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  • Herri Mulyono added an answer in SPSS:
    How can I calculate false discovery rate using spss ?

    I am planning to calculate of false discovery rate using spss as comparison to Bonferroni adjustment to the p value. Can anyone show me a step-by step procedure to calculate false discovery rate using spss? 

    Note: I know little about spss syntax

    Herri Mulyono · Universitas Muhammadiyah Prof. Dr. Hamka

    Hi Bruce, thanks for the details and I have made a template file for the spss syntax using your procedure. And again, it is very helpful. 

  • Jetty Ramadevi added an answer in Plant Tissue Culture Techniques:
    How can I get a rooting plant form apple tissue cultures?

    I am using a reference "Jia-Long Yao, et al. (2013) Plant Cell Rep. 32: 703-714".

    I am now observing whether it is rooting or not. Please tell me the good advise what to do. 

    Jetty Ramadevi

    Hi! Check the following links you get useful information.

    A New Method for Rapid In Vitro Propagation of Apple and Pear

    In vitro cloning of apple (Malus dometsica Borkh) employing shoot tip cultures of M9 root stock

    Google it just by typing apple tissue culture you get vast information.

  • Mike Widdowson added an answer in Petrology:
    Will the "basalt" used as a standard for analyzing high Mg rocks cause any analytical errors for the rocks concerned?

    The analysis which I received recently has high MgO wt %. But the standard used during analysis is a basalt. Hence is it compulsory to use high Mg sample as a standard while reanalysing the samples for better accuracy?

    Mike Widdowson · University of Hull

    This depends, to some extent, on the analytical method used. However, whether using ICP or XRF for whole-rock, the equipment should be calibrated using recognized standards. The most commonly and accepted ones for internal calibration (basalt - andesite are the USGS standards - these include BHVO-2, BIR-1, AGV-2. See summary at attached url:




    DTS-2B is a dunite which would extend the Mg calibration, but this one is less commonly used.

    If the equipment is calibrated using these, then the calibration lines should be reliable within the limits of the range of element compositions that these samples exhibit. For instance if the Mg is calibrated with standard samples ranging from 8 - 20% MgO (e.g., basalt to komatiite composition), then any unknown sample lying between these values should lie on the calibration, and thus be an accurate determination. If element concentrations lie beyond the calibration limits (for any element), then the error increases the further the unknown sample concentration lies beyond these 'calibration values'.

    The best option is to request the standard suite list from your analytical lab, and determine whether your samples fit into their 'calibration limits'.

    Good luck.

  • Danielle Schmid added an answer in Parkinson's Disease:
    Any advice on compound heterozygous Parkin or PINK1 gene mutations?

    My colleague and I discussed about the following three patients with early onset of Parkinson's disease. 

    Case 1 carries  p.A340T & p.N521T of PINK1 gene, both of which variants are not pathogenic  according to PDmutDB. Therein, this case does not carry PINK1 gene mutation. 

    Case 2 carries p.A206T & p.V380L of Parkin gene. p.V380L of Parkin gene is not pathogenic, although function of Parkin p.A206T is unknown. So, case 2 is not a compound heterozygous Parkin mutation carrier. 

    Case 3 carries p.S167N & p.R366W of Parkin gene. p.S167N of Parkin gene variant is not pathogenic, although p.R366W is pathogenic according to PDmutDB. Therein, case 3 is not a compound heterozygous Parkin mutation carrier. 

    What would you think? Thanks.


    Danielle Schmid · Case Western Reserve University

    I disagree with all three conclusive statements.  A benign gene mutation is still a mutation--it does not have to pathogenic..  In each case, the patients have two different recessive alleles for the same gene.  Therefore, they are compound heterozygotes by definition.

    However, I have not worked with humans--perhaps these words are used differently in a clinical setting?

  • Saleh Alkarim added an answer in Western Blot:
    Any advice on an SDS-page problem?


    I have trouble with running gel of western blot. I ran my protein with 12% polyacrylamide gel, 30mA for 1h. After I ran, I found bands expanded (see the picture). Can you tell my what happen and what should I do to solve this problem? Thank you very much. 

