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  • Isura Nagahage added an answer in Drought Stress:
    What are the best methods to obtain preliminary data on drought assay by using arabidopsis mutant lines?

    We have generated multiple mutant lines (ATAF family) to see some drought stress response in order to undestand some protein interaction. Could you please advise and suggest me some methods to obtain preliminary data regarding drought stress assay?

    Isura Nagahage · Saitama University

    Thank you so much Sajan for your explanation. Definitely it will helpfull for me for my primary screening. I'll follow your link .

  • Daniel Page added an answer in Applied Mathematics:
    What textbooks do you suggest for an introductory course about dynamic programming and its applications (specially, in optimization)?

    I need a textbook suitable for teaching dynamic programming and its applications for undergraduate applied mathematics students. The textbook should cover most aspects of DP specially its applications in optimization.

    Your suggestions will be  appreciated.

    Daniel Page · The University of Western Ontario

    Is this lower or upper end undergraduate course level?  (i.e., 4th year?  2nd year?)  This will make a huge difference on what book I'd recommend personally.

  • Toqir Rana added an answer in Topic Modeling:
    How good are topic modelling techniques like LDA for finding aspects for opinion mining on short text?

    To perform aspect based opinion mining we first need to extract aspects or say topics for a document ( in this case short text like online reviews / tweets ). Will techniques like LDA or multi grain LDA give up to the mark performance for such kind of topic extraction?

    Toqir Rana · University of Science Malaysia


        There are number of research papers for topic modeling in sentiment analysis but these are on online reviews. Most of them used LDA based techniques. Here are some

    Chen, Z. & Liu, B. Topic Modeling using Topics from Many Domains, Lifelong Learning and Big Data Proceedings of the 31st International Conference on Machine Learning (ICML-14), 2014, 703-711

    Chen, Z. & Liu, B. Mining topics in documents: standing on the shoulders of big data Proceedings of the 20th ACM SIGKDD international conference on Knowledge discovery and data mining, 2014, 1116-1125

    Chen, Z.; Mukherjee, A. & Liu, B. Aspect extraction with automated prior knowledge learning Proceedings of ACL, 2014, 347-358

    Also try to visit Dr. Bing Liu's site there are number of papers available for topic modeling for aspect extraction, survey and books. Hope this will help.

  • Renann Baldovino added an answer in Simulink:
    How to connect Gizduino hardware to MATLAB Simulink?

    Any tips and video tutorials from our experts will be greatly appreciated. Thanks.

    Renann Baldovino · De La Salle University

    Thank you Mr. Vladislav. I will try to check and view on those links you provided.

  • Susan M Walker added an answer in Overdose:
    Does anyone know if definition (group) suicide due to self-harm regarding causes of deaths by ICD-10 is really inappropriate to use in a study?

    We are trying to study the differences in causes of death due to suicide (ICD-10: X60.0 - X84.9) between illicit drug users in contact with drug treatment services and those without from national General Mortality Register (GMR), the underlying cause of death is encoded according to ICD-10, selected underlying cause of death linked to external causes of injury and poisonings. Data from GMR are regularly reported to the WHO.
    As we are talking about illicit drug users, where suicide by overdose is relatively frequent we would like in our study to introduce concept of direct cause of death-suicide (by overdose, poisoning with psychoactive substances) and indirect (where death-suicide is not a direct consequences of drug) according to EMCDDA. Considering this and causes of death by ICD-10 (among poisonings e.g. X62 Intentional self-poisoning by and exposure to narcotics, while among self- harm e.g. X70 Intentional self-harm by hanging, strangulation and suffocation) in our opinion should be appropriate to divide suicides in direct by self-poisoning (overdose) and indirect those by self-harm. Unfortunately one of  experts (in the field of suicide) insists that group of suicide by self harm is not acceptable as per definition of WHO self harm could not finish in death.

    Thank you in advance for comments and suggestions.

    Susan M Walker · Queensland University of Technology

    In the ICD-10, the block of codes that reflect self harm (X60-X84) includes suicide. The block includes both completed suicides and attempted suicides, as well as incidents of self harm. There is an inclusion note in the Tabular list (volume 1) that states:

    Intentional self-harm
    Includes: purposely self-inflicted poisoning or injury
    suicide (attempted)

  • I want to divide my respondents into two groups. What formula should I use for dividing 5 Likert-Scale into two groups?

