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  • Akilesh Ramasamy added an answer in NoSQL:
    What is the Best Database Structure for Big Data?

    I have a question about Selecting Type of Database for a system which may encounter to a BigData in future!
    Here is my questions:

    1.  Which one is better? SQL Databases Or NoSQL databases?
    2. If SQL is better! Does an infinite Table Structure (Relational Database) can make problems such Bad System resource usage? Or not? (in Other hand One table is better or Multiple (infinite) Table design?) for example, Consider facebook database for likes! is it better to we have a table for each post to store the likes of it! or It is better to we store all of the facebook likes into Only one table?


    Akilesh Ramasamy · Consultant Oral and Maxillofacial Surgeon

    Even though structured databases have become big enough and qualify as big data, true big data is mostly unstructured is the opinion of some of the Big Data Ninjas - meaning, if the data is structured, it not truly Big Data! (let's skip this aspect for the time being!)

    The question of SQL or NoSQL always comes up in this discussion and this is subjective to the kind of data that is being handled. The issue is if you have a constantly changing data and the database requires quick scalability, NoSQL is ideal.

    The big data is unstructured NoSQL, and the data warehouse queries this database and creates a structured data for storage in a static place. This serves as our point of analysis. The queries can be run as often as necessary.

    The data required for analysis can be stored in SQL. So NoSQL and SQL can and must be used in tandem for best benefits. NoSQL the benefit is quick scalability ... SQL is structured and standardized and can be scaled (may be not as fast as NoSQL but depends). So currently most industry experts prefer to work with both as the need requires.


    Dr. Akilesh. R


  • How soon can the demyelinating process start in mild traumatic brain injury?

    Traumatic brain injury, even in its mildest form, is known to result in degenerative processes including demyelination and dysmyelination of the axons over time. The shearing and tearing of the axons (primary injury) due to the acceleration and deceleration force of high velocity impact would also normally trigger off the secondary injury cascades. This includes the synaptic deregulation, cell death and axonal degeneration.  

    But how quickly does these processes start (especially the demyelination of the axons) in patients with mild TBI? I am of the opinion that it will take at least a few days or weeks before such degenerative process starts. What are your thoughts?

    Chandramouli Balasubramanian · National Health Service

    this article does not assert much on the association of MS and head injury........

    We found no significant association between head injury and MS overall, or in patients with severe injury (as estimated by the proxy of length of hospital stay), or at any time interval between injury and MS. Our findings add weight to the evidence that head trauma does not contribute to the aetiology or precipitation of MS.


    great discussion !

  • Mark Keiter added an answer in Popular Science:
    Searching For A Popular Science Magazine ?

    I would like to publish this article in any platform in popular science - magazine or blog........Any suggestions ?

    Your input would be greatly appreciated. 

    Best Wishes


    Mark Keiter · Naturkunde-Museum (namu) Bielefeld

    Well, the obvious answer would be something like "Scientific American". I have no idea how strict their criteria are, but since it's big league stuff, I would say "pretty strict". I don't even know if you can just submit articles without being invited to do so.

    As for blogs and smaller print magazines - there are plenty out there. With widely varying quality. All I can say is: search them out yourself (especially those which deal with your topics) and carefully check if they have some scientific standards or if they happen to publish junk science all over the place. You'd be surprised how quickly you could be associated with, say, Chemtrail conspiracy nutters or something like that if you publish in the wrong medium.

  • Evelyn Guo added an answer in Machine Learning:
    How to generate ROC curve from svm-light output?
    My svmlight output for binary classification (+1 for true and -1 for false classes) is like
    +1 0.001
    -1 -0.34
    +1 0.9
    +1 055
    -1 -0.2
    I tried generating roc in R using ROCR package. But I found in all examples of ROCR TPR ,FPR and cutoff values were used. TPR and FPR can be calculated from the above data but will get only one value and also w.r to cutoff I am confused. In this case cutoff is -1 to +1 right?
    Can anyone help me how to give the values from the above data for drawing ROC in ROCR package.
    Evelyn Guo · Cornell University

     Hi Hemalatha,

    Could you tell me how did you use SVMLight to get result as 

  • Hein Van Gils added an answer in Direct Observation:
    Are there stidies published on livestock number decline due to permanent/frequent wolf depredation?