    Saleh Alkarim · King Abdulaziz University


    i agree with Emmanuele Ambrosi , also , i want ask about the voltage you run your SDS-PAGE
    Find the links here , there are many discussions about this issue will help you

    Good Luck

  • Erwin Groot added an answer in Cognitive Neuroscience:
    I'm looking for the best way to measure attention in elderly. Does anyone have a suggestion?
    Both neuropsychological and neurophysiological biomarkers have my interest.
    Erwin Groot · Albert Schweitzer Ziekenhuis

    Thank you very much Alfredo.

  • Sandip Chakraborty added an answer in Toxocara:
    Which method is appropriate in order to perform DNA extraction of Toxocara eggs?

    Which method is appropriate in order to DNA extraction of Toxocara eggs?

    Sandip Chakraborty · Disease Investigation Laboratory, Dharmanagar, Tripura (N)

    You can please refer to the links provided below for obtaining certain valuable informations:-

    1. http://www.parasitesandvectors.com/content/5/1/288

    2. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3670902/

  • D. V. Grigoriev asked a question in Mosasaurs:
    How to distinguish mosasaurian teeth from crocodilian?

    Mosasaurs have different types of teeth (see attached figure from Bardet et. al, 2014.)

    But so do crocodiles...So, How to distinguish  in general mosasaurian teeth from crocodilian? (for example the first picture shows Crocodyliformes tooth, and the second Prognathodon sp. (Mosasauridae))

  • M. A. Khanday added an answer in Abstract Algebra:
    How do I find the total number of normal subgroups for symmetric group $S_n$ and $A_n$ and is there any relation between the normal subgroups of two?

    How to find the total number of normal subgroups for symmetric group Sand An and is there any relation between the normal subgroups of two?

    M. A. Khanday · University of Kashmir

    The alternating group of degree n is always a normal subgroup, a proper one for n ≥ 2 and nontrivial for n ≥ 3; for n ≥ 3 it is in fact the only non-identity proper normal subgroup of Sn, except when n = 4 where there is one additional such normal subgroup, which is isomorphic to the Klein four group.

  • Upendra Kumar Devisetty added an answer in Gene:
    How I can create Heatmap diagram from a list of genes?

    I am trying funRich platform but the automatic mapped genes reduced my desired number. If I input 1000 genes it only mapped below 100 genes. Is there any soft or online resources have that can easily solve this problems. I am looking for your suggestion. 

    Upendra Kumar Devisetty · Oregon State University

    You can try either heatmap() or heatmap.2() functions in R which have several options 

  • Ehsan Khalili asked a question in Panel Data:
    Which model in panel data I can use for nons-tationary data?

    topic of my research is panel data:

    some variables are related to each other (energy consumption and co2 emission) in  theory but data is non-stationary and we can't reject null hypothesis that says no co-integration.

    what is solve of this problem??

  • Bruno F B Silva added an answer in Microemulsions:
    Does the size of the water nanodroplets change with increasing the water-in-oil microemulsion dilution with oil ?

    i create a stock water-in-oil microemulsion in presence of ANIONIC SURFACTANT with the constant water to surfactant  molar ratio, i want to dilute the explained system with continuous phase (Oil ) ,Does the size of the water nano droplets in the water-in-oil microemulsion varies by the microemulsion dilution with the oil?

    Bruno F B Silva · University of California, Santa Barbara

    I agree with Titus, but only if the dilution is really very low, when the overall concentration of surfactant starts to be comparable with the surfactant cmc in oil. (It is a anionic surfactant, so the cmc should be very low in oil). 

    I would like to raise some concerns about DLS and interpretation of the data. Even at moderate concentrations of water/surfactant micelles in water, the diffusion of such micelles becomes slower because the micelles bump into each other. Therefore, if the data is not properly taken care of, the apparent radius (which is inversely proportional to the diffusion coefficient) will appear larger. With NMR self-diffusion this is very easy to correct having the micelle volume fraction in mind. With DLS it should be similar, but with some tweaks, since collective diffusion coefficient (measured by DLS) is slightly different from the self-diffusion (measured by NMR). I think this might be what you are observing.

    Abbas, what is the range of surfactant+water volume fraction along the dilution line, so we can have an idea of what hypothesis is more likely? and the cmc of the surfactant in oil?

  • Hussein Elasrag added an answer in SMEs:
    Data on European SMEs?

    Does anyone have data (location, size) of European SMEs?

