Q&A

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  • Can someone kindly highlight a research article addressing the issue of employee engagement in decision making?

    There are many generalized research papers, outlining the impact of certain variables on employee engagement or work engagement. Is there any research that specifically highlight that employee engagement in the company decision making is an issue and further addresses it through some variables impacting on it. 

    Chux Gervase Iwu · Cape Peninsula University of Technology

    hi check if this article 'Employee participation and productivity in a South African university. Implications for human resource management' will assist. 

  • What would be the preferable method to administer oral dosage form to patients having swallowing difficulties?

    Depending on the Tab or Cap, and the type of medicine, modifying these dosage forms can lead to reduced effectiveness of the medication, and increased risk of adverse effects. especially in hospitalized patients. Any alternative method then?

    Hina Hussain · lahore medical and dental college

    Can you plz mention here which drug you want to administer and its not possible ? than it will be more easy to answer your question. 

  • Samuel Ankamah added an answer in Decentralization:
    Any strategies to improve participation and accountability through decentralization?

    Best ways to promote participation and accountability through decentralization

    Samuel Ankamah · Griffith University

    I believe strongly that the whole idea of decentralization is to improve local service delivery for the quality of life for the local people. This has increased local government discretion leading to local corruption making the poor to suffer the consequences. The whole concept of participation and accountability is to reduce corruption to improve the quality of life of the people since corruption cannot be completely eradicate, so some scholars including the world bank claim. To reduce it therefore, I would recommend the application of Klitgaard's formula ( inversely I mean); Corruption=Monopoly+Discretion-Accountability. Again the concepts of Societal/social accountability and that of Goetz and Jenkins " diagonal accountability. Hope it helps

  • Rajesh Arumugam added an answer in PCR:
    How can I get rid of the faint smear in PCR?

    Hi all,

    My PCR products always show a very faint smear spreading all the way long (from the wells to the band of interest). I´m not being able to get rid of it. I have the same problem with two different PCR reactions. I've checked the DNA quality by running it in an agarose gel 0.8%. It looks fine.

    I've tried:

    - Reducing the DNA amount: Then the intensity of the amplicon of interest decreases, the smear is reduced but is still present.

    - Reducing the number of PCR cycles: Same (the intensity of the amplicon of interest decreases, the smear is reduced but is still present)

    - Higher annealing Ts: The smear remains.

    I'm using a NOT HotStart Taq Polymerase (Kappa). Do you think that using a different type of polymerase can make the difference?

    Any other suggestions?

    Thanks in advance

    Rajesh Arumugam · Christian Medical College Vellore

    Hi,

    The main reason for the smeared band is as follows

    1. High Salt concentration in sample(Please standardize the Mgcl2 conc in PCR mix)

    2. DNA degradation by Nucleases( Please use the Proper Nuclease free Water in the PCR MIX)

    3. Improper electrophoresis condition( Please check the Gel tanks and the power cards for the salt formation)

    4. Poorly formed gel

  • Manmohit Kalia added an answer in Quorum Sensing:
    Problem in dissolving AHL (3oC12HSL)
    I am trying to make a working concentration of 500 uM 3oC12HSL in LB (or any other aqueous medium for bacterial growth) by diluting my stock solution of 100 mM 3oC12HSL in DMF. Every time I add my stock solution to the medium the AHL starts to precipitate. I understand it is sparingly soluble in water. Is there any way to dissolve AHL into aqueous medium?
    Manmohit Kalia · Motilal Nehru National Institute of Technology

    I also faced same problem , as per the instructions of the manufacturers i dissolved it in DMSO, but DMSO affected bacterial growth. I asked Dr. Greenberg he told me to go with the Acidified ethyl acetate 

  • Does 260/230 ratio matter when it comes to sending samples for sequencing?

    I am trying to extract RNA from a non-model organism (Malvaceae) for transcriptome sequencing. I have used Nucleospin Plant RNA kit (MN) together with Fruit-mate (TaKaRa), because of probable high contents of polyphenols and polysaccharides.

    However, I still have problem getting the 260/230 ratio up to >1,9 using these protocols. Have anyone used this?

