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  • What will be the bioavailability rate of plant polysaccharides?

    Would like to know the pharmacokinetic profile of the plant polysaccharides. If any one have worked on it, kindly comment.


    Thanks Dr.Sardina and Dr.Ali for the suggestions and references.

  • Ion sensitive microelectrodes

    Hi, I am looking for a partner lab specialized in ion sensitive microelectrodes in order to exchange experience and opinions! 

  • Saeid Safavi asked a question in Linguistics:
    What are the main differences between children and adult speech?

    I know that this question is too general, but I want to get opinions on the possible ways to split these differences into several groups, eg. “Acoustic and linguistic differences”.

    Thank you very much in advance.


  • Antonio Bova added an answer in Patient Rights:
    Who owns patients' health information?

    According to the Freedom of Information Act, American patients can access their health information upon their request. The above applies to the US as far as I know.

    I wonder if there is a global consensus over this issue? Do other countries have a similar legislation?

    In my country, doctors can refuse to show the patients their own information. They believe and say that the doctor and not the patient owns the patient's information. Is it legal? Is it ethical?

    Antonio Bova · Universiteit Utrecht

    The majority of health related Internet searches by patients are for specific medical conditions. Typically, they are carried out by the patient before the clinical encounter to seek information to manage their own healthcare independently and/or to decide whether they need professional help, and after the clinical encounter for reassurance or because of dissatisfaction with the amount of detailed information provided by the health professional during the encounter. I do believe that it is important that health professionals acknowledge patients’ search for knowledge, that they discuss the information offered by patients and guide them to reliable and accurate health websites.

  • How does one improve the adhesion between SiO2 and InGaAs, SiO2 and Pt?

    Hi, when I use SiO2 onto InGaAs (2um width pattern) as the wet etch mask it usually falls off, I am wondering how to improve the adhesion between them..

    Another issue is to deposit SiO2 on the Pt, we found the SiO2 layer is also easy to fall off, suffering..

    Wojciech Kołodziejczyk · Wroclaw Medical University

    Did you try find binding energy for such complex?

  • Nikola M Stojanovic added an answer in Mice:
    Acetic acid induced writhings in mice?

    I asked similar question some time ago and i want to try to get the help once more! During experiments with abdominal writhing induced with acetic acid very different results are obtained! In the same group (control with vehicle) large discrepancy in number of writhing is observed? Also different publications are saying that in 20 minutes the animal has like 100 wriths! That is unbelievable for me! I have never seen more that c.a. 45 wriths during 20 minutes!

    Nikola M Stojanovic · University of Niš

    We had also problem with extremely jumpy mice :D Thanks any way 

  • Lynn Egan added an answer in Acids:
    How can you digest/dissolve plant matters with acids?

    Is it possible for H2SO4-HNO3 solution dissolve/digest small debris of dried plant matter, and how long it takes to completely disintegrate them? Will heating helps to digest the plant matter with this acid solution?

    After some trials, I found that the plant matters are tough to be digested although both acids are strong corrosive agent. Someone suggested me to use Piranha solution, but H2O2 is not available is my lab and it is quite expensive.

    For your information, I'm trying to remove those plant materials present in my beach sand samples to recover microplastics particles. I think that Piranha solution may digest the microplastics

    Appreciate your feedback. Thanks.

    Lynn Egan · Hach Company

    You may have to do some work upfront, if you do not want to include plastics in the digestion.

    Kjeldahl digestions are often used with plant materials.  However, this is done at temperatures of 380-390 degrees (with salt, acid and a metal catalyst like copper or selenium) and your plastics are likely to melt.  (The end result of this digestion allows measurement of Total phosphorus, as well as ammonia and organic nitrogen).  

    A persulfate digestion can oxidize carbon , nitrogen, and phosphorus.  I do not know though, if it might also digest plastics.  Particle size is likely to be important- larger particles would be harder to digest.  The digestion can be done in an autoclave under acidic or basic conditions depending on what you are trying to recover. 

