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  • Amir Hosein Salmanpour added an answer in SAP 2000:
    How can i model a brick masonry school in SAP 2000 and perform pushover analysis on it?

    I have the drawings of the school and i need to model it on sap 2000 and perform pushover analysis on it

    Amir Hosein Salmanpour · ETH Zurich

    Your best chance is to use the so-called equivalent frame approach. There are many papers regarding the implementation of EFA by SAP2000. For example, I'll refer you to 
    Pasticier L, Amadio C, Fragiacomo M (2008) Non-linear seismic analysis and vulnerability evaluation of a masonry building by means of the SAP2000 V.10 code. Earthquake Engineering and Structural Dynamics 37:467-485

  • Adam N. Letchford added an answer in Multicast:
    Is there any optimization model for Steiner tree?
    I proposed an algorithm for multicast in smart grid and I want to compare it with the optimal tree. I tried to to write a model by myself but I finally came up with shortest path tree instead of Steiner tree. Any suggestions will be appreciated .
    Adam N. Letchford · Lancaster University

    You could try these papers:



  • Sharad Purohit added an answer in R Programming:
    What are the other methods to analyze microarray raw or processed files other than R programming?

    Microarray from ncbi-GEO  or array express analysis. what parameters do we need to confirm to use data from already existing array files on databases? how to analyze those microarrays whose experimental conditions are same but platform used is different ?

    Sharad Purohit · Georgia Regents University

    You are talking about micro-array data from difference platforms and combining them to do some type of meta-analysis. if you are not a bioinformatics person then you have to acquire someone who is experienced in this type of analysis. it includes several normalization steps as suggested my Dr. Black

  • Waqas Imran added an answer in Analysis:
    How should we handle missing responses?

    What is the ideal treatment of the responses in which the respondents did not answer all the questions/field? Should we abandon these partially filled entries altogether or take the answered fields in our analysis? I am not sure. Kindly help.

    Waqas Imran · Sustainable Development Policy Institute

    Before regression or any tpe of prediction, idealy, system should be free of system missings. more over, usually slopes (not with all models) are estimated after automatically ignoring the missing values (some times user missing as well as system missing or not applicable case). But for exploratory data analysis these are being reporting (non response/user missings/missed options/items of the questions). Main reason for reporting missing values in descriptive/bovariate analysis is that they have their own background and theory. World banks' "power of Survey Design" and Sharon Lohars "sample design (like this title)" well described the backgrounds of missing values. 
    My personal openion is that they must be reported during exploratory data analysis. But befor going toward multivariatee (regression only) such catagories can be excluded and merged with system missing for facilitation of practical and clear interpretations.

  • Are there clients/ patients who are more or less receptive to Motivational Interviewing counseling?

    I am wondering what is known about possible characteristics (e.g. demographics) of clients/ patients that influence the receptivity of persons to MI counseling.

    John Lakvold · MultiCare Health System

    I agree with with you, Sylvia, about substance use clients. I am a firm advocate of MI for substance use clients. I was referring to clients with schizophrenia and other psychotic symptoms who have little or no insight into reality. It is hard to motivate them to see a reality that different  from their world of fixed, false beliefs that seem so true to them.

  • Daniel McNeish added an answer in ANOVA:
    How robust is ANOVA to deviations from normality?

    I am analysing fish consumption data in a 2 factor design (predator species, 2 levels + prey species, 2 levels). The consumption data (number of prey eaten) is not normally distributed so I have been trying to use GLMs to establish whether there are differences in consumption of the prey species by the 2 fish. Initially, I used a Poisson error distribution and switched to quasi-Poisson error when I found the data to be overdispersed. However, the quasi-Poisson GLM is returning no significance for any factor, despite there being no overlap of error bars when I create a barplot of the same data (indicating that significant differences are indeed present).

    I have therefore tried an ANOVA on untransformed data as some articles in the literature claim that ANOVA is robust to deviations from normality. Would love to hear some thoughts on this to help me decide on how to continue?

    Thank you!

    PS. All analyses are being carried out in R.

    Daniel McNeish · University of Maryland, College Park

    In addition to the feedback you've already received, another aspect you might want to consider is if the overdispersion in your count data might be due to zero-inflation.  Perumean-Chaney, Morgan, McDowall, & Aban in the Journal of Statistical Computation and Simulation showed that not accounting for excess zeroes increased Type-II errors. Determining whether a zero-inflated model is preferable can be assessed with Vuong's test which is available in R. 