    It is possible that in some areas livestock breeders may decreased or stopped livetsock breeding due to permanent/frequent depredation by wolf. Any opinions from direct observations and published papers are welcome.

    Hein Van Gils · Min of Environment & Tourism, Namibia

    A direct observation: a pack of four wolf passes at dawn through a group of grazing horses (about twenty) on their summer pasture; neither wolf nor horse shows distress; horses continue grazing, wolves trot on; in the Apennines horse and cattle roam without shepherd day and night in unfenced pastures. Sheep is another story. Interested? And observations from Africa?

  • Hazim Hashim Tahir added an answer in Men:
    When you hear the words "black and white" what ideas that run in your mind?

    "black and white" are two opposite words include for example the white men and black men it indicates the color of the skin, "black and white" also indicates the good and evil, love and hate, peace and war ........

    Hazim Hashim Tahir · Ministry of Science and Technology, Iraq

    Dear Colleagues,

    Good Day

    When you say " it is black & white" in my country ( Iraq ) , it means it is "crystal clear" or it is "absolutely clear and no one should discuss the matter anymore".   

  • Leona M. Ungerer added an answer in E-Learning:
    How can iBeacons be used in education to transform learning spaces and address individual needs?
    iBeacons is a relatively new technology that has the potential to enhance physical teaching environments. This technology appeared at a time where tablet technologies were already providing teachers with powerful new options for delivering engaging lessons to students in the classroom and beyond. As in the past, where a number of claims have been made about the usefulness and the transformative nature of technology in education, the introduction of iBeacons has already attracted the attention of a number of educators and developers around the world.

    The iBeacon, a bluetooth device, can send signals to smartphones and tablets within a range of 1-70 meters. It does not store data or collect information about users within the range. The question then is how such a technology can be used in education. Alone, it is a useless device, but when combined with tablets or smartphones, the iBeacon can trigger various events. For instance, it can automatically activate messages, images, video clips, apps, eBooks, sounds and links to the internet.
    Leona M. Ungerer · University of South Africa

    Dear Nikos, the embedded post suggests uses for iBeacons in a library environment.

  • Ram Kumar added an answer in Dogs:
    Does anyone know any study about chiropraxis in dogs?

    I need some literature in using of chiropraxis in dogs.

    Ram Kumar · Babasaheb Bhimrao Ambedkar University

    you can contact to Dr Morag McMurray, Ontario, regarding to your work

  • Mohamed Hanafy added an answer in Ovarian Cancer:
    What is the most common biomarker for ovarian cancer?

    Can anyone tell me the most common marker for ovarian cancer?

    Mohamed Hanafy · Najran University - Faculty of Medicine - Al-Azhar School of Medicine

    Another good source :


  • How to simulate wsn in ns3, simple example ?

    wireless sensors network

    Tamoghna Ojha · IIT Kharagpur

    You may look at the following example (after downloading ns-3),


    This example is mainly for ad-hoc network simulations. In this examples, you have to tune different parameters to make the scenario close to WSNs.

  • Devin Hosea added an answer in Gaming:
    Do you consider Internet addiction disorder as a growing problem?

    It is often used as a "free" babysitting service but when lives of our children are damaged, it is not really free.

    In my circle of 'friends and family', there are four sever cases of teenagers damages probably for life. However, I do not have solid numbers. According to Wikipedia, gambling disorder is the only behavioural (non-substance related) addiction included in DSM-5. However Internet gaming disorder is listed in an appendix as a "disorder requiring further study". We should study it.

    Pls help with your expertise.