    The biggest difficulty will be that digestions for plant materials will digest organics. Plastics are carbon compounds and likey to be digested to some extent.

    Good luck!

  • Li Ma added an answer in Apoptosis:
    What method to screen apoptosis without a spectrofluorometer?

    I need a screening method to screen apoptosis in cell cultures. I have an idea that could be interesting but I need some preliminary data to decide whether it make sense to ask my PI to invest on my idea or not. My lab is specialized in biochemistry, molecular biology and proteomics so I have all I need to perform Western Blot, ELISA or Real Time PCR. I also do have a spectrofluorimeter but it's not a 96 well plate reader. For the microscope... well, let's assume I don't have one, because the one I have it is barely enough for cell counts :D
    If my idea proves right I can ask to use other's laboratory equipments but I first need some preliminary data!
    I tried an ssDNA ELISA kit but it was really terrible (the kit itself, not the data).
    Any other suggestions?

    Li Ma · Stony Brook University

    Here is what we use: Cell Death Detection ELISA plus Kit from Roche (Cat# 11920685). It is good for screening. It can detect both apoptosis and necrosis.

  • Vishakha Maskey added an answer in Questionnaire:
    Can someone recommend a secure, free, online tool for gathering questionnaire/survey data?

    I am looking for a secure way to gather questionnaire data online. Preferably it would be relatively easy to use...and free? (the free version of Survey Monkey is too short)

    Vishakha Maskey · West Liberty University

    I have only used Quartics and survey monkey. I understand it has limited free access. Thanks for the information on Limesurvey.  If its open source, is it secure? It looks like it has limited capability in terms of statistics but I can't say much since I haven't used it yet. Good luck!

  • When will an infinite ascending union of context free languages result in a context free language?

    Let A be a finite set.  Suppose for each natural index i, there is a context free language Ci over alphabet A. Suppose further that for all indices I, we have Ci is contained in C{i+1}.  The project is: to find conditions on {Ci} so that the ascending union of the Ci  is still a context free language over A.

    Note that at each stage i, a pumping lemma is satisfied, as will be Ogden's Lemma, and etc.  So, one might need to work hard to find a good ``finiteness'' condition that would do the job.

    Collin Bleak · University of St Andrews

    Dear R.C. Mittal,

      Could you be a bit more explicit about necessity and sufficiency?  I am very interested in your answer.

      Best Wishes,


  • How to choose a proper blocking reagent, when I am using a goat origin antibody?


    I'm experiencing problem with WB when I use an antibody originated from goat. I have read that since goat and bovine are close related, it is highly possible that the anti-goat secondary antibody reacts with milk or BSA. Is there some standard way to block the membrane, so that I don't get cross-reaction between bovine protein and anti-goat antibody?

    Thank you very much

    Fulvio Celsi · IRCCS Ospedale Infantile Burlo Garofolo

    You mean your primary ab is raised in goat? try with blocking with fish gelatin, that would help. 

  • Lóránd Silye added an answer in Molecular Codes:
    How can I got the Electronic Foraminiferal Atlases and Databases?

    Dear sir/ Madam,
    I read some were about Electronic Foraminiferal Atlases and Databases “Through office-based and mobile electronic devices (computers, ipads, iphones etc) anyone can now access an increasing number of atlases and databases that assist in the identification of foraminifera and provide vital information about their geographic and stratigraphic ranges, their molecular codes, their classification, type localities and type species etc”. where these databases were available and How can I got it?

    Lóránd Silye · Universität Bremen

    Have a look here: http://www.marinespecies.org/foraminifera/

  • Nor Zuhaidah Mohamed Zain added an answer in ICF:
    Collaborators for the Development of a mobile application to use the ICF (International Classification of Functioning, Disability and Health)?

    If you have an interest in disability and chronic health conditions, would like to collaborate on an interesting mHealth project using the ICF, please take the survey at the attached link: https://www.surveymonkey.com/s/mICF

    Nor Zuhaidah Mohamed Zain · Rasmi Universiti Pendidikan Sultan Idris (UPSI)

    I have taken the survey as well.

