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  • Jay Dev Dubey added an answer in Economics:
    If i get a negitive Adjusted R2 in a OLS model, what conclusion should i draw from it. Does it because of too much variability in the data set (N=15)
    If i get negitive Adjusted R2 in a OLS model, what conclusion should i draw from it. I am thinking that it is coming because too much variability in a data set of only15 samples.
    Jay Dev Dubey · Jawaharlal Nehru University

    The conclusion will terrorise the entire academia.

  • Roland Pfützer added an answer in Obesity:
    Do you think obese people tend to have acute pancreatitis without having any etiologic factor fsuch as gallstone, hypertrigliseridemia?

    If obesity is an inflammatory condition and can be accepted as a causative condition for acute pancreatitis why all obese people dont have İt?

    Roland Pfützer · Klinikum Döbeln

    I consider it a risk factor which is probably a little bit of what you have in mind. As in many other diseases some patients will need to have several factors each confering a limited risk to develop acute pancreatitis. On the other hand there are some factors (presence of gallstones, high alcohol consumption) that confer a larger risk, but even in These patients additional factors may increase the risk for disease frequency and severity. 

  • Mahmoud Delphan added an answer in Fatigue:
    Does anyone have any reference about the role of cytokines on fatigue/exercise-induced fatigue ?

    Does anyone have any references or literature about fatigue mechanisms which cytokines are involved in it in none-disease subjects? Does anyone have any references about impact of cytokine on exercise/physical activity-induced fatigue or other immune system components and mechanisms which leads to fatigue delay during exercise/physical activity?

    Mahmoud Delphan · Tarbiat Modares University

    Mr. Dornels and Mr. Geiss

    Thanks for your interesting references. My focus were about fatigue delay during exercise/physical activity in non-patients that cytokines are directly involved in it !

    Best regards

    Merry Christmas, too.

  • Swati Panda added an answer in Tissue Preservation:
    Do the preservation chemicals affect heavy metal concentrations in tissues of preserved specimens?

    Fishes and benthic invertebrates are often preserved in alcohol and/or formalin/formaldehyde for future identification and sorting, compiling very large historical libraries. Does anyone know if these preservation techniques affect the tissues heavy metal concentration?

    Swati Panda · Institute of Minerals and Materials Technology

    Yes, the preservation chemicals affect the heavy metal concentration, but it all depends upon the type of chemical and heavy metal present.

  • Any ideas for a housekeeping gene for real time PCR on human DC?

    We are interested in examining the response of human dendritic cells to LPS with and without other stimulations, for a few genes of interest. The experiment is performed on human peripheral blood cells, without selecting for any population. We have seen that there is cellular proliferation, and are concerned that by using a "standard" house keeping gene like GAPDH, the results will be affected by the proliferation of other cells. Anyone have an idea for a general human DC-specific housekeeping gene with stable expression?

    Michael Appel · Assaf Harofeh Medical Center

    Thanks for the responses Holger and Remko. I didn't specify in my question-because it is somewhat open, but we are likely interested in pDC anyway.

  • Barbara Vogler added an answer in Virus:
    Time of "survival" of detectable RNA virus/ virus fragments in carcasses at -20°C?
    For logistical reasons I want to ask providers of avian carcasses to store the bodies at -20°C prior to sending them as a batch to our institution. Here I want to take samples of different organs which I will store at -80°C until analysis by PCR for West Nile Virus. Is there a guideline on how long such carcasses can be stored at -20°C without or with only minimal loss of potentially present west nile virus?
    Barbara Vogler · University of Zurich

    Dear Nabil,

    thank you very much for the information and the citations!

    I am sorry for the late reply, but I found your answer only just now.

    I wish you a merry christmas (if you celebrate it) and all the best for the upcoming year!


  • What is the best statistical program can be used for multivariate analysis?

    There are many statistical programs produced by software companies, enough to one should decide which software program is more fit to present and analyze the data. If we have data on ages of trees, size, growth rate, vitality, and seeds production. What is the best statistical program can be used for multivariate analysis for these parameters?

    Shuichi Shinmura · Seikei University

    I am very happy you and Mohamed send me your "Thanks".

    My suggestion is not enough about free demo version.

    I contact to obtain the permission to bundle trial CD with my books from JMP and LINDO Systems Inc.

    But researchers can down load those CD and can evaluate the functions etc.

  • Sanket Thorat added an answer in Asphalt:
    What is the trend of study in pavement material optimization?

    I want to write a paper about optimization of pavement material. I have tried to find related literature, but most of them are only about optimization in aggregate blending. I am considering the topic of asphalt content optimization.

    Is there anyone here can give "enlightenment" or brief explanation to me about the trend of study related to optimization in pavement materials?

    Sanket Thorat · Raisoni Group of Institutions

    I have read a literature regarding use of waste plastic as a binding material in pavement. Not sure if this is related to your query, but you can check this article.

