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  • Zhenghui Li added an answer in Transcriptome Sequencing:
    Is it correct to compare the FPKM of two treatments if the nunmber of paired end reads obtained for their transcriptomes differ drastically?

    If  a Susceptible and a Resistant plant transcriptomes are sequenced in different batches and if the coverage obtained for one is say, twice that of the other, how correct is comparing the FPKM for particular genes since the no. of million reads for each sample differs greatly?

    Zhenghui Li · Geisel School of Medicine at Dartmouth

    It is possible in your case. However, if your read length is way too differ, i.e. 50bp vs 100bp, then I would use a second method, such as DESeq to further validate your comparison.

  • Muhammad Raisul Alam added an answer in Smart Grid:
    How can we model 'Load Shifting' mathematically?


    As you know, in Smart Grid, customers can reschedule and shift their electricity usage to other hours in a day. I would be grateful if you inform me about any papers in which the mathematical model of such 'Load Shifting' has been presented?


    Morteza Shabanzadeh

  • Imran Sadiq added an answer in Calcium Phosphates:
    How do I calculate lattice parameters and crystallite size of beta tri calcium phosphate from XRD data?

    How to calculate lattice parameters and crystallite size of beta tri calcium phosphate from XRD data

    Imran Sadiq

    Use scherrer's formula to calculate the crystallite size of your material from xrd data...this can be calculated by taking the full width half maximum of the highest peak in your xrd data....While lattice parameters can be calculated by adopting the method mentioned in BD Culity book...2 theta values of xrd data will be used to get lattice parameters and hkl values.....

  • Ibrar Siddique asked a question in Gels:
    Hello everyone, I am working on Alzheimer disease and i planning to show the Abeta42 level in the mouse brain homogenate by western blotting?

    For this western blot, i am running the tricine-sds-page. I run the gel until the 10KD band of the ladder has traveled half of the gel. But, when i go for the commassie or silver staining, i dont see any band after the 10KD band. Lower molecular weight proteins does not appear. Should, i proceed for the western blotting ? For this tricine-sds-page, i am following the nature protocol (Schagger 2006)

  • Mauro Colombo added an answer in Cognitive Training:
    Does anyone know of research on cognitive training for older adults in the context of compensatory changes in the aging brain (e.g. HAROLD, PASA)?

    I'm looking for the research verifying if the training-induced changes in cognitive task performance are connected with the changes in human brain, in terms of compensatory patterns, as PASA or HAROLD (or some other).

    Mauro Colombo · Golgi - Redaelli

    The abstract is relevant indeed; it cues towards the extension of a "prosthetic" approach inspiring also Cognitive Rehabilitation, as well as overall care, balancing cognitive impoverishment [according to "GentleCare" model by Moyra Jones].

    Thank you Paul, Mauro

  • Timothy A Ebert added an answer in Metal Foams:
    Can any one tell me what sample size should I use for mechanical properties testing of metal foam?


    Can any one tell me what sample size should I use for mechanical properties testing of metal foam? Some have followed sample size of say width (10 times pore size) while some say the width should be at least 7 times the pore size. 

    Can I use width of 7 times the pore size for compressive testing ?

    Timothy A Ebert · University of Florida

    It depends on the precision necessary for the estimate. There are several related ways to work this. A simple form of this question is to determine the maximum difference where you are happy to decide that there is no difference. So if pore size of 5 takes 2 kg/cm2 to deform, while a pore size of 6 takes 2.005 kg/cm2, is this a meaningful difference in the context of your problem?

    Another way to ask the question is to understand that there is an inherent variability in your data. If you measure pore size for 1000 pores in your sample they will not all be exactly 5.0000000000000 microns in diameter. Possibly your manufacturing technique is very consistent, and pore size differs by only a few molecules and that is below the ability of your equipment to measure. But there will be variability. To this variability are a range of other factors. Small changes in temperature, how you handle the equipment, micro impurities in your sample, and the list goes on. To this is added variability due to sampling. If I take 4 samples from a Normal distribution and 4 samples from a uniform distribution, you will not be able to tell me which set of samples came from which distribution. As you take more samples, it becomes more likely that your estimate of mean and variance will accurately reflect the population mean and variance. Play with a few random number generators to work this out.

    There are some web resources that will provide sample size estimates. GPower is one such tool. However, they often want information that is not available.

    Another option is to run your experiment and take as many measurements as possible. Run the data analysis and figure out how many samples you should have taken. Redo the experiment if necessary. This is not always a good solution because sometimes you get a very different answer when you rerun the experiment. However, if you get a different answer, then maybe the project needs more planning.

