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  • Daniela Fuchs asked a question in Theobromine:
    Are there any studies about how our diet could help preventing Alzheimer's dementia?

    Since there is no cure for Alzheimer's disease yet, prevention seems to be important. Are there any studies, which are suggesting a preventive effect of (green) tea, coffeine, theobromine, nicotine, ingredients of the Mediterranean diet

  • Alain de assis rosa asked a question in Crowdfunding:
    What is your attitude towards Crowd Funding project creators?

    Participate in my online research and you will assist me in determining what impact, if any, a Crowdfunding project creators identity has upon potential contributors. The research requires 250 respondents, so your assistance will be greatly appreciated.  Please follow this link to participate: http://crowdfundinglab.weebly.com

  • Victoria Ruiz added an answer in Nitrocellulose:
    Why do I have sample curvature in the low part of my electrophoresis gel?

    Hello everyone, 

    as you can see, I have troubles with my western blot assay. This is a nitrocellulose membrane dyed with Ponceau S. The lowest part of the membrane has a curvature in each sample lane and I don't understand why. Sockingly, the molecular weigh standard it's ok in this part. I'm doubting about the samples origin (the samples are from rat liver) or the current during the electrophoresis (nevertheless, this should affect the molecular standard also). The acrylamide percentage of this gel is 10% so the problematic part it's between 10 to 37 kDa

    Thanks in advance for your help!.

    Victoria Ruiz

    Hi again,

    I've changed the current limit during the electrophoresis and I got this result (maximum voltage permited was 200V instead of 500V) . I think the problem was that. However, I think I could limitate it more. Which current do you recommend me? I usually run the gel at 50mA, 25mA each gel and I think I should change the maximun voltage permited. 

    Thanks in advance :)

  • Cherry Ann Mañago asked a question in Poetry:
    What is poetry?



    -point of view



    -rhythm pattern


  • Tanel Vahter asked a question in Arbuscular Mycorrhiza:
    Is there a good reason, why i should not add antibiotics to MSR medium for an axienic in vitro arbuscular mycorrhiza culture?

    Hi everyone,

    I am currently trying to get a root-organ culture going with field-collected spores. I am using a transformed chicorey root and MSR media. I am having problems with the surface sterilization of spores, probably due to insufficient duration, as i keep having bacterial growth in cultures. As a side thought, i started wondering, is there a good reason why i shouldn't add streptomcin sulphate to the MSR medium, to control any bacteria that might survive the main sterilization process? If this is ok, what concentration should i aim to use? I cant seem to find definitive literature on this.
    Thank you in advance,

  • Deana Zainal added an answer in Statistical Methods:
    Can someone suggest a good statistical method to do rainfall analysis?

    i need to analyze rainfall data in which I want to Identifying the frequency of rainfall relationship with the amount of rain.. Is there any good statistic method that i can use to identify this??

    Deana Zainal

     dear Anand,

    thanks for ur attachment link.. its really help me :)

  • Ana Bento added an answer in Special Education:
    What is the history of special education in America?

    Research paper on inclusion

    Ana Bento

    sorry to answer with a question,but what do u mean by special?

  • Denis Feather added an answer in Mixed Methods:
    Any advice between a case study or mixed methods design?


    I'm writing my master thesis and have a bit of trouble with choosing method. The study is a follow-up study of QI-interventions. I'm using QUAN measures to see if the interventions lead to changes and if eventual changes were sustainable. Depending on the results of QUAN I'm going to do focus group interviews (QUAL) and try to find out what happended and why. So far so good (?). Now to my concern: is this a multiple case study or is it a mixed method study with explanatory sequential design? If this is considered to be a case study - what is the benefit of doing a case study vs "only" a mixed method study?

    Thankful for your opinions!

  • Andreas Schmidt added an answer in Proteomic Analysis:
    Can I use fold change instead of expression (intensity values) in co-expression network?

    Hi ,

    can i use fold change instead of expression value for coexpression network construction analysis? We have performed global proteomic analysis between 3 condition (1)control 2) disease A and 3) disease B ). Objective is to check the differences in the PPI.

    (Note: we have same set proteins between both the disease only difference is fold change)

  • Sujoy Sarkar added an answer in Carbon Materials:
    How do I characterize materials using EIS Spectroscopy?