  • HIF1alpha Western-Nuclear Extraction Help

    For HIF1 alpha western blot, while doing the nuclear extraction, on following the volumes in the protocol (100ug tissue and 300uL solute) protein concentration in the samples prepared is too low. Can I increase the tissue weight to increase the sample concentration? Would that result in incomplete lysis? 

  • P. Pardha-Saradhi added an answer in Mitochondria:
    Why can't oxaloacetate pass through inner mitochondrial membrane?

    In Malate-aspartate shuttle oxaloacetate first convert to malate and then pass inner mitochondrial membrane. in matrix of mitochondria oxaloacetate regenerated from malate.

    P. Pardha-Saradhi · University of Delhi

    Basic purpose of malate-aspartate shuttle is to transport reducing power (NADH) generated in cytosol into mitochondria. This shuttle involves two antiporters - one exchanges aspartate with glutamate and the second one exchanges malate with alpha-ketoglutarate. It is obvious that there is no oxaloacetate transporter or oxaloacetate-malate shuttle. To the best of my knowledge oxaloacetate is synthesized and its threshold level is maintained in mitochondria to take care of Kreb's cycle and synthesis of linked organic molecules (in particular keto-acids needed for synthesis of amino acids etc.) .

  • Yu Li asked a question in Foxes:
    Can anyone send me this paper "From third pole to north pole: a Himalayan origin for the arctic fox"

    written by Xiaoming Wang et al.

  • Albert Calbet added an answer in Copepods:
    Can you help me to identify this copepod?

    This is from java brackish estuary.

    Albert Calbet · Spanish National Research Council

    The upper one looks like Parvocalanus crassirostris, although you should take a closer look to the appendages. The lower one seems a cyclopoid. To help you in your future identifications I am sending to your address a pdf of a taxonomy book about copepods from indian waters.  Good luck!

  • Cytochrome c release - WB identification.

    Does anybody have some experience in western blot analysis of cytochrome c release? Especially in the context of human cancer cells? Maybe you can recommend some good antibodies? Thanks a lot!

    Dilruba Ahmed · Karolinska Institutet

    Hi Emilia, I have used Cyt c antibody from BD Bioscience which was quite good. I was studying mitochondria mediated apoptosis in Human Hepatocellular Carcinoma cell lines. I don't know any fast way of detection but doing confocal microscopy is a very good opotion if you have the facility. Good luck. 

  • Fulvio Celsi added an answer in BLAST:
    Anyone has come over a weird melt curve and gel image from real time RT-PCR?

    I have been trying many times and still failed to give single peak in melt curve. I have designed a new primers to detect all 6 variant of my target gene. Please refer to the blast result as attached. I have done Ta optimisation but the result is weird. My desired PCR products should be 137bp but the gel image didn't match. Final concentration for both forward and reverse primers are 0.5uM. The one step real time RT-PCR is as below:

    Cycle 1: (1X)
    Step 1: 42.0 °C for 30:00.
    Cycle 2: (1X)
    Step 1: 95.0 °C for 05:00.
    Cycle 3: (40X)
    Step 1: 95.0 °C for 00:10.
    Step 2: 60.0 °C-65.0 °C for 00:30.
    Data collection and real-time analysis enabled.
    A: 65.0 B: 64.8 C: 64.2 D: 63.3 E: 62.0 F: 61.1 G: 60.5 H: 60.0
    Cycle 4: (1X)
    Step 1: 95.0 °C for 01:00.
    Cycle 5: (1X)
    Step 1: 55.0 °C for 01:00.
    Cycle 6: (61X)
    Step 1: 65.0 °C-95.0 °C for 00:10.
    Increase set point temperature after cycle 2 by 0.5 °C
    Melt curve data collection and analysis enabled.

