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  • Nenad Atanasov added an answer in Tibia:
    Is still theire is indication for conservative treatment of nondisplaced tibia fracture in young adult ?

    Is still indication of conservative treatment of nondisplaced tibia fracture in young adult ?

    Nenad Atanasov · Clinic for Orthopedic Surgery, Ss. Cyril and Methodius University, Skopje, Macedonia

    Conservative treatment is still a method of choise in some non-displaced tibial fractures, Use of ring fixator is however very useful not only in improvement of bone healing, but in correction of bone alignment and deformities, as well.

  • Giulia Salgari asked a question in Touch:
    Does anyone have a "bubble task" in E-Prime?

    I'm starting a new project on DMD subjects and I need to create a  simple "bubble task" on E-Prime where as the bubbles come in the subject has to touch them on a touch screen. 

    Does anyone have a similar script that I can use as template?


  • Jean-Christophe Domec added an answer in Drought:
    Is there any relationship between boron and drought resistance in the higher plants ?

    plant physiology

    Jean-Christophe Domec · Bordeaux Sciences Agro

    When you mentioned drought resistance, did you mean resistance to drought-induced cavitation? If yes I do not see why there should be a correlation..

  • Aditya Chauhan added an answer in Shape Memory Alloys:
    How much energy can a NiTi shape memory alloy release during martensitic transformation?

    During martensitic transformation the alloy absorbs and releases energy. How can I estimate this energy or latent heat? 

    Aditya Chauhan · Indian Institute of Technology Mandi

    Go through this paper. I hope it helps.

  • Tausif Alam added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Tausif Alam · University of Wisconsin–Madison


    1. Very likely true

    2. Almost certainly rubbish

    3. Highly speculative gobbledygook  ;)

    Of course when one begins with a statement regarding mind with "stuff", anything is possible.  ;)

    I think that you tend to make things overly complex - either you are way ahead of me or perhaps lost.  ;)

  • Eyal Akiva added an answer in Phylogenetic Tree:
    Constructing phylogenetic tree

    Hi every one

    I am wondering if any of you can suggest a reliable program to align 1184 protein sequences as I want to construct my tree using maximum likelihood

    Appreciate your valuable suggestions  .   

    Eyal Akiva · University of California, San Francisco

    Hi Narjes,
    In order to generate a reliable tree, you need a very reliable multiple sequence alignment.
    I’d also suggest a smaller set to begin with (max 100 sequences), so you can compare between your preferred ML method and bayesian (e.g. MrBayes).
    You may try to reduce redundancy of very similar sequences using CDHIT.
    After constructing a well-resolved tree from the manually-curated MSA 100 sequences, you may try an ML method (e.g. FastTree) applied on your 1,148 sequences and compare your results with your well-resolved, small tree, since fast methods that are capable of such big trees should be considered with care.

  • Nikki Malhotra asked a question in Patient Engagement:
    What are some (successful) ways to engage physicians in using Telemedicine?

    Telemedicine is a growing trend, however the use of telemedicine is still not wide spread. I am doing some research in finding ways to engage physicians in using Telemedicine.

    Patient engagement has been successful in using telemedicine, however, it's the physicians that need to be the initiator and driver in using this technology.

    Any help from the experts in this area will be greatly appreciated.

    Thank you.

  • Jean-Christophe Domec added an answer in Drought Stress:
    Which one is more important for constructing water conserving plants?

    Most of the water loss from the plants control by the function and the number of the stomata. Which one (stomatal aperture or stomatal density) you think is more important for water use efficiency and also drought tolerance by plants?

    Jean-Christophe Domec · Bordeaux Sciences Agro

    I believe that stomata aperture is more important because the range of variation and control (from zero when fully open to the maximum pore size when fully open) can vary with environmental variable (VPD, soil moisture), whereas density is fixed.

  • Krishna KUMAR Meher asked a question in Heat & Mass Transfer:
    Why there is an anomaly in the thermal conductivity of Aluminium and Uranium at high temperatures?

    It is a question which I encountered during my class on HEAT AND MASS TRANSFER.

  • Andreea Andoni asked a question in Separation Techniques:
    Production water slightly blak in colour and and black deposit on inside injection wells?

