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  • Sandra Leaton Gray asked a question in Biometrics:
    Is anyone else working on the use of biometrics in schools?

    I've developed a research strand on this in the past and I am now revisiting it with Prof Andy Phippen from Plymouth, and we are keen to know if anyone else is developing new research in this area as well. We are mainly interested in attitudes and behaviours towards biometrics amongst pupils, teachers, parents and governors. We are also interested in the technical side, for example system failure. 

  • Nebo Chidiebere added an answer in Participatory Research:
    Do participants read instructions?

    Can anyone recommend any papers that test how many participants in research studies actually read the instructions correctly and follow them?

    Nebo Chidiebere

    i support your view George. most researcher are in a rush to complete questions and at the end many look at the instructions, only to find out they followed the wrong path


  • Sergei A. Markov added an answer in Algae:
    how to remove algal biofilm in a tubular photobioreactor?
    Algal biofilm formation effect the light transmission in a PBR and decrease productivity .
    Sergei A. Markov

    You can use compressed air and some kind of cleaning soft sponge.  Air will push sponge through tubes and clean their walls from algae. You can later use magnets for cleaning fish tanks to remove any remaining algae.

  • Debra Sharon Ferdinand added an answer in E-Learning:
    Whats is your opinion regarding the future of e-Learning?

    I am interested to do a prospective analysis about the e-Learning

    Debra Sharon Ferdinand

    I think it would be upgraded to u-learning with the growth in mobile devices and faculty and students would have to quickly adapt their teaching and learning to accommodate these mobile devices in writing more concise content while students would need to be adept and reading and analysing this content (if need be do further reading for clarification) as part of their learning process.

    Best regards,


  • Kazi Aminul Islam asked a question in Neural Networks:
    NARX neural network on EEG signal?

    Can anybody help me how to use NARX neural network on EEG signal? After training I want to use additional Input to predict part of the signal.

  • Seda Tht added an answer in Triacetin:
    Convert to Units in Lipolytic activity assay?

    I have assayed the lipolytic activity of lactic acid bacteria isolated from olives by spectrophotometric method. I used lipase from porcine (Sigma) to generate a standard curve.  I tested bacteria but I can't convert the results from microgram to Units.

    The lipase box says following:

    Lipase from porcine pancreas
    Type II, 100-500 units/mg protein (using olive oil (30 min incubation)), 30-90 units/mg protein (using triacetin)

    So, 1 microgram/miligram = How many Units? I couldn't calculate this. Please help.

    Seda Tht

    Unit Definition
    One unit will hydrolyze 1.0 microequivalent of fatty acid from triacetin in 1 hr at pH 7.4 at 37°C. (pH 7.7 is used with olive oil as substrate)

  • Nebo Chidiebere added an answer in Public Administration:
    What can the nature of values in the public administration be?

    Do You agree with Ch. Hood's division of the values nature in public administration as hierarchical, egalitarian, fatalistic and individualistic?

    Nebo Chidiebere

    i feel that the value system in public administration can also be affected by the environment and culture of the people. there is need for transparency in value system of any civil service to allow for participation and accountability of government at all levels 

  • Ruth Nebel added an answer in Movement Analysis:
    How can I make an interdisciplinary theme understood?

    I am working on an important theme that has aspects of dentistry, neurology and movement analysis. The dentists do not read the neurological and movement aspects and the neurologists do not read the dentistry part –so since years, nobody gets the important point and it is not possible to make a study. My theme is that spatial orientation is subordinate to spatial synchronization – the synchronization, however, determines body posture, movement and may be responsible for severe pain. Synchronization is determined by the position of maxilla and its teeth. It is necessary to get all of the aspects to understand the connection. Benefit: to be able to cure therapy-resistant back pain in craniomandibular patients. What can I do to make the aspects understandable for the involved disciplines?

    + 1 more attachment

    Ruth Nebel

    Dear Lydia,

    oh I am sorry, I think have not expressed myself well: I thought to meet you with your patients for a day and show some effects in teeth alive. We could take a video of their movements  to have another closer look at it afterwards. Your idea is good as well: I have just looked for a video, but I did not find some which shows the movements in a good comparison and that I am allowed to send. So I begin attaching some series of movements that are arranged in two rows for comparison: the row above shows movements with nearly normal length of upper teeth and the row below shows movements with reduced length in upper teeth right lateral and dorsal. Please write me if my explanations of the figures are not understandable.

