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  • Francois Valade added an answer in Ascomycota:
    Literature about Verpa or Ptychoverpa?

    Could anyone recommend me any research articles concerning morphology and life cycle of species of genus Verpa or Ptychoverpa?

  • Malik OEDIN added an answer in Environmental Monitoring:
    It is necessary to replicate fly out count of flying-foxes ? 1, 2 or 3 day counts, what is better ?

    I'm working on Flying-foxes monitoring and I want to know how I can built my protocol of fly-out count.

    Malik OEDIN

    Thanks for your answers.

    Yes, weather might inflence the number of bats leaving the nest and the precision of the observer count.

    I want to know if it's necessary to make many days of counts (3 days or 2 days for example) to obtein a good precision of count or if one count is sufficient ?

    Flying-foxes seems to be very mobile species and their abundance in the colony may vary day to day so I don't know what is the better choice between the two options.



  • Walter J Flapper added an answer in Cleft Lip and Palate:
    When should we first refer a CLAP to a "CLEFT TEAM" for evaluation and management?

    1. CLAP- Cleft Lip And Palate

    2. Any specific age in days/months/years

    Walter J Flapper

    These patients should be referred as soon as the diagnosis is made. In many cases, this is now at the 20 week ultrasound scan. An early referral to the cleft team at this stage allows appropriate counselling of the parent(s) regarding teh management protocol for their child. At birth, early intervention by the speech pathologist can help optimise the feeding of the baby prior to the lip repair.

  • Debra Sharon Ferdinand added an answer in Reading:
    What supports are needed to be in place to offer effective reading instruction in both learning to read, and read to learn?

    This could in all content area math included.

    Debra Sharon Ferdinand


    Ensure the reading material relates to students' prior readings, experiences/interests, or societal issues to make it interesting and motivating for them, especially at the primary level. They would be able to relate to this material much easier. 


  • John Beiswenger asked a question in Connectivity:
    Are you reasearching the causes for Autistic Savant abilities?

    I am interested in connecting with anyone who is researching the causes for the remarkable abilities of autistic savants.

  • Zeljko Krneta added an answer in Repeated Measures:
    How are the variables adjusted in repeated measurement test?

    How do adjusted variables in repeated measurement test?

    Zeljko Krneta

    Hamid, You can do it in the SPSS with RM. You have 3 levels of measurement and a number of factors. Thus, in the input field of factors in the RM analysis, enter  your basic dependent variable, which defines the control and experimental group, and gender variable also. In this way, you test the total change in time over the multivariate analysis (main effect of time), then the overall difference between the groups, and  interaction of these two factors (time-groups) but also differences between the sexes and the interaction of all factors (time-group-sex). The analysis is not simple. Look for examples on the internet to be able to interpret your results. Greetings and good luck

  • Rafael Bello-Bedoy added an answer in Population Genetics:
    Can different partitions for regions produce different Percentages of Molecular Variance values at Within Pops level for the same populations?

    Can different partitions for regions produce different Percentages of Molecular Variance values at Within Pops level for the same populations/samples data? Thanks

    Rafael Bello-Bedoy

    Hi Alex, everytime you change the structure of the population, you will have different values because the within groups variace changes too. But it seems that your comparisson between gruops is giving the same values, even when you are changing the number of populations. I would expect it to change too, since between populations values depend on the population's structure,  

  • Ahmad Fazeli added an answer in Protein Elution:
    How can I purify a recombinant protein without urea and salt?

    I had produced and purified the recombinant protein by genetic engineering. However, the protein was eluted from resin with high salt and urea solution. When I use dialysis method to remove them, the proteins aggregated.  When using ultrafiltration, the protein did not accumulate in upper solution. I just want the protein in low salt solutin but with high concentration.

    Ahmad Fazeli

    There are several nonioni surfactant e.g. Polysorbates, and, plutonics which you can use during your buffer exchange dialysis/UF process. 

  • Refik Kanjhan added an answer in Immunofluorescence Staining:
    Which is the best cost-effective mounting medium for Immunofluoresecnce?

    Dear fellow researchers,

    I am looking for some cost-effective suggestions for the mounting medium. We have used the one from Thermo-Fischer Scientific until now and it has been working "OK" till now. However, I have read some articles in which researchers have pointed out the benefit of using the best mounting medium to stop the photo-bleaching for a longer time. Therefore, we have decided to try some other options this time which are more cost effective.

    Any kind of suggestions for cost-effective mounting mediums are highly appreciated.

    Thanks in advance.


    Refik Kanjhan

    Dear Udesh,

    If you cant get any of those listed above you can also use just glycerol or if you are worried about pH than make your own glycerol-carbonate (pH 7.4). See my thesis for details.

    best wishes,


  • Marek Olejniczak added an answer in Euthanasia:
    Physician-assisted suicide: should it be proposed or opposed?
    Physician-assisted suicide: should it be permitted or not?
    Marek Olejniczak

    It depends on how you understand the term "physician". If you think that this is someone who heals and saves lives, the answer to the question is obvious. In my opinion physician-assited suicide should be always prohibited.