    I work in oil industry as Field Engineer. Recently I was in the field (a gathering park) to collect a production water sample to conduct a residual oil determination because the water that is separated in the oil-water separation process is the re-injected into injection wells. When collecting the sample from the outlet line of the injection pumps (used to pump the water to the injection wells) I have noticed that the water sample was slightly black in color and after hours changed the color to yellowish / turbid water.

    Also they had a workover intervention to one injection well (into which is pumped the separated production water) and I observed on the inside of the tubing a deposition layer black in color. This deposit is not so hard (like scale), but is a mixture of soft –slimy material and parts which were slightly more harden. After I kept this deposit sample inside of a container (glass and with a lid) I have observed that it started to change color into rust iron color.  

    Could anyone advise what is happening? Could this black color of water indicate the SRB bacteria contamination? The black deposit from the inside tubing of production well could be iron sulfide, biomass? Could anyone suggest some field test to conduct on the deposit sample to identify what is the nature of it?

  • Rakesh Kumar Meghwanshi added an answer in Biosurfactants:
    Can any one help me with a protocol to estimate biosurfactant using a c18 column using HPLC?

    I need a protocol to estimate biosurfactant using a c18 column using HPLC

    Rakesh Kumar Meghwanshi · JECRC University

    Dear Sam Joy.

    first you need to remove proteins from your Biosurfactant Samples. Because proteins can damage columns of HPLC. so first, please find a suitable procedure for removal of proteins from samples. after that you can do HPLC in C-18 or any other column.

  • Vivek Arora added an answer in Chemical Engineering:
    RTD and mixing in plug flow or in continuous reactor?

    Hi all,

    This is going to be a purely chemical engineering thing.

    We know that in ideal reactor, space time (Holding time) is the tideal=Volume of reactor/Volumetric flow rate. But real reactor never behaves like ideal reactor. There are dead zones, channeling in the real reactor, which gives rise to the RTD.
    when there is no dispersion, dead zones or stirring in the medium, mean residence time (tmean)is equal to the Ideal residence time.Stirring or dispersion in the medium is required for good mixing among the reactants by back mixing as well as removing dead zones. That means  

    My question is that will dispersion or mixing increase the mean residence time than ideal case?

    Does better mixing means the lower spread (low variance) of the RTD distribution?

    Is main aim of stirrer in the CSTR to decrease the variance of RTD or decrease tmean or both?

    Please look at this carefully.

    Experts comments are most welcome.



    Vivek Arora · Indian Institute of Technology Madras

    Initially there was a liquid and we know the velocity profile and then start the tracer injection and maintain a tracer mass fraction of 1 at the inlet.

    My question is why the real residence time cant be greater than residence time in ideal reactor? Can you please explain?

    I believe the residence time can be greater than the residence time in ideal reactor



  • Manuel Morales added an answer in Theoretical Physics:
    Is the concept of field the proper way to describe physical processes?

    What is a field? Everywhere around a 'source' of the field, if we put a 'test particle', then a 'force' will be applied to it, coming from the source.
    This definition has a critical drawback:

    • if you calculate, using volume integrals, the total energy of the field , then you will find it infinite. Is this acceptable?

    On the contrary, there exists the interaction from a distance view, where a force is applied to the test particle only when it is being present in the neighborhood of the source. So, we have not any kind of infinite energy here.
    Which approach do you believe that is correct and why? 

    Manuel Morales · TemptDestiny.com - Prephysics Research

    "All words in RG is semantics by definition, Manuel."

    So why have you not conducted the FS thought experiment in real life? After all, since "All words in RG" are just semantics as you stated, you have nothing to worry about. Or are you making another joke?

  • Carrie Ward added an answer in Flip Teaching:
    Has anyone used the Flipped classroom method for information literacy or digital literacy within academic librarianship ?

    I am interested in knowing if anyone has applied or has come across any articles using this approach for information literacy or digital literacy sessions. It would be particularly interesting to know if the examples used other materials other than video or screencasts. I am interested in knowing about the advantages as well as disadvantages as I am thinking of applying the technique in a new post in an academic library.

    Thank Carrie

    Carrie Ward · Aberystwyth University

    Learner engagement  in learning cetainly is crucial, if you can get students offering peer support that certainly seems extremely helpful. 

