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  • Zoltan Podor added an answer in Standard Error:
    Should I consider only variables with significant values in the summary of model.avg {MuMIn}?

    the summary() of a model.avg made with MuMIn in R, give a lot of interesting results, in particular model averaged coefficients (estimate, standard error, adjusted standard error and a z value with a relative P value). My question is, which kind of test has been done to obtain this P value and in particular what is the relation between the variables turning out to be significant from this test and the relative variable importance obtained from the model average?

    Zoltan Podor · University of West Hungary, Sopron

    Dear Tiago!

    Let us denote mm the model, you can get the parameters:


    Or try mm[1], mm[2], nad so on

    Best wishes: Zoli

  • I. Bremnavas added an answer in Image Security:
    Is any paper published under the two topic Image security using chaos in cloud environment?

    I have needed the information about chaos based image security in cloud environment.

    I. Bremnavas · Jazan University

    Hai Guys, I need a paper related mobile health care security. Is it possible anyone to help me.

  • What is the protocol for determination of growth of candida albicans by flow cytometry?

    I am working on some of the liquid media, which are used to grow C. albicans. Now I wish to find out the pattern of growth, of C. albicans on these media, with the help of flow cytometry. Can anyone suggest the links or research papers in this regard?

    Anubhav Singh Nahar · Institute of Microbial Technology


    firstly do check that whatever media you are using in that candida is forming filament or  not. if it is forming filament than none of technique can help you. if it is in yeast form you can also check the growth pattern with 600 nm uv in  96 well plate reader. 

  • Morgane A. L. Comby asked a question in Indicators:
    How to compute individual values of Chao1 index for individual samples using EstimateS ?

    Using EstimateS (9.1.0) i computed "Diversity Stats" (Diversity Settings > Estimators and Indices > Chao1 and Chao2 bias correction > Use bias corrected formula for Chao1 and Chao2 indices) in order to get the values of Chao1 indices of my samples. But doing that i only get cumulative values of Chao1 indices (with Chao1 indices increasing with the number of samples considered). Does anyone know how to get the independant values of Chao1 index for each of my sample? (well i can do it by hands... but i am sure it might be possible somehow using EstimateS...?).
    Thanks for your help

  • Is there a version of Rado theorem for \rho-harmonic ?

    I outline  a result of this type. Let $h:D\subset M \rightarrow N$ be $\rho$-har on an domain $D$
    of $M$. If $J_h \geq 0$ and $J_h$ is not identically zero in $D$,
    then the zero of $J_h$ are isolated.

    We now state   a generalization of G.
    Alessandrini, V. Nesi theorem.

    Suppose that $ds= \rho |dz|$ is metric on domain $G\subset
    \mathbb{C}$, $\rho \in C^1(G)$, $K_\rho <0$, $S= (G,\rho |dz|)$,
    and $h:\overline{\mathbb{U}}\rightarrow G$ is continuous. Define
    \, $\Gamma(t) = h(e^{it})$.
    Suppose the above notation and
    \item $h$ is univalent on $\mathbb{T}$ and $D= Int (\Gamma)$
    %and , and $h:U\rightarrow D$

    \item $h \in C^1(\overline{\mathbb{U}})$
    \item $h$ is $\rho$-harmonic on $\mathbb{U}$ and $\overline{D}\subset G$
    \item $|p| > |q|$ on $\mathbb{T}$, where $p=f_z$ and $q=f_{\bar{z}}$
    %If $\Gamma$ is a closed Jordan curve ,
    \item $h$ is univalent on $\mathbb{U}$ and $h(\mathbb{U})=D$.

