Q&A

ResearchGate Q&A lets scientists and researchers exchange questions and answers relating to their research expertise, including areas such as techniques and methodologies.

Browse by research topic to find out what others in your field are discussing.

Browse Topics

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
  • Paul Ouma added an answer in Netlogo:
    How can I calculate local moran's I in Netlogo?

    I am interested in computing local moran's I in Netlogo to identify significant clustering. While I am able to export my data into another software to compute this, there is no software I am aware of to compute moran's I that will take into account the world wrapping. 

    Paul Ouma · KEMRI-Wellcome Trust Research Programme-Pwani University PGD program

    the same issue has been addressed in https://groups.yahoo.com/neo/groups/netlogo-users/conversations/topics/3047

  • How do I find single copy gene using bioinformatics approach?

    I want to find out  the single copy gene from a particular genome whose genome has been sequenced. so, can anybody help me anything  related to this.

    Haiwei Luo · The Chinese University of Hong Kong

    You can first cluster the genes into orthologous gene families using OrthoMCL, and then write a script to identify single-copy genes.

  • Khaled F M Salem added an answer in Growth Medium:
    Does anyone have experience in growing wheat in sterile conditions?

    I need to grow wheat (chinese spring) plants in plates for about 2-3 weeks.

    I would like to know the seed sterilization + the growth medium protocol and the plates size.

    Thanx

    Khaled F M Salem · Minoufiya University

    Dear Dr Maria,

    Greetings, I would like to thank you for your question. It seems from your question, you ask about wheat growth under in vitro condition. If so, the best explant used is embryo especially immature better than mature after 10 -14 days (2-4 mm) under microscope you could get the embryo. The best media is MS media with some modified.

    with best regards

    Khaled

  • Hossein Soleimani asked a question in Reactor Design:
    Müller-Rochow Process reactor design for organosilicones?

    I need technical details for design this fluized bed reactor and over view of total materials and catalists

  • How Stacking fault energy is a function of material?

    Cu and Al have same FCC crystal structure but differ in SFE (stacking fault energy). Why is this so? On what parameters SFE is dependent and how it is calculated?

    Tapan Chatterji · Institut Laue-Langevin

    There exist ab-initio calculations of the stacking fault energies of the fcc elements. Read for example:

    Rosengaard and Sriver, PRB 47, 12865 (1993)

    Wu et al., Appl. Surface Science 256, 6345 (2010).

  • Safwan Paramban added an answer in Rainfall:
    I have done the interpolation using Rainfall data.In the output properties cell size 30 meter,But when we are measuring the pixel it showing 390 mtr?

    Using rainfall data i have done the IDW Interpolation its cell size showing  a x, y = 0.0039291792, 0.0039291792. degree.

    To get the cell size 30  meter  have projected the  output raster.Its properties it showing 30 meter correctly.

    But when we measure the cell size using measure too in arc gis it showing 390 meter.

    I want it in 30 meter.

    Can any body help me to do this please.

    Safwan Paramban · United Arab Emirates University

    Thank you for your valuable suggestions.

    I have done it through the Environment setting of IDW Interpolation techniques.

    Thanks

  • Saba Niaz added an answer in GaussView:
    I calculated negative frequencies for UV-Vis spectroscopy of a ruthenium complex, what did I do wrong?

    Hi all,

    I am running a frequency calculation on one of the ruthenium complexes to find a minimum and I ended up with three imaginary frequencies:
    -85.3956 -67.4478 -21.9335

    I have tried:
    1- change the cartesian to to z-matrix and optimize it, yet, it gave 3 frequencies with slightly less value than before.
    2- visualize it with gaussview change the conformation and it gave the same result as 1. NOT: the direction of the imaginary frequencies is in the Z axis which breaks the symmetry from Cs to C1.
    3- when i tried opt=tight,calcall, Gaussian broke the symmetry but it end without imaginary frequency.
    my question: since this is saddle point is it Ok to continue calculating the spectra (uv_vis) and emission regardless of the values of imaginary frequencies?

    thanks

    Saba Niaz · University of Kashmir

    dear sanaa,

    send me the optimised file and i will try to look into ur molecules problem . send me the output file of ur complex if u r using gausian as the software u can also send the file as an direct message in my research gate account . (if its ok with u)

    plus try changing the basis set . as i have myself observed the problem of attaining imaginery frequency . trust me dont work on this molecule as u will end up in getting incorrect results . 