    Any tips welcome from anyone else interested in this topic on flipped or otherwise learner engagement?


  • Vito S Hernandez added an answer in In Vivo Electrophysiology:
    What is the advantage of using BDA instead of Neurobiotin?

    can some body can help me to figure out the advantage/disadvantages of using BDA vs neurobiotin for in vivo extracellular single unit and LFP recordings and posterior juxtacellular labeling? 

    Vito S Hernandez · Universidad Nacional Autónoma de México

    Thanks, Michel

    I recently received a comment on the subject, it seem that some people that regularly do Juxtacellular labelling in vivo, have found that it is easier to succed in labelling  if they use NB instead of BDA. as i can see, the  only advantage is that BDA have a longer half life.

  • Abu Nurullah added an answer in Forest:
    How the forest ecosystem related to climate change?

    Forest are the main source of the earth which support to protect biosphere. How the climate change effects the natural forest ecosystem and how can we predict impacts and mitigate those impacts? 

    Abu Nurullah · Washington Department of Natural Resources

    You can look at the Wikipedia under the forest and climate change search option. In order to predict the possible impact, there are a number of models such as IBIS, MC1 and a few others. Mitigation issue is specific to the context of the forests in question and the social conditions of the society.

  • Camille Dickson-Deane added an answer in Virtual Learning Environments:
    Are MOOCs a learning method?

    Several times I have found some colleague referring MOOC as learning methods (may be complex, but methods).

    Could they be considered as methods? Or more correctly, they are a class of virtual learning environments, where specific characteristics, like some kind of openness, and a great quantity of students (and, possibly, teachers and tutors), define process and relations among them, which include, specific for MOOC, methods

    Camille Dickson-Deane · Montgomery County Community College

    MOOCs are definitely a design method for the delivery of specific content to large numbers of participants.  I guess the slip of the tongue, one is stating that the design translates into learning - hence the possible description of it being a learning method.  So to use external resources to influence thought the following definition taken from http://www.cipd.co.uk/hr-resources/factsheets/learning-methods.aspx, seems to suggest that Rey's colleagues may be on to something.  The definition from the website states:

    What are learning methods? - Learning methods may be defined as any interventions that are deliberately undertaken to assist the process of learning at individual, team or organisational level.

    So if we use this definition a MOOC (an intervention used to assist the process of learning) can be a learning method.

    I never thought of it as such but its a good question we should really think about..especially when we need to conduct research and sometimes we tend to haphazardly use jargon in our descriptors and explanations.

  • Michel V. Garey added an answer in Inner ear:
    Doing tests on adaptive aspects of frogs. I need document the inner ear histology of frogs.Any have info about microscopy and graphics information?

    histological sources

    Do you have  data for that? 

    Michel V. Garey · Universidade Federal da Integração Latino-Americana

    I do not know many references about inner ear. But, here are some references that can help you:

    Wever, Ernest Glen. "The ear and hearing in the frog, Rana pipiens." Journal of morphology 141.4 (1973): 461-477.

    Lewis, E. R., Baird, R. A., Leverenz, E. L., & Koyama, H. (1982). Inner ear: dye injection reveals peripheral origins of specific sensitivities. Science, 215(4540), 1641-1643.

    Purgue, A. P., & Narins, P. M. (2000). Mechanics of the inner ear of the bullfrog (Rana catesbeiana): the contact membranes and the periotic canal. Journal of Comparative Physiology A, 186(5), 481-488.

    In addition to these bibliographies, I can consult the Wells book (The ecology and behavior of amphibians), specifically the session "anatomy and function of inner ear".

    Best regards

  • Sebastian Block added an answer in Plant Community Ecology:
    How to calculate Jaccard index of similarity between two plant communities?

    I can see contrasting formulas. Sj=C/(A+B-C) and Sj = C/(A+B+C) where A is the species number of community 1; B is the species number of community 2 and C the number of shared species between communities 1 and 2.

    Which one is correct?

    Sebastian Block · Christian-Albrechts-Universität zu Kiel

    Dear Badabate, 

    The first formula you mention, Sj=C/(A+B-C), is correct.

