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  • Isabel Hutan added an answer in TiO2 Nanotubes:
    Mechanical property of anodic TiO2 nanotube?

    Please tell me about the mechanical property of anodic tio2 nanotubes, are they fragile, if they are how can I make them rigid?

    Isabel Hutan · Istanbul Technical University

    Thanks Mr.Rahul Krishna

  • Jiri Koubek added an answer in Acrylamide Gel:
    What is the voltage or ampere for running DNA or PCR products in acrylamide gel?

    Usually, we perform SDS-Page in acrylamide gel and we use SDS buffer. If I use 1x TBE buffers for DNA or PCR products for running in acrylamide gel what will be the power/running condition?

    Jiri Koubek · Academia Sinica

    You cannot control everything. Potential and current are bound together with the resistance of your gel (which you can assume a constant).

  • Cheng Wei added an answer in Gas Flow:
    How can I define and extract the side-blown jet penetration depth?

    In the side-blown flowing process, with the increasing of gas flow, the gas flow regime will be jet flow, the jet flow is shown in figure 1. However, how do you define and extract the side-blown jet penetration depth?

    Cheng Wei · Central South University

    dear professor. many thanks! i will try to caculate the average value as soon as possible to figure out the relationship. Hope continue to get your guide.

  • Ravi Kant Upadhyay added an answer in Fasciola:
    Are there any papers on Fasciola incidence, prior to Triclabendazole use?

    I am looking (and struggling) to find basic research on fasciola transmission and incidence rate prior to the global implementation of Triclabendazole. 

    If you have or know of research papers - also of transmission/incidence rate -post- Triclabendazole use, that would be very useful too.

    Many Thanks, :D 

    Ravi Kant Upadhyay · Deen Dayal Upadhyaya Gorakhpur University

    Liver fluke disease (fasciolosis) is caused by the trematode parasite Fasciola hepatica. Disease can result from the migration of large numbers of immature flukes through the liver, or from the presence of adult flukes in the bile ducts, or both. Liver fluke can infect all grazing animals (and man) but mainly affects sheep and cattle. It is most pathogenic in sheep. It is important to use the appropriate drug for each situation and to base treatments on fluke forecasts. Most flukicidal drugs on the market are effective in treating chronic fasciolosis, because they kill adult fluke, but few are effective in treating acute fluke infections in sheep caused by the immatures migrating through the liver. Triclabendazole (TCBZ) is generally the drug of choice but as resistance to flukicides can occur with repeated and frequent use, alternatives should be used wherever possible, particularly in late winter and spring, in order to reduce the potential for the development of TCBZ-resistance. The use of combination fluke and worm products should be discouraged as it can lead to off-target selection for resistance to broad-spectrum anthelmintics in nematodes, or fasciolicide resistance in F hepatica. However, there is evidence that closantel-BZ combinations have a synergistic activity that may enhance their activity against resistant F hepatica (and H contortus), and also help delay the emergence of resistance to either class of compound

  • Jiri Koubek added an answer in Papillomaviruses:
    Why about 20% of cervical cancer patients are anti-HPV protein negative?

    For cervical cancer, it is infected by human papillomavirus that contain two structural proteins and other oncoproteins. But there are about 20% of patients are anti-HPV16 E7 negative. However HPV16 E7 protein is oncoprotein. Why is it? Could anyone give me the answer? Thanks. 

    Jiri Koubek · Academia Sinica

    It is purely statistics and antibody reactivity. Antibodies anti-HPV16 E7 are reactive with E7 protein from HPV 16 and 18 which are the cause of approximately 75 % of cervical cancer. The remaining 25 % are caused by some other factors, such as HPV type 31 and 45 or smoking. And we cannot be sure that we know all the causes of cervical cancer.

  • Wiwat Wanicharpichat added an answer in Matrix:
    Can we approximate any matrix to an idempotent matrix?

    Is there any possibility to approximate any general/square matrix to an idempotent matrix?

    Wiwat Wanicharpichat · Naresuan University

    Gregory L Wilson given the correct answer.

    In fact  every singular matrix is a product of idempotent matrices.  See:

    Araujo, J., Mitchell, J. D.: An elementary proof that every singular matrix is a product of idempotent matrices. Amer. Math. Monthly 112, 641–645 (2005)

  • Eugene H Chung added an answer in QRS:
    What QRS duration should be considered abnormal?

    A recent recommendation indicates that the QRS complex on routine ECG should be considered abnormal is its duration is of 120ms or more. I saw a young women of 150cm height and 45kg weight with the QRS duration of 110ms and a men of 195cm height and 100kg weight with the QRS duration of 120ms. Actually, who of them had abnormal QRS duration?