    Best wishes,


  • Baig Abdullah Al Muhit added an answer in Bessel Function:
    Can anyone suggest books on the fundamental understanding of bessel functions with worked examples?

    can anyone suggest books on the fundamental understanding of bessel functions with worked examples?

    Baig Abdullah Al Muhit

    Thank you everyone for your valuable time and reply. All the information helped me enormously.

  • Debra Sharon Ferdinand added an answer in M-Learning:
    How to combine m-learning and e-learning?

    Videos and images are common used in e-learning and many platform can support them. Contents for m-learning must be designed in order to fulfill QoS itself (speed, process, size, etc). Any suggest or experience about combining contents for e-learning and m-learning?

    Debra Sharon Ferdinand

    You may also look at this study that combines m-learning and u-learning in social media:


    Best regards,


  • Mewael Giday Sertsu added an answer in Thin Films:
    Is it feasible to make thin films of CeO2 in E-beam facility?
    Does anyone have experience in making films of this material?
    Mewael Giday Sertsu

    Hi Kai

     Well we tried. We used both E-beam and DC-magnetron sputtering. I agree with you for Ce deposition the E-beam could be better but for CeO2 deposition Sputtering also performs well.   Our aim was to check reflectivity performance of B4C/CeO2 ML on Si substrate at 6.x nm wavelength ( since theoretical simulations show good optical contrasts at those wavelength) and found out that measured R was 4 times less than the theory. The severe problem was the interface diffusion at the interfaces that made the reflection very low.  However, as a first time deposition of this kind of MLs the results are not so bad and could be improved by choosing well controlled deposition processes and introducing capping structures. 

  • Jaafar El-Murad added an answer in Strategy:
    any one working on Non Market strategy
    Integration on market and non market strategy
    Jaafar El-Murad

    You mean things like ethics, green issues and so on?

  • Viktor Dmitriyev added an answer in Search Engines:
    Which one do you think is better in indexing and searching large PDF and OCRed documents? ElasticSearch, Solr or simple Lucene?

    A number of open source solutions are available that can be used in indexing and searching documents. However, I want to index and search large PDF documents. Which one should I use, ElasticSearch, Solr or simple Lucene? And why? Does any body know any open-source solution or project that has used any of these or others for the said purpose?

    Viktor Dmitriyev

    The very first problem (as it was already mentioned above) is to convert pdf-s to a pure text files. For instance, I used simple, but yet very powerful utility called "pdftotext"(https://en.wikipedia.org/wiki/Pdftotext). The pdftotext utility usually comes with LaTeX packages. One problem is that filtering of unnecessary symbols generated during conversions is required afterwards. Other problem is that conversion process is not fast, but it can be easily palatalized in case you have multiple machines. And as long as you will have text from pdfs, you can use any full text research engines available.

  • István Lénárt added an answer in Number Theory:
    Would it be useful to have a representation of finite affine planes showing their polynomial forms and dihedral actions on those representations?

    I have discovered elementary connections between number theory and affine planes. I recently posted some of my notes, calling the paper "A Representation of Finite Groups and Their Dihedral Transformations". Shortly after posting the paper I discovered the axioms for an affine plane which lead me to realize that I was rediscovering Marshall Hall's results published in 1953 showing the connections between affine planes and ternary rings. Now I am studying Hecke algebra and Frobenius Reciprocity and seeing connections to some of my other observations.

    I am hopeful that someone will point me to wherever the results in my notes are, or confirm that they are unique. If so then I will continue studying Frobenius inversion and work on demonstrating it in the language I have been developing, otherwise I would like to know what has been done so I don't spend too much time re-discovering the wheel.

    Thank you for any comments.