  • Nurul Arneida Husin added an answer in Cell Culture:
    Is the use of a biological cabinet sufficient in a cell culture room (SP1)?

    We are going to set up a new cell culture room. What are the necessary procedures to avoid contamination?

  • José Avila-Peltroche added an answer in Alginate:
    What are the white dots on brown algae leaves?

    Does anyone know what is the scientific name of the disease (white dots) happens on the leaf of brown algae? How could it happen? Why should we remove the white dots by brushing while we are going to extract the alginate from this brown algae at the beginning step? Thank you.

    José Avila-Peltroche · Universidad Ricardo Palma

    There are bryozoans: a tiny animals that live in colonies. You have to remove them, like other epiphytic organisms, because they could affect the quality of the alginate or another compound. Also you could contaminate your sample with other non-algal compounds

  • Nurul Arneida Husin added an answer in SPSS:
    How does Support Vector Machine (SVM) is used for training siRNA dataset?

    How to classify siRNA sequences and how to train a dataset using SVM. Also what would be the best software for doing this. Whether SPSS v 16 support SVM or not. If yes please explain how to interpret. 

  • Jianhua Liu added an answer in Morphing:
    Can someone help with identifying colors in images of one individual bird?

    The images of interest is of a individual Eleonora's falcon. This species comes in different color morphs. 

    1. Light morphs (Male: yellow-greenish color around eyes and at the naked skin above the beak, Female: has blue/grey color instead of yellow-greenish).

    2. Dark morphs  (Male: yellow-greenish color around eyes and at the naked skin above the beak, Female: has blue/grey color instead of yellow-greenish).

    3. Homozygous dark morph (Female: no yellow-greenish color around eyes and no yellow at the naked skin above the beak and complete black bill/mandible). 

    The plumage is dark so I could exclude "light morph", but it could either be a dark morph male or female, or it could be a homozygous dark morph (female). 

    See the different images of the same individual (except IMG_3165 and IMG_0575 is a image for comparison, this individual has for sure yellow-greenish around the eyes and at the naked skin above the beak).

    To find the color morph of this one individual bird, is it possible to perform a analyze to identify if there is yellow-greenish around the eyes and at the naked skin above the beak? Similar, is it possible to identify if the bill/mandible is complete black? 

    Note for my question: In this case I only want to classify this individual bird on the images (newly edited this to make my question clearer). 

    Could the image lie, hence yellow at the image but not in the real world?

    For me it looks like there is some yellow-greenish around the eyes and at the naked skin above the beak, although quite pale. If so it would be a dark morph male. 

    A reference paper about the color morphs could be found here:


    I'm not skilled in image analysis and I hope to get some help.



    Jianhua Liu · Beijing University of Civil Engineering and Architecture

    If your photos are cinfined as the offerd above, yellow-greenish color, blue/grey color, etc., the approach based on "scan line algorithm" for you may be a feasible method.

  • Shubham Jain asked a question in Curcumin:
    What is the effect of U.V on Curcumin.??

    I am working with Curcumin and i kept curcumin sample(Polymeric sample loaded with curcumin) for U.V sterilization up to one hour.After 1 hour sample turned into light yellow which initially it was dark yellow.
    So, i want to know that is there any changes in activity of curcumin after exposing to U.V.
    Thank you.

  • Siti aishah ahmad fuzi asked a question in Etching:
    Anyone knows the recipe for etching the silver in AAO template?

    i want to etch (remove) silver (Ag) from AAO template.Based on finding in internet, to etch silver, we need HNO3 and H2O. i need suggestion from others about the ratio@percentage on using these chemical. 

  • Wojciech Kopec added an answer in Gromacs:
    Gromacs installation on centOS cluster error, help please?

    I'm trying to install gromacs on linux cluster centos6. After successful installation I got an error for not finding pdb2gmx command. It seems like that it is for not addressing executable file Pathway. I used #whereis gromacs to find the installation location and making an address by PATH command, but I find this massage "no such file or directory". what should I do?  


    Wojciech Kopec · University of Southern Denmark

    You can control where to install GROMACS with the flag 

    default is (/usr/local/gromacs), where you replace xxx with the path to your desired location. After the installation the command "source /xxx/bin/GMXRC/ should do the trick.

  • Antonio Rosato asked a question in Circular Dichroism:
    What is the best way to fit Circular Dichroism Data of a pH titration?

    Hi to all,U of a protein in order to monitor its secondary  structure changes by means of Far-UV Far- Circular Dichroism.

    I'd like to extrapolate thermodynamic Data. For example the free energy of unfolding of the protein.

    I have plotted the pH variation against the molar ellipticity at a certain wavelength, and I got a sigmoid-like distribution of my data.

    What kind of function would you use to interpolate these data?


