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  • Gianpiero Amanzio asked a question in Time Series Analysis:
    Hi everyone, I want to apply time series analysis (spectral density) on to my dataset (spring discharge). Someone could show me how to do that?

    Specifically, I want calculate the spectral density in matlab enviroment.

  • Jim Holohan added an answer in Longitudinal:
    Has anyone come across a definition for longitudinal research as it relates to practice?

    Has anyone come across a definition for "Longitudinal Research" as it relates to practice?

    I have come across a couple that relate to process with an emphasis on change over time i.e.

    "Research emphasising the study of change and containing at a minimum three repeated observations (although more than three is better) on at least on of the substantive constructs of interest."  Polyhart & Vandenberg (2010).

    "Those techniques, methodologies and activities which permit the observation, description and/or classification of organisational phenomena in such a way that process can be identified and empirically documented."  Kimberly (1976).   Where process is any sequence of changes in organisational variables.

    All comments welcome.

    Jim Holohan · Limerick Institute of Technology

    Thank you for your responses, which have been very helpful.

    Jim Holohan

  • Sambhaji Dnyaneshwar Shinde asked a question in Geoinformatics:
    What are the specific applications of geoinformatics in life sciences?

    I want to know applications of geoinformatics in zoology, botany, and environmental sciences.

  • Atai Rabby added an answer in Sequence Analysis:
    What is the best software for sequence alignment?
    Most sequence alignment software comes with a suite which is paid and if it is free then it has limited number of options. Can anyone tell me the better sequence alignment software.
    Atai Rabby · University of Dhaka

    MEGA would be best suitable for you, if you are looking for advance options.

  • Franck Courtès added an answer in Cell Culture:
    Dot-like particles in cell culture: is it contamination or not? No change in pH, turbidity, cell morphology and cell growth.
    I am experiencing some strange problem in some adherent cancerous cell lines. I have observed that these dots only adhered to cells for first 2 days after passaging, but these dots then start to become visible in the media also. The number of dots increases after 3-4 days if cells are not sub-cultured.

    The cell lines grow properly, there is no change in pH of media or turbidity. I changed FBS, Trypsin, Media etc. i also thawed frozen vials but the problem still persists.

    After washing 4-5 times at 500 RPM the number of dots decreases significantly but after culturing the dots start to appear again. We did DAPI for mycoplasma but it came Negative. Treated with PLASMOCIN for 1 week.
    Franck Courtès · King Mongkut's University of Technology Thonburi


    Thank you for all your messages

    I do face similar situation with Vero cells.

    So in the end could you find the reason of these black dots like particles?

    Thank you very much for your time and consideration.

    Best Regards

  • Mohammad Israr Khan asked a question in Inclusive Growth:
    Can India make an act on land acquisition which balances the diverse interests as well as ensures the national cause of an inclusive growth? How?

    land acquisition debate.

  • Jamal Saeedi asked a question in 2 Dimensional:
    How can we identify 2 dimensional multiple signal direction of arrival using phase interferometry method?

    Is there a good reference for this purpose?

  • Vignesh Vicky asked a question in Pollutants:
    Which air purifier should we use to purify the pollutants near a construction site so that the near by people would get purified air.?

    need info the type of airpurifier that purifies pollutants from automobiles and construction sites in a large scale.

  • Balasubramani pk added an answer in Stem Cell Culture:
    Is it feasible to obtain 100 Million Mesenchymal Stem Cell in a 2 Layered Cell Factory?

    I would be using 2 layered cell factory (1272cm2) for Mesenchymal stem cell culture.

    Source - P1 Umbilical cord Mesenchymal Stem Cell.

    If it is feasible to culture and arrive at the  magical number (I100 Million mesenchymal stem cell ). what would be the ideal media to use, Supplement ( FBS % and bFGF concentration ) and Seeding density ?

    Balasubramani pk · Cryo Stemcell pvt ltd

    Dear Alex,

    Here are my results from 4 different 2 layered cell factory !!

    Cell Factory #1  - 77 million

    Cell Factory #2 - 63 million

    Cell Factory #3 - 56 million

    Cell Factory #4 - 43 million.

  • Michel Tabart added an answer in Cell Membrane:
    What agents induce permeability/cell membrane penetration of molecules; and at which pharmacological non-toxic concentrations?