    István Lénárt

    Dear Friends, most of the information in David's posts are relevant and extremely valuable from my selfish 'spherical' perspective as well. (A title from the huge literature from which a tiny little fraction is known for me: Ueberberg, I.: Foundations of incidence geometry. Springer, 2011.) My proposal is to offer a different option to the same set of geometric experience, without casting any doubt on the significance of the approach that prevails presently in this field. Leibniz wrote to Huygens in 1679: 'I am still not satisfied with algebra... I believe that in geometry we need another analysis which is directly geometric or linear and can express situation directly as algebra expresses magnitude directly.' This letter became widely known in the 19th century, in the period of great discoveries by Carnot, Staudt, Moebius and many others. I think that my proposal is a step forward, however small, in this same direction. Klein, Hilbert, Banach and others derived geometry from the theory of groups. Maybe the inverse route is also viable in several cases. An example: The theorem of Gleason about Fano planes being Desarguesian planes, can be formulated and proved for Fano spheres and Desarguesian spheres strictly on the basis of the above system of axioms. If this is true, then the lemmas from group theory that are necessary to complete the original proof may be interpreted as consequences of the proof in the axiomatic system of projective spheres.

  • Daniel Rivas added an answer in Cognitive Science:
    Can a Biosemi EEG setup be fully run on a single computer?

    I have only ever seen it run on two, and Actiview uses USB ports as trigger inputs. Our lab would benefit, however, from using one computer to both run our experiment and obtain trigger-marked eeg data so that the extra computer is free to perform data analysis simultaneously. 

    Any help would be greatly appreciated.

    Daniel Rivas


    Our lab just finished migrating to new, powerful computers that do not possess parallel ports. I have finally found a way to run our experiment and send triggers on a single computer. The method takes advantage of the fact that the actiview software can respond to keypresses, specifically the functions keys F1 to F9 inclusively. I use PsychoPy, and hence, python. Using the pywin32 library to make system calls, you can send keypress events to the actiview window and thus simulate someone actually pressing the function keys. Note that this will not work if your design needs more than 8 different types of triggers. Feel free to email me for more details on my implementation.

    Hope this helps!

  • Mohammad T. Raad added an answer in Tungsten:
    How do I calculate the coating density for ASTM G65 test ?

    I have substrate of law carbon steel (AISI 1018 ) with thickness of 10 mm, only one face of the substrate is coated by HVOF method (high velocity Oxy fuel), the coating type is Tungsten Carbide Nickel chromium (WC-Ni-Cr) , the coating thickness is about 250 -300 micrometer.
    Is there any easy way to calculate or to measure the density of such this coating, because I am doing ASTM G65 test ( Dry wheel test)?.and the required density in the G65 standard formal it should be the coated density NOT as the powder density.

    I tried different ways , but in each time I got different result, also I tried ASTM B 311-13 test.

    Thank you 

    Mohammad T. Raad

    We measure the weight of the steel plate before coating, then to accurately weigh it again after coating, using the area coated and the average thickness you can calculate the density of the coating.

  • Yue Li added an answer in Homologous Recombination:
    How do I enhance the efficiency of homologous recombination?

    Hi dear biology fellows. I'm pretty new to genome editing..

    We are considering the possibility of using CRISPR/Cas9 to do knockins.

    Any ideas on how to enhance the efficiency of homologous recombination??


    Yue Li

     any ideas how would i apply that principle in zebrafish..?

  • Jaafar El-Murad added an answer in Analysis & Interpretation:
    How the creativity as a topic can be under analysis to be interpreted along the design process in architecture?

    ¿whats mental's tools can improve our creativity in de desing process in architecture.?

    ¿how the creativity work in architecture?

    ¿Are There specific studies on creativity in architecture?

    Jaafar El-Murad

    This is a rather broad set of questions Josua. It's probably easier to start with the last (Q4) - "Are there specific studies on creativity in architecture?" The short answer is "yes, there are". A quick Google search will reveal several. If you search a specialised database such as at your university you will find more. Some of these will include something on how creativity works in architecture (Q3), and how to improve your creativity (Q2). The answer to Q2 will include things like being prepared to take creative risks, because of the strong relationship between risk and creativity. Your headline question (Q1) suggests that you are thinking of embarking on a study about creativity in architecture. That could be very interesting - good luck!

  • Rinaldo Nicoli Aldini added an answer in Instinct:
    Why do we fear Death ?

    Our rational intellectual side tells us to accept what we cannot change...

    Even as we may consider our Human species as the only rational species, our instictive animal side moves us to fear our own death, more than any other danger...