  • Aref Sobhkhizy added an answer in Housekeeping Gene:
    Housekeping Genes: which one is the best?

    there are some genes accepted as internal control for gene expression analyses but nowadays some researchers say expression of these housekeeping genes are varying from a tissue to other or their expression patterns are different among donors of the same tissue...
    I'm working on expression of a special gene using Realtime technique but i'm not sure which housekeeping gene is the best one.
    I had read that GAPDH has some variety in expression ... so I have tow remained choices ... Beta 2 microglobulin or Beta actin ...
    and how about 5S and 18s
    any one please help me to decide ... thanks in advance

    Aref Sobhkhizy · University of Tabriz

    Dear  Prescott Deininger and Dear Adam Brazzle

    I work on Breast cancer Cell lines and tissues also I work on circular RNAs of Breast Cancer patients... which one should I use?


  • Wilfried Musterle added an answer in Didactics:
    Which are, in your opinion, the most important issues of modern didactics?

    Didactic has long been constructed as a separate field of study, and today is probably the most advanced pedagogical discipline. However, not only in my opinion, but in opinion of most famous educators in the field of teaching and didactics are expected in the present and near future many fundamental review. Compared to most other inherited or new components of school and many relations that exist within the school system, teaching is essentially little changed, although it is constantly upgraded, refined, modernized, etc.

    Wilfried Musterle · Max-Born-Gymnasium

    Teaching should be sustainable which means that children and students know for a long time what they have learned. More and more teachers are confronted with a super market attitude of children, students and their parents. They only want the degree but they do not want to learn and they are not curious in knowing the facts of the subjects. In this case will all the new ideas fail but this attitude is zeitgeist. 

    More didactically fire work, more computers, more tablets, more experiments, more debating, more fun, more diversion and distraction are not constructive. Learning is a hard job for the children and not always funny.

    What helps in such situations is care and attention to the children. A teacher should attend the children with love, knowledge and wisdom. The person counts not the computers. The technology is waiting at home, the parents not always.

  • Ying Henderson added an answer in Dose Response Curves:
    Synergistic vs additive stimuli if one stimulus is binary?

    A quick question about scientific semantics regarding interaction of stimuli: I have two stimuli, A and B that induce quantifiable effect E. A is a drug and shows a dose-response curve, B is a cell-culture condition (e.g. 2d vs 3d) and therefore a binary categorical variable.
    The effect of both stimuli together is less than the sum of the two separate effects (E.g. E|AB < (E|A +E|B) for relevant doses of A. How do I describe the interaction, as additive or as synergistic? My gut feeling would say additive, as the combined effect is lower than the sum but I'm not sure.
    Which is the 'safest' formulation? Would you say it's additive until you can show synergism?

    Ying Henderson · University of Texas MD Anderson Cancer Center

    Put your numbers in Calcusyn software, it will calculate it for you.  If the combination index (CI) is equal to 1, additive effect.  CI <1, synergistic effect.

  • Erika Mendes Graner added an answer in Cell Aging:
    Could telomere length be restored in aged plant cells?
    Would it be possible to restore the telomere length and telomerase enzyme activity in the cells of a somatic embryo derived cell reprogramming to a totipotent stage in aged epidermal cell? Taking into account that aging of the target cell to somatic embryogenesis was characterized by the presence of short telomeres and low activity of the telomerase enzyme.
    Erika Mendes Graner · University of São Paulo

    Dear Alshibly, there is no problem. Thank you very much!!

  • Felice Romolo added an answer in Incubation:
    How can I calculate gas flux from a soil incubation study?

    I have analyzed CO2, CH4 and N2O concentration (ppm) from my incubtion bootle (250ml) containing 25 gram soil at 60% WHC( equals 7ml water). Now, how can I calculate gas flux from incubation experiment. Can someone specifically provide me details (formula) to calculate the flux and what should be the final unit.

    Felice Romolo · Università degli studi di Palermo

    Good evening, at first you have to say wich instrument you will use

    2)If you will use an IRGA you have to say if is a dynamic or static system.

    3) For CO2 you can use alkali traps

    In few words when answered me the instrument I can help you.

    Final units for this porpouses you can use mg CO2 g-1 soil day -1

    micro moles CO2 g-1 soil day -1


  • Konstantinos Voskarides asked a question in PowerMarker:
    I calculated AMOVA table through PowerMarker software but p-values are missing. Anyone knows how can I get them?

    Population genetics

  • Mohammad Ayham Hakkoum added an answer in Prosthodontics:
    Can anyone recommend a study on prefabricated round bar attachment for retaining overdenture?