    Can anybody inform what agent(s) induces permeability/cell membrane penetration of molecules; and at which pharmacological non-toxic concentrations? Best regards

    Michel Tabart · Sanofi Aventis Group

    Bonjour Saliha,

    Le Sodium Dodecyl Sulfate est un agent qui induit la pénétration des molécules à travers la membrane. Il est notamment utilisé, comme tu sais, dans le test SOS, comme décrit dans cette publi:

    Mutat Res. 1991 Feb;252(1):51-60.
    Sources of variability of the Escherichia coli PQ37 genotoxicity assay (SOS chromotest).

    Sa toxicité est décrite dans l'article suivant: http://www.ijabpt.org/applied-biology/toxicity-of-sodium-dodecyl-sulfate-in-fishes-and-animalsa-review.pdf



  • Dirimanov Stoyan added an answer in B-Tubulin:
    Can you help me with unexpected band in western-blot?

    Hello and thank you,
    I used Allprotect Tissue Reagent to stabilize human kidney samples. After some months I extracted DNA, RNA and protein with the AllPrep DNA/RNA/Protein Mini Kit from Qiagen. Now, I have started to work with the protein extracted with the kit (precipitation) and solubilized with 8M urea. I tested the proteins with a b-tubulin antibody and they work perfectly well, but when I started to do the western blot with other different antibodies, I found an unexpected band at 100 kDa aproximately in all the blots. The only difference between the b-tubulin antibody and the rest of antibodies is that the first one was incubated with 5% milk and the rest with BSA.
    Do you know if the protein extraction method can have something to do? I have tried with six antibodies (from rabbit and mouse) and always is the same. Do you think that the BSA can interfere anyway? Tomorrow I am going to test it, but I would know if you have some similar data. Thank you.

    Dirimanov Stoyan · University of Wuerzburg

    Laurence, thank you very much for the positive comment.

    I think that the unexpected band is likely to represent the protein of interest (better control with a blocking peptide as Laurence mentioned, to be sure) - the lanes seem to be of similar size with those of expected one... I think the reason can be: 1. this band is a result of posttranslational modifications (lysate of cells expresing those proteins can also be tryied as a control); 2. there are any modifications after extraction (oxidation, building an aducts with non-polymerized acrylamide- http://www.ncbi.nlm.nih.gov/pubmed/15935323) 3. proteins are not separated properly on the molecular weight (trying different gels and I would say maybe also blotting system...)

  • Salvatore Chiavarini added an answer in Gas Chromatography :
    Hi can anyone advise me how to minimise peak tailing factor in GC methods ?

    At present Tf is 2.5 looking less than 2.0.

    Salvatore Chiavarini · ENEA

    Too many factors come into play in determining the peak shape/tailing (gas flow/linear velocity, solvent/column phase, injection temperature, injection mode, T program, column installation, column/liner activity, analyte properties...just to name a few..).

    In order to give you some real advice beyond common knowledge, we definitively need more info about your specific setup and analytical work

  • Valbona Aliko added an answer in Blood:
    Does anyone have any idea what we found in the serum sample? It's white, soft and appeared just after centrifugation?

    The blood comes from a pregnant woman. And was not lipaemic.

    Valbona Aliko · University of Tirana

    Can be either albumin or candida infection.

  • Vinay Patel asked a question in Silicone Oils:
    Which solvent is used for hardening of microparticles formed by W/O/O emulsions?

    I am using dichloromethane+acetonitrile and silicone oil. I am using PET ether for hardening but the particles are forming a agglomerate after the stirring is stopped.

  • Gerhard A. Schroeder added an answer in Financial Mathematics:
    Is the Black-Scholes formula an invalid optionpricing model?

    I would like someone to discuss the following hypothesis:

    The Black-Scholes formula is not a valid optionpricing model.

    When backtesting S&P stock options using B&S and the real volatility (= standard deviation) ex post the costs exceed the payoffs by 4 percent, using the VIX (=Volatility of the S&P500) by 26 percent. 

    The method is: buy fictitious call options day by day over 15 years  at the money and at the price of fair value - compare the sum with the cumulated payoffs. The rationale:

    The payoffs should somehow match the amounted procurement costs at least.

    (For puts it's even worse - 18 / 46 percent overpricing.)

    Any comment appreciated.

    Gerhard A. Schroeder · Private Research

    Added a working paper that contains more detailed experiments applying the BS-formula to S&P and VIX data. 2 questions:

    o Does the revers application of B&S induce a systematic error with a tendency to increase the index volatility?

    o The payoffs of options on a broad portfolio like S&P don't match their fair value at emission time. Is the B&S formula still applicable - even for financial reports and balance sheets? 

  • Atai Rabby asked a question in ps:
    What is the significance of Positively selected genes ?