    What moves our survival instinct to prevail among any other human more rational capacity?

    "Why do we fear something about which we don't know anything?"" (((Roland Moraru))

    Rinaldo Nicoli Aldini

    An opinion of a Genius of the Renaissance, Leonardo da Vinci: "Sì come una giornata bene spesa dà lieto dormire, così una vita bene usata dà lieto morire" (As a well-spent day brings happy sleep, so life well used brings happy death).

    But, how many of us can really spend well their own life, can feel to have fulfilled at all their potential for the common good? How many of us approach the finish line with the feeling of having done all the positive things they wanted, of having no more plans for the future? The fear of death in humans, in my humble opinion, is also (but not only) linked to this: to fear (rightly) the 'too early'. It is linked also to the idea of the end of our individuality, of our being, it is a necessary consequence of biological 'survival instinct' in a rational but also emotional being. The fear of our death (as well as of death of the loved ones) shows that human life is an immense gift, which we fear to lose. Faith and hope for a transformed, future life, according to religious belief, help us to overcome this fear.

    Rinaldo Nicoli

  • Ahmed Halfadji added an answer in Hexanes:
    Which is best clean up procedure for PCBs and other organochlorine compounds from sediments?

    I am extracting PAH, PCBs and other organochlorine compounds using 100%DCM. Then added 100% Hexane in it and concentrated to 1 ml. Then separated the extract in to two for both PAH and organochlorine compounds.

    I want to know is the cleaning procedure for organochlorine compounds including PCBs can be done by  96% sulfuric acid or dichromate??

    Is there any column chromatography step needed for PCBs and organochlorine compounds from the above procedure?



    Ahmed Halfadji

    Dear Michael Peach,

    thanks for your good question;
    we can use an internal standard, added it in sample in the extraction step before clean up step for control and estimate to calculate the recovery , and also other internal standard after clean up for quantificative analysis of analyst in GC system or LC system.

  • Mari Galiher asked a question in Self Disclosure:
    How have you seen individuals self-disclose on Facebook, Twitter, or YouTube?

    I'm interested in research on: individuals with mental illness, self-disclosure, social media networks.  

  • Qamar Farooq added an answer in Physical Chemistry:
    Anyone knows where can I find a free pdf format of the book: "Quantum chemistry" (MCQuarrie)?
    I need 1 book: "Quantum chemistry" - MCQuarrie and solutions problems of this book. Please help me to find free pdf format of this book.
    Qamar Farooq

    Can anybody send me the solution manual of Physical chemistry by D.A.McQarrie to me. My Email is 17100261@lums.edu.pk

    P.S If it do not works, other one is mohd.qamarfarooq@gmail.com.

    Thanks in Advance

  • Espen A. Sjoberg added an answer in Behavior Analysis:
    How does cognitive psychologists view behavior analysis?

    I am currently researching within a field called behavior analysis, which is essentially modern behaviorism. Researchers in this field tend to emphasize different methodologies, such as single-case designs, and often avoid statistical methods.

    In terms of psychology, behavior analysts are not interested in cognitive phenomena. This is not because they reject the existence of private events, but because they argue that cognitive events cannot be observed; only its behavioral outcomes.

    There are several papers that address how behavior analysis sees cognitive psychology. They often refer to the misuse of hypothetical constructs and unnecessary group designs. However, I was wondering if there are papers discussing behavioral analysis from the cognitive psychologists point of view?

    Most psychology textbooks will refer to behaviorism as dead, often with reference to Chomsky's critique of Skinner. According to behavior analysts, Chomsky's critique is flawed, but in mainstream psychology, behavior analysis remain a minority subdiscipline.

    So, I was wondering if there are any good articles discussing cognitive/internal/private events, and behavior analysis/behaviorism, that are written from a cognitive psychologist point of view? There are plenty such articles in behavior analysis journals, but I am wondering if the issue of cognition vs. externally observed behavior have been discussed elsewhere, from a cognitive viewpoint?

    I guess what I am asking is, what papers from cognitive psychology exist that address why behavior analysis is obsolete, and internal, private events are perfectly acceptable to investigate?

