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  • How can I confidently decide if some variables are coming from a non-linear dynamic system?

    I am talking from theoretical perspective, by analysing the source and interaction. I feel like most of the things are from non-linear dynamic system even if the empirical evidence is not enough or states otherwise. Because, the accuracy of measurement can always be doubtable. My intention is to apply the ccm technique by Sugihara in order to find causal link between some variables.

    Akanda Wahid-Ul- Ashraf · Bournemouth University

    The problem is , the variables should not be negatively correlated as it is expected to have a positive relation . Because both of them should interact with each other and they should increase each others effect rather then decreasing. There might be a confounding variable causing this negative correlation. 

  • Marvin Pollum added an answer in Photodegradation:
    How can I Calculate Apparent Quantum Efficiency For Broad Band or Panacrhomatic Radiation ?

    I am studying photodegradation of Rhodamine B (RhB) dye under visible light irradiation. I want to calculate Apparent Quantum Efficiency of RhB degradation model. I have found an expression as follow  

    Apparent Quantum Efficiency (AQE) = (dx/dt)/(d[hv]inc/dt).  [ref: Chem. Rev.1995,95,69-96).

    dx/dt can be considered as rate of change in RhB concentration.

    (d[hv]inc/dt) can be referred as photon flux or total optical power incident on the sample.

    I need to find out d[hv]inc, for specific radiation intensity for example 10 mw/cm2.

    I came to know that it is easier to find out the value of photon flux d[hv]/dt for monochromatic source of light (single wave length radiation). However when incident radiation is broad band or rang of wavelengths, in this case how can i convert radiation intensity into photon flux. ?

    Thanks for having look on query !

    Marvin Pollum · Case Western Reserve University

    Chemical actinometry can be used to find the photon flux from a broadband light source:

    Chemical Actinometry (IUPAC Technical Report) Pure Appl. Chem., Vol. 76, No. 12, pp. 2105–2146, 2004.

  • Fiorina Giona added an answer in Childhood Studies:
    Excellent article, however what about safety and tolerability of High dose IM i.e. side effects?

    Excellent article, which shows preference of high dose IM over transplantation in pediatric CML specifically.However, side effects of high dose IM are not mentioned in abstract, if any. Can you elaborate safety and tolerability of high dose IM in children studied? Moreover, what maximum higher doses of IM can be used in children safely? Actually, I was discussing with Prof Saglio about higher IM doses in ped ALL (Ph+) as it is represented in about 25-45% of Pakistani ALL patients. Your answer will help me understand its feasibility.

    Fiorina Giona · Sapienza University of Rome


    If you are any question, please contact me by e-mail (giona@bce.uniroma1.it)

  • Al-Motasem I Aldaoudeyeh added an answer in MATLAB:
    How to simulate wind farm models in MATLAB environment?


    Where does this need to be initiated in the matlab environment ? Also any specific tutorial available ?

    Al-Motasem I Aldaoudeyeh · Yarmouk University

    Check these two videos:


    Also, you can type the following in the command window to open Simulink examples from MathWorks:


    From there you can see what components you expect to deal with and learn more details about their behavior.

    Many books explain some details about modelling. Some quite good examples are:

    Wind Energy Generation Modelling and Control. Lara

    Power Conversion and Control of Wind Energy Systems. Wu

    Doubly Fed Induction Machine, Modelling and Control for Wind Energy Generation. Abad

    Integration of Green and Renewable Energy in Electric Power Systems. Keyhani

    Solar PV and Wind Energy Conversion Systems. Sumathi

  • Hani Antoun added an answer in Actinobacteria:
    Where is the secondary metabolism of bacteria (include Actinobacteria) saved in cell?

    anyone knows where is the secondary metabolism of Bacteria (include Actinobacteria) located in cell?

  • Ronald Fricke added an answer in Fish Taxonomy:
    Can a fish person (marine biologist) identify this fish?

    from karachi

    Ronald Fricke · State Museum of Natural History Stuttgart

    Parapercis allporti has a significantly larger eye diameter, 56-60 lateral-line scales (P. robinsoni: 77-84), and is lacking the narrow orange lines on the head. Also the head shape is different, and the species is restricted to southeastern Australia.

    You would find a good photograph of P. allporti (and see the differences to the NW Indian Ocean species) in:

    Johnson, J. W. 2008. Pinguipedidae. Pp. 670-673. In: Gomon, M. F. , D. J. Bray and R. H. Kuiter (eds): Fishes of Australia's Southern Coast. New Holland Publishers. Melbourne, Australia. 1-928. 