    I'm researching carbon materials for counter electrodes application in DSSC . I read several articles related to my research topic. In the articles, authors said they used EIS spectroscopy for make nyquist plot. How to characterize materials using EIS Spectroscopy? I have to characterize the DSSC or counter electrode layer?

    Sujoy Sarkar


    May this article give you the reason behind using EIS for DSSC.

    Electrochemical Impedance Spectra of Dye-Sensitized Solar
    Cells: Fundamentals and Spreadsheet Calculation


  • Sumit Dhawane added an answer in Jatropha curcas:
    Can any one share me experiences on bio fuel development using physic nut as a feed stock?

    physic nut is one of the feed stock used for bio diesel production. We are planning to go through for the development using this feed stock.

    Sumit Dhawane


    I have worked on the biofuel production, but before answering to your question let me know, what exactly you want to seek information about. 

    1. Extraction of oil from seeds.

    2. conversion of oil into biofuel

    or any ither information??

  • Nobuhiro Takeuchi added an answer in Artificial Respiration:
    Is there any possibility that epidermis staphylococcus may be a cause of sepsis in a healthy individual?

    Here is the case that I need your advice. A 41-year-old female was brought to our emergency department with high fever and conscious disturbance. Her vital signs on admission suggested that she was in a state of septic shock. Laboratory data showed elevated liver and renal function, and coagulation abnormality. Two set of blood culture revealed the presence of coagulase-negative staphylococcus (afterwards the microbe turned out to be epidermis staphylococcus). Close inspection of the patient showed that she had scratched skin eruption in her legs and hands. Her past medical records did not include diabetes mellitus. She did not take steroids or anti-cancer drugs. She was not considered to be in a state of immunodeficiency. Intensive care, including artificial respirator, dialysis, and aggressive therapy of anti-bacterial drugs, saved her in the end. I learned that, basically, epidermis staphylococcus is a weak microbe which usually affects infants or immunosuppressive individuals. I could not find articles or researches which wrote about healthy individuals who were inflicted by sepsis resulted from epidermis staphylococcus. I believe that blood culture was not a contaminant. I suppose that microbes entered into bloodstream from the scratched wounds. Is there any possibility that epidermis staphylococcus may be a cause of bacteremia as well as sepsis in a healthy individual?

    Nobuhiro Takeuchi

    I appreciate your help, Dr Easow, Dr Iqbal, and Dr Borodach.  

    Here is the more detailed information regarding the patient.

    On day 4, trans-esophageal echocardiography was performed. There was no evidence of IE.  

    Sputum culture revealed staphylococcus aureus (GPC) and streptococcus sp (GPC).  Cerebrospinal fluid culture revealed no presence of bacteria. Urine culture revealed no presence of bacteria (except a small colony of gram negative bacilli). Unfortunately, no sample of skin culture was taken.

    With respect to her skin legions, we consulted with a dermatologist. She has a history of childhood atopic dermatitis. Skin lesions were seen only in her hands and lower legs; dry and scratched skin like xerotic eczema. Her skin lesions did not seem like Stevens-Johnson syndrome. She did not take medicine including over-the-counter drugs.

    No evidence of immunosuppressive state was found (HbA1c was within normal limit and, serum anti-HBV-Ag, anti-HCV-Ab, and TRHA were negative).

    Our treatment included the administration of antibiotic drugs (CLDM, PIPC, and ABPC/SBT) and IVIg, dialysis, and respiratory management. 

    If more information is needed, I am willing to give. Thank you!  


  • David Romera asked a question in PDMS:
    How can i clean a PDMS stamp from any biological rest (proteins, bacteria, even fungi contamination?

    If anyone knows a standard protocol for cleaning would be great!

  • Rafael Silveira e Silva added an answer in Legislative Studies:
    Could anyone help to find experiences about using Qualitative Comparative Analysis (QCA) in the field of legislative studies?
    I found a lot of research with the use of QCA in studies on management and business organization and some studies that have applied this method to comparing democracies. However, I still can not find application of QCA in legislative studies.
    Rafael Silveira e Silva

    Thank you, Prof. Thiem! It was very useful!

  • Medkour Hicham added an answer in HFSS:
    How could PIN diodes be inserted in patch antenna geometry for frequency reconfigurability issue using HFSS?