    Devin Hosea · Princeton University

    I think "internet addiction" is a far too broad and vague term for it to be classified as an Addictive Disorder.  My supposition is that when you talk about "four severe cases of teenagers damaged, probably for life" you are correctly ascribing some addictive components to their behavior online.  But their addiction (remember, there is still no medical definition of "addiction" that is widely agreed upon) is to behaviors (presumably social networking and messaging and so forth) that are ENABLED by constant digital connectivity (esp. via mobile smartphones) but the "addiction" is really to that connectivity and to the communication/content that it delivers.  My view is that these disorders should be considered separately, and should also be viewed in historical context (as in the days before cellular phones, when teenagers would often get their own dedicated phone lines and spend hours in the bedrooms on the phone with friends.  Was that an addictive disorder?).  The internet has just made it easier and more constant, and has created the troubling reality of physical ISOLATION (the "digital cocoon") where virtual interaction replaces "real" social interaction.  The problem, as I see it, is that the current communication/entertainment is ASYNCHRONOUS (for the most part) and thus delivers a very weak version of real social interaction.  Arguably, if the applications for social interaction on the internet were stronger (e.g. true synchronous videoconferencing and the like) the damage to the patient might be lessened.  I agree that current behaviors share some characteristics with real behavioral addiction (obsessive checking of messages) and enable patients to "escape" into a digital cocoon that can be highly isolating at the end-state.  In short, it is a way of escaping from "reality" and spending time in a digital world that lacks the robustness of the real world - in the same way that a substance addiction enables similar isolation and escape.  However, before we go about blaming the "internet" for this behavior, I think we should instead look at the specific use-cases, such as incessant Facebook interaction, and document the harm, and see if these technologies do indeed constitute a "cyberdrug" that have addictive qualities for some patients.  

  • B.T Matemilola asked a question in Hoarding:
    Why do some firms hoard or hold 'excess cash'?

    Cash per share is bigger than stock price in some firms, and this is not a good sign. One of the goals of cash management is to keep investment in cash as low as possible. Moreover, there are opportunity costs of holding excess cash. So, why do some firms hoard or hold 'excess cash'? Your response is welcome.

  • Akilesh Ramasamy added an answer in Medical Devices:
    What issues and potential problems arise as medical devices go wireless?

    What are the potential impactions of medical devices using unlicensed spectrum? Are there current programs examining wireless medical device coexistence in hospitals and other health care facilities? Are there different needs for pre-deployment testing and post-installation monitoring? Are medical device test beds needed, and if so, why? Are there any challenges and/or limitations from using a test bed? Are new issues emerging that make the need for these test beds more or less important consumer use outside medical facilities?

    Akilesh Ramasamy · Consultant Oral and Maxillofacial Surgeon





    Now using multiple wireless devices can cause similar interferences and malfunction (which may be temporary). The possibility exists. Not that this is always the case. With multiple wireless devices being in place, there is a constant risk of interference / temporary loss of connectivity among the devices.

    Wireless technology has it's benefits that it limits the wires around the patient (already the patient in an ICU has multiple connections to and from their body).

    Other potential issues include data theft and loss of privacy.

    I am not an expert on the testbeds area but I am just putting forth some of my opinions/views.

    Testbeds can generate interference environments but the challenge remains to make it realistic and applicable universally which is not possible, as many hospitals / units would have their own unique patterns of interferences due to their construction design, use of devices / mobile phones, nearby mobile phone towers etc; Since we do not have a universally accepted design of a hospital unit (except for the guidelines of course), the environment might be difficult to construct equivalent to real time. Doing the interference study in real ICUs would be risky to patient safety.


    Dr. Akilesh. R


  • Nader Aghakhani added an answer in Materials:
    Does lady's finger help in contolling diabetes?

    In one news paper I came across a news article regarding controlling diabetes by lady's finger. The methodology is described below. Cut a lady's finger vertically. Remove all inner materials seeds etc. and put all scrapped materials and outer layer in about 250 ml water. Store it overnight and use the filtered water in empty stomach. I myself practised it and got good result. Can anybody suggest how these inner materials react with body sugar? or is it a natural source which has similarity with insulin.

    Nader Aghakhani · Urmia University of Medical Sciences

    Dear Dr,

    I sent address the paper.

    You can find it.


    Volume : 3 | Issue : 6 | June 2014

  • Philippa Ojimelukwe added an answer in Cocoa:
    To what extent does the the mucilage on the surface of fermented cocoa beans affect the composition of the dried beans?

    We experimented with the use of washing as a pre-drying treatment in the processing of fermented cocoa beans. We observed significant  improvements in the colour, storage and processing of the dried beans. However, we did not perform chemical analysis to determine whether there are major differences between washed and unwashed beans. There is virtually no formal literature related to the washing of cocoa beans during processing.

    The opinion of other experts will be extremely helpful to us.