    Fulvio Celsi · IRCCS Ospedale Infantile Burlo Garofolo

    Dear Shin

    so..what you mean by substrate is clean? 260/280 >1.8? is that correct? 

    you can try to increase the starting RNA, going up to 500ng in step to check if your specific band increase...could be that your mRNA is low expressed. Try also to find a positive control (i.e. cell line/treatment taht would increase your G.o.I.) that will be specially important for gene expression measurements

    also I would try to increase at least to 65°C to check if you get better specificity..I would not recommend to make assumptions about gene expression with 2 peaks (as the one I saw..)

  • Antonio Bova added an answer in Photographs:
    Could you please let me know about any research on psychology of photography?

    Some more specific questions would concern: photographer as the creator, photographing process - stages, characteristic, psychological situation of the person being photographed, and many, many others. 

    Antonio Bova · Universiteit Utrecht

    Hi Joanna,

    here I found an interesting article:





  • Wei-Kan Chu added an answer in Materials Research:
    Bulk nanostructured polycrystals: Why have they been largely neglected by materials researchers for more than 100 years?

    Indicator: Their reported synthesis and characterisation are hardly available in the scientific literature and university textbooks on materials science and engineering inform us almost nothing about them.

    Wei-Kan Chu · University of Houston

    Science knowledge grows exponentially with time. Most of the things we know today were discovered or developed over the past 150 years. Flow of knowledge stared with simple concept first.  What is electron? What is atom?, what is solid, what is single crystal solid? Then get into variation and complication such as crystal dislocation, grain boundary, and so on and so on. Curiosity on nano crystal is a high level luxury question before we understand the primary question. The timing for nano-science and technology is ripe when the precursor knowledge and curiosity are ready and the technology need is also pulling.

  • Muhammad Akmal added an answer in Trout:
    What do you think about unilateral exophthalmia in Rainbow trout?

    Recently I observed a new Unilateral exophthalmia in affected rainbow trout fish during infectious mortality in coldwater fish farm in suspected fish.

    The rate of mortality was sharp and sudden mortality was occurred.

    What do you think about main causative agent in this outbreak?

    Muhammad Akmal · University of Veterinary and Animal Sciences

    you should have to perform some tests for confirmation of exact type of pathogen responsible for this

  • Milo Gardner added an answer in Geometry:
    Can you suggest some books with exercises related to Euclid's Elements, or to Euclidean Geometry?

    as an aid to an undergraduate course on Euclidean Geometry and its history?

    I need exercises that involve not complicated proofs.

    Milo Gardner · California State University, Chico

    Geometry as taught in the 1950s was more a logic course than a math course. Theorems, postulates and corralaries were memorized that lead to Q.E.D. proof conclusions. Several math fundamentals based on rational number arithmetic were required to be mastered before geometry was taken. Geometry was taken after Algebra I and before Algebra II. A senior math year studied trig and solid geometry. Today the above math and logic courses are taught in a different structure and sequence. Solid geometry, for example,  is only implied by a pre-calculus course.

    Without knowing your background and math goals, no specific geometry book can be recommended.

  • What is the difference between the BET total pore volume and the total pore volume calculated based on skeletal and apparent density?

    The total pore volume (Vt) was calculated based on the following relationship:

    Vt=1/dapp - 1/ds

    ds= Skelet density; dapp= apparent density

    The macropore volume was then estimated from the equation below:

    Vmac = Vt - Vmes - Vmic

    Vmac = macropore volume; Vmes=mesopore volume;  Vmic= micropore volume

    In fact, can i calculate Vmac from the total pore volume which obtained by BET test?

    Behzad Shiroud Heidari · University of Tehran

    Thanks for your helps, specially Mr.Celzard


  • How can i do a regression with categorical variable no binary?

    Hello, i tried using the binary logistic regression in spss,the following error message is being shown


    The dependent variable has more than two non-missing values. For logistic regression, the dependent value must assume exactly two values on the cases being processed.
    This command is not executed.

    The DV has 5 categories:
    1,00= No player
    2,00 = social player
    3,00= risk player
    4,00= pathologic player
    5,00 clinical pathological player

    Could you please help me.

