added an answer in Scientific Method:
    Is the modern approach to cosmology fundamentally flawed?

    With the substantial amount of anomalies, paradoxes and unexplained phenomenon in mainstream cosmology, one must question whether the modern approach in this field is sufficient. In most fields of science, development proceeds according to the scientific method: A phenomenon is observed, a hypothesis is made, scientific test(s) are conducted and the simplest answer is sought after. However, this does not appear to be the path that modern cosmology is following (as demonstrated by the attached figure).

    Subjects such as naturalness and fine-tuning have been highly debated in the areas of quantum field theory and cosmology. The argument is that if a theory must be fine-tuned, then there should be an underlying physical reason for such values. However, the vast majority of fine-tuned theories lack explanation and only seem to exist for the purpose of reproducing reality in terms of ad-hoc mathematical formulations. Thus my question is really three parts.

    • Do you believe the modern approach to cosmology is fundamentally flawed?
    • Is a fine-tuned theory that is fundamentally wrong, but can still produce correct predictions useful?
    • Was Richard Feynman correct when he stated “Science is the belief in the ignorance of experts”?

    Examples in cosmology:

    • Redshift versus Luminosity Distance: Requires accelerated expansion via dark energy
    • The Faint Blue Galaxy Problem: Requires disappearing galaxies
    • Dark Matter Cusp Problem: Requires unnatural arrangements of dark matter in galaxies
    • Local Galaxy Counts: Requires a local "hole" that extends beyond 0.05z
    • Horizon Problem: Inflation theorized
    • Size of Distant Objects: Unexplained or significant evolution
    • Planck Sigma_8 Problem: Hypothetical sterile neutrinos proposed
    • Hemispherical Power Asymmetry: ?
    • Directional Dependence of Cosmological Constants: ?
    • The Dark Flow: Theorized interaction with another universe
    • CMB Cold Spots: Massive voids proposed
    Jerry Rhee

    Dear Ingo, I don't know what to say...


    Thank you!

    PS.  Thank you so much for your kind words.  It offers me much validation.  I am so honored!

  • Nirmal Aryal added an answer in Behavioural Economics:
    How do youths make their financial decisions?

    I want to carry on qualitative research methodology, what be the best method for exploration?

    Nirmal Aryal

    Thank you so much for suggestion for methodology. Can you pass research articles related to topic.

  • Ingo H. Leubner added an answer in P300:
    P300 based speller design - Is Row column information necessary ?

    Is it possible to classify the character without knowing the row-column information?

    p300 signal is generated when human are looking at flashing light. From the EEG signal correctly detection of p300 is important. After detection of p300 our job is to find what time this p300 signal generated and at that time instant which row or column flashed. From this row-column combination we can get the original character.

    Now if I don't have the row-column information. Is this possible to detect the character from EEG signal?  

    Ingo H. Leubner

    Sourav ,if  Row column information works, learn from it. However, you can also try ellipses, hyperbolas, and the form of the Spirals of the Milky Way. Since I am totally ignorant of your way, All I can and will do is to  encourage you to answer your question yourself and become in the process a successful Scientist! It worked for me and many others. Cheers, Ingo H. Leubner Dr. rer. nat. 

  • Rajshree B Jotania asked a question in Group Work:
    Is there any instrument to measure Magnetostriction curves of sintered ferrite samples?

    I am looking for Magnetostriction measurement of spinel and hexaferrite samples so any body suggest how to measure? which instrument can be use?. Our group is working on cobalt ferrite and strontium copper hexaferrites (M and Y type)

    R B Jotania 

  • Nirmal Aryal asked a question in Literacy:
    Can anybody help with research articles on Financial Literacy Youth (Age 14-16)?

    I am doing research on youth's financial literacy following mixed methodology. I am trying to identify the variables that define financial literacy in Nepalese context using focused group discussion and then conduct a survey to identify level of financial literacy among Youths.grounded theory methodology. I am looking for the research articles (empirical/qualitative).

    I would be grateful if anybody in this network sends me the works done in the field.

  • John Beiswenger added an answer in Autistic Disorder:
    Are you reasearching the causes for Autistic Savant abilities?

    I am interested in connecting with anyone who is researching the causes for the remarkable abilities of autistic savants.