    Two groups : Tourists with Low destination image and tourists with  High destination image. I used a 5 Likert-Scale for my questionnaire, where the participants could either strongly disagree, disagree, neither agree nor disagree, agree, or strongly agree .

     A high Destination image indicates that tourists perceive the positive attributes of the destination and a low Destination image indicates negative attributes of the destination.

  • Sujeet Singh asked a question in Microbial Culture:
    Is there any method (Other than using Peroxidase enzyme) for detection of glucose oxidase enzyme produced from microbial culture?

    Is there any method for detection of glucose oxidase enzyme produced from microbial culture? The typical method using Peroxidase enzyme is very costly. Can anybody tell us any quick and inexpensive protocol for qualitative and quantitative estimation of Glucose oxidase enzyme produced from microbial culture.

  • sapto nugroho Hadi asked a question in Spectroscopy:
    Metabolomics approach for microbial respond to environmental condition?

    Dear all, please let me know which the best instrument for doing metabolomics study of microbial respond to the environmental condition: Gas chromatography-mass spectroscopy or Liquid chromatography-mass spectroscopy? or maybe any other instrument?  Thank you.

  • Learing R and Matlab for Econometric analysis, How for is it helpful?

    Hello all,

    Recently i have been spending some time to learn R and Matlab for econometric analysis but I would like to know how far is it helpful in data analysis when compared to GUI software like SPSS and etc.., 

    Andrew Messing · Harvard University

    I would generally agree with Roman Matkovskyy. There's no point in learning MATLAB if most of what you will be doing can be done fairly easily in Excel. Likewise, there's little point in using Excel if your lab or department or business provides you with a license for SPSS (which is basically Excel with a lot more ability to not understand what you are doing but report significant results because you plugged in numbers and SPSS said your p values were .01 or something).

    In particular, if your choice is between MATLAB and R, the first thing to consider is that R is free and MATLAB is extremely expensive. I would only consider it if you either 1) have a lot of cash to throw around or 2) your department, lab, etc., has an institutional license you can use.

    If you CAN use MATLAB (i.e., you can afford it or it is provided for you), then there are perhaps two major things to consider. First, R is a statistical language/software package. MATLAB can certainly run any statistical tests that R can, and has most of the statistical methods/tests/models that R has built in. However, it is designed more for computational sciences, engineering, and so forth. The name comes from "matrix laboratory", and there really isn't any software out there superior to MATLAB when it comes to exploiting the power of linear algebra with ease. Additionally, the GUIs available for R (RExcel, R Commander, RStudio, etc.) are fairly limited, especially when compared to MATLAB, which in addition to being the perfect balance between a programming/scripting environment has a large number of toolboxes/apps that run the gamut from a neural network tools and fuzzy logic tools to a slew of computational biology tools and of course an Econometrics Toolbox.

    Also, because the environment is so much more user-friendly, you don't have to spend time e.g., writing the code for plots, then changing it and running the same plot again, then trying out another by writing more code, etc. Once you have your variables you can use graphical user interface plot functions (MATLAB has many).

    However, MATLAB is again more a computational software program than a statistical one. As it is proprietary, there isn't nearly as much support. So even if you have access to MATLAB, if you are only or mostly concerned with statistical analysis, R is probably better.

    A note, though, about Python. SAGE mathematics is a free-ware scientific computing software package that brings together many, many free scientific computing, statistical, and computational packages such as SciPy & numpy. However, it's a pain to use if your operating system is windows unless you know your way around emulators.

  • Rashmi Kulkarni added an answer in Mitochondria:
    How is MitoTEMPO treatment given? Added along with the stress inducer or separately after the assay?

    I am treating C2C1 myotubes with free fatty acid and would like to measure mitochondrial specific super-oxide production. I will be using MitoTEMPO for specificity. I have couple of questions regarding MitoTEMPO treatment. How long MitoTEMPO treatment should be given (I didn't get much information about this, information about the concentration is mentioned)? Secondly, I found that in some references MitoTEMPO is added along with the stress inducer and MitoSox at the final hour of the stress inducer treatment NOT after completion of the treatment. What is right way to do it ?? Any suggestions/ideas/references on this ? Thanks !

    Rashmi Kulkarni · Indian Institute of Science Education and Research, Pune

    Hi Nai-Kei,

    I tried your method of 2x pre-loading but surprisingly I am getting almost equal or higher ROS production in TEMPO treated wells than untreated. I used phenol red free medium for the treatment (which is 18 hours long treatment with fatty acids). What might be wrong ??