    Philippa Ojimelukwe · Michael Okpara University of Agriculture, Umudike

    Washing of cocoa beans after fermentation is not traditionally practiced in Nigeria. I doubt if you can find substantive literature on the chemical composition that will  explain the observation you made (i.e that it improved the quality of the bean). I suggest that you analyze the chemical composition of the washed beans and compare it with the chemical composition of the unwashed beans given similar treatments (except for washing). Cocoa fermentation and drying goes with a lot of chemical changes in the bean. Try to check the changes in phenols, carbohydrates and proteins in addition to theobromine. The analysis will explain the chemical changes that occurred as a result of washing the beans.

  • Is there any recent research in the area of new media convergence and the effect this has on tertiary students' learning?
    With the advent of Web 2 (3 not far) and the prolific abundance and affordability of mobile 'smart' devices can we determine whether this is actually improving the learning of tertiary students yet? Are graduates leaving with skills and qualifications that will prepare them for the new millennium?
    Leona M. Ungerer · University of South Africa

    Dear Maria, the Pew Centre identified three broad generations of technology 'revolution' and suggest that there will be more. We indeed need to prepare our students to function in this changing environment. But, various stakeholders are involved with various levels of skills and access, to there seem not to be generic solutions. Students should probably also be prepared to access the the credibility of information research in a digital world. I enclose a post in this regard as well.

  • Ram Kumar added an answer in Writing:
    Does anyone know some good papers regarding Lyrebird vocalisations, form and function?

    Im writing a report about the Superb Lyrebird vocalisations, however am struggling to find some decent papers explaining the 'hows', and the 'whys', looking at their physical form and function, and how it facilitates their mimicking behaviour, and for what behavioural reason they do this? Any help would be greatly appreciated! Thank you

    Ram Kumar · Babasaheb Bhimrao Ambedkar University

    Please find attached link may helpful for you

    1). http://royalsocietypublishing.org/content/royprsb/266/1429/1609.full.pdf 

    2). http://jexpsciences.com/index.php/jexp/article/viewFile/15783/8083

  • How can we bring together cross section and time series variables in the multiple linear regression model?

    for instance bank data which can be represented in panel and macroeconomic data which is time series?

    Tesfaye Boru · University of South Africa


  • Suresh Suresh asked a question in Resistance:
    Which is the cheapest wafer ?

    1. ( low resistivity or high resistivity wafer )

    2. ( P type or N type)

    3. Criteria for selection of resistivity and type

    4. What type of wafer is preferred for piezoelectric based sensor where silicon doesn't contribute anything except supporting material i.e. cantilever.

  • How can I choose the best experiments from a full factorial design?

    I am handling a set of experiments which have 6 factors and each of them with 3 levels. With a full factorial design 729 experiment need to be done, but 64 of them seems enough for the neural network which need to be trained. My question is, what would be the best way to choose those 64 experiments to cover the whole experiment perfectly and increase the possibility of an acceptable trained ANN (artificial neural network)?

  • Akilesh Ramasamy added an answer in Medical Errors:
    What is the types of medication error?

    Hello, I,m try to discuss all types of medication error to try decreasing these errors as possible.

    Akilesh Ramasamy · Consultant Oral and Maxillofacial Surgeon


    May help. There are various classifications of medical errors which include medication errors as well.

    This draft document may help:


    It is a comprehensive MEDICAL errors reporting system which also includes medication errors.


    Dr. Akilesh. R

  • Surendra Nath added an answer in Lutein:
    Standard values for lutein?

    Friends I m working on marigold lutein extraction and quantification can some body please provide me the standard values for the pure lutein so that my values can be interpolated on it and the amount of lutein present can be quantified.......please the help would be appreciated and acknowledged in the dissertation

    Surendra Nath · Tamil Nadu Agricultural University

    Thanks, very much sir,,,,but i am doing spectrometric analysis for estimating lutein in my samples for which standard values are needed to produce a graph........so do u have any......thank u very much??

  • Brahim Bouali asked a question in Bilingual:
    What exactly happens inside the brain of a bilinguial/trilinguial or whatever?

    Do bilinguals have a twelve string guitar or just two guitars with six strings? Do bilinguals see the world from two different stands or simply see reality from the language that conveys that culture? In other words, are bilinguals smarter than monolinguals?