    Hussein Elasrag · Ministry Of Industry And Foreign Trade

    many thanks for this  useful links, i think Dr. Loukas Tsironis can find all he need in it

  • E. Litovsky added an answer in Thermal Analysis:
    What is Hydro-NM-Oxide and why does it have such low thermal conductivity? I ask this question in the quest to study the thermal insulation property of nanocoatings in energy efficient buildings.
    Very low thermal conductivity in the order of 0.017 W/m.C.
    E. Litovsky · Integrity Testing Laboratory Inc.

    1.       E.Ya. Litovsky, M. Shapiro. Gas Pressure and Temperature Dependences of Thermal   Conductivity Porous Ceramic Materials. Part  I. Refractories and Ceramics with porosity below  30%,  J. American Ceram Soc. 75 [12], pp. 3425-3439, (1992).

    2.      Litovsky E., M. Shapiro, A. Shavit, “Gas pressure and temperature dependences of thermal conductivity porous ceramic materials. Part II. Refractories and ceramics with porosity above  30%”,  J. American Ceram. Soc., 79/5, 1996 1366-1376.

    3.      Litovsky E., T. Gambaryan-Roisman, M. Shapiro, A. Shavit, “Effect of Grain Thermal Expansion Mismatch on Thermal Conductivity of Porous Ceramics”,  J. American Ceram. Soc. , vol 82, No 4, pp 994-1000, 1999.

    4.      Litovsky E., Gambaryan-Roisman T., Shapiro M. and Shavit A, Heat Transfer Mechanisms Governing Thermal Conductivity of Porous Materials, Trends in Heat, Mass & Momentum Transfer, Research Trends, Invited, Vol. 3, pp 147-167, 1997.

    5.      Litovsky E., Gambaryan-Roisman T., Shapiro M., Shavit A., “Novel heat transfer mechanisms in   porous ceramic materials”, High Temperatures-High Pressures, 1(33): 2001, pp. 27-34.

  • Jules Lloyd Hammond added an answer in Comsol Multiphysics:
    How can I mesh a 3D geometry that includes serpentine channels in COMSOL?

    Hi every body,
    I have an issue with meshing my geometry and I do not how to fix it, 3 cubic blocks putted each on the other and they have different heights with the same contact area, the top and bottom surfaces of the first and last blocks include channels, serpentine ones. I am still getting weird results from solving the problem and once I stop running it I got a lot of error messeges related to the mesh at either domains,  surfaces  or points, specific x y z dimension points.
    Any idea or help of how to mesh like this kind of geometries will be really appreciated!
    Thanks in advance.

    Jules Lloyd Hammond · University of Bath

    Hello Mohammed,

    Are you able to upload your geometry so that we can examine? Maybe there is an issue we can assist with.

    In addition to the great link Harikrishnan provided, below are links to a video and blog entry that may be of help:




    Kindest regards,


  • Bishwo Pokharel added an answer in Cattle:
    What are the new approaches of animal nutrition sector?

    This question is with regards to cow and sheep nutrition.

    Bishwo Pokharel · University of Guelph

    studies regarding impact on environment and how that can be tackled by the dietary strategies For eg: Phosphorus and water pollution, methane emission, nitrogen excretion 

  • Adeyemi S. Adeleye added an answer in Nanotoxicity:
    Does anyone know about quantifying graphene/oxide in cells/tissues?

    Does anyone know of reliable label-free techniques for quantifying graphene and/or graphene oxide inside cells and tissues of organisms such as algae, worm, etc.?

    Adeyemi S. Adeleye · University of California, Santa Barbara

    Tian, can you send me a link to the paper/study where you used absorbance so I can read the full protocol? Thank you!

  • Yazan Maswadeh added an answer in Fullprof:
    How can I do rietveld for synchrotron xrd?

    I want to do fullprof rietveld for synchrotron xrd but i have some doubt regarding wavelength lambda1 and lambda2 , I2/I1....Please suggest me regarding my problem .

    Yazan Maswadeh · Central Michigan University

    you can get the lambda1 from the beam configuration in the synchrotron experiment setup , and there is no lambda2 in this case since it is monochromatic beam .. so it would be zero, if your software did not accept zero just put it like lambda1

  • Debika Ch asked a question in Nucleation:
    Does the nucleation rate relate to the particle size and shape?? and if yes then how it is related??

    i want to understand the basics of the nucleation and its relation to the particle size.