  • How can I measure the droplet size of nano-emulsion by scanning electron microscope and transmission electron microscope?

    As I am doing the experimentation on preparation of nanoemulsion (oil in water) and we have SEM and TEM analytical techniques So can I use these techniques for droplet size measurement.

    Vladimir Dusevich · University of Missouri - Kansas City

    You may want to try Quantomix capsules:



    They allow observation of wet specimens in conventional SEM. I do know they were used for emulsions, but I do not know if they allow resolution good enough for your purposes. 

  • What is the easiest and shortest method for determining crop coefficient and evapotranspiration?

    Is there any software or through lysimetric method

    Helene Unland Weiss · Mexican Institute of Water Technology (IMTA)

    CROPWAT is a FAO software used for calculation crop water requirements. It includes a database of previously derived crop coefficients for common crops, also documented in FAO publication no. 56. If you have access to the necessary climate data (min. and max. temperatures, relative humidity, wind speed, solar radiation) for your site of interest, you can use CROPWAT to estimate reference crop evapotranspiration (ETo) which then you can use to calculate actual evapotranspiration of a specific crop by multiplying ETo by the crop coefficient.

    However, if your goal is to actually determine (calibrate) a crop coefficient for a specific crop yourself, you would need to measure the actual crop evapotranspiration (ETr) by a direct method (lysimeter or micrometeorological methods like eddy correlation,Bowen Ratio/Energy balance, or scintillometry) and at the same time measure the standard climate variables mentioned above with an automatic weather station in order to determine the corresponding ETo. Crop coefficient Kc = ETr/ETo

  • Julie Fesenmaier asked a question in IRB:
    Citations for creating a de-identified medical dataset that can be pre approved by the IRB?

    I'm looking for best practice in creating a generic database for students using medical data.  I need this to be more than removing the 18 HIPAA variables.  How do you protect the incidents that have a small occurrence? 

    thanks, jf

  • Can anyone recommend published articles about nanotechnology in agriculture?

    Agriculture is an area where new technologies are often applied to improve the yield of crops. Nano Agriculture involves the employment of Nanoparticles in agriculture. These particles will impart some beneficial effects to crops. The emergence of nanotechnology and the development of new Nanodevices and Nanomaterials open up potential novel applications in agriculture and biotechnology. Nanoparticles are materials that are small enough to fall within the nanometric range, with at least one of their dimensions being less than a few hundred nanometers.

    Christian Dimkpa · International Fertilizer Development Center (IFDC)

    Find some resources here


  • What are the points I should consider while designing the ligand receptor assay on an adherent cell line using flow cytometry?

    The hormone binding reaction was initiated by addition of fluorescent tagged natural ligand to each in 6 well plate (4 to 5 lac cells/ per well 6 well plate). Incubations were performed in triplicate for 30 min at room temperature. After incubation ,cells were scrapped by cell scrapper. Cell suspension was centrifuged 1000g 10 min at 4 C, then discarded the supernatant and cells were fixed in 4 % PFA over ice for one hour. After one hour PFA was discarded after centrifugation and cells were suspended in facs buffer and analyzed according to convenience in few days. I have doubt here about washings and fixation, whether they are essential or it can be avoided? If essential when i should perform

    Ganesh Suresh Jedhe · CSIR - National Chemical Laboratory, Pune

    Dear Slobodon Sir, cells doesn't detach very easily with enzymatic as well as non-enzymatic way. Alternatively, I have tried to do the above experiment in another way. The cell line I am using is clone 9. In alternative way, I am detaching the cells by PBS -EDTA. And incubating the cell suspension in incomplete cell culture media with desire fluorescent ligand at 37 degree 30 min. After 30 min, I centrifuge cell function rapidly for short duration, 15000 g 30 sec. Then discarded the Supernatant. The cell pellet was immediately suspended in PBS and analysed cells by facs. I am getting signal. And I feel this alternative method little cumbersome. Whether this alternative method I have used is scientifically correct or there is need to add some steps? Thanking you. 

  • Gonzalo Fernández added an answer in Brucellosis:
    At what seroprevalence level the Bovinr brucellosis vaccination is recommended?

    For Bovine Brucellosis eradication program whatis the seroprevalence level that warrants the necessity of vaccination program.

    Gonzalo Fernández · University of Santiago de Compostela

    Vaccinate not only depends on the prevalence, also of the possibility of controlling trade in animals, farm biosecurity etc. If unable to perform them is more advisable to establish a vaccination program because the program test and sacrifice will fail

  • Conceição Costa added an answer in Propaganda:
    How can we identify propaganda and publicity in Public Relations?