  • Silvino Martins added an answer in Mobile Applications:
    What is your experience when using cross-platform tools for developing mobile applications mainly the drawbacks of each one?

    I would like to know your experience when using cross-platform tools for developing mobile applications. What is your experience mainly the possibilities and drawbacks of each one?

    Silvino Martins

    As mentioned, Phonegap it's a very good choice if you have a web based application (based in a web page for instance) and want to make it hybrid. Of course you won't have the same performance as if you had it developed in a native language but it's a good of way to save resources in case you already have a web application developed or have no skills in native programming.

    Xamarin I've never heard of but it seems similar to Libdgx in the way that you need to program only once (natively, in the language you want) and it's possible to export to every platform. I've never used it (Libdgx) but I was part of a project where the developer choosed it because the fact it is cross-plataform and very well optimized for performance issues (also, it has a good community of developers with certified knowledge who maintain and upgrade the code very often).

  • Javier Armando Baron-Miranda asked a question in IP:
    Which it is the ecuation for calculating the polydispersity index using Dynamic Light Scattering?

    I do not understand why the smaller nanoparticles have the largest IP (even 0.7) and have not found an equation that satisfies the values of IP that gives the Zetasizer equipment.

  • Michael Schmitt added an answer in Silica:
    How can I wash silica particles that are made by the stober process?

    I have some problems  about washing silica particle that are made stober process. 

    For washing, i just add ethanol and water. Then, I centrifuge mixture ( 13000rpm, 15min)

    However, I found that precipitate is like a gel. In SEM images look like the smooth board. 

    Is it normally phenomenon?  Or Am i missing step? 

    Michael Schmitt

    Stober synthesis using e.g. TEOS in EtOH and NH3aq leads to a highly reactive reaction mixture which leads to charge stabilised silica particles (every monomer is consumed) . Some interesting reference may be found in the reference. Adding additional silane to the mixture allows to grow or surface modify the particles. My guess is that the centrifugal forces in combination with the reduction of the stabilisation by decreasing the pH allows the still reactive silanol groups of you surface to react with each other. Dialysis works very well to transfer the particles in e.g. Ultra pure water ( if you are interested in self organisation) or after modifications in EtOH.

    if you want to use the centrifuge modify the particles directly after the synthesis simply by adding a small amount of mono-organyl trialkoxy silane.

    A spectroscopic study may help to analyse your particles.

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: The consecutive reactions of acid involved siloxane formation are firstly measured in bulk and analysed by Raman spectroscopy. Influencing factors, which can be identified as the chemical properties of the silanes, the silylium cations, and miscibility are pointed out by using a special technique. The procedure is based on a modified Raman sample cell, which allows a single-phase system with controlled water content to be systematically quantitatively monitored. Additional to the novel opportunity to analyse the acid “catalysed” condensation during the formation of polysiloxanes, this publication contains an alternated theoretical mechanism for sol-gel synthesis considering a restricted water content. A major aspect of this introducing study is a detailed analysis and identification of the relevant Raman vibrational bands and their origin on the hand of ten different organyltrialkoxysilanes (methoxy and ethoxy). The ability to determine the kinetics of the acid catalysed formation is demonstrated on homologous series of alkyltrimethoxysilanes.
      RSC Advances 01/2014; 4(4):1907. DOI:10.1039/c3ra45306e
  • Chris B Allen added an answer in Vascular Biology:
    What computer program should I use to compare plant communities?

    I'm doing an inventory of vascular plants in a piedmont gorge (USA) and I'm going to do some transects for community comparisons and analysis. I'll compare communities on different facing slopes and of different elevations. I hear R is the go-to program but are there any other tools I should consider?

    Chris B Allen

    I agree that R is a very diverse tool and can be used for free, which is certainly a bonus, but be aware that the learning curve for R is steep and the enormity of its capabilities can be overwhelming. Once you know R it is brilliant. A good package for community work is PRIMER 6 (plus Permanova). This you would have to pay for once, but it is far more intuitive and specifically designed for the multivariate analyses you will need. Citing its use may also be easier. If cost is not your issue I would use Primer, I have used both for plant communities of NSW Australia

  • Kenneth S. Bigel added an answer in Ethics:
    Should ethics be taught to undergraduate students?
    Ethical principles as a special subject is taught to all graduate students. Typical coverage in our curriculum is as follows:

    Survey of the issues, values, principles, and ethics of a technological society. Emphasis on the leadership principles, behaviors, and normative ethics of the technologist to practice the ethical decision-making process within a technological or institutional organization.

    However at undergraduate level it is not included. What is your opinion? Should ethics be taught at undergraduate level? If yes what could form part of the coverage? If not can you explain the reasons for the same?
    Kenneth S. Bigel

    Of course it should!  My own research has shown that teaching ethics has a positive impact on undergraduates' ethical development as measured by James Rests's Defining Issues Test.

  • Rafik Karaman added an answer in Halogens:
    Can I replace silver for abstracting halogens from alkyl halides?


    i'm trying to generate an mild carbon cation  from alkyl halides for certain reaction with silver salt. the problem is with the cost and conditions of reactions (temperature below zero are only suiting). suggest me with cheaper replacement for the silver. or at least a reference where the reaction is done between -10 to 0 degrees. i would be grateful. 