    Espen A. Sjoberg

    Nicholas, I have to (mostly) agree with you regarding your point on evolution. Indeed, some behaviourists seem to think that learned behaviour can evolve from one generation to the next. This is certainly true if we are talking about cultural transmission, but not necessarily so if we are talking genetically. If an organism acquires an advantageous behavioural trait via learning in their lifetime, then there is no guarantee that the offspring also will have this trait. It can only acquire it by learning through the parent, or by some random chance mutation.

    It is equivalent to shaving one's head every day and expect the child to be born bald. It is, essentially, a version of Lemarckian evolution.

    Nevertheless, in my experience, most behaviourists are fully aware of the effect of evolution and genetic predispositions, especially recently. They tend to focus on learned, reinforced behaviour and cultural transmission, where I certainly think behaviourist principles are important.

  • Linda Fuller added an answer in Educational Policy:
    What changes in education policy related to technology do you think are necessary to fully embrace its potential for learning?

    In the US at least - we are somewhat hampered by policy related mandates on what should be taught and how it should be taught and assessed. This inhibits the integration of technology for many of the high impact practices that theory would lead us to believe will make a large difference in student learning. What changes do you think need to be put in place to change the current architecture in such a way to afford better technology-mediated/integrated learning? I would love to hear not just about changes to US policy - but also policies that other countries have put in place that are making a difference with respect to the use of technology in the classroom.

    Linda Fuller

    I've heard that sense of scrambling yet always being "behind" in the states as well, Guenter. I wonder whether we are "tackling" the changes technology brings both effectively and realistically? Is it most important for us to incorporate tech the way the business world might? We hear that top digital gurus still send their primary age children to very low tech schools - perhaps most of this thread refers to post-secondary institutions - or at least high schools. I like the idea of always asking how will this change improve/enrich our lives (not in the future, but in the present) and how will it help us to build on our current capacity to be the best we can be at a very human level?

  • Kenji Katsuragi added an answer in NGOs:
    Any opinions on Sector Neutrality of Accounting Standards for NGOs and the Public Sector ?

    Do u think that the NGOs and the Public Sector using the accounting standards which are sector neutral.

    Kenji Katsuragi

    In Japan we have next  accounting format  for MPO/NGO.


  • C. Allen added an answer in Geophysics:
    What is the cause of this warming?

    In Sept. 2015, Ukrainian Central Geophysical Observatory  fixed just three temperature records in Kyiv.

    1)            Maximum temperature+35,7°C  was in Sept. 2.  This day was the warmest September since 1881.

    2)            Also on this day on 6,5°C was exceeded and pre-historical significance of the average daily temperature, which was fixed in 1938. The average temperature reached +29.1°C.

    3)            In addition, 3 September in Kiev was fixed very warm night of 1881 to that date. Night temperature is not dropped below + 20,6 ° C and thus on exceeding 3,1°C prior to the historical significance of this day in 1899.

    P.S. Most water wells disappeared. This has not been a long time !!!

    C. Allen

    Dear Kenneth & Yuri,

    One thing to consider is that CA has one of (if not the) most depleted catchment basins in the world so that evaporation via transpiration has virtually ceased. This has significant effects on evaporative cooling and thermal inertia so this could explain recent heating there. I do not know whether the same may be true elsewhere. As a side issue, this appreciable loss of water mass will cause localised isostatic rising that will reduce friction between the tectonic plates and some faults so permitting then to release energy sooner or in different locations.