    Eugene H Chung · University of North Carolina at Chapel Hill

    Clinically, I would call up to 110 msec (as measured on the widest QRS seen on the ECG) within normal, 110-119 IVCD, and 120 and over either IVCD or LBBB/RBBB (if QRS morphology meets criteria).

  • Can you recommend a Free Text Mining tool?

    I would like to know what free online text mining tools I can use for user profile?

    Margarethe Born Steinberger · Universidade Federal do ABC (UFABC)

    I've been working with NLTK for applications of Corpus Linguistics in Portuguese.

  • Is Neural network coupled with genetic algorithm for finding developmental disorder based genetic pattern alterations clinically reliable?

    Any published studies or labs working on this will also help!

    Walid Yassin · Kyoto University

    Thank you for your answer.

    JFTR. Yes, I meant general reliability, as for data size i could use as much data as i can from the data bank (Not too much to cause overfitting), the parameters typically comes from EBM, the network structure will most probably be a multilayer feed forward, but I'm not sure, yet as i am still investigation the worth of going into the analysis. Anyway i know what you mean, but i saw in pubmed that they did use this to check for tooth eruption in paediatric population, patient classification for some trials, even to infer genetic population structure from certain molecular markers, and i was wondering why hasn't it been used for disorders like tourrett, schizophrenia and autism genetically (logically i thought it would be very suitable).. Is it because, no one tried? or that we can only state the output  as a hypothesis no more? or... etc. 

    The value of using neural networks along with genetic algorithm in this sense (Just thinking about the logic of it) made me question the absence of such kind of publications in this area of research. 

  • Does anybody know how many examples of modeling of primary productivity are available?

    VGPM- Vertically Generalized Production Model

    SeaBAM model

    Leonardo Alvarez Santamaria · Autonomous University of Baja California Sur

    There are many models to calculate primary productivity, it all depends on what are you looking for, some a empirical some analitical, some work for open ocean waters, others for estuaries.


  • Does these two angles in schmid factor contribute to 90 degrees when considering ΤC = σy cos φ cos λ.?

    In regard to schmid factor the two different angles are complementary to each other?

    Tarik Ömer Oğurtani · Middle East Technical University

    That is completely wrong statement.  If this would be the case, which is not !  any smart person having some simple notion in trigonometry could write the following set of equations.

    İf  φ+λ=90   Then

    TC=  σy cos φ cos λ.=σy cos φ cos (90-φ)=σy cos φ sin φ=σy/2 sin 2φ

    In general the force acting on the dislocation line at any given  point can be written in the following fashion:

    F = t . sigma . b,  [unit in cgs:   dyne/cm]  Where  b is the Burgers vector, t  is the local unit tangent vector of the dislocation line,  sigma is local second order stress tensor or matrix, which is symmetric. In crystalline solids the  directions of the Burgers vectors (or the slip directions) and  the slip planes are not arbitrary, which are fixed by the crystal structures. 

  • Abhas KUMAR Maharana added an answer in Azocasein:
    In the Protease assay, which substrate (Azocasein or casein) and method should be taken?

    I followed some literature concerning the protease assay but I am a little bit confused about what substrate should be taken for the assay. Yes, casein is cheaper than azocasein, but is there any differences among them. Both are universally accepted or not? Thanks in advance for your replies.

    Abhas KUMAR Maharana · Orissa University of Agriculture & Technology

    Thank you all for valuable suggestions.

    Dr. Katarzyna Styła, can you send me the full text of the publication you mentioned in the answer?? 

  • Hemantkumar Naik added an answer in Bioactivity:
    Do you know any enzymes that is bioactive in fatty acids (like lipid or oil)?

    Usually enzymes are soluble in water, but I am interested some enzymes that function in fatty acids?

    Hemantkumar Naik · Millannium Research Laboratories, Inc

    I have worked on CANDIDA antartctica Lipase B. Being immobilized on to polymer, it is active in organic solvents as well.  It depends on which type of enzyme you are looking for.  Some enzymes are active at the aqueous/organic interface to some extent.  I have tried alcohol dehydrogenase using aqueous/organic solvent mixture.  I got good results depending on the solvent combination and their ratios.

    Good luck

  • Abhas KUMAR Maharana added an answer in Pseudomonas:
    Does anyone have advice on lipase activity with tributyrin agar?