  • Joshi Niraj added an answer in microRNA:
    How can find out the UTR of the gene ?
    I want to know how find out the utr of the gene for binding of micro RNA
    Joshi Niraj · CHU de Québec

    I just confirmed something, you could go to NCBI nucleotide to look for your GOI. Then, click on CDS and it gives you complete information about coding DNA with UTRs. These UTRs exactly matched with one shown in UCSC. I just cross checked because it was not mentioned in NCBI, however was logical to think that!

  • Oriobosa Awanle added an answer in Pipeline:
    How do you calculate the impact forces of icebergs colliding with offshore pipelines?

    How to calculate the impact forces of icebergs colliding with offshore pipeline.

    That is, for any arctic environment.

    Oriobosa Awanle · Cranfield University

    thanks very much  this is a good concise research. Though in this literature I am not really considering the interaction with the soil mechanic. The question based on the impact force the Iceberg collide with pipeline and this is really static mechanism.

    Once again thank you for your contribution

  • Saqib Kabeer added an answer in Segmentation:
    Is it possible to extract a region based on its area??

    I am  working on segmentation,my segmented image contain 2 regions which have same intensity,so is it possible to extract the region of interest based on its area??

    Thank you

  • Vinod Kumar added an answer in Precipitation:
    How to analyse serration in flow curve w.r.t. strain-induced precipitation?

    Various types of serration are observed in a flow curve during hot compression testing. The serration may be due to strain-induced precipitation. If yes, what is the best way to analyse the serrations and arrive at some useful findings from practical application point of view.

    Vinod Kumar · Steel Authority of India Ltd (SAIL)

    Thanks Zisman and Mohamadizadeh for your quick comments. This work is related to 3% Si steel where MnS is exepcted to precipitate during hot deformation. We have observed alternate positive and negative serrations at a strain rate of 10/s and not at 0.1, 1 or 100/s strain rates through the entire temperature range of 950 to 1150 C (not very prominent at 950 C). We shall analyse the flow curves as suggested to revert back.

  • How can I set up serial communication between Atmega16L and PC?

    I connect serial tx pin no 18 to RS232 converter and give it to PC. Hyperterminal should display transmitted string but it is not coming. RS232 is working as I checked loopback. Atmega is also working as I check LED blinking code in it and its working. I check my code for string transmission in other platform and its working so code is also correct. I changed all baud rate settings and I also change crystals but unfortunately its not working.

    Faiz Asraf Saparudin · Universiti Teknologi Malaysia

    Are you using RS232-USB on your PC? I think you should make sure the correct driver is installed (I'm assuming you're using Windows). Another thing, you might want to check the supply voltage on your embedded circuit, if I'm not mistaken RS232 swing up to +-15V rather than 3.3V or 5V on your microcontroller.

  • Pat S. Chavez, Jr. added an answer in 3D Printing:
    Are there any morphological filters that differentially dilate objects?

    I'm going from CT data to 3D printing of pediatric skull models. We need to increase the thickness of thin tissues to keep the printer happy. Does anyone know of a morphological operation/algorithm or MatLab script which will dilate thin parts of the object while ignoring other areas? I imagine this is best done before converting the object to a mesh, but am open to solutions either working with the original CT data or post-processing after converting to an STL.

    Pat S. Chavez, Jr. · Northern Arizona University (retired USGS)


    I come from the remote sensing community (satellite, airborne, and acoustic shipborne imaging) with about 4 decades of 'experience'.  I've had an interest in the use of some of the image processing and analysis methods used in remote sensing within the medical imaging field; I realize that I know very little about the current state of the art within the medical imaging field so I want to say sorry ahead of time if I state the 'obvious' to you and others. 

    What I would do is apply a small High Pass Spatial Filter (HPSF), stretch all the pixel values in the original image that are within 1.5 to 2 std dev in the HPSF to zero (which would leave the 'thinner lines / features in the original image, and then thicken the lines/pixels that are left, and then merge it back with the original.  In the remote sensing field we are use to working with images that have 4000 by 4000 or more pixels which I think is not the case in the medical imaging field, so I would think that a filter window size of 3 by 3 to 5 by 5 might be a good starting point (I would have to see an example and know how many pixels are in the image).

    Again, sorry if I 'missed' the mark because of not knowing what can and can not be done at this staage in your field.......... I am willing to learn.


  • Mahmoud S. Mahmoud 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?