  • Any suggestions on PCR sequencing of two closely running fragments?

    Dear community,

    we would like to sequence a PCR product. Unfortunately, we have two differential allelic products running on agarose gel very close together. Has somebody any  idea, to better separate these for further processing?

    Many thanks in advance :-)

    Thorsten

    Laura Crisponi · National Research Council

    you can clone the PCR product and then sequence the positive clones. In this way you will discriminate the two allelic products

  • Yuan-Yeu Yau added an answer in Transgenic Mice:
    Is there a complete list of candidate locus for site-specifit integration transgenic mouse construction?

    I'm currently preparing to construct transgenic mice with site-specific integration method, so that I can get a single-copy mice with life-long expression of my system in all kinds of tissues. I wonder how many candidate locus is there? Since I have a complex system with several component, I would need 3 such locus, so is there a complete list? Any literature? Thank you so much!

    Yuan-Yeu Yau · Northeastern State University

    I think Rosa26 locus is one of them for mouse transgenesis. See link below: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3333879/

  • How to improve reverse transcription yield?

    Hi, there. I need to start experiment from very few amount of total RNA. Is there any way to improve the cDNA yield? Will it work if I extend the incubation time at 48℃ from 30 min to 1 h? 

    Thanks in advance.

    Saeid Abu-Romman · Al-Balqa' Applied University

    Dear Zheng Wang, I have used several kits for RT-PCR and found that the best (high yield) were INTRON (Korea) and KAPA.

    Good luck

  • Is there any minimum number for studies that should be included in meta-analysis?

    I do a meta-analysis under very specific criteria, however, I can’t find more than nine studies that fit my criteria, is that number acceptable and if not how many studies should I have?

    Indeed, the topic of this meta-analysis seems new, as I can’t find another meta-analysis within same criteria.

    Thank you.

    Ma'en Zaid Abu-Qamar · Edith Cowan University

    It should fine with nine studies as you will be examining the best available evidence concerning a specific issue

    All the best

    Ma'en

  • Haiwei Luo added an answer in PacBio:
    Does anyone have an expertise closing a microbial genome with the combination of PacBio and HiSeq data?

    We are looking for currently available script/software.

    Haiwei Luo · The Chinese University of Hong Kong

    You may consider using SPAdes.

  • How to calculate the electron affinity (EA) of the atoms that form anions in case of Ce activated Ca2SiO4?

    How to calculate the electron affinity (EA) of the atoms that form anions in case of Ce activated Ca2SiO4? Also, what will be the ionic radii of Ca with respect to this host?

    Dr Rujuta Barve · Indira Gandhi Centre for Atomic Research

    Please find attached the details as requested by you.

    best wishes,

    Rujuta

  • Can anyone suggest me for capital cities traffic models review publications ?

    Currently, I am working about traffic model in Bangkok, Thailand. I would like to review different models and their policy in other countries. Please kindly give me a url or publications. 

  • Marko Josipović added an answer in Microorganisms:
    Does drip fertigation affect soil fertility and would it affect the groundwater table?

    In drip fertigation we apply once in 4-7 days. mostly all water soluble fertilizer are acid forming one. so by applying continuously there is a chance of decreasing microbial load in soil which in turn affect soil fertility. more over microbes are seen in every soil but in drip we concentrate only to crop alone then were microbes get food.

    we do not distribute soil in drip field so weather soil get hard and when it rains water infiltration will be low so ground water storage will be also less

    Marko Josipović · Poljoprivredni institut Osijek

    Dear Mr. Jeevan,

    As many here coment, it is necessary be careful with quantity of applied water and nutrients.

    1. Optimum quantity of water could not grow up the water table.  

    2. Some fertilizer coud increase pH value, so it would be necessary measuring and investigate on direct site in your case. O course as Prof. Barlow wtrite, "the management of the irrigation & fertigation" are very important.