    Therefore no need to change the previous identification as Parapercis robinsoni.

  • Paul E Harris added an answer in Monocytes:
    Could adding antibiotic may interfere with setting up a culture of monocytes?

    I want to start a culture of monocytes and have bought a cell line from ATCC.

    However, no pen-strep is mentioned in the culturing protocol - could it interfere with starting the culture?

    Thank you 


    Paul E Harris · Columbia University

    If these are human myelomonocytic leukemia cell lines they should be grown in pen/strep.

  • Matthew Clare added an answer in Carnivores:
    What factors are required for a top predator to evolve sociality?


    I am currently wondering what are the necessary factors for a predator to feel that group-living and performing altruistic behaviour are a better option than to remain living singularly, perhaps evolving into smaller carnivores or exploring new niches. 

    Basically why would a predator choose to become a pack hunter and why this option is preferable to the others. 

    Any help you can give is greatly appreciated. 

    Thank you 


    Matthew Clare · Lancaster University

    Thank you for your answers - and sorry for my late reply! 

    Maria a very interesting observation! Thank you for sharing! The European lynx certainly works like that - one of the major points for release into Britain was that it is an ambush predator and won't chase a prey animal for more than a few metres. Therefore farmers just need to keep a small stretch of land between their sheep etc and the forests. Good point about the environment shaping the hunting style of individuals, leading to a need for sociality, or not. Thanks!

    And an interesting point about the prey's defences being the obstacle Sylvio. Would certainly be a determinant in group size. Thank you! 

    And thank you for the papers René! Will get having a look. 

    Thank you everyone!

  • Is there any online server to validate my ligand based pharmacophore?

    I'm looking for server to validate ligand based pharmacophore 

    Eduardo Borges de Melo · Universidade Estadual do Oeste do Paraná

    Try the Zinc Pharmer


  • Xiao-Feng Gong added an answer in DOA:
    How can I resolve the coherent DOA estimation problem?

    How to resolve the coherent DOA estimation problem? i need brief answer asap.

    Xiao-Feng Gong · Dalian University of Technology

    Depends on what methods you want to use and what arrays you use. For example, if you want to use subspace methods, then you need to exploit some shift-invariance properties in the arrays. Then you need to look at the arrays that you use. If there is naturally a shift-invariance strcture in the array, like ULA and EM vector-sensor array, it can be easily be done via smoothing. If there is none such array, you may switch to the temporal structure or high-order statistics of the sources to look for this shift-invariance  structure. If you use large scaled array, maybe you don't need to do anything on the source dimension, instead, you may want to do hankelization on the space mode and use tensors. I think there are plenty of methods to deal with coherence, and this is totally dependent on the specific applications.

  • Paul E Harris added an answer in Proteases:
    Does anybody have experience to prepare lysate from intestinal tissue?

    I would like to make protein lysates from rat intestine to measure cytokines in the profile. Does anybody have a good protocol how to do that? I already found in the literature that intestine might have a lot of proteases and a special inhibitor cocktail might be needed.
    Thanks for your help!

    Paul E Harris · Columbia University

    Hi we use  a bead homogenizer , MPER from Pierce and HALT from Pierce when we look at proteins and phosphoproteins. be sure to wash the tissue well and cut up into 1-2 mm pieces. Bead homogenization in short bursts in the cold room. 

  • How do I keep my subject entertained during an offline tES/tACS stimulation?

    I'm interested in administering 10-15 minutes of tACS to participants before a visual short term memory task. I'd like to keep my participants entertained with eyes open (better for increasing the alpha power with my 10 Hz tACS) during this time, but I'm not sure what the best method of doing so might be as the literature often doesn't mention what the participants do during the stimulation period when the task is not being performed during stimulation.

    I currently think if I show them all the same 10-15 min nature documentary clip, any differences caused by watching might be standardized throughout the sample. However, as my visual task involves recalling color, I'm wondering if a black and white film clip might be a better choice. 

    Any advice or insight into what to show participants to keep them entertained during offline tACS? 

  • Hani Antoun added an answer in Actinobacteria:
    How to distinguish Actinobacteria from other bacteria and fungi on agar medium ?

    I am isolating Actinobacteria from plant rhizosphere on Agar medium. But i feel tough in differentiate Actinobacteria from others bacteria on agar medium. Can anyone help me what are characteristics of Actinobacteria on agar medium?

    Thank you.