    Ttributyrin agar has been dissolved 20 g in 1 litre distilled water and  sterilized by autoclaving at 121°C for 15 minutes. It has been cooled to 80°C and added 10 g neutral tributyrin. But we couldn't see a clear zone, even by Rhodococcus spp. and Pseudomonas spp.

    Abhas KUMAR Maharana · Orissa University of Agriculture & Technology

    Yes you are right  Viraj Yele. Now days researchers try rhodamine B agar plate method also. I got good results from that. ALL D BEST...

  • Goodwin G. Jinesh added an answer in Western Blot:
    Why do my western blot bands are coming out like this ?

    The extreme right lane is the marker.... rest all samples.... all sample bands are coming in m- shapes.... need expert comments and help in troubleshooting.

    Goodwin G. Jinesh · University of Texas MD Anderson Cancer Center

    Try loading tip for loading samples with concentrated loading dye such as 5x or 6x (Sample volume should be low but concentrated enough). Keep the tip at the bottom end of wells while loading samples. I guess you use regular tips for loading samples.

  • Ahmed K. Sadek added an answer in Spectrum Sensing:
    Do you have any suggestions on channel estimation techniques in the SU to FC links for coorperative spectrum sensing?

    In cooperative spectrum sensing, the knowledge of the channel gains between each secondary user (SU) and the fusion center (FC) can help improving the overall sensing performance. However, it seems to me that conventional channel estimation techniques cannot be applied since these channels have low bandwidth. In fact, it is of paramount importance to save resources in the reporting channels, even for the task of reporting the SU's decisions in itself. It seems that any channel estimation process will go against this principle of saving resources. Any comments? Thanks in advance. Dayan

    Ahmed K. Sadek · Qualcom

  • Mrityunjay Tyagi asked a question in Media Preparation:
    Why does Penicillin concentration is given in Units and not micro grams per mL ?

    In cell culture media preparation, Penicillin is given in Units while the Streptomycin is given in micro grams per mL. 

  • Wilhem Smith asked a question in ATM:
    What is Future ATM Concepts Evaluation Tool?

    Future ATM Concepts Evaluation Tool, I search the internet and there is no sign where I can use it, is it classified?

  • Roberta Price asked a question in Quantitative Methods:
    Sampling size for nonprobability sampling?

    Descriptive research design, quantitative method, and purposive sampling

  • Yuan-Yeu Yau added an answer in Camels:
    Could mushrooms survive in wild on animal stools?

    I have found 2 mushrooms in Makkah, Saudi Arabia..I was very astonished to see these mushrooms in a very poor soil !! after analyzing the habitat, I have found high rate of camels stools in this area where these mushrooms are growing.. could mushrooms survive on animals stools?

    please could anybody identify these mushrooms?   

    Yuan-Yeu Yau · Northeastern State University

    Hi Ammar,

    Yes, people already grow edible mushroom on compost with some animal manure (dung) or animal wastes. See the paragraph and photos of "Growing Agaricus bisporuson this website: http://www.botany.hawaii.edu/faculty/wong/BOT135/Lect020.htm

    Attached is a picture of the Common Mushroom (Scientific name: Agaricus bisporus.)

  • How can I confirm that a copolymer formed between two monomers which reacted ?

    We need to confirm that a co-polymer is formed and the monomers are reacted.   it is not a simple blend of two monomers.

    Hemantkumar Naik · Millannium Research Laboratories, Inc

    I would go for NMR (1H and 13C), FTIR (may be may be not), DSC and MALDI.  These will give you all information you need.

    Good luck

  • Ed Klotz added an answer in Integer Programming:
    How to measure the difficulty of a Mixed-Linear Integer Programming (MILP) problem?
    The intuitive answer is the number of binary variables, when solving the MILP through the branch-and-cut algorithm. But, is the number of binary variables really the main characteristic that increases the computational burden of an MILP?

    In the case of the Unit Commitment problem (UC), it has been proven that including the startup and shutdown binary variables decreases its computational burden in comparison with a UC using only commitment binary variables (without the startup and shutdown ones).

    So if the quantity of binary variables does not directly influence the computational burden of a UC, how to measure the computational burden of an MILP problem?
    Ed Klotz · IBM

    Those are nice examples, Sandor.   In the context of the branch and cut algorithm, they are predicated on the expectation that the LP relaxations solved for the larger problems don't  require significant additional runtime that exceeds the gain on the MIP side that you described.    But, given the (weakly) polynomial worse case behavior of LP, and likely exponential worst case behavior of the branching process, that probably isn't an issue in many cases.   And, branch and cut is not the only possible algorithm that can be used when discussing the difficulty of solving MIPs.