    Miodrag Mateljević · University of Belgrade

    Theorem 5.1.1 in Jost book contains a curvature hypothesis. Several years ago I outline the proof of the following result.
    Suppose that $ds= \rho |dz|$ is metric on domain $G\subset
    \mathbb{C}$, $\rho \in C^1(G)$, $K_\rho <0$, $S= (G,\rho |dz|)$,
    and $h:\overline{\mathbb{U}}\rightarrow G$ is continuous. Define
    \, $\Gamma(t) = h(e^{it})$.
    Suppose the above notation and
    \item $h$ is univalent on $\mathbb{T}$ and $D= Int (\Gamma)$
    %and , and $h:U\rightarrow D$
    \item $h \in C^1(\overline{\mathbb{U}})$
    \item $h$ is $\rho$-harmonic on $\mathbb{B}$ and $\overline{D}\subset G$
    \item $|p| > |q|$ on $\mathbb{T}$, where $p=f_z$ and $q=f_{\bar{z}}$
    %If $\Gamma$ is a closed Jordan curve ,
    \item $h$ is univalent on $\mathbb{B}$ and $h(\mathbb{B})=D$.

  • Atul Prakash added an answer in Soil Science:
    What is the best digestion of a soil sample to determine As by HG-AAS or GF-AAS?
    I have used some methods, but I have losses of Arsenic, I digested the sample in a hot plate.
    Atul Prakash · Mathura University

    For Soil samples

    HCl and HNO3 at 3:1 or 4:1 ratio

  • Does anyone know of a published paper about the impact of information systems on creativity?

    Does anyone know of a published paper about the impact of information systems on creativity?

  • Takvor Soukissian added an answer in Wind speed:
    How can I compute corresponding wind speeds for a location between four different grid points?

    I have the wind speeds hindcasted at four different grid points. But, I want to focus on a location between these grid points. This location has different distances with these grid points. How can I tranfer to this location wind speeds hindcasted at four grid points? Could anyone please advice to me a way for this?

    Thanks in advance for all contributions.


    Takvor Soukissian · Hellenic Centre for Marine Research

    Use directional statistics. For the basic equations see my paper "Probabilistic modeling of directional and linear characteristics of wind and sea states”. I think that the mean direction will be the most representative for your case. Weighted distance interpolation does not work in your case with directions.

  • Heiko Müller added an answer in Visual Impairment:
    How can I create interactive and responsive kiosk/vending machines for blind/visually impaired users?

    In my research I wish to create a voice based interaction system which can be embedded in a public Kiosk for the blind users to communicate. As a result they can start using the kiosk independently. My invention will be software tool which can be embedded in the kiosk that can take the voice of the user as an input and process it accurately to produce best results. The user can use their headphones to listen and they can communicate with the microphone to the Kiosk. This will be an additional device that visually impaired user needs to carry with them to communicate with the Kiosk.

  • Perantho Evan Dias asked a question in Color:
    Could anyone plz provide me with satisfactory reply to my query regarding total phenolic content estimation and detection of phenols in plants??

    Could anyone tell me which is the most accurate test for detection of phenols in plant extract and the best assay for estimation of total phenolic content in the same??? I have used the Fe(III) chloride test for detection of phenols. my control wiz phloroglucinol gives me the purple colour ...however my test extracts are prepared in methanol and also in 0.85% NaCl...but neither give me a purple nor red nor bluish colour which is an indicator of phenols......it gives a yellowish green colour.... secondly on using the FC reagent for estimation of phenols i ve managed to get results.... so im confused weather if my FeCl3 detection test is wrong or the Test for total phenolic using FC reagent is faulty(viz the standard protocol followed for estimation of total phenolics)....... Plz enlinghten me with your valuable inputs

  • Jérôme Juilleret added an answer in Limestone:
    Can any one helps in identification of calcareous plant roots and stems in Quaternary fresh water limestone environment?

    Calcareous plant roots, stems and debris were found within Quaternary fresh water limestone environment. Identification of these plants may reveal their environmental and climatic significance.

    Jérôme Juilleret · Luxembourg Institute of Science and Technology


    I think that only base on the morphology of the rhizolith, or tuffa it is impossible.

    You need to find some seeds, or real organic material.

  • Fabrice Clerot added an answer in Natural Logarithm:
    Why Log or natural logarithm of Data series require for analysis?

    we consider natural logarithm or lag of the data series for our analysis. But what is the reason behind this. Why we are not considering the raw data for analysis. Is their any paper regarding this. Please answer.