    The Jaccard index is simply the proportion of species of total species pool that are shared by the two communities. Thus, the denominator has to be the total number of species in the two communities combined, and to get that number you should add the number of species in each community (A + B), and then subtract the number of shared species (C). Otherwise, you would be counting the shared species twice. 

  • Abdelhalim Zekry added an answer in Communication Systems:
    For ASK and APSK modulation techniques how can the reciever distinguish between different amplitutes ?

    On ASK (Amplitude Shift Keying) or APSK (Amplitude and Phase Shift Keying) how is it possible to map the different symbol amplitudes into the constelation considering that the signal is attenuated at the reciever ?

    Abdelhalim Zekry · Ain Shams University

    Not at all Jorcy.

    Normally one uses two filters one for equalization and the other for  noise minimization called matched filters.As base band filters, the signal is converted to digital form by a suitable analog to digital converter and the equalizer is and the matched filters are implemented in a digital form. In the advanced radio technology, you can find software defined radio platforms having programmable devices such as DSP processor and field program able gate arrays. However for simple transceivers one can use analog and mixed hardware circuits.

    Best wisshes

  • Maria da Graça Salomão added an answer in Bothrops:
    Where can I found information on clinical syndrome induced by Bothrops marajoensis snakebite?

    A limited number of information exists relative to venom of Bothrops marajoensis. As far as I can see there is none information on the clinical syndrome caused by B. marajoensis accidents in victims. Also, I did not find epidemiological data about the species. Who can help?.

    Maria da Graça Salomão · Instituto Butantan

    Hi Alice, 

    Dr Fan Hui Wen from Instituto Butantan studies snakebite in Brazil and has experience in the Amazonian region. The address is: fan.hui@butantan.gov.br .

    Best wishes,


  • Lucas Marostica added an answer in WNT:
    How do I combination studies of wnt inhibitors with chemo drugs by MTT assay ?

    I want to do combination studies of various wnt inhibitors with chemotherapeutic drugs. I have calculated their IC50 values by MTT assay. Now i am confused how to design combinations.  I am thinking to add fixed dose (IC50) of inhibitor to various doses of chemotherapeutic drugs. can anyone help me in regarding this?

    Lucas Marostica · Federal University of Santa Catarina

    You can use the model established by Chou Talalay(2006). I used this model in my experiments. With this model, you can use data obtained with MTT assay. Calcusyn and Compusyn were the software used. For experimental design, you must first know the IC50 of each individual treatment. After, you should perform the treatments individually and combined at the follow concentrations: 4, 2, 1, 0.5, 0:25 and 0.125X the IC50 value of the treatments, combined and individually. 

  • Michelle Wu added an answer in 5' RACE:
    Does any one have experience with 5'-RACE kit with Genomic DNA instead of total RNA?

    At present I am optimizing the right condition for use of RACE kit with Genomic DNA ? Does any one have any experience , as the kit referred to application of total RNA.

    Michelle Wu · Enzymax LLC

    mRNA Decapping enzymes and Tabasco decapping enzymes are available to replace the TAP used in 5'RACE.  Here is the link for details:


    Here is one of the feedbacks from UmassMed: 

    I used the Tabacco decapping enzyme (cat#87) for 5' RACE and it worked extremely well. 

    I have passed your contact information to other people at UmassMed who use decapping enzymes in their protocols. Please tell people to contact me if they need a good word on this product.

  • Yang Yen added an answer in Fungal Genes:
    Has anyone found an increase in gene expression using siRNA for RNA interference?

    I've targeted siRNA to certain fungal genes, but I find an increase in gene expression for certain siRNAs instead of a decrease when I treat the fungus.  Has anyone else found similar results?

    Yang Yen · South Dakota State University


    We are also working on F.g. We have made a dcl2- mutant and Tri5 in this mutant is completely shut down while other Tri genes are significantly knocked down as well. Clearly siRNAs positively regulate the DON biosynthesis.

  • Vito S Hernandez added an answer in Antibody Generation:
    Inquire about blocking non specific sites in IHC?

    I work with rats doing many immunohistochemical reactions, I have seen that instead of using BSA as blocking reagent, sometimes is recomended that we use the serum of the animal in which the secondary antibody was produced. However wouldn´t be easier if we used a secondary antibody that was produced in rat (in case you use rat tissue) against the species where aur primary antibody was generated?