    As regards my reasons for remaining quiet on the “Earth-change” paper: initially (for 6 years) the study was endorsed by my work and had their name and email as a contact on it along with all full names of those in the acknowledgements plus myself. Just as it was going to publication things changed (mostly politically, but also as an organization under an efficiency review). The institution had written a press release but withdrew it immediately before its release. I was permitted to use it for myself, but it made no sense outside the context of work. I offered to remove all references to my workplace so as to avoid targeting my section, including removing full names and easily searched names and this was accepted by upper management. Immediately after this my immediate supervisor demanded that I "could not advertise it in any form, even as a private citizen". So the paper was actively gagged and as such I lost all avenues of international or even national dissemination. Despite this the paper had over 57,000 downloads on ResearchGate prior to ResearchGate switching to reads. I couldn't reveal my name, institution or anything that might lead to identifying my workplace (i.e. not even my country), nor can I have a press release any more. That is why I used a ResearchGate account as a contact on the paper since it shows I'm from an internationally recognized research institution (you can't get an account with them without it). I stripped out the institution details and asked ResearchGate for permission for an initial only for my name (that was new to them). I also signed a statutory declaration with the publisher to permit removal of an institutional contact from the paper. The advertising of this threatens my livelihood so I can't reveal my identity in any form in case it leads to my institution. I thus have lost all local and international contacts to get it disseminated. I no longer can present it to conferences for the same reason (although it was presented at 2 conferences prior to the gagging). I can't afford to be seen to be advertising it so if it is “discovered” by the media or the likes of the IPCC then this must come from sources other than me. I was hoping to have the contents of this paper presented at the Paris meeting in November, but I do not have the means. I think the gagging was because it would “raise our profile as an organisation interested in extending the concept of Climate-Change” at a time of fiscal constraints and redundancies. I have just been made redundant, but I am applying for positions within the same organisation so can’t afford to reveal who I am just now. I don't want the notoriety (despite the effort in producing it), that is why I produced it as a peer-review review paper rather than as a book from which I could get notoriety and income. I believe the world and especially the poor of the Pacific Rim need to have it addressed. Kind regards. C Allen

  • Matthew G Keffalas added an answer in Process Optimization:
    Can we use Support Vector machine in optimization problem?

    Support Vector Machines are generally used for classification problems. They have been proved to be better classifiers than ANNs. However, i am not able to find any application of SVMs in process optimization.

    Matthew G Keffalas

    I just want to nitpick at one thing you said.  It has never been proved that SVMs are better classifiers than ANN, neither mathematically or experimentally.  Generally, no classifier is ALWAYS better than any other classifier on ALL possible datasets.  It's true that SVMs can work better on some datasets and they may have some more attractive properties than ANNs, but saying that SVMs are always better is misleading.

  • Mari Galiher added an answer in Journalism:
    How can location be used to tailor news to individual consumers in a way that goes beyond such "lackluster" units of relevance as zip code?

    Automated journalism is the process by which computers select the stories consumers see, and the order in which they see them.  Nearby location can make news stories seem more relevant to consumers (following Galtung and Ruge, 1965), but a more nuanced view of locational relevance than just a street address or zip code is required to drive the most compelling stories to consumers (such basic location information is deemed "lackluster" by Weiss (2014, p. 4)).  What factors could be used to enrich a computer's definition of a consumer's location to deliver the most interesting stories him or her?

    Mari Galiher

    Consumers could have stories catered to their interests and subjects that they enjoy reading. I would love to have stories that relate to my research interest in mental illnesses, social media networks, dogs, and so on. I've noticed that Facebook does feature stories related to my interests, but would appreciate if other platforms could do similar functions as well.

  • Gowri Sivaramakrishnan added an answer in Fixed Prosthodontics:
    Open tray or closed tray technique for implant impression!.. Which one do you prefer in your private dental clinic and why?

    Some clinicians prefer closed tray over the open tray but some discrepancies can appear in this technique. On the other hand the open tray technique is somewhat difficult and time consuming.

    Gowri Sivaramakrishnan

    I feel open tray technique is better. Reorienting the transfer copings onto the impression is difficult and may not be precise. Especially for multiple implants with different angulation. 

  • Matthew G Keffalas added an answer in Classification:
    Is the classification below supervised or semi-supervised?

    I have a set of data to be classified and out of this I take 10% for training.While for testing I am using 100% of the data that has to be classified.

    I'm in doubt,whether the classification is supervised or semi-supervised??.

    Thank you in advance. :D

    Matthew G Keffalas

    I think everybody else has already hit upon everything but I'll just repeat:

    1. Training and test data should be completely separate.  In your example, the 10% of data used for training is also used for testing (since you use 100% of data for testing).  This is a bad procedure.
    2. You haven't given enough information for us to determine if your problem is supervised or semi-supervised.  The level of supervision is determined by the labels available for the training data.  If all of the training data is fully labeled (i.e. you know the classification target for each training sample), then that is supervised learning.  If some of the training data is labeled and some is unlabeled, that is semi-supervised learning.