    Also, I think the nature of the increase in problem size plays a role here.   If  you increase variables without increasing constraints, you make more activities available to satisfy the constraints.   This can make the problem easier to solve.   Set partitioning comes to mind here.   If you make additional subsets available to do the partitioning, you may turn a difficult model with few or no solutions into one with many solutions, some of which can be found easily.   

    If you add constraints associated with additional requirements (as opposed to constraints designed to tighten the existing formulation) without adding variables, you reduce the number of feasible solutions, potentially making the model more difficult to solve.    So, there are tradeoffs involved here.  In Sandor's harvesting example above, I think that tradeoff is favorable for the larger model.   Many more activities are available, while few, if any, additional restrictions are imposed.  

    Another example that illustrates that size doesn't matter involves cutting stock problems, which often appear in the paper industry.   You can come up with a nice, compact formulation that is extremely weak and symmetric, resulting in long run times.   Or you can come up with a strong formulation that involves a huge number of variables.   But, because the number of requirements for the model stays modest, column generation can solve these models effectively.   

  • Michael W. Marek added an answer in Anxiety:
    Is there any questionnaire that considers the role of a teacher in creating test anxiety in English learners?

    I want to examine the test anxiety in English learners and find out whether a teacher can be a possible source of anxiety from students' point of view.

    Michael W. Marek · Wayne State College

    I have seen some papers about "demotivation" in which certain behaviors of the teacher reduce the motivation of students. That is not the same as teachers causing test anxiety, but there may some similarities about things a teacher does increasing or decreasing test anxiety.

  • Jimmy Gao asked a question in Trend Analysis:
    How can I use R software to perform the Mann-Kendall Test for trend analysis and abrupt change

    I want to use daily precipitation data to analysis the trend of rainfall.Thanks.

  • What are the paramagnetic and ferromagnetic natures of nano-crystallites and of a bulk system?

    1) 'If experimentally a system (nano-crystallite) is paramagnetic in nature'. Can we conclude the bulk to be paramagnetic too or is it possible that the bulk results may suggest ferromagnetic nature?

    2) Also I would like to know the theory behind "Why paramagnetic nature suggests non half-metallic nature"?

    Moayad Flaifel · National University of Malaysia

    If your material is at nanoscale size, then what you may think as paramagnetic may be a superparamagnetic behavior that resembles to the former at room temperature. However, you can confirm the paramagnetic phase by getting the Curie temperature at  which magnetization drops off to zero. If so you may need to carry out a zero-field cooling measurement to trace where exactly the magnetic phase transformation occurs at lower temperature and hence below that point you will uncover the original material's magnetic phase that is supposed to be at when it is in bulk form.

  • Is it possible to test syntactic understanding without requiring semantic knowledge?

    Naive question from a non-linguist. The basic distinction between syntax and semantics is clear; but I'm not sure how one might assess a person's understanding of syntax without requiring some degree of semantic knowledge. Even in jabberwocky sentences (which have English grammar and syntax but with nonsense words), the so-called "nonsense"words do suggest meaning. I'm interested in examples of "syntax without semantics" in both music and language. 

    Luisa Isabel Rodríguez-Bello · Universidad Pedagógica Experimental Libertador

    If you work at a sentence level, maybe we can have an understanding of syntax without requiring some degree of semantic knowledge, in the sense that the sentence is properly structured or grammaticaly correct (Chomsky’s "Colorless green ideas sleep furiously"). At a text level, some semantic knowledge will be required (words, propositions, theme, etc). But, since the reference affects the syntax, the pragmatic knowledge (anaphoric and cataphoric relations, etc.) will be essential.

  • Chinpiao Chen added an answer in Pd/C:
    Are there any suggestions for removing a CBz group from an amine in the presence of a thioether and an ester?

     Pd/C and PtO2 up to 60 psi of H2 give no reaction. Hydrogenation in the presence of sulfur.

    Chinpiao Chen · National Dong Hwa University

    Please try the mixyure of Pd/C and Pd(OH)2/C. Ref. Chem. Pharm. Bull. 57(12) 1421—1424 (2009)

  • Dr A. Kumar added an answer in Optical Properties:
    Which optical properties and specification considered most in choosing optical limiter polymer?

    Which companies introduce these material such as ZnTPP?

    which specification is in more importance for these devices?

    Dr A. Kumar · Harcourt Butler Technological Institute

    Wavelength dependence of refractive index of polymer should be responsible for abberation effect.