    • Adding the homogenized sample to the RA1 or RAP turns everything to glue, that I either have to cut to release from filter-tip.
    • Using fruit-mate turns the material black and the precipitate is still kind of thick. How does your samples react?

    Best regards,

    Jonna E.

    Jonna Eriksson · University of Gothenburg

    Thank you all for the replies. I have sent emails to the company that will do the sequencing for us about the polysaccharides etc. We will probably use illumina MySeq for a de novo assembly.

    I believe that the CTAB method should do the trick on my specimen. I just did not want to use it if there was alternative kits. 

    Thank you again!

  • How do we decide which machine learning algorithm to use for a specified problem?

    Every machine learning algorithm has its advantages and disadvantages over other algorithms. Now, if we are asked to use an algorithm for classification then how do we decide whether we should go for SVM, GMM, or any other topic modelling technique?

    Constantin Ungureanu · Technische Universiteit Eindhoven

     A small amendment on Luca Parisi comment.  I agree with you that my proposed method it can be affected by bias. And I strongly believe that there is no ML which can work perfect on any data. in the literature almost every person has their own  preference based on objective or subjective reasons. I suggested to Muhammad to start with something and then he can decide if he needs other ML or not. Moreover, if the feature selection is not done properly this will affect also the performace of the classifier. Regarding the comment on speed I stand by it. In my work I am developing classifiers for real time processing,  in this case the speed of training and classification needs to be virtual zero. in the end, it depends on what data you process.

    to resume: what I found that it works (at least in my case  with physiological signals) is a ML based on physiology combined with decision trees. good luck and thank you Luca for your comments

  • Ronán Michael Conroy added an answer in T-Test:
    How do you split a numeric variable in stata?

    I have a variable for Diabetes. For each diabetic AND nondiabetic, I want to know if they have high blood pressure or not. Currently, I have this in a table. After this, I have diabetics with and without high blood pressure, I want to have some sort of indicator variable that they fit this category. So, I can use this for my analysis. 

    Eventually, I want to use a t-test or fischers exact test on this data. 

    Ronán Michael Conroy · Royal College of Surgeons in Ireland

    So you have two explanatory variables (I think – correct me if I'm wrong) : you have

    - diabetes (0/1)

    - hypertension (0/1)

    What is not clear is what you're going to do a t-test on, since t-tests apply to continuous data. 

    I have a sense that you want to see if the presence of hypertension changes the effect of diabetes. If this is so, then you need to look for an interaction effect. Suppose you wanted to look at their interaction in predicting levels of albumen. Your model would be

    . regress albumen diabetes##hypertension

    This will give you an overall effect for each predictor plus an effect where both are present together. If this latter effect is significant, then the two factors interact.

    Is this the sort of thing you're looking for? I'm guessing from the information you gave us.

  • How can I get rid of e-waste?

    Up to 90 percent of the world's electronic waste, worth nearly US $19 billion, is illegally traded or dumped each year, according to a new report.

    • E-waste comprises highly toxic chemicals.
    • Each computer contains numerous such chemicals, including lead, mercury, cadmium, brominated flame retardants (BFRs) and polyvinyl chloride (PVC).
    • These cause cancer, respiratory illness and reproductive problems.
    • Chemicals are especially dangerous because they migrate into the soil, water and air, and accumulate in our bodies.
  • Kim Trollope added an answer in Codon:
    Would a single aa substitution in a protein severely compromize protein expression given that the parent protein is well expressed in the same host?

    The gene was expressed in S. cerevisiae. Site directed mutagenesis study the codon for the amino acid substitution is not a rare codon. Alternately, could anyone send me a paper that has shown that a single amino acid substitution severely compromises protein expression? The vast majority of authors in protein engineering papers claim that abolished enzyme activity is due to the amino acid substitution rather than compromised protein expression. How would this be shown experimentally?

    Kim Trollope · Stellenbosch University

    Hi thanks for all the replies!

    I made a library of protein variants with single amino acid substitutions (different ones) throughout the protein sequence in loop regions.  From screening the enzyme activity i assumed that the substitutions in the non-functional ones abolished enzyme activity.  I focused on the active ones and continued with purification and further characterisation.  However questions have arisen whether function was abolished in the 'non-functional ones' or if their lack of expression is yeast was the reason for lack of detectable activity.  I was wondering if abolished protein production/targeted degradation is a common phenomenon with single amino acid substitutions and would like to see publications on this.  My searches have not yielded any but it is possible that i am not searching effectively.