  • Aled Jones added an answer in Nurses:
    Which countries or regions currently use laws or regulation to determine safe staffing levels of nurses to patients?

    Please provide examples of ratios used, skill-mix or other means that have been used to set and monitor nurse staffing levels. Thanks.

    Aled Jones · Cardiff University

    Thank you Rafael. I will read with interest. 

  • Moiz Masood added an answer in Solar Power:
    In PSIM, how to simulate solar module to see I-V and P-V curves?
    I tried, but couldn't get the required results. Can you reply? It is very important and urgent.
    Solar Cell I-V and P-V Characteristics in PSIM.
    Moiz Masood · Korea Electrotechnology Research Institute-KERI

    check your email inbox i have sent both.

  • Can someone suggest conceptual frameworks developed by now, for carrying capacity estimation?

    Please share your experiences and information.

    Nadia Abbaszadeh Tehrani · Iranian Space Agency

    Dear all,

    Thank you for your kind answers. A s you see most of your recommended sources related to  recreational carrying capacity. But I am looking for a  general framework ,before we decided what kind of  ecosystem we want to apply  the concept . 

    Please read my paper " UCCLN model" . You can find  it here in my publications.We have introduced a general framework  applicable for all kind of ecosystems ( like  considering the equation of  source= sink  or entropy rate and resilience......) ,then we applied  it  for urban ecosystem by choosing right indicators ;There is a general framework  that guide you  from : choosing indicators to weighting and ranging them.I want to find more similar works and studies.

    Thanks again  and best wishes    Nadia

  • Sachin Vyas asked a question in Sudan:
    What is the proper procedure for preparations of SUDAN BLACK B dye?

    As i need to check organism producing oil, i want to stain it with SUDAN BLACK B, please tell me the proper solvent and exact method to prepare it.

  • Tom Gierstberg added an answer in Iterative Methods:
    What is the most efficient iterative method for solving linear systems when the matrix dimension is very large and full of zeros?

    I would like to solve a system of equations for a relatively large matrix dimension (around 300 times 300). The matrix is full of zeros and several of the iterative methods that I used didn't converge (GMRES and Jacobi). I failed also to solve it using the direct method because some of the elements are very big and the determinant exceeds the maximum size. I would appreciate it if someone here could suggest one iterative scheme that is suitable for such systems, very large, with many zeros. Thank you.

    Tom Gierstberg · ASML

    Hallo Abdallah Daddi Moussa Ider,

    Are you sure that you have a correct formulated problem, because, based on the info you have given, it looks like you have an ill conditioned and spares matrix.

    Can you do singular value decomposition on you matrix?

    A matrix of 300x300 is relatively small. Direct solvers would be able to solve it without any problem.

    Best regards.

  • Shalini, Agarwal asked a question in Autistic Children:
    What parameters one should consider when designing interiors of school for autistic patients?

    want to study on interiors of schools for autistic children so what should i consider while designing interiors for them

  • How do we go about Sequencing data analysis after SDM?

    I had done one amino acid mutation using SDM, and had sent the transformants for sequencing using self desgined primer. Now Iam little confused as to how to analyze it. 

  • Smriti Sahu asked a question in Beer Lambert Law:
    What is the formula for the absorbed light intensity for a solid sample?

    Beer Lambert's law is not applicable to solids. Then how can one find the absorbed light intensity for a solid sample?

  • Raghuram Tr asked a question in pH:
    What is the value of sensitivity factor β for Si3N4 layered Ion Sensitive FETs ?

    Hi all, 

    According to the Site Binding model for Ion Sensitive FETs, the surface potential is related to pH as given by the following equation:

    Ψo = 2.303(kT/q) (pHpzc - pH) (β/β+1)

    where β is the sensitivity factor. Could any please provide the value of β for Si3N4 layer in ion sensitive FET devices?



  • Anyone knows a little information about scaphanderidae and it,s clasification ?

    I need some information about scaphanderidae but i could not find useful information

    Mohammad Hasan Gerami · Gonbad Kavous University


  • Elnaz Ghanbary asked a question in Accuracy:
    Accuracy below mm with bumblebee?

    hello every body.

    have you had experience working with bumbleebe?

    to which factor i should pay attention in order to obtain accuracy below mm?

    thank you all

  • Nurul Adhwa HAR asked a question in Alexa Fluor:
    Alexa Fluor versus DyLight?

    "Alexa Fluor® 488 dye conjugate showed a 15–30% better signal-to-noise ratio than the DyLight™ 488 conjugate" - How true is this? Does anyone have an experience that says the opposite? Do Alexa Fluor dyes actually perform better than DyLight dyes?

  • HARI KRISHNAN RAMACHANDRAN asked a question in Humans:
    Various existing models of human beings?


    What are various existing models of human beings?

  • Hemjyoti Kalita asked a question in Polymers:
    How do we determine the processing temperature of amorphous polymers?

    For melt mixing technique