    Mahmoud S. Mahmoud · Auckland University of Technology

    In Big Data and databases the idea is the data is dynamic and to intense to persist, so rather the concept is to persist the queries, since the questions we seek from Big Data are relatively static in comparison to the Big Data. Essentially these queries are long running, continuously returning results from Big Data. This result may be persisted as it is usually a very small fraction of the Big Data.

  • Ahmad Nobah asked a question in 3D Printer:
    How to prepare Hydroxyapatite for 3D printers? and how can I purchase Hydroxyapatite?

    We want to use Hydroxyapatite for 3D printing.

    What we would like to know:

    1. How to prepare the Hydroxyapatite powder for 3D printers?

    2. Is there any material that has the same atomic composition as Hydroxyapatite that also can be used for 3D Printers?

    Thank you

  • What parameters one should consider while designing furniture for autistic children?

    I want to design furniture for autistic children so i want do know what features should be there in the study table, chair of the autistic children.

    Napoleon Ono Imaah · Rivers State University of Science and Technology

    The design of furniture for autistic children should consider such children as individuals in private homes as well as individuals in populated public places amid a mixed multitude. The fact that autistic children adjust adversely to change of environment, furniture and toys, etc calls for a synchronization of furniture design of places where the autistic child spends most of the time.

    The design of furniture for autistic children should commence only after a thorough analysis of the individual and collective need of the autistic children. Although autistic children have common characteristics: they have highly divergent individuality. This distinctive traits call for customized designs. However, mass production is permissible in public places, using the common characteristics.

    The hyperactive dynamics autistic children call for caution while designing furniture for them. The furniture should be robust and but not hard. The edges and surfaces should not be rough or sharp. The surfaces should not be slippery, sticky, glassy, greasy, etc. Furthermore, the materials must neither poisonous nor chewable. The furniture should not be overtly ornate or excessively colourful. Otherwise, a violation of these precautionary measures coud trigger off hyperactivity and allergic reactions

    Climbing and falling from heights is a frequent pastime of autistic children. Thus, high furniture with possibilities and parts for dangerous acrobatic adventures must be avoided.As the saying goes to one that is down needs fear no fall

  • Shiva Shankar added an answer in Circuits:
    I need a circuit or device that can phase shift voltage of a transformer by certain angle that i input ?

    This circuit or device is essential for phase shifting the voltage through desired angle Theta .

    Shiva Shankar · Sreenidhi Institute of Science & Technology

    in internal construction of a transformer when we will give ac input the output voltage will phase shifted by 180 degrees.

  • Raj Kumar added an answer in HFSS:
    What is thickness of a 2D sheet used in high frequency structural simulator (HFSS)?

    What is thickness of a 2D sheet used in high frequency structural simulator (HFSS)? The sheet is usually assigned as copper.

    Raj Kumar · VIT University

    thank u @Leticia Alonso González

  • Lasantha Rathnayake added an answer in Calculations:
    How to use the output of low level of theory calculation, as input for a higher level of theory, in details please?

    i read that i can use the checkpoint file of low level method to save time and getting a better accuracy.

    Lasantha Rathnayake · Tennessee Technological University

    There are several ways to get low level information to use in high level theory as mentioned by others above.  One other simple way is just copy  the last coordinates set named "Standard orientation" at the end of Gaussian output file (just before the "optimized parameters" section and use them as input coordinates for your high level calculation (you might need to do some MS excel editing before that to get rid of unwanted columns). This solution is good only if you are a novice to Gaussian like me!! or if you don't have Gauss View.

  • Zhongwei Qu added an answer in Fiber:
    Is there a method or chemical compound can kill or silence neurons through acting on soma but do not damage or impact the pass by fibers?

    is there a method or chemical compound can kill or silence neurons through acting on soma but do not damage or impact the pass by fibers?

    Zhongwei Qu · Institute of Neuroscience

    Thank you very much! It is a good method to solve the problem and you recommended me a good paper.

  • Seng Neon Gan added an answer in Adhesion:
    What is an alternative to peel test for adhesion?

    Hi all,

    we are trying to quantitatively compare the adhesion characteristics of surfaces (polymer and metal). For that, we use Instron 5544A and perform a peel-test. That means, we scratch a small section of the polymer and let the machine peel it Toff.