    Fabrice Clerot · Orange Labs


    this paper does a good job at gathering the many reasons why log transformation can be useful :



  • Paul Dias added an answer in Arterial Stiffness:
    What are the reasons for the non-linear progression between arterial stiffness and thickness?

    Hi, everyone, the paper below reported that the IMT of common carotid artery had a poor correlation with pressure-strain elastic modulus at lower thickness value (CIMT<0.88mm, r=0.24, p=0.08), but this association became stronger with increasing thickness (CIMT>0.88mm, r=0.62, p<0.001) .

    I want to know the physiological mechanism behind this phenomenon. Could you please recommend some papers about this field to me ?

    Thank you very much!

    Paul Dias · Unilever

    Yes it is rightly mentioned. Stiffness (ability to dilate) decreases with increased thickness of  blood vessels (IMT). But there is non linear corellation between thickness and stiffness as there are many mechansim that contribute towards vessel stiffness. and one mechanism contributing is IMT.

  • Rajat Chopra asked a question in QGIS:
    Can QGIS 2.8 be used for watershed Analysis ?

    I wanted to do watershed analysis from DEM, basically calculating the source and sink, catchment areas and Various other analysis which are done while calculating Watershed, Can anyone please help on that

  • What solvents should I use for particle size analysis ?

    i want to do particle size analysis for my high entropy alloy ball milled powder. can any one suggest me the solvent for the same.

    Titus Sobisch · LUM GmbH

    if you are interested in the powder characteristics, you should do the measurement dry. If you want to have information on size distribution for liquid dispersions of the powder, use just these liquid dispersions. Having or not having agglomerates under these conditions then is part of the story you should be interested in.

  • How can I purify target protein from SF9 insect cells transfected with baculovirus?

    I want to extract the target protein from insect cells. In a typical purification, starting from a pellet of insect cells culture, I suspend the cells in lysis buffer (50 mM TRIS pH8.5, 100 mM NaCl, 1% tween20, 1 mM PMSF, 5mM 2-mercaptoethanol and kept on shaking at 4 ⁰C. after that mix was spun down for 15 min at 10000rpm to remove insoluble particles. I am not able to purify my target protein. Can anyone suggest how to purify target protein from SF9 cells transfected with baculovirus?

    Sheetal Saini · Kurukshetra University

    hello mohamed

    i want to purify my recombinat protein from transfected cells and i am using the ^ His tag protein.

  • Shyamashree Banerjee asked a question in Microarray:
    In Microarray , can I pool in DNA samples for methylation study?

    I was planning for Methylation study using Microarray. If I want to pool in DNA samples what all should I keep in mind? Also, I have learnt that there might be some hindrance in the analysis of the results of Microarray, how should I take care of the same?

  • Jacob Cao asked a question in Sodium Bicarbonate:
    Sodium bicarbonate required to raise pH by specific amount?

    Hey everyone,

    I am running an experiment requiring ex vivo perfusion of the liver. The perfusate I'm running consists of 1.5 L gelofuscine and 750 mL autologous blood. 

    I'm trying to figure out how much sodium bicarbonate to add to normalise the pH of the perfusate (to 7.35-45) if I know the total volume and the current pH. If there's an equation I can use, that'll be very much appreciated.

    Thank you



  • Gyorgy Banhegyi added an answer in Epoxy Resins:
    In what ratio Epoxy Resin and Hardner should be along with Polymer to get the Good Mechnical Strength?

    I am making a sheet of Polymer(powder form) with the help of Epoxy Resin and Hardner, so what Ratio should i used of Resin and Hardner w.r.t to the polymer in wt%, for the High Mechanical strength polymer sheet ?

    Gyorgy Banhegyi · Medicontur Ltd.

    In most cases you should use the stoichiometric ratio between the epoxy and the active hydrogen (amine) to get the highest strength. Epoxy equivalent and amine content is usually given by the manufacturer. (The same is true for anhydrides). Slightly off-stoichiometric composition may still work but the Tg and the strength will be lower, perhaps the impact strength may improve somewhat.