    Vito S Hernandez · Universidad Nacional Autónoma de México

    Thanks to all, for your answers, I see that the serum made in the host where the secondary AB is produced will bind to sticky sites that could potentially be occupied by the primary antibody. That make sense. I suppose that non immune serum is serum without the Ig fraction? it seems a nice suggestion from Neil, i will try in a reaction against GABA in which I have a low signal/noise ratio. Astrid !!! nice to see you here, how are you doing? I suppose that for the majority of reactions it will be fine with SFB or BSA.

  • Gregory M. Cohn added an answer in Tree Physiology:
    Is there a software to plot the 3D structure of a tree that allows us to perform measures directly on the digital model?

    I need a software to generate a digintal models of trees, this models may be able to be measure and manipulate by the same program. Also it will be nice to know about a software that peforms cuantitative comaprisons of trees topology. Thank you

    Gregory M. Cohn · US Forest Service

    Take a look at CAPSIS-Fuel Manager.

  • Thanaphong Joe Phongpreecha added an answer in Catalyst Preparation:
    Does anyone have reliable resources on practical aspect of catalyst preparation?

    Does anyone have reliable resources on practical aspects of catalyst preparation, especially activation step in H2.

    Some questions I have is, is it safe to reduce catalyst in pure H2 gas? including the effect of time length and temperature during reduction.

    Thank you.

    Thanaphong Joe Phongpreecha · Michigan State University

    @Neus Blanch Raga - Thank you, that's what I plan to do too (moving everything to the glove box) because the solid is a fine powder and it sticks on the wall. The only way is to open up the reactor and add it.

    @Thomas Hanh - Yes my catalyst would be contact to gas phase (no liquid). Basically what I have in mind is that I will reduce cat. in Parr reactor. Once done, then move to glove box, open it, and add solid and solvent. My concern is that the reduction step is not done in open system. Do you have any knowledge of that? Thank you.

  • Michelle Wu added an answer in RNA:
    Advice on 5' RACE without a kit?
    Does anyone have advice for doing 5' RACE without a kit? I have been using the Ambion Firstchoice RACE kit to compare capped RNA in Arabidopsis mutants, and it works well but is super expensive so I would like to try to do it without a kit. So far I see the TAP is the most pricey part of the kit. But I am reluctant to do it a different way since so far it has been working and I don't want to waste lots of time....Any advice will help!
    Michelle Wu · Enzymax LLC

    mRNA Decapping enzymes and Tabasco decapping enzymes are available to replace the TAP used in 5'RACE.  Here is the link for details:


    Here is one of the feedbacks from UmassMed: 

    I used the Tabacco decapping enzyme (cat#87) for 5' RACE and it worked extremely well. 

    I have passed your contact information to other people at UmassMed who use decapping enzymes in their protocols. Please tell people to contact me if they need a good word on this product.

  • Hamid R. Jamali added an answer in Basic Statistical Methods:
    How do I test a relationship between participants level of education and responses to a likert scale question?

    I am trying to test the hypotheses which says that those with higher education will not choose vocational education as a first option for their children, while those without higher education will choose vocational education as a first choice for their children?

    • dear researchers, I am struggling with statistical testing at the moment. How do I calculate if there is a statistical relationship between participant responses to two likert scale question? what is the best test to use if I want to calculate the relationship between respondents level of education (coded from 1-9) and their response to a likert scale ( 1-5) question? I also want to find out if their is a relationship between respondents income and their response to a likert scale question. I have divided the educational gruop into those who have completed higher education and those who have not attained or completed higher education. I am trying to find out if there is a difference in the responses of those with higher education and those without higher education. same thing applies to those who earn lower wages and those who earn higher wages. higher 
    Hamid R. Jamali · Kharazmi University

    Seems your independent variable (education) has two groups (2 independent groups) which are those with and those without higher education. Your test variable is likert and although some people would say it is wrong to do, you can find a lot of studies that use likert scale data for parametric tests. So you might also run a '2 independent samples t test' and see if you find any difference between two groups or run an equivalent non parametric test (Mann-Whitney test).