    Exact points of my question are 

    1. Why should one indentifty selected genes ?

    2. How valuable a data if we identify selected genes ?

    3. What would be further research questions after identification of PS genes

    4. What are the biological significance of positive selection. 

  • Naoufel Boulila added an answer in Software Engineering Tools:
    Are there any meta-communication model for Software Engineering Processes?

    As the nature of human errors depends on the specific properties of the decision-maker and the context of IT project processes it seems that a kind of meta-communication model may be useful for increasing quality of SE processes in the sense of avoiding human errors. Are there any research performed on meta-communication within Software Engineering processes? Thanks in advance!

    Naoufel Boulila · Siemens AG

    Dear Boriss, the meta model looks good. however, i would consider stakeholder requests that translate into new and changing requirements as it happens in the real world ( role Stakeholder, use case "request requirements" or so). Also rationale management for decision making.

    i attached the paper "Communication Metrics for Software Development"  written by my doctoral adviser prof. Bernd Brügge and and my ex-colleague Allen Dutoit. That might provide you with more insights and directions.  Allen wrote his PhD dissertation called " The role of communication in team-based software engineering projects"  from the CMU, which might be very interesting, but unluckily i couldn't find it online.

    hope it helps.
    take care


  • Heinrich Theodor Vierhaus added an answer in Logic Synthesis:
    Are there some classical and latest papers and books about Totally Self-checking Circuit(TSC)?

    I'm very interested in a kind of circuits named Totally Self-checking Circuits, (TSC), and I want to know everything about TSC Logic Synthesis and Design Method, but I can't find enough papers or books about TSC. So , please, are there some classical and latest papers and books about Totally Self-checking Circuit?Thanks.

    Heinrich Theodor Vierhaus · Brandenburgische Technische Universität Cottbus

    I believe papers and books by E. Sogomonyan and M. Gössel will help you most !

  • Masafumi Kamiyama added an answer in Polymer Chemistry:
    How can I infiltrate a polymer in to PhC air holes of dimension 200nmX150nmX10 microns in silicon ?

    the hole is rectangular in shape and 10 microns deep.

    Masafumi Kamiyama · mntc

    "infiltrate" means filling up?

    if so, how about using emulsified polymers. you can get the emulsified polymers dispersed in a medeum, like water or organic solvent, by emulsion polymerization.

    Imersing the sample in the dispersant, the polymer easily deposit on the surface of the sample, and wipe out an excess polymer.

    Affinity of the polymer and silicon is important, using comonomer such as 3-(trimethoxysilyl)propyl methacrylate for example enhance the affinity on sililcon. Or using silicon containing macromonomer as surfactaning for emulsion polymerization also available for enhancing the affinity.

  • Nina Baur added an answer in Cross Sectional Survey:
    Can we add 50% more sample size in cross sectional surveys? If yes! how can we justify it?

    With a prevalence of 11% the calculated sample size was 150. Can I add 50% more sample size to enroll more respondents?

    If yes! how can we justify it?

    What are the conditions where we need 50% more sample size?

    Nina Baur · Technische Universität Berlin

    The problem is not the sample size - you can also draw a second random sample. The problem is 

  • Laszlo Jicsinszky added an answer in 1H-NMR:
    What may be the reason that a column separated flavonoid further confirmed by TLC, shows some impurities in 1H-NMR(DMSO solvent) peaks?

    I have confirmed a single spotted compound (having brown colour, so we suggest it may be flavonoid) on TLC, then used column chromatography to separate it, and it was further confirmed by TLC as single spot using acetone:ethyl  acetate(1:2) as solvent system. Now the 1H-NMR is confirming some impurities, as the doublets, triplets etc are not of good standard (in terms of their ratio).

    Laszlo Jicsinszky · Università degli Studi di Torino

    Residual solvents? You did not mentioned in which region are the found impurity signals.

  • Mario Guevara Bonilla added an answer in Sustainable Forest Management:
    Do you know of publications on tropical timber tree growth in Mexico and Latin America?

    It is assume that sustainable forest management is based on tree growth, however there is little data about it, but my be some studies are on the going.

    Mario Guevara Bonilla · Costa Rican Institute of Technology (ITCR)

    Search for tropidry studies. They are currently working with tropical dry forests

  • Markus Lukacevic added an answer in BLOCKS:
    How to use UMAT subroutine with UDMGINI and XFEM?

    Dear All, 

    I have written UMAT subroutine for GTN damage, to simulate Ductile crack growth with cleavage. 