  • Divyang Gandhi added an answer in Finfets:
    Is there any simulation freeware available for simulation of FINFET-based circuits?

    Mixed signal design at Schematic level with FINFET..

    Divyang Gandhi · Marwadi Education Foundation’s Group of Institutions

    Thank you sir

    But for Simulating FINFET based circuits, is there any EDA(like SPICE) tool?

  • Does anybody know the growth rates of facial SCC ?

    Would you consider SCC growth rates time dependent?

    Abrão Rapoport · University of São Paulo

    The SCC of the face has a time of growth equally of others location.After  6 months,occurs the duplication of the number of malignant cell

  • Juan Luis Santos added an answer in Climate:
    Do all low-pressure areas originate near paralel 60?

    This question should be easy to answer for a meteorologist but there is a lot of controversy among my friends (social scientists). We would appreciate any answer from an expert, no matter if you have time to answer just yes/no. Thanks

    Juan Luis Santos · University of Alcalá

    Thanks! According to some figures in their textbooks some of my friends thought low-pressure areas only started near paralels 60N and 60S, in addition to tropical cyclones. [http://www.tiempo.com/fotosrayo/Arcimis/arcimis41.jpg] Others tried to argue that meteorology is one of the most complex systems and we cannot say that low-pressure areas only appear near paralels 60, as you confirmed. Sometimes it is necessary to appeal to authority to finish endless discussions.

  • Andrey Luchnik added an answer in Risk Factors:
    Cancer a mere matter of luck? Or is there something under-appreciated?

    It has been all over in the news lately: The majority of cancer is obtained by bad luck, not by lifestyle or inheritance. See attached. 

    Really? The data appear solid and they make sense, but the conclusion seems a bit premature: the observations are based on established risk factors in the USA and I assume (let the experts please come forward!) that these risk factors are based on occurrence. This means we do not see all those cases where the patient's immune system adequately takes care of the anomaly. 

    How does occurrence of cancer relate to failure of the patient's immune system, and can we monitor this based on adequate biomarkers? How will the statistics and the conclusions change when this factor is included in the analysis?

    Andrey Luchnik · Russian Academy of Sciences

    Ones I recieved a letter from a scientist who lived in the USA. The letter began: "Dear Audrey!"

    The letters 'n and 'u' look very similar, but the sense is quite opposite.

    So 'ascitic tumor' means liquid state of tumor where everything is mixed and stirred in a belly like in a boiling soup or bouillon, especially when ill-fated animal moves. So "Tumor Ascitic Macrophages" should be permanently mixed with tumor cells "in the direct vicinity of tumors". But this is not the case in solid tumors, indeed.

    Probably "Ascitic Macrophages" means their presence in angiogenic or lymphatic vessels within and around solid tumors?

    Or I am devoid of sense in scientific terminology in English? Or may be I am too acid, acidic or "acitic" as is written about "Acitic Macrophages"?

    I think that a bit of 'hilarious' semantics would help to understand proper meaning of cancer. Is not it, dear Jan?

  • Dragana Čučak asked a question in Spectrophotometer:
    Is there a way to convert FAU (formazin attenuation units) or FTU (formazin turbidity units) to apsorbance?

    I am trying to make bacterial suspension of Aliivibrio fisheri which has turbidity of 10 FAU measured at 578nm. Is there some conversion between FAU/FTU units and apsorbance, because my lab  doesn't have turbidimeter which measures FAU or FTU units, and I can only measure by microplate spectrophotometer reader Multiscan go  which gives results as apsorbance?

  • Xuezhong He added an answer in CO2 Capture:
    What is the optimal capture efficiency of amine system based CCS technology?

    The cost of carbon capture is proportional to the amount of carbon dioxide to be captured from flue gas. If the percentage of CO2 to be captured is reduced below 90% (common CO2 capture efficiency considered) the cost of capture will also reduce. However, the amount of CO2 released into atmosphere will increase. Therefore, a tradeoff between amount of CO2 to be removed and associated costs should be deduced. In industry/generation plants such economic analysis is carried out prior to capture or CO2 is captured with an efficiency of 90% i.e, 90% of total CO2 in flue gas?

    Xuezhong He · Norwegian University of Science and Technology

    @Louis-César Pasquier, agree. the purity of captured CO2 is also important in the whole ccs process. in addition. different optimal CO2 capture ratio should be applied with respect to the technology used, e.g., amine, membrane, solid adsorption.  currently, it\s not necessary to capture more than 90%CO2, maybe 70-80%.