    Using HFSS, I want my patch antenne resonate in more than one frequency by switching the PIN diodes, but like what shall I insert these diodes( How can I model them in HFSS) what are the steps?

    Medkour Hicham

    Thanks Anvesh that's what I was expecting to do thank you indeed

  • Lars Krause added an answer in Water Stress:
    How do I stain a leaf?

    I would like to know how to stain leaves or how to observe anatomical changes of leaves in response to water stress, using a light microscope.

    It should be a very rapid and simple way; I do not want to know such fixation, dehydration or embedding of plant samples. 

    Lars Krause

    Maybe Aniline Blue staining is a good solution for you. The stain helps you to visualize callose deposition which is a stress indicator. There is a lot of (old) literature out there for different Aniline Blue stainings. 

  • Imène Bayach added an answer in Hydrogen Bonding:
    Is there any other tool apart from AIM to analyze hydrogen bonding?

    According to AIM analysis (and also my software viewer),  any HB exists. However, the interatomic distances between the H and O atoms are less than 2.5 A. How can I be sure that they are not HB?

    Imène Bayach

    Dear Prof Rafik, thank you very much for your kind answer and the time you spent to write this detailed informations. With the software viewers (vmd and Avogadro), I can not see the dashed line indicationg usually the HB. I never tried PyMol, I will try it. I will also look  what DSSP and STRIDE can do. Thank you very much. Sincerely 

  • Sudip Mukherjee added an answer in Hela Cells:
    What if I incubate hela cells in PBS?

    Hi to all,

    I need to incubate a plate of hela cells in a solution of PBS (without Mg and Ca). Is it dangerous? do PBS cause detachment or morphology changes of the cells if I incubate them for 30 min in this buffer at 37 °C?

    thank you

    Sudip Mukherjee

    In PBS 15 minutes to 30 minutes the cells will remain alive. If you want to keep for more time better you use phenol free HBSS buffer. Up to 1 hour you can keep your cells intact in this particular buffer.

  • Muhammad Israr khan added an answer in Cover Crops:
    How can we justify the increase in Toatal Microbial PLFA and Total bacterial PLFA (Gram positive and Gram Negative) after cover crop incorporation ?
    1. we cultivated cover crops during winter season which was harvested and was incorporated in to the soil as a green manure one week before the rice cultivation.
    2. To check the effect of cover crop incorporation and seasonal effect we got great increase in the total PLFA, Bacterial PLFA and Fungal PLFA after the cover crop incorporation during rice cultivation season as compared to fallow winter season.
    Muhammad Israr khan

    Hi Xiaobo Li!

    Due to the fact that PLFAs are known to degrade rapidly in soil after cell death, it is not likely that PLFAs from the green manure material contributed significantly to the soil PLFA profile in our study, especially since sampling was not carried out immediately after amendment

  • Zhai Yang asked a question in Protein Sequencing:
    What is low complexity region in a protein sequence?Is it indispensible ?

    I clone a toll like receptor gene in a species, but I found that when I used SMART to predict its protein structure, it lacked a low complexity region compared to other species. Is it indispensible? 

  • Robert Ose added an answer in Fluorescence:
    Is there any membrane-impermeable cell tracker (tracer) which shows fluorescence only inside the cell?

    I'm searching for a cell tracker/tracer which is non-fluorescent outside the cell and cannot cross cell membranes freely. Once the dye is brought inside the cell it should remain there and gain fluorescence.

    Has anyone worked with something like that?

    Thanks in advance

    Robert Ose

    thanks for the answers so far.

    Currently i'm not quite sure if PI is suitable for my purposes. I'll work with live cells with intact membranes. If I bring PI inside the cell, Is PI able to cross the nuclear membrane if the cell is intact and consequently show fluorescence?


    I was searching a lot for celltracker probes but I couldn't find any matching my criteria:

    Either the Celltracker is membrane-impermeant but shows fluorscence independt of it's location or the Celltracker gains fluorescence inside the cytosol (cleavage by esterases e.g.) but is also cell-permeant.

    I couldn't find any which is cell-impermeant and shows fluorescence only if it's inside the cell (cytosol preferentially).

    Kind regards


  • Attila Lehotzky added an answer in Molecular Biological Techniques:
    Is there a problem with the Green and Sambrook recipe for a 10M Ammonium Acetate solution?