    The question in other words is that even having clear cut academic definitions of Advertising, Propaganda ,Marketing , and Persuasion, it is very hard to differentiate them from Public Relations practices.Any tips?

    Conceição Costa · Universidade Lusófona de Humanidades e Tecnologias

    Annette I agree with you about what good PR should be. But in practice, if you look at media relations, for instance, why companies that invest in it have usually more news coverage (more control over media)? If you work in a company with economical interests, not a social cause I would say that your job is to create a positive attitude from Publics in your company. So why is it so different from Marketing. Is part of it in any book or framework of the Marketing.

  • Safarzadeh-Amiri Ali added an answer in Benzene:
    Why does the color of benzene change when interface with uv lamp and what can I do to prevent of this?

    I am working on advanced oxidation processes.

    Safarzadeh-Amiri Ali · Trojan Technologies

    Hello Reza,

    I noticed you mentioning in one of your postings that you do not have access to HPLC; HPLC would be the preferred choice for what you are doing: and sugested GC because I thought it would be available in the chem. dept. and I have seen a few when I did my B. Sc. at Sharif more than 30 years ago.

    Best regards


  • Surendra Nath asked a question in Orchids:
    Cna anyone tell me how to practically do in vitro propagation for orchids using seed?

    I have got Coelogyne pods and Knudson C medium for orchid seed germination, but since the seeds are too small and fibrous to handle, feel it extrmely difficult to do and sow uniformly on the medium...

    shall i prepare the medum on petriplates or jam bottles....

    sufficient literature is available but I feel practical difficulty........please help......videos can be provided........for convenience............

  • Shane Duignan asked a question in Androgens:
    Why is the free androgen index not suitable for males?

    The literature states that the FAI is suitable for females but not really for males, where alternatively, the Vermeulen calculation is commonly used to calculate free testosterone.

  • Sharad Purohit added an answer in Silver Nitrate:
    How can i separate all the proteins from salt solution in a cell culture medium with bovine serum?

    I want to determine the binding of metal ions to salt and protein complex in cell culture medium .

    Sharad Purohit · Georgia Regents University

    as long as you do not have metal chelators or beta-ME you do not need to remove salt and proteins to do metal binding. although the proteins from FBS in culture may interfere in the metal binding.

  • Chaozhi Pan added an answer in Biodiesel:
    What is the chemical componds resulting in the yellow color in the cooking oil?

    Recently, I am focusing the pretreatment of crude glycerol from the biodiesel industry. After acidification, light white yellow floating layer could be observed. Subsequent hexane wash seem not to be able to remove the color because light yellow bottom layer is founded. Compared to that of filtration via 0.45 um Nylon membrane after acidification, the hexane wash shows very limiting ability of color removal. So I really want to know the chemical composition resulting in the yellow color in the cooking oil. Can anybody help to resolve this question? Thank you very much!

    Brief description of the attach figure. The smaller bottle is the filtrated sample after acidification while the large bottle is the sample after 12 hours` hexane wash following acidification. In the large bottle, the upper layer is the hexane while the bottom one is the aquatic layer. It seems very interesting that the hexane could be extract the color. Therefore, I am very curious about the chemical composition of the color prior to further microbial consumption test. There might be light issue when I took the picture but there are significant color difference between the hexane washed sample and filtrated sample.

    Chaozhi Pan · Nanyang Technological University

    Narashimharao Kondamudi, thank you for your recommendation. I will consider the activated carbon to adsorb the color-resulting substance.

  • Lingyun Zhao asked a question in Sensor Fusion:
    Use IMU (like gyroscope) to measure head direction of small animals?

    Hi, I'm considering using Inertial measurement unit (IMU) like accelerometer, gyroscope and magnetometer to measure head direction and rotation for animal behavior. This is a small animal and it moves in 3D. Ideally the device will be mounted on the animal's head and needs to be less than 20mm x 20mm x 15mm in size and transfer data by telemetry. Does anyone have any experience on this? Main consideration here is precision, drift, data output rate and whether to use hardware sensor fusion computations.

    I know a lot of people use IR tags or LEDs with cameras to do this. But since the animal can run upside down, it seems tricky/costly to build and calibrate a multi-camera system.

    Thanks a lot!

  • Paul Smeulders added an answer in Dark Energy:
    Is dark energy merely an illusion?

    According to a report by Carlo