    John Beiswenger

    Clodagh:  Thank you.  The solution to the autistic savant's amazing abilities will also be a solution to many other unsolved problems.  Let me know what you think of my research paper.  John     

  • Mark Azavedo added an answer in Questionnaire Design:
    How many questions is too many, in a questionnaire/ how long in time is too long to retain respondent interest?

    Ok, this question is asked over and over; and always comes back to the same, commonsensically, incorrect answer of "how long is a piece of string". I will be sitting attendees at a farmers' market down, as they leave, or we will be asking the questions, clip-board in hand. The environment is outdoors. I think, pretty obviously, if we say "this will only take an hour of your time", they'll walk away.

    It's obvious that the more questions I ask, the more respondent time I use, the more accurate will be the piece of research. However, there is the counter-point, in terms of respondent retention, that if their interest lapses, there may be no data at all, never mind data from considered responses. I, simply accept, that there's a trade-off.

    The question then becomes where, in reality, to action a judgement call. Specifically, how do researchers feel, given the circumstances I've mentioned, about 25 or 36 questions? I think 36 too many, but am inclined to think 25 OK. Any reading recommendations would be gratefully received, too.

    Mark Azavedo

    I should have added that I am adopting / adapting from literature review, in part wishing to see validity of US material in another country. The full question set implied by the particular piece of research I'm focused on, in my view, simply wouldn't be doable here in Thailand. In my view respondents will have long since run off, if a more modern Thai, or disengaged, whilst remaining and remaining polite, if more traditional. That means adaptation has had to contain elements, essentially, shortening, which I'd not envisaged, against many that I had. The latter were to do with other socio-cultural aspects in Thailand, for instance around cooking, but also around matters not singularly Thai, a reference to multiple nationalities present being a dynamic in itself.

  • Ivan Petković added an answer in Catheterization:
    Does your hospital use sterile or non sterile gloves for tunnelled CVC?

    I was just wondering if there is an increased rate for catheter related infection when using non sterile gloves at a tunnelled central venous catheter (Broviac, Hickman, Port a cath...). Interventions could be obtaining blood samples or changing the Infusion set.

    I worked at different hospitals and most of them don´t use sterile gloves anymore. Just disinfectant. And there haven´t been any infections related to that. I was used to it.
    Now on my new ward they use sterile gloves.

    Does anybody know if there is a study about it?
    I am working with pediatric oncological patients.

    What is your experience ?

    Ivan Petković

    In our institution, we use sterile gloves only when CVC is to be installed, after that all manipulation with CVC during  infusions or taking blood samples from CVC is done with non sterile gloves. However, we did not have any infectious complications so far. We work with adult hematooncological or solid oncological patients. CVC is installed only for continous chemotherapy regimens which lasts for several days. 

  • Paschalis Thomas Doulias added an answer in Griess Assay:
    How can I detect (NO3- ) and (NO2-) in micro molar concentration simultaneously ?

    Actually I want to detect Nitrite (NO2-) in presence of Nitrate (NO3-).

    I have already done Griess assay (which is not 100% reliable method) and tried fluorescence based assay using 2,3 diaminonapthalene. 

    Paschalis Thomas Doulias

    In biological systems  nitrogen oxide species exist predominately as nitrate (NO3) (uM range).   Nitrite exist is far less abundant followed by S-nitrosothiols in the pmole level. Reductive chemistries coupled to chemiluminescence detection allow for the detection of all these species. For your reference please read "Measurement of Plasma Nitrite by Chemiluminescence without Interference of S-, N-nitroso and Nitrated Species" Free Radical Biology and Medicine, 42: 1146-54.

  • Chen Yang added an answer in Trace Elements:
    Are there any books or articles about the basalt alteration in the ocean?

    I am willing to do some researches about the different kinds of alterations in the basalt in the ocean. And I want to know if there are some books or articles describing the changes of REE, isotope or major,trace elements during the alteration processes

    Chen Yang

     Thank you two for your answers that help me much. I am not familiar with this website so i did not reply until now.

  • Hamida Darwish added an answer in Thermal Degradation:
    Is there an equation to calculate thermal stress, vis a vis kerogen degradation?

    Pepper and Corvi (1995a) and Lewan (1985) mention thermal stress and its effect on kerogen degradation and the formation of petroleum.  Thermal stress involves time and temperature - is there an equation for thermal stress?