    Can anyone recommend a study on SFI bar attachment for retaining overdenture?

    Mohammad Ayham Hakkoum · University of Kalamoon

    Retention force of plastic clips on implant bars: a randomized controlled trial:


  • Daniel Gaida added an answer in Automation & Control:
    Does anyone have screendumps or documents from the settings on communication of opc server/opc client in Siemens S7-300 using a CP5611?

    I am trying to set up a connection between an OPC client (using the MATLAB OPC toolbox) and a PLC S7 300 as OPC server through a CP5611 Profibus card. The problem is that OPC server does not show up in the list of available servers when I type in MATLAB: >>hostInfo = opcserverinfo('localhost')

    I think that I set all of the configuration of OPC toolbox in MATLAB (such as opcregister and all of security setting in Component Services on the PC's operating system), but when i want to add a host in OPC toolboc, i encounter the following error

    Does anyone can help me or have screendumps or documents from the these settings ?


  • Chamishara Rathnayake asked a question in Concrete:
    How to use design of experiment (DOE) for three factors ??

    I am doing an experiment on corrosion in reinforced concrete. I am using half cell potential equipment and impressed current method to accelerate the corrosion. the factors i am considering for my experiment are concrete cover depth, concrete permeability and moisture content. Can anyone explain me how to use DOE for my experiment using above mentioned factors. 

  • Haitham Hmoud Alshibly added an answer in Innovation Systems:
    How different is the innovation ecosystem of European companies than that of American companies in emerging economies? Here's a note on EU firms.
    I did this research last year to understand the approaches of European companies engaged in R&D activities in India. I wish to take it further in deciphering the nuances of EU firms, and contrast that with American firms. Any suggestions on the areas to look at?
    Haitham Hmoud Alshibly · Al-Balqa' Applied University

    sorry I do not have the expertise to answer this question.


  • Haitham Hmoud Alshibly added an answer in Congresses:
    How many articles presentation in congress?
    There are far more types of audiences than there are types of presentations because audiences are made up of people and people come in innumerable flavors. Individuals could be invited to speak to groups all across the country. What the individual says and how they may say it depends on the makeup of those groups. They may ask you the individual to address a room full of factory operations managers who have no choice but to attend their talk, you they may go before a congressional committee looking into various environmental issues. When an individual stands up to deliver a presentation before an audience, its essential that the audience know who the presenter is, why they are there, what specifically they expect to get from your presentation, and how they will react to your message. You wont always be able to determine these factors, but you should try to gather as much background information as possible before your presentation. There will be times, especially with presentations that are open to the public, when you will only be able to guess.
    Haitham Hmoud Alshibly · Al-Balqa' Applied University

    sorry I do not have the expertise to answer this question.


  • Haitham Hmoud Alshibly added an answer in Community Structure:
    What are the consequences of an unbalanced design when using db-RDA?
    I am analyzing taxa community composition in relation to explanatory variables by distance-based redundancy analysis (db-RDA), based on Bray-Curtis dissimilarities on untransformed abundances, with R. I have a stratified design (3 stream reaches) and initially I had the same number of replicates per site. As predictors, I'm using, among other variables, treatments 1, 2, and 3. At the end of the study, I lost all replicates from, say, treatment 1 at a given site, and a couple of replicates per site for, say, treatment 2. I ran the db-RDA model for sites combined (but with permutations stratified within sites), and then ran a separate model per site. What are the consequences of an unbalanced design when using db-RDA?
    Haitham Hmoud Alshibly · Al-Balqa' Applied University

    sorry I do not have the expertise to answer this question.


  • Claes Richard Fredö added an answer in Operational Amplifiers:
    How can I keep a low-noise operational amplifier in stable condition?

    I find many strange problems in using ultra-low noise operational amplifier. It's very difficult to keep it in stable condition. The power supply is carefully designed and optimized. And everything is realized according to suggestions given in datasheet. I can't get noise performance given by ADA4898's datasheet. 

    Claes Richard Fredö · Qring Technology Intl. AB


    Again, I advice a grain of salt as I do not have any electronics backround. Some thoughts for what they are worth

    A) The 100mV/2V amplitude behavior.

    i) Narrow PCBs conduits and high load introduce additional resistance. On the same note, a 'cold soldering', i.e. soldering that did not cure properly, may introduce similar phenomena.

    ii) Have you excluded grounding problems that cause DC shift across the PCB and offset amplifier zero points?

    iii) I have never tried it but, as a thought, cooling spray that you use to test soldering - why not try spraying individual components with it when operating at high load? If there is a power related change, it would be logical for it to change when greatly cooled. This way you may get lucky and find if one or more components affect your results.