  • Xinping Wang added an answer in Herceptin:
    Antibody for HER2?

    Hi, I would like to ask some quesitons about the antibody of HER2. I found that there are antibodies called anti/HER2 or anti/ERBB2 antibody which is available by the company. And the other is Herceptin whichi is also a monoclonal antibody for HER2. Is there any difference among those? Meanwhile, if I want to find the antibody for HER2, which one is better for me. I hope you can also tell me some about the clone number which is frequently used for the research if you already have some experience of HER2.

    Thank you for all.

    Xinping Wang · University of Duisburg-Essen

     Thank you for Yung-Ming. I would do immunostaining. I have searched some literature and they are using different antibodied from different companies. Thus, I have no idea about choosing the antibodies for HER2. I have checked the hercptin on the website of Dako. Unfortunately, I did not find only herceptin antibody but there is the hercep test. For the antibody from Ventana, I found the clone number for the HER2. Thank you for your help.

  • Saleh Fallah added an answer in Machines:
    What is the physical explanation of the transmissibility ratio when it exceeds 1?

    The maximum value of force transmissibility to machine foundation in the nonlinear resonance frequency.

    Saleh Fallah · Tarbiat Modares University

    Dear Sir, in the vibrations, the vital parameter is ENERGY TRANSFER. In the case of resonance, maximum of energy is transferred to machine foundation. T>1 means that, the force transferred to foundation is higher than which applied. In the other words, because of resonance, input force is amplified and thus T>1 is occurred.

  • Arezoo sh. dadkhah added an answer in Hexanols:
    How to get liquid crystals using water, hexanol, and ctab?

    Is it just mix and you get lc phase or will there be any synthethic route or a procedure to do it?

    Arezoo sh. dadkhah · Tarbiat Modares University

    ·         http://www.tandfonline.com/doi/abs/10.1080/15421407108083556#


  • Alain Celzard added an answer in Langmuir:
    Is the isotherm model helps in predicting the group concentration responsible for adsorption?

    If the adsorption process is following Langmuir isotherm which gives a monolayer formation, Will it help in predicting the concentration of groups available which are helping in the metal removal.

    Alain Celzard · University of Lorraine

    You can only do a very very rough estimation, nothing rigourous. I really recommend additional techniques, e.g. TGA-MS, titration, XPS, ..

  • Rajaguru Sri added an answer in Natural Resources:
    What are differences between conservation and preservation of natural resources?

    The goals of these two terminologies differ not only with respect to their explicit
    and implicit long-term objectives, but also with respect to their justifications,
    their immediate targets and obstacles, and the strategies that are likely to achieve these targets

    Rajaguru Sri · National Institute of Ocean Technology, Chennai, India

    Explanation has given by many Scientist here. Anyhow conservation and preservation both are important in the present condition. Both are very difficult task with this industrialisation and civilization. Disaster is in high speed how to stop the disappearance  of biological resources that too in developing countries.

  • Noble K Kurian added an answer in Melanins:
    Uses of melanins?

    What would you do if you had pure melanin?

    Noble K Kurian · Cochin University of Science and Technology

    No answer ! As a melanin researcher I too is waiting for one answer..

  • Ta-Lei Chou asked a question in Thermoelectricity:
    Why do conventional heat-flow measurments for thermoelectric conversion efficiency require a bulky modules?

    To reduce the efficacies from thermal and electrical resistance in the heat flow Q?

  • How I can interpret adhesion data obtained from PF-QNM-AFM?

    I've used Atomic Force Microscopy PF-QNM mode to study changes of my crystalline material in high humidity conditions. During time the surface is changing and I see round clusters appearing on the surface. Clusters have lower adhesion force values that my material. There are two possibilities, either (A) my material undergoes  some kind of solid-solid transition (probably to hydrated form of my material), or (B) the water condenses on the surface and the round clusters are actually some kind of surface solution. 

    So if the clusters have lower adhesion which scenario (A or B)  is more plausible?

    And the second question is :can I directly relate the adhesion to surface energy? So can I say that the clusters that I see have lower surface energy than my crystalline material? Or is that I bit too big statement. This paper below relates adhesion with surface energy, but condition that they have had is 0 % RH to avoid any additional capilarry forces, but I I'm using 70% RH, so I'm not sure if this conclusion would be still relevant.


    Thanks in advance for any useful comments :)

    Monika Warzecha · University of Strathclyde

    Thanks everyone for all the suggestions! Thanks Pedro for suggesting the paper.