    Best regards

    Catarina Pinto · University of Porto

    I´ve tried and i got this message:

    The number of dimensions requested for the Observed and Predicted Frequencies table has exceeded the limit (20) of the pivot table subsystem. Therefore, this table will not be produced.
    There are 1482 (92,9%) cells (i.e., dependent variable levels by subpopulations) with zero frequencies.
    Insufficient memory to complete the model estimation step.
    This command is not executed.

    Am i doing somthing wrong?

    Best regards,


  • George Zorinyants added an answer in Tidal Waves:
    Is it known for tidal waves to create a shock wave or any sound?

    A tidal wave passes two times per day around Earth. This means, the lateral speed of the wave peak is extremely high, something like 1700 km/h at equator, which is higher than speed of sound in air. 

    It is known for supersonic objects to create a shock wave and extremely loud sounds. Yet, I never heard of sounds induced by tidal waves, or of any shock waves. Are there any effects of such quick waves?

    Also, what is the resonant frequency of longest range waves in World Ocean? Are the tidal waves slower or faster than resonance?

    George Zorinyants · Cardiff University

    Thank you Marshall Eubanks,

    1. Rotation of Earth at equator is 40 000 km per 24 hours=1667 km/h. This is a supersonic speed in air (I admit, not in water).

    2. Individual molecules of water move with thermal speeds v=sqrt(3kT/m), which is, if I am not mistaken, something like 2300 km/h - a lot more than the speed of sound in air. Still, probably it is insignificant to talk about speeds of single molecules, but rather we should consider speeds of macroscopic elements of water. These, obviously, move rather slowly. At least everyday experience does not show any fast moving waves. I am struggling to understand how a slowly moving water can give rise to such a quickly moving tidal bulge. What is a trajectory of a macroscopic water element? do they move up and down, or sideways, or do they spiral around Earth? Do tides lead to global flux of water around Earth?

    3. It does seem to be a very complicated problem. Still, I was very naively thinking, if the frequency of longest range waves is much lower than 24 hours, they should be nearly pi delayed with respect to the driving force (moon attraction and centripetal "force"). But we have the two forces with exactly pi offset with respect to each other. Does it perhaps lead to some sort of phase matching condition? Is the bulge on the opposite side of the Moon actually caused by Moon attraction, but terribly delayed?

    Sorry for being so amateurish!

  • Otto Lappi added an answer in Cognition:
    Can anyone give me examples of real-world tasks where 'habitual motor responses' or 'response inhibition' play a role?
    I am looking for examples of real-world tasks (e.g. jobs, situations, etc.) where habitual motor responses are a factor, for good or for bad.

    For example, a situation where a simple motor task or response is performed many times in rapid succession, until it becomes 'automatic', and then when there is eventually a need to withhold from performing this task/response it is difficult to do so.

    Any help would be much appreciated.
    Otto Lappi · University of Helsinki

    If you learn to drive using a stick shift, you are very likely to hit the brake pedal when manoeuvering with an automatic, e.g. at  a car park. (You need to make sure your "clutch foot" keeps away from the pedals - this may take some effort at first).

  • Jose A. Ramos asked a question in Electronic Nose:
    Looking for electronic nose input-output sensor data for system identification

    Is there anyone who needs to do system identification on electronic nose sensor data? I'm currently trying to model an electronic nose sensor and need input/output data to test the model. I am also looking for collaborators and people who know how to build these circuits. I would like to learn how to build one from scratch. We have NI-ELVIS II+ equipped with NI Digital Electronics FPGA Board and the Freescale HCS12 microcontroller add-on. I am teaching electronics and would like to start tinkering with these types of sensors but would like to know where to start. There is so much literature out there that it's hard to find a starting point. I should be able to do all the data analysis including calibration since that's my field of research. Any help is appreciated. 

  • Which is the best method for the biofouling control the biofouling in artificial structures

    I want to culture scallops and oysters in lanterns