    3. Microbal activity with good managemet of the irrigation and fertigation are right and in that case the chanse for big disturbance are small. But, it would be good if you might investigate that for your safety.

  • Is there any formula as equation of state for water?

    I am trying to simulate water-vapor as multiphase flow at room temperature using lattice Boltzmann method. In the selected method, we use an EoS to simulate multiphase flow. So, the flow follows the EoS in the simulation. All of the available EoSs (such as RK, vdW, C-S, P-R, ...) have been defined gases, so usually the density ratio at room temperature is overestimated. I want to know if there is any formula which defines density-temperature relation for a real substance (except gases) such as water, oil or ....

    thanks

    Abdolrahman Dadvand · Urmia University of Technology

    the "Tait" Equation.

  • Why is the open circuit voltage of lithium ion battery high?

    I have assembled Li ion batteries with Li1.2Ni0.3Co0.3Mn0.3O2 as cathode material. Why the open circuit voltage of the batteries is high (2-2.5 V)? 

    Arun Nagasubramanian · TUM CREATE

    It would be helpful If you can provide details of the chemistry. what is the counter electrode you employed? Is it a half cell versus lithium counter electrode or a full cell against some anode (like graphite/LTO etc.)? usually half cells versus lithium would give an OCV around 3V. Full cells versus graphite can typically show around 0V.

  • Is there a tool to display phylogenetic tree alongside with its aligned sequences?

    I would like to display aligned sequences along with the phylogenetic tree, with each taxa name matching a sequence in an aligned form. Anyone knows a tool to do this? Thanks.

    Haiwei Luo · The Chinese University of Hong Kong

    You can use Figtree.

  • Bibhash Chandra Verma added an answer in Soil:
    Soil carbon is influenced by which factors in coal mine regions?

    Around coal mining regions,where there is a possibility of coal particles or carbonate or some other contamination of soil, Can all these affect organic or inorganic carbon of the soil?

    Is these contamination hindered with soil carbon analysis? 

    Bibhash Chandra Verma · Indian Council of Agricultural Research

    soil carbon analysis is not meant for one fraction. There are several fraction of soil carbon like total, organic, inorganic, non-labile, labile, microbial and so on. now coal particle itself a carbon rich compound. Hence, it may affect the soil carbon analysis. beside this, the purpose of analysis governs, what fraction you want to know. every fraction will respond differently, which depends on the so many factors like soil, environment, climate, crop biomass etc.

  • Akash Singh Chauhan added an answer in HFSS:
    How can i calculate phase velocity vs frequency in eigen mode(master/slave) boundary in hfss?

    i am simulating a helical slow wave structure of a twt in hfss software so how can i obtain phase velocity vs frequency?   i am  working in eigen mode of hfss ?

    Akash Singh Chauhan · VIT University

    Hello Sir,

    I think this link will help you.

    http://www.emtalk.com/tut_2.htm

    You can also find HFSS tutorials regarding this diagram.

    Regards

  • Interested in performing studies on local e-government development in your country?

    In the past years I have been involved in studying local e-government development in Portugal through the observation of municipalities' websites. I am also interested in performing international comparative studies. For that it would be necessary to collect data in other countries using the same methodology.Do you know who might be interested?

    Anna Sołtysik-Piorunkiewicz · University of Economics in Katowice

    I am interested very much.

    Please tell me more about the methodology

  • Saeid Abu-Romman added an answer in Auxin:
    What is the possible mechanism to inhibit lateral shoot or bud development?

    What is the auxin concentration need to maintain the inhibition of the lateral shoot and how the auxin will help in that process. at the same time auxin is produced more at shoot apex and young leaves , but how it will help in root initation.  

    Saeid Abu-Romman · Al-Balqa' Applied University

    Dear Moola, I would suggest to try different concentration of auxins to determine the best level, since the optimal concentration is species- and growth sage-dependent.

    Good luck.

  • Aamir Javed asked a question in ICSI:
    What is the reason for the single ProNucleus (PN) some time after ICSI?