  • What is the physical meaning of the negative activation energy for the electrical conductivity?

    The electrical conductivity of my sample increases with the temperature, and shows a linear behavior in Arrhenius plot, so when I calculated its activation energy, it turns out to be negative. Does it mean that the charge carriers are much more easier to move in comparison to those with positive activation energy? 

    Kannan Radhakrishnan · Pondicherry Engineering College

    I agree with Dr.A.Kumar, which I have come across in my studies. Increase of conductivity depends upon carriers, mobility. T to the power other than unity leads to different models may localisation-VRH,SPH etc. 

  • Marc Baeta added an answer in Gastropoda:
    Do these shells belong to Trochidae or Calliostomatidae?

    Images of 2 gastropod shells is attached (dorsal and ventral). While one shell had thin, black markings running vertically from the apex to the last whorl the other had thick markings. Shell length is 15 & 18 mm while the width was same (12 mm). Do the shells belong to Trochidae or Calliostomatidae? The characteristic stepped spire is seen and the pointed apex is similar to both these families. I would appreciate if anyone could identify them.

    Marc Baeta · Autonomous University of Barcelona

    It is Trochidae. 100% sure

  • Omid Izadi added an answer in Elastic Modulus:
    How can I determine the elastic constants for cohesive elements?

    Dear all,

    I am modelling bonded interfaces using cohesive elements and trying to define the values of Knn, Kss and Ktt for uncoupled traction separation behaviour.
    My question is that how to determine the values of these terms, i.e. Knn, Kss and Ktt. Can someone please let me know on how to calculate these terms or any other information that relate to finding or working of such terms.

    Many thanks in advance for any kind help

    Omid Izadi · Isfahan University of Technology

    thank you for your reply ,professor Franck Lauro

    I searched in the internet for works of David Morin, But I could not find anything from David Morin, also works of Jean Yves were very much  and I am confused. So, would you help me better and tell me which works of  David Morin and Jean Yves have explained this method?

    Many thanks in advance for any kind help

  • Hopewell Molefe asked a question in Silver Nitrate:
    What would be an alternative of testing for chlorides in the effluent?

    What else can I use apart from titration with expensive silver nitrate and mercury nitrate methods?

    I have to test for chlorides in my effluent, I'm struggling to get silver nitrate solution so far. So I want to know an alternative way to know the concentration of  Cl- in my effluent.

  • Vincent Hahaut added an answer in RNA:
    What is quality RNA ? How one can evaluate this by running Gel Electrophoresis ?

    I have been extracting RNA using TriZol for about a month but not getting good results, can't even understand the problem lies where. Can anyone point out my possible mistakes during this process by analyzing this pic ?

    Vincent Hahaut · University of Liège

    Hello!

    Such low ratio could be signs of contamination by phenol or proteins (http://www.nanodrop.com/Library/T009-NanoDrop%201000-&-NanoDrop%208000-Nucleic-Acid-Purity-Ratios.pdf). Are you sure that when you recover the upper phase you don't go too far and pipet inter- or lower phrase? You really need to do it slowly and let a few millimeter of upper phase. 

    You could try to put your RNA on a RNAeasy Quiagen column and see what you get after. 

  • Nicola La Porta added an answer in Forest Ecology:
    How will soil temperatures inform about forest conditions?

    If I have some rapidly sampled soil temperatures from a few different forest types in one conservation area, how many days' sample will be useful to learn about the conditions for the forest cover type?

  • Florian Goetz added an answer in Nutrients:
    How to isolate extreme acidophile bacterial of acidic water from crater lake?

    I collected soil and water from the crater lake. Location of the sample I took at Ijen Mountain, Banyuwangi, East Java, Indonesia. The water is extremely acid that the pH is + 0-1. I want to identification the acidophile bacterial by 16S rRNA sequencing but I want to try to isolate the bacterial first.

    My method is try to cultivation the sample into Nutrient Broth and/or Nutrient Agar with pH adjustment to 5 to create acid environment on that medium, but no one of them is growth.