  • Leonid Sinev added an answer in LaTeX:
    What is a suitable LaTeX editor for mathematicians?

    I am looking for an easy-to-use free LaTeX editor that is friendly to mathematicians who include many mathematical equations in their research articles. Do you have any recommendations?

    Thank you!!

    Leonid Sinev · All-Russia Research Institute of Automatics (VNIIA)

    Sarah, if you are member of a group of mathematicians, you can collaborate on LaTeX papers through online editors:

    Overleaf (https://www.overleaf.com/)

    Papeeria (https://papeeria.com/)

    Sharelatex (https://www.sharelatex.com/)

  • Przemyslaw Kupidura added an answer in Landsat:
    Can we draw the spectral curve for a single pixel in image satellite (just for each bands)?

    Considering that satellites (for example LANDSAT) take a image in multi bands and every bands take a image in spectral range (for example for band 1 of ETM+ sensor it is equal to 0.52-0.45 micrometer) so we should be able to draw the spectral curve for each pixel.

    Przemyslaw Kupidura · Warsaw University of Technology

    what do you mean by "spectral curve for single pixel just for each bands not for all bands"? if you take a single pixel and a single spectral band, all you get is a one value, so no, you can't draw any curve. Spectral resolution of the sensor limits a resolution of the curve you want to draw, so it is not possible to draw a spectral curve for a whole blue band (1) using just ETM+ image. As I wrote before: you have only 1 value there. You need to use a different image, with higher spectral resolution, providing more than 1 spectral band in a range in question (and more than 2 if you want to drive an actual curve). Try some super- or hyperspectral images, like Hyperion (there you have the list of its bands)

  • Hareesh Nagaraju asked a question in Carboxylic Acids:
    Can anybody explain the oxidation mechanism?, how carbon atoms in CNT gets oxidized to carboxylic acid with (Conc.H2SO4 and Conc.HNO3) acid mixtures?

    Oxidation mechanism in CARBON NANOTUBES..

  • Ju Lin Tan asked a question in Plate Reader:
    FITC casein - correlation between fluorescence and protein concentration?

    Hi guys. I have been having some inconsistencies  with the reading of the initial fluorescence value of FITC casein (ex 490 em 520) when I am using it at 1 mM. When I use 1 mM of the substrate, sometimes the plate reader gives me the initial fluorescence of 3000+, but sometimes it gives me 7000+. I was wondering if anyone of you have ever come across this problem, and is able to enlighten me with the reasons as to why could this be happening. Thanks.

  • Surendra Nath added an answer in Essential Oils:
    How to go for extraction of essential oils from Clerodendron inerme leaves?

    Friends, I am willing to try to extract the essential oil ingredient present in the leaves of Clerodendron inerme......the popular hedge plant....in tropics and topiary......i have tried hydrodistillation and ethanol based extraction but finding it difficult to seperate it from the solvent used.......

    Surendra Nath · Tamil Nadu Agricultural University

    Thank u very much Rajeswara Rao sir.......i appreciate it alot.......

  • Lifeng Kang added an answer in Neuroscience:
    Does anyone have experience with the Journal of Visualized Experiments?
    We are currently debating about subscribing to JoVE in the categories "Neuroscience" and "Behavior". Could anyone comment on the overlap of both categories or the usefulness of the individual categories or even articles? So far "Behavior" only contains 39 articles. Could it be supposed that JoVE is growing? I have seen some colleagues publishing there, but it still seems to be off the typical pursuit of impact points. Could it be supposed that JoVE will receive an Impact factor in the future?
    web: http://www.jove.com/
    Lifeng Kang · National University of Singapore

    I'm now in the process of publishing a paper with JoVE.

    Apart from the high cost, the real concern now its impact factor. It is absolutely critical for this Journal. JoVE is one of a kind and with lots of potentials. But without an impact factor it will not go very far.

  • Pavan Vadlamudi asked a question in Weather:
    Masters mini-THESIS direction?


    I am taught masters student in Software development. I am looking for direction for my mini-thesis.

    Topic given/chosen is weather forecasting “predict what the value of weather parameter for a given station will be, based on the observed weather parameters for the others stations.”

    I have data and I am good in C#. Should I choose a algorithms such as Bayesian Networks or “Weka 3: Data Mining Software in Java”