    Hamida Darwish

    Dear Nancy,

    Have a look this link will help you very much please.

  • Hugh Lachlan Kennedy added an answer in Waves:
    What is the transfer function used to find wave height (amplitude) from wave spectrum ?
    • How to find wave height from amplitude spectrum or from FFT Data.
    Hugh Lachlan Kennedy

    It also depends on how your spectrum is normalized. Does the FFT implementation use a factor of 1, 1/N or 1/sqrt(N)? I think MATLAB uses a factor of 1.

  • Marc Tessera 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.

    Marc Tessera


    I think you are confusing "objectivity" and "relevance".

    An approach may be "objective" but quite irrelevant.

    For instance, as already discussed with Joaquin, it is irrelevant to try to use an objective device (e.g., EEG or fMRI technique) to measure pain.

    The only relevant way to measure pain is by taking into account the subject's subjectivity through the self subject's report (e.g.,1-10 pain scale).

    "Psychophysic experiments or clinical trials are carefully designed.  If they are not then the reports will not be consistent and not representative of a group of people.  If not carefully designed, all kind of external influences will interfer with the results.  The more the choices will be constraint by the experimental procedure and the less room will be for feelings and imaginations if these are not supposed to interfere".  

    When you speak of "feelings and imaginations" in the text above I think you speak of feelings and imaginations of the investigators, thus of the subjectivity of the investigators.

    When I say that the relevant approach for measuring pain cannot be "objective" it is because it cannot be independent of the subjectivity of the subject who is in pain.

  • Octavio Francisco Torres Chazaro asked a question in End User:
    Are there other examples of End Users pulling the demand end as in the Intel case?

    Intel made famous the Pull-The-Demand form the user end, in order to avoid the Intel microporocessor to become a non-value , non-priced addition to a PC system.

    Are there any other documented case of this model of pushing the demand side? Can you cite any references?

    In particular I am looking at diverse ways to push the demand for hospital information technology and services from the patient side of the equation.

    Any ideas? Any review papers of advances on this topic?

  • Shabnam Yazdani Mehr asked a question in Adaptive Reuse:
    What types of problems are engaged in the adaptive reuse process?

    I am doing my research on adaptive reuse in architecture. I would like to know from an expert point of view, what are the problems in adaptive reuse that need more research? I thought about building typology, interior design and landscape in term of adaptive reuse. I also would like to know different ideas in this case. Thank you in advance for all your help.

  • Omprakash Kaiwartya added an answer in Postgraduate Studies:
    What is the simple and best simulator that can be used to simulate VANETS? Can NS2 alone can be used to simulate routing algorithms in VANET?

    Have to do the simulation for Collaborative learning Automata based routing for vehicular sensor networks as part of my post graduation project. Currently working with NS2? Is  adding IEEE 802.11p parameters in manet is sufficient to convert into VANET ? or we have to go for other simulators like MOBISIM,SUMO ?

    Omprakash Kaiwartya

    It depends on how much time you have for simulating your work for the academic project. Definitely it is not sufficient that you use NS2 only for simulating any VANETs protocols due to the the constraints of the simulator which was not developed for simulation of restricted mobility patterns.  Using SUMO and MOVE will be a good exercise but the thing is that it requires sufficient amount of time to learn the integration of these software with NS2. . 

    IEEE 802.11p with MANETs is sufficient for your master projects but not for publication in any reputed journals indexed in SCI. To simulate your Collaborative learning Automata based routing, firstly,  you must first concentrate on writing or updating routing agent  for incorporating your proposed technique during next-hop selection. Secondly, you should learn how to integrate your routing protocol in NS2 or how to update any existing protocol in NS2. According to my experience, Integration of new protocols is good as compared to updating of existing one. 

  • David Charles Wright-Carr added an answer in Neuroscience:
    What contemporary visual artists are applying principles from fields like neuroscience, neuroaesthetics, and visual perception?
    Scientific research has shed much light on how we see, and on how visual art resonates in our minds. I am interested in reading about contemporary visual artists who have applied this information in their creative processes.
    David Charles Wright-Carr

    Thanks, Louis. That's a great article, very much on topic. I'll put it in the growing bibliography for my students.