    Is there any wrong on my method? Or are there better way to identification the bacterial?

    Florian Goetz · University of Greifswald

    Well I would use a liquid medium with similar composition and pH of your natural sample ( like Bhoj suggested pH below 3 and soil extract). By the composition of iron, sulfur and aluminium  I would choose a medium targeting chemotrophic bacteria. And you will probably need patience as far as I know these bacteria grow slow.

  • Is anyone familiar with innovative research methods to assess social acceptability of technological innovation?

    Dear all,


    We are conducting research on the societal impact of technological innovations. One of the main tasks we are trying to carry out is to assess acceptability of innovative solutions based on technology, that gather data on people and that may arise privacy and other ethical concerns.

    That is not as simple as asking: would you accept a technological solution for X doing that thing?
    In this context, as a researcher how do you assess the perceived benefits and the perceived risks? And how do you foresee the acceptability and the reactions to something they can barely imagine without imposing the problem to your informants?

    We are considering to use quasi-experimental designs, where people will answer freely on a first stage, then will be exposed to a stimulus (a scenario, a role playing, a gamified experience...) and then be asked the same questions again and see the differences between before and after the stimulus. However, this design is highly sensitive to how well the stimilus are designed.

    Any help, reference or hint on that? Any other approaches, rather than quasi-experimental design that could be used in those cases?

    Thank you very much!!

    Elisavet Dimitrokali · The University of Warwick

    Hi Lilliana,

    I would highly suggest participatory approaches using low fidelity and high fidelity activities to explore people's perception on technological innovation. If you are interested to find out more, please contact me by email.

    e.dimitrokali@warwick.ac.uk

    Regards,

    Elisavet

  • Are there any geophysical method for extrapolation underground water?

    Is there any geophysical method that can be used for exploration underground water and can be used for determining chemical properties of water?

    Hebbache Kamel · Université de Biskra

    In order to get suitable results for identifying the depth of water table, For me the ERT technique is good,with short distance between the electrode and choose the optimum electrode array, but for more detail about this you can use the VES. the integration of both technique gives many information for the target of interest. Many scientific papers available that use ERT and VES at the same time.    

     
  • Marina Tišljar added an answer in Canaries:
    Has anyone seen the changes described below in canaries?

    The typical was a rapid spreading among the birds and a great mortality. In most of the birds the feathers in abdominal area were slightly removed. The youngest birds were not affected. The avian pox virus infection was excluded.

    Marina Tišljar · Croatian Veterinary Institute

    Thank you very much for your suggestions. Before the first clinical signs the owner visited one of the european exhibition (I do not know in which town) and he confimred that the illness started to spread after this. The Mycoplasma was negative, but regarding the  fungi and bacteria I can only confirm the positive HP results. Namely, the owner did not want microbiological testing except the virological - on pox virus infection (I think that  some of bacteriological testings were done a day or two before he came in our Centre and that the results were negative /?!?/). 

  • Majid Javanmard added an answer in Ensemble:
    Has anyone worked on usage of Ensemble Methods to reduce Uncertainty of forecasted data !?

    Hello everyone 

    I am going to work on using Ensemble Methods in Machin Learning such as Boosting, Bagging, Random Forest &.... to reduce and analysis of predicted precipitation by Global Weather Models(Ecmwf, Ncep and etc.).

    My first question is about possibility of this opinion , Is it possible at all to use these methods to combine members outputs of models? 

    For second question, can anyone recommend a review article or a book that explained these methods completely !?

    Thanks for your time and consideration in answering my question.

    Majid Javanmard · Tarbiat Modares University

    Thanks for your Attention Mahboobeh Parsapoor, but it would be awesome if  it`s application in Weather Prediciton field is available. 

  • Jan Balvan added an answer in Apoptosis:
    How do I observe the onset or process of apoptosis in live cells?
    I would like to image the cell apoptosis using live cell imaging. Is there any indicator of apoptosis? Drugs or plasmids are both OK.
    Jan Balvan · Masaryk University

    Hi,

     best method is time-lapse hologarphic microscopy

  • How can I disaggregate monoclonal antibodies?

    I have just started to work with monoclonal antibodies and I have found that my mAb forms aggregates. I`ve tried to use a thermal cycling method (heating to 60ª and then rapid cooling to 10ºC, for 2 hours) but I still have aggregates.