    I am also calculating Weibull simultaenouly. However, as unfortunately I came to know that element deletion wont work with UMAT, but many researchers have reported using UMAT for failure simulation.

    I have few question 

    1. If i degrade an element, will that element be out of calculation? i.e. will the crack grow?

    I dont think so, but I may not know if it can happen!!

    2. Therefore, I am using UDMGINI with UMAT along with enrichment of XFEM, but still I get error such as, PENALTY STIFFNESS to be augmented with Pressure overclosure or something, whats the way out? please help

    3. Finally to make GTN damage nonlocal, I have to use common blocks for elements info, but I dont have any idea about common blocks, can somebody help me with some examples of common blocks especially used in context of element manipulation.

    Thanks to all in advance.

    With regards,

    Markus Lukacevic · Vienna University of Technology

    You defined "Surface Behavior" twice, try deleting line 5053.

  • Shabi Shimny P.s added an answer in Health Insurance:
    Are there any references related to getting reviews on health insurance?

    Dear All,

    I am working on measuring the perceptions of policyholders towards health insurance schemes. Kindly suggest me some references where I can get reviews related to health insurance.

    Shabi Shimny P.s · Bharathidasan University

    Thank you Sir,

    I willget back to you after referring this link

  • Manas Ranjan Prusty asked a question in Wine:
    What are the maximum accuracy of the UCI classification datasets using two layered ANN classifier?

    I want to know the maximum accuracy that can be obtained for UCI data sets such as wine, iris, wine quality, abalone, glass identification, balance scale, etc using a two layered MLP using back propagation algorithm. Is there any paper which says this?

    Thanks in advance.

  • Ahmed A. El Tayyan added an answer in Dye-sensitized Solar Cells:
    Why does a sudden dip occurs in dye sensitized solar cell J-V curves?

    I am trying to record J-V curve for a Dye sensitized solar cell. but i m getting a sudden dip at the start of my measurement. after that the curve follows the usual nature of a typical dssc curve. what may be the possible reasons for this

    Ahmed A. El Tayyan · Al-Azhar University - Gaza

    Ive seen somthing like this, i guess the reason is the measuring setup

  • Ana Kleiner added an answer in Micro-Electrical-Mechanical Systems:
    Which is the most accurate location to place an inertial sensor for measuring center of mass displacement?

    (considering that I use triaxial accelerometers) Some papers use L3 or L5 spinal process, but there is a lack of references about that parameter.

    Ana Kleiner · University of Campinas

    Pelvis or center of L5/S1. I support what Alan said, the David Winter book is a very good reference. Also, if you like, take a look at this work:

    GALLI, M. ; KLEINER, A. F. R. ; GAGLIONE, M. ; SALE, P. ; ALBERTINI, G. ; STOCCHI, F. ; DE PANDIS, M. F. . Timed Up and Go test and wearable inertial sensor: a new combining tool to assess change in subject with Parkinson s disease after automated mechanical peripheral stimulation treatment. International Journal of Engineering and Innovative Technology, v. 4, p. 155-163, 2015.

    Good luck with your studies!

    With Kindest Regards,


  • Xinsheng Teh added an answer in MLST:
    How can I compare two incomplete whole genomes to find the SNP calls?

    I have two incomplete whole genome sequencing data belong to Helicobacter pylori strains. They are done by using Illumina Hiseq 2000 platform. Both of the strains are MLST identical, meaning there are derived from the same strains, only that they are phenotypically different. I would like to know the if there is any mutation occurs throughout the experiment, may I know if they is any way to do the whole genome alignment on them? I tried using cluster W and Muscle on MEGA5, apparently the data is too large for it. May I know if there is any other software that allow whole genome alignment? Besides, should I concatenate the contigs together in order prior for the alignment? Your advice is highly appreciated. 

    Xinsheng Teh · University of Malaya

    Hi Shabhonam,

    Thank you for your advice, I am currently using MUMmer to perform sequence alignment on two draft genomes. However, I face some problems in executing the run because each draft genomes are consisted of many contigs (around 20-30 contigs). The system just could not find the alignment:

    attached below is what i have performed:

    nucmer --prefix=UM077_UM119 UM077.fasta UM119.fasta

    show-coords -rcl UM077_UM119.delta > UM077_UM119.coords

    show-aligns UM077_UM119.delta UM077 UM119 > UM077_UM119.aligns

    it showed error as below

    ERROR: Could not find any alignments for UM077 and UM119

    Can you explain in details about fastasplit? Thank you