  • Sandip Chakraborty added an answer in Bacteriophage:
    Anyone works on Bacteriophage from P. multocida

    I want to ask some questions, any infomation  it will be great

    thanky you

    Sandip Chakraborty · Disease Investigation Laboratory, Dharmanagar, Tripura (N)

    You can please refer to the links below to obtain certain valuable informations:-

    1. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1472319/

    2. http://www.ncbi.nlm.nih.gov/pubmed/14651626

  • R. Daniel Gietz added an answer in Freezing:
    Does anyone use re-boiled Salmon Sperm DNA for Yeast LiAc transformation and get a low efficiency?

    I use Lithium acetate transformation method for transforming intact circular plasmid into yeast.

    In past, I always aliquot a new salmon sperm DNA from commercial tube, then boil in water for 10 min, and put on ice until use for transform, and get a lot of transformants. (and never used re-bolied salmon sperm DNA)

    But for these two time that I get very little of transformants, I use a re-bolied sheared salmon sperm DNA that have a lot of "freez - thraw - boiled" cycle for many time because I aliquot so much and cannot use all. Thus, I kept the boiled DNA in freezer, when I want to use I will boil it agian and agian like a cycle of freez - boli

    Then, my assumption is the salmon sperm that have many time of freez - thraw - boiled cycle will give a low transformants efficiency?

    Does any one face the case like me? or any suggest, please provide

    R. Daniel Gietz · University of Manitoba

    Hi there.. We have found that you can reboil carrier DNA but it does reduce the transformation efficiency in a negative fashion...  Reboiling your carrier DNA can have a dramatic effect on Transformation efficiency so I only worry about it when i am doing a screen that requires 10e6 transformants.  Other times the reboiling effect is minimal... I believe it has to do with the state of your carrier DNA (fragment size)  Years ago we found the larger carrier DNA works better for transformation than smaller sized carrier.  As the size of your carrier DNA decreases so does your transformation efficiency and yield.  This may explain the reboiling effect.  As the size of the carrier is reduced by what ever treatment the transformation efficiency and yield are reduced.

  • Richard Christison added an answer in TA Cloning:
    What has my TA Cloning failed (Insta Cloning kit)?

    1) I want to clone 700 bp RAPD fragment,

    2) final extension for pcr was 30 min to add A overhang

    2) I have gel eluted using quaigen kit and eluted in water

    3) Cloned using Insta TA Cloning kit thermos scientific

    4) Cloning reaction incubated 22 0c for 1 hr and then incubated overnight at 4 oc

    5) insert to vector ration was used as 1: 3 (vector: insert)

    6) ligate was stored at -20 0c for 2 days and then transformed in dh10 cells using transform aid bacterial kit thermos

    7) but 970 bp control fragment provided with kit was successfully cloned no issue with it but fragment which I have eluted that creates problem in cloning

    I got colonies on ampicillin (50ugm/ml) and streptomycin (50) but all showed absence of insert after colony and plasmid pcr. all seems to be false positive

    please see attached photo of plate

    Richard Christison · Freelance Protein Expression Scientist

    Hi Vishal,

    there's nothing obviously wrong with what you have done.

    I'm assuming you are using taq or another polymerase without proofreading for the PCR to leave the extra A. The most likely problem is that you are not getting ligation into the vector for some reason. Did you see a difference between plus and minus insert colony numbers? Try some different ratios 1:1 to 1:10. Try a different PCR product as a control, in case it is sequence related. 

    Otherwise have you checked the cloning by restriction digest? Your PCR might not be working for some reason.


  • Joan Vaccaro added an answer in Autistic Children:
    Does Nutritional Intervention have any benefit for Autistic children?

    what would be the ideal age for nutritional intervention to start ffor autistic children?

    Joan Vaccaro · Florida International University

    I am glad to be of help, Krishna. Please let us know if you need any other information.

  • Pierre-Louis Cyr added an answer in Formalin Testing:
    Which level of formalin can a human consume?

    Formalin is a ferocious name and in third world country like Bangladesh, in every food is formalin contaminated to keep free from microorganisms. Though it is a harmful agent but our digestive system can digest a certain level. I want to know the exact level, can you help me with reference?  