    Robert Friedrich · Glycotope

    It will be hard to resolve aggregates to monomers again -> better you try to remove them by SEC (or HIC)

  • Aamir Abbas added an answer in Inductor:
    Relation between peak inductor current and the load current of a buck converter working in discontinuous conduction mode?

    Relation between peak inductor current and the load current of a buck converter working in discontinuous conduction mode?

    Aamir Abbas · National University of Science and Technology

    I(inductor max)=Vo(1/R +(1-D)/2fL) where D is duty cycle, Vo is output voltage. Discontinous or continous mode depends on value of inductor which should be           L>(1-D)R/2f  for continous mode. 

    Whereas load current is Vo/R. 

  • Jan Balvan added an answer in Annexins:
    Can phosphatidylserine be exposed by live cells not undergoing canonical apoptosis?

    Is it possible that cells identified as apoptotic by their viability plus Annexin V binding are actually undergoing a process of cell death or cycle arrest different to canonical apoptosis? For instance, piroptosis, oncosis, or other?

    Jan Balvan · Masaryk University

    Hi Enrique,  

    similarly as apoptotic cells, oncotic cells could exhibit external phosphatidylserine residues (PS) while maintaining membrane integrity

  • Somya Joshi added an answer in E-Government:
    Is there any specific method how we can assess e-government maturity level?

    assessment of e-government maturity level

    Somya Joshi · Stockholm University

    I found this article to be very informative and might help you in your research on e-goverment maturity models:
    https://ict4dblog.wordpress.com/2015/03/23/a-better-e-government-maturity-model/

  • Alain Mercier added an answer in Pedagogic Theory:
    Can you suggest articles about FL lesson planning paradox?

    I HAVE BEEN LOOKING FOR RESEARCH ON LESSON PLANNING PARADOX AND THE WAYS OF DEALING WITH IT DURING FL PRACTICUM. Thank you for your help in advance.

    Alain Mercier · Ecole normale supérieure de Lyon

    For practicum, and lesson planning, a reference from scholar (the third, there are pages and pages)

    http://www.tandfonline.com/doi/abs/10.1080/13598660220135694

    Scholar gives availables references for planning paradox too.

    Hox to deal with this, which is the problem of each teacher: "If you teach in at school, sudents ar not at work but if they are at work what do practicers learn?"There is no answer as the paradox does not exist but for lazy teachers, as Socrates would say (see MENON dialogues. Studying is the answer, at school (during leisure times) and at work (doing tasks is not enough for studying people). The question is now: "How can a teacher drive students to study?" This question has answers from didactics research.

  • Adam Fforde added an answer in National survey:
    Can anyone suggest how to calculate a sample size and sampling design for a national survey?
    We are planning a study to determine thalassemia carrier prevalence in a developing country
    Adam Fforde · Victoria University Melbourne

    Any standard statistical textbook, but if you do not know it would be very risky to agree to do the survey. 

  • Nancy Ahmed asked a question in Complete Blood Counts:
    Which is better EDTA or heparinized tubes for mouse blood to isolate healthy WBC and for ELISA?

    Which is better EDTA or heparinized tubes for mouse blood, I tried EDTA but it causes clotting sometimes although I put 1-2 ml blood only in the tube. And I tried heparin but it caused hemolysis . I need healthy WBC and I will also perform some ELISA parameters and complete blood count. What is the best speed of centrifuge (rpm) that I should use to separate plasma from cells without damage? what is the duration?

  • Raymond Fokom added an answer in Mycorrhiza:
    What do you think about pseudo-absences in ecological studies?

    The objective of my study is to elucidate the relationship between individual species of mycorrhiza and environmental variables using Spearman correlation. I wonder if I should exclude absences records because not detection doesn't mean inexistence of the specie.... I think that this is true but I am not sure if this is appropriate. What do you think? Is there classical evidence of this topic?

    Raymond Fokom · University of Yaounde I

    hello, there is not enough ellucidation of your methodology used to study your sample so it is not easy to take position. However when you study AMF, don't forget that some can take up to one year and more before get in symbiosis with the test plant. I think you must be careful while conclude that there is no AMF in your sample