    B) On a more general note as theory and practice are off.

    Have you eliminated the influence from exterior excitation? To exemplify, capacitors act as poor microphones and pick up sound. I imagine that resistors react to mechanical load.


  • Peter Häuptle added an answer in Transmission:
    Can anybody provide a PST-16 Test system with data? Or German Test system for transmission or distribution network with data?

    I need it to use for assessment of steady state as well as dynamic simulation. 

    Peter Häuptle · Hochschule Heilbronn

    I have parameters for implementing an IIR-FILTER for simulating a PSTN-Network. Does this help you?

  • Igor Goliney added an answer in Absorption:
    How to calculate absorption coefficient from absorption cross-section of quantum dot ?

    Hiii everyone .. Could you please tell me how to calculate absorption coefficient from absorption cross-section of quantum dot 

    Igor Goliney · Kiev Institute for Nuclear Research

    Multiply it by the concentration of the quantum dots. 

    That is if you have enough quantum dots to speak of the absorption coefficient

  • Haitham Hmoud Alshibly added an answer in Digital Heritage:
    Can anyone suggest any archive quality slide scanners?
    What is the best quality archival slide scanner now that the Creoscitex and derivative Kodak top-end scanners are out of production?
    Haitham Hmoud Alshibly · Al-Balqa' Applied University

    sorry I do not have the expertise to answer this question.


  • Haitham Hmoud Alshibly added an answer in Blood Flow:
    Are there any novel methods for assessing local O2 consumption and blood flow in skeletal muscle by near-infrared spectroscopy?

    Currently, local O2 consumption and blood flow in skeletal muscle are assessed by use of near-infrared spectroscopy through venous and arterial occlusion techniques, nevertheless such techniques can't been used among some populations (frails elderly for example).

    Do exist some novel methods to avoid this problem?

    Haitham Hmoud Alshibly · Al-Balqa' Applied University

    sorry I do not have the expertise to answer this question.


  • Haitham Hmoud Alshibly added an answer in Research Methods:
    What observational coding scheme is best for verbal and nonverbal communication?
    I'm researching validated coding schemes for videotaped clinician-patient encounters that would take into consideration both verbal and nonverbal communication. Does anyone have feedback on using the Roter Interaction Analysis System (RIAS), the Verona Medical Interview Classification System (VR-CoDES), the Measuring Patient-Centered Communication scale (MPCC), or other systems?
    Haitham Hmoud Alshibly · Al-Balqa' Applied University

    sorry I do not have the expertise to answer this question.


  • Haitham Hmoud Alshibly added an answer in E-Commerce:
    Who at AUT University has a research focus on e-commerce?
    I am preparing to start my Masters in Computing and Information Science in 2014. I am keen to connect with other people interested in the challenges I have outlined in my ResearchGate profile.
    Haitham Hmoud Alshibly · Al-Balqa' Applied University

    sorry I do not have the expertise to answer this question.


  • Haitham Hmoud Alshibly added an answer in Performance Analysis:
    How to compare performance of two different systems (methods/techniques) when they produce results that follow different distributions?
    We have two techniques/methods/algorithms. One produces results that follow normal distribution; however, distribution of the results of the other is not known. If we want to arrive at some conclusion on performance comparison, whether two systems are same, different, or one is better than other, which statistic-test or sequence of statistic-tests need to be performed?
    Haitham Hmoud Alshibly · Al-Balqa' Applied University

    sorry I do not have the expertise to answer this question.


  • Haitham Hmoud Alshibly added an answer in Caenorhabditis elegans:
    Can anyone help with the maintenance of C. elegans strain JJ1244 (mex-5/6 mutant)?
    I have to perform some assay on the JJ1244 strain (mex-5/6 mutant). The worms segregate into Wild type / Unc / bag of worms. The phenotypes of the unc are well described in the Wormbase.

    But to maintain the strain I have to select the Wild type looking worms (which are genotypically hetero-zygotes). the problem is that bag of worms ( nT1 / nT1 ) are also Wild type looking and they segregate into bag of worms only so of no use.

    My question is : Do any one have a sense or experience or suggestions for recognizing or differentiating the Heterozygote Wild type looking from the Bag of Worms Wild type looking?
    Haitham Hmoud Alshibly · Al-Balqa' Applied University

    sorry I do not have the expertise to answer this question.


  • Molly Tyner Boland asked a question in Cell Signaling Pathways:
    Can phenylarsine oxide dissolve in ethanol?

    I cannot use DMSO because it will interfere with the cell signaling pathway I am looking at.