    A copy of what is printed in the fourth edition of "Molecular Cloning" by Green and Sambrook can be found here: http://cshprotocols.cshlp.org/content/2006/1/pdb.rec8067.full?text_only=true.

    I tried this protocol and had trouble. First, I tried adding 77g NH4AcO to 70mL H20 and ended up with ~135mL of solution (so it was already over 100mL). Second, it took ~10minutes to stir in the last bit of salt...adding more seems like it might take awhile to get into solution, if it will even go. Has anybody successfully made a 10M ammonium acetate solution using this protocol?

    Attila Lehotzky

    the calculation is ok. i suppose the salt is hygroscopic highly (contains a lot of water if older) if i remember well.

  • Dimis Poulos asked a question in Quantum Entanglement:
    When will we establish photon pair quantum entanglement instant communication with distant stars and galaxies?

    probably we can't go there but we can talk with

  • Günter Becker added an answer in Bayesian:
    If we want inference to be driven solely form data, why do we even bother specifying a prior? What is the sense of a so called "uninformative prior"?

    What is the raison d'être of uninformative priors? Isn't one of the Bayesian goals that of allowing to systematically incorporate prior information into inference?


    Günter Becker

    No prior is uninformative in the strict sense of the word. There are only priors which minimize the information supplied in comparison with the evidence. If there is no evidence, there is nothing, which could dominate the effect of the prior.

    You use an uninformative prior, if you have no prior information at all, but still would like to use Bayesian framework. Bayes without a prior: this simply would not work

  • Wu Yongyan added an answer in FLUENT:
    How to use UDF under symmetry boundary condition in Ansys FLUENT?

    I'm modelling open channel flows by commercial software Fluent. I've set the surface as symmetry boundary condition, now I want to change the dissipation rate at this boundary,but UDF seems to be unactivated under symmetry boundary condition. How can I realize this idea in Fluent?

    By the way, I also tried to use DEFINE_SOURCE to change the value of dissipation rate near the boundary region, but in Ansys Help Guide, it is said that you can use DEFINE_SOURCE to specify custom source terms for the different types of solved transport equations in FLUENT. I guess the source term is added to the dissipation rate transport equation, rather than the dissipation rate value in certain region. So I think this idea is unfeasible.

    Thank you very much for discussing with me and providing suggestions!

    Wu Yongyan

    Dear Kalal,

    Thank you very much for your suggestions!

  • M.J.W. Cock added an answer in Lepidoptera:
    Can any one tell me the genus or species of this snout moth ?

    I think it belongs to Hypeninae (Erebidae:Noctuoidea). I found the larvae feeding on leaves of coffee in Colombia. Please look at the photos of the adults (male and female in dorsal and lateral view), the larva and pupa.

    + 5 more attachments

    M.J.W. Cock

    Now that image strikes a chord.  Either it's Gonionota melobathes Walsingham (Oecophoridae, Depressariinae) or something very close to that. With that clue, I see that Dan Janzen and his group have reared some Gonionota that look like yours: http://janzen.sas.upenn.edu/Wadults/resultsexpressNAME.lasso?-SkipRecords=60&output=337&herbivore%20species=gonionota

    Regards, Matthew

  • Zubayer Ibna Zahid asked a question in Research Topics:
    Can anyone help me with some literature on load transfer mechanism of inclined reinforced concrete column between two floor plan?

    I have searched but not getting any literature on the above topic. I need some some literature on inclined column research? Also I want to know the scope of future research on this topic. 

    Your help is very much appreciated. 

  • Norah A . asked a question in IT Security:
    PKC or SKC or lightweight security ?

    PKC, SKC or lightweight security

    what is the most appropriate for the IoT sensors? and why ?

    thank you..

  • Dilip C. Nath added an answer in Curve Fitting:
    When fitting data to an isotherm, which type of regression is more reliable, linear or non-linera curve fitting?

    In fitting the data with linera and nonlinera isotherms what is the exact difference which makes linear regression more favorable,most of the papers use linear form of the isotherm. 

    Dilip C. Nath

    There are so many types of non-linear form. Try step by step fitting polynomial curve --e.g. Linear, quadratic, cubic  and so on. Apply test then proceed for higher degree. One such method is Orthogonal Polynomial fitting.