    How The Single PN or The Overlapped PN Can be Differentiated , What Is The Reason Behind The Single PN Development ?

  • Emmanuelle Cugy added an answer in Hypoxia:
    How can I assess level of consciousness during exercise?

    I am looking for a method or test to assess level of consciousness during exercise in hypoxia. Do you have any suggestions for this?

    Emmanuelle Cugy · Centre Hospitalier D'Arcachon

    You can probably found some method in these articles. Some are about exercise in hypoxia, some about consciousness and anesthesia.

    In one, determination of the "time of useful consciousness" (TUC) was inability to add two-digit numbers correctly. It would be the best and easier method for you, because others methods need some devices.

  • Shantanu Saha added an answer in Thin Films:
    Does anyone have knowledge on the composition of ZnMgO?

    I have used a target of Zn0.85Mg0.15O  to produce a thin film of ZnMgO on Si substrate followed by phosphorus implantation by plasma immersion ion implantation and annealing at 700, 800, 900 and 10000 C. How could I measure/calculate the composition of ZnMgO thin film now? Is it possible that the composition of the material which is already fixed could be changed after this processing? If yes then how could I ensure it?

    Shantanu Saha · Indian Institute of Technology Bombay

    Sreenivas Sir, Thank you very much. I think this is the easiest way to determine the composition.

  • Rodi Abdalkader added an answer in Thin Layers:
    I have made liposome with hydration thin layer method and t's shown multivesicular vesicle, why it could be happen?

    after hydration method, next i reduce the size using extrusion method, i checked the morphology using TEM it's shown multivesicular vesicle, why it could be happen?

    Rodi Abdalkader · Kyoto University

    Whtat phospholipid composition do you use ? And at what temperature you conduct hydration? 

    After hydration you could sonicate liposomes from around 10 minutes and then extruded through 100-200 mm filter. You must have SUV  liposomes. Another thing is after hydration it was suggested that around 5-10 cycles of freezing and thawing of the liposomes could improve and shrink the space between the phospholipid layers. 

  • What are the main causes of retention time instability in reversed-phase analysis by HPLC?

    In analysis of a weak acid with pKa of 4.6, using mobile phase of phosphate buffer pH 7.7 and methanol (63:37, v/v) and hypersil C18 column, the retention time of this analyte is not stable (it is decreasing with time), although different types and composition of buffer and different pH were tested, but the problem was the instability of the retention time (decrease in retention time).

    Abdullah M Alhamdi · Sultan Qaboos University

    1- decrease in temp. or increase in temp. will change the retention time.

    2- change in mobile phase pH can cause large changes in retention time.

    3- the mobile phase should be prepared once

    4- look for air bubbles in the system

  • Kanticha Korsesthakarn added an answer in Papers:
    Where can I download ISI papers?

    download ISI papers

    Kanticha Korsesthakarn · Chulalongkorn University

    You can use your institution VPN to download them (If your institution buy licenses)

  • Fuat Güzel added an answer in Activated Carbon:
    How to interpret the external surface area of an activated carbon which is greater than the BET surface?

    I prepared a activated carbon with high external surface (2030m2 / g) compared to the BET surface (1230m2 / g)?

    How can I interpret this?
    where: BET surface area = Langmuir surface+ external surface ?

    Fuat Güzel · Dicle University

    It isn't possible. The external surface area is equal to the mesopore surface area. Bet surface area corresponds to sum of the micro- and mesopore surface area. Therefore, it becomes always smaller than BET surface area.

  • Harald G. Dill added an answer in Dolomite:
    Is this early dolomitization?

    This thin section is stained by alizarin red, the calcite is probably a late stage pore filling, but why the unstained dolomite prior to the calcite? what a process would be prefered? Thanks!

    Harald G. Dill · Leibniz Universität Hannover

    Dear colleagues,

    I would like to reiterate my question for more information; to get a more precise picture we need to know the entire section (litholog) or at least an insight into the footwall and hanging wall rocks of the rock slap. The risk of  drifting away in speculations is rather high, even if  I consider all answers as being benevolent and very well meant.

    Don´t take it amiss.

    Best regards
    H.G. Dill