  • Osman Doluca asked a question in Bacteria:
    What is the length range of 3'UTR and 5'UTR regions of E.coli genes?

    I found 3'UTR can be very large in eukaryotes however couldnt not reach any info for bacteria, esspecially e.coli. Any info on these matter?

  • How many cases of chronic abdominal pain and symptoms could be due to a thoracic disc hernia?

    How many cases of chronic abdominal pain and symptoms could be due to a thoracic disc hernia?

    "Francisco Javier Pérez Lara,J. Quintero Quesada,J. A. Moreno Ramiro,R. Bustamante Toledo, A. Del Rey Moreno, H. Oliva Muñoz. Chronic Abdominal Syndrome Due to Nervous Compression. Study of 100 Cases and Proposed Diagnostic-Therapeutic Algorithm. Journal of Gastrointestinal Surgery
    March 2015,Open Access"

  • Does anyone know more information on the Treaty of Sevres?

    In the treaty of Sevres there is an article referring to an Arbitration by Americans, more precicely the Woodraw Wilson Arbitration. Does this exist and whether it implicates land issues of Armenians?

    Lara Haladjian · University of London

    thank you everyone for your comments. i just wanted to know whether Wilson who gave the borders can still be applied today legally. i know the treaty does not exist since it was not ratified but the Arbitration may. its questionable. i shall look at the books youmentioned all

  • How can I visualize orthologous protein clusters in genome comparison tools?

    I have orthologous protein clusters from four metazoan. I dont't know the corresponding genome regions from where these proteins are derived. I can extract that with blat (if needed). I want to visualize these clusters on the graphics generated my artemis/mauve/mummer etc. Could someone suggest me which is the best tool for this and how can I do this?

    Maulik P Patel · Xcelris Labs

    Dear Ashmit ,

    Based on the ORTHOMCL group file you have to generate the matrix file for the same. You can generate the Venn diagram for Species specific and ortholog genes between species and the second thing you visualize through circos plot .

  • Anahita Farsaee asked a question in Blasting:
    Could anyone help me find an application of Poisson distribution in blasting or any other mining areas?

    I'd like to find a practical application not a theoritical one.

  • Can you suggest any appropriate research tool to assess early response during natural calamities in low resource countries?

    For assessing the early response of Government and other other supporting agencies during natural calamities, particularly, focussing on the devastating earthquake in Nepal. 

    Tulsi Bhandari · Pokhara University

     Thanks once again Chris Hafner-Eaton.

  • Osman Doluca asked a question in Bioinformatics:
    How do I prove functional role of a new regulatory element using bioinformatics?

    I believe I might have found a common regulatory element for a dozen E coli genes/loci, however I need to find further evidence, preferably using bioinformatics. Can anyone help show me how can I prove these genes are co-expressed or not? Is there any database for expression of e.coli genes? or any other means to provide further evidence that my element is real.

  • Is anyone working (Has anyone worked) on how Democratic Peace Theory can be applied to internal (not international) security, order and stability?

    I welcome suggestions/recommendations if anyone is working (has worked) on how Democratic Peace Theory contributes/does not contribute to internal (not international) security, order and stability?

    Srinivasan Rajamanickam · Pondicherry University

    Dear Safal,

    The 'negative peace' that you are referring to is not a confusion. It is the reality behind every endeavor by individual nations as well as the collective humanity through UN. Should there be something that you would like to call 'positive peace', if you reflect on it, you will find it as a corollary to the 'negative peace'.

    I presume you are familiar with India, particularly Kashmir and North East. Google the budget allocation for both these areas in the past twenty years and also check on the actual HDI achieved by these regions. You will find that despite huge allocations, progress and development have evaded these areas. Why?

    Take Sub Saharan Africa and see how much of funding has come from WB, IMF, EU, and AU. Despite colossal funding, the region remains one of the most backward in the world. Why?

    When you mull over both the answers above, you will find that the 'confusion' you are referring to is actually the reason why it is the most apparent reality. Order, stability and security -the terms that you have used in your question are actually the flip side of the 'confusion'.

    Hope this gives you some food for thought. Have a great day.