    Though, for some of the samples that we prepared, the adhesion between the layers is so strong that we can't even scratch the polymer and start the peel test. Strong adhesion is desired for our case; but we need to show some data to prove it. Do you have any suggestions to quantify/prove the adhesion superiority for such cases (eg. UV treatment before test, using a different test equipment etc.)?

    Thank you,


    Seng Neon Gan · University of Malaya

    Peel adhesion test is relevant for evaluating the performance of pressure sensitive adhesives.  In the case of polymer firm coated onto a metal surface, it might be difficult or not relevant to carry out the peel adhesion test by method such as ASTM D3330 Peel Adhesion Testing.

    To evaluate the relative adhesion strength of different polymer coatings on a metallic surface, you may try “Cross Hatch Adhesion Test” according to ISO2409, or AS1580-08-04, or ASTM D3359B Standards.

    Alternatively you may try an “Indentation Adhesion test” or “Bending Adhesion test”  such as ASTM D4145 for determining flexibility and adhesion of coatings on prepainted metallic substrates.

  • What is the reason for increasing storage modulus and decreasing glass transition temperature at 0.5 wt% of nanoplatelets composite?

    i considered two different type of composites one is nano platelets added FRP composite and other is only FRP composite. after done DMA test my results came like glass transition temperature of nanoplatelets addedFRP  is lower than than the FRP composite but Storage modulus is getting higher for Nanoplatelets added FRP composite. what is the reason?

    Shahryar Malekie · Atomic Energy Organization of Iran

    Maybe for high thermal conductivity of Fibres and also for forming percolation networks at 0.5 wt% ,glass transition temperature of composite occurred at lower values.

  • Special relativity: a big Heisenberg's uncertainty principle?

    If you know the coordinates for one referential, you can only know the speed of the other. If this is true, are the Lorentz transformations incomplete? Or do they resolve the Heisenberg's uncertainty principle?


    Debajyoti Sarkar · The Inter-University Centre for Astronomy and Astrophysics

    "I propose you to measure first the velocity, then use LT to find the position of it."

    When you measure velocity, the  state collapses to a momentum eigenstate. Hence it is not possible to know the position of the particle as it is projected all over the position space.
    Secondly, how can you find position just by measuring velocity? Two particle at different position can have same velocity.

  • Krishnan Umachandran added an answer in Sculpture:
    Do you know any masterpieces of art which are devoted to anti-war themes?

    One of the main tasks is to cultivate peacemakers. Anti-war arts (painting, sculpture, literature, music, photo) can be helpful in upbringing future generation. Cultivating a culture of peace through awareness of genius message (implicit and explicit) is important in schooling. We are going to research the sources, organize the conference and stage one of the creative works. We will be thankful for every contribution.    

    Krishnan Umachandran · Professor

    PABLO PICASSO's encounter with Surrealism in the mid-1920s, although never transforming his work entirely, encouraged a new expressionism that had been suppressed throughout the years of experiment in Cubism and subsequently during the early 1920s when his style was predominantly classical. This development enabled the starkly angular imagery of Guernica (1937), the century's most famous anti-war painting.

  • Kisalaya Basu asked a question in Regression:
    Is it ok to have log transformation in difference-in-differences regression?

    Is it ok to have log transformation in different-in-difference model? It seems like we cannot as it violates the additivity assumption. Am I correct?

  • Tahereh Jafary added an answer in Cuvette:
    Does anyone know how to fix the matter with floating particles in COD test?

    Hi All, I will appreciate if anyone could share his/her experience or any info about this matter with me. I am doing COD test on some industrial waste samples. to make it economic, i make reagents solution by  myself by following the standard method. after all sample and standards preparation, two hours digestion in oven , and cooling down to ambient temperature, when i was gonna transfer samples from cod vials  to spectrophotometer cuvette to read the absorbency, the problems with floating particles in cuvette comes out (sedimentation). no one has faced this matter and if you know the reason or anyway that can fix it. Actually i am not using the ready COD vials with solution which is in market (like Hach) and i dont have COD spectrophotometer that be able to put COD vial directly inside to read the absorbency. i just have a general use spectrophotometer that just support its own cuvette. 

    Tahereh Jafary · National University of Malaysia

    Thanks Dr Azizul, the floating particles form when i transfer the solutions to cuvette, before that they are  totally clear. I tried to read it after one day and just take 2ml of each sample with  pipette without moving the COD tubes.I Could read the absorbancy then. but am afraid about changing the COD after one day and am curious about the reason. do the compositions inside samples interfere with the reading or any other reason?