    Pierre-Louis Cyr · Laval University

    Formaldehyde smell can be detected at very low concentrations (about 2 ppm). In America, 20 ppm is considered as immediatly dangerous for life and health. OSHA TWA is 0.75 ppm (with a 2ppm ceiling). Tests on rats suggest a greater toxicity when inhaled with LC50 of 250-480 ppm (4 hours). LD50 of formalin is about 800mg/kg. Normal formaldehyde concentration in human blood is 2.61 +\- 0.14 ug/kg. Formaldehyde uptake is not recommanded but the chemical is rapidly metabolized to formic acid and then to CO2 (or incorporated to cellular molécules). Hope it helps and good luck in finding nutritional related info !

  • Pamela Labra added an answer in Didactics:
    What are 21st century skills related to technological, didactic and methodological resources of blended learning on the delivery of education?

    We are informed that for teachers/instructors to remain informed they should take advantages of newly evolved 21st century skills. Are any well resourceful research on these potential skills!?

    Pamela Labra · University of La Serena

    This link could be useful for you. It presents the skills to be developed/acquired by future teachers in teacher formation processes in my country.


  • Patrick Guest asked a question in Protein Purification:
    Is a start codon in the MCS a problem for protein purification?


    I am attempting to purify a protein of interest and having sequenced the expression plasmid, I noticed an additional start codon which appears to form part of the MCS and sits upstream of my protein of interest, but downstream of the TEV cleavage site. Would this potentially mean I may purify a version of my protein of interest with an additional N-terminal 11residues?

    If so would it be worthwhile carrying out an SDM experiment to remove this start codon?

    Any advice would be greatly appreciated.


  • Xavier Le Polozec added an answer in Millimeter Waves:
    With the ever-increasing spectrum crunch and demand for it with each passing day, is it feasible to use millimeter waves for newer applications?

    Is it feasible and advisable to use higher frequencies to solve the severe spectrum crunch, ignored till now? It mean moving towards higher microwave frequency bands towards millimetre waves (above 30 GHz). What are the other options available?

    Xavier Le Polozec · Ericsson

    Hi Pankaj

    I found a very interesting white paper on 5G


    ......The need to evaluate possible candidate bands in higher frequencies to address new spectrum beyond the year 2020 for ultra-dense networks. Such frequencies are needed to allow very wide bandwidth channels to support very high data rates and short-range mobile connectivity (e.g. 500 - 1000 MHz of contiguous spectrum per network to support the multitude of services described in section 3.2.1) Total spectrum requirements should take into account the potential need to accommodate multiple networks Therefore it is proposed to study technical feasibility of the ranges between 6 GHz and around 100 GHz, in particular those where primary or co-primary allocation to mobile in the ITU Radio Regulations exists already. The lower limit for the band range (above 6 GHz) should be further assessed.....

    • http://www.ngmn.org/uploads/media/NGMN_5G_White_Paper_V1_0.pdf

    Best Regards

  • Kanad Mandke added an answer in P300:
    Has anyone come across P300 for multiple deviants?

    I have cum across loads of published research on MMN evoked by multiple deviants... Its just intruding to know if the same is applicable for P300?

    Kanad Mandke · University of Nottingham

    As suggested by Pragati, P300 is indeed seen in complex stimulus setups as well. Even if you have an anticipatory motor response or not. Salisbury et al (2001) have argued that motor responses do have an effect on P3 response amplitude. 

    There are plenty of studies showing P3 responses to tri-tone stimulus setups, for instance, S1 is standard, S2 is a distractor and S3 is the target. This can be viewed from the perspective of relevance detection. Omitted P3 is common too. A good starting point is Polich (2007). 



  • Kamel Chettab added an answer in Gene Transcription:
    Is there any alternative tool to pathway studio analysis?

    I has been disturbing by the question that how to combine a large list of genes with transcript abundance and relevant metabolite contents (24) in integrated pathways? IPA and pathway studio may be the good choices, but not free. Is there any alternative tool to these two tools?

    Kamel Chettab · Claude Bernard University Lyon 1

    two software that to analyze your transcription profiles

    - http://www.reactome.org/PathwayBrowser/

    - https://david.ncifcrf.gov/ 

  • Cheo Emmanuel Suh asked a question in Metallurgy:
    What is the best current chemical metallurgy technique of beneficiation for magnetite ore?

    I am working on the beneficiation of magnetite ore and possible metallurgical testworks to reduce the levels of Si, P in the ore. Any new ideas from chemical metallurgy that can help us advance with this project? Grind size alone does not seem to solve the problem