    Rafik Karaman

    Dear Michael,

    I agree with you that the question is not clear. It might be due to the fact that the person does not write or write fluent English.

    My answer on Grignard was pointed to Benjamin who responded to Sameer's question.

    Since I am an Arab I can understand the English of Arabs. It might be difficult for you to understand the English of Arabs since you are NOT an Arab.

    Hoping that I clarified the point,


  • Malik OEDIN added an answer in Teeth:
    Any suggestions about the determination of the age of flying-foxes ?

    I have seen that determination of age by teeth analysis is possible ...

    Malik OEDIN

    Hi, thanks for your answer.I think it will be usefull for my study. I've also found two publication about age determination by microscope analysis of cut sections of teeth.



  • Muhammad Khattab added an answer in Spectroscopy:
    What does large stokes shift mean ?

    The compound under study exhibits large stokes shift in polar and nonpolar solvents ranging from 90:170 nm. what are all rationale for this large shift?


    - excited state intramolecular hydrogen transfer

    - aggregates

    - exciplex

    ....... etc

    Muhammad Khattab

    Thanks all!

  • Muhammad Khattab added an answer in UV-Visible Spectroscopy:
    3D excitation, emission and excitation-emission experiments?

    I am wondering what is the importance and how to interpret these experiments. Also, i noticed that i can't have background corrected (No blank subtraction) for these experiments using perkin elmer equipment. How to solve this problem?!!!! Besides, I appreciate if you could send me some resources to read about 3D experiments.

    Thanks in advance, 


    Muhammad Khattab

    I mean 3D technique for plotting excitation, emission and intensity in contour or colored map.

  • Jacinto Elias Sedeño Diaz asked a question in Demand:
    How can you explain very high COD values as compared with BOD in saline lakes?

    In some water bodies of Central México with solonchak soil type, We have been recorded high values of chemical oxygen demand in a rate of several times the values of biochemistry oxygen demand.

  • Darren Peters added an answer in Sport Psychology:
    What are the most common tests to measure the motivation for sport in disability?

    I think that  I could use:

    • Physical Activity and Disability Survey (PADS) (Rimmer et al., 1999)
    • BREQ-2 (Markland & Tobbin, 2004)

    Do you Know a better test?

    Darren Peters

    Hi I would either use the Motivation and Engagement Scale by Martin (2007) or the Motivation scale by Vallerand et al. You could look these up. Each has a differing conceptual basis. In my mind as a former CEO of Paralympic Sport, and depending on your research question, you should measure this in the right way depending upon the 'context' e.g., an athlete enquiry, a person with disability and their involvement enquiry, an organisational enquiry etc.     

  • Jerry Rhee added an answer in Complex Systems:
    What is the minimum number of components in a complex system?

    Complex systems consist of multiple interacting components. Two components is not enough to make a system complex. But would three or four components be enough for a system to become complex? What would be an example of such a system? 

    Jerry Rhee

    Also, here are some examples that would appeal to humanists for why three and not two:





  • Motasem Saidan added an answer in Environmental Engineering:
    How can the environmental pollution caused by plastic be controlled?
    How can the enviromental pollution caused by plastic be controlled?I heared that phthalate compounds plays a major role.Show some research articles?​_

    How can the environmental pollution caused by plastic be controlled?I heared that phthalate compounds plays a major role.Show some research articles?

    Motasem Saidan

    By imposing  levy on the plastic product, and consequently the competitive market will take the lead. The levi amount depend son the plastic externality= environmental damage cost

  • Paul Wytch added an answer in SPSS:
    How can I improve a multiple regression model?

    I am using 10 IVs to design a model for a DV.

    I have initially used the Enter method on SPSS (all ten IVs have been put into the model) and I have an R square value of .65

    I really want to try and improve the correlation coefficient and am considering using a hierarchical method and leave out IVs that do not significantly correlate. 

    I am not sure whether to add the remaining IVs one at a time, in order of their strength of correlation to the first model or quite how to go about doing this.

    I can find lots of texts on how to mechanically conduct the hierarchical model but nothing on the reasoning I should be considering when taking out IVs and putting others in.

    Any advice or direction to the relevant texts would be appreciated.

    Paul Wytch

    Thank you to everyone for your insightful and helpful replies. I have received a lot of useful information from your responses. 

  • Jette Mebrouk added an answer in Critical Care Nursing:
    In a 8 hour shift basis, what is the usual schedule? How the week is distributed between working and free days?

    I`m a critical care nurse from Chile and we work on a basis of 12 hours shifts called "4ª turno" (fourth shift) which means a 4 day rotation starting with a day shift (8:00 am to 20:00 pm), second day night shift (20:00 pm to 08:00 am of the next day), third day and fourth day are free.

    I would like how works the 8 hours shifts because some hospitals in my country are trying to change to this kind of work.

    Jette Mebrouk

    Hi Madelaine

    I cannot see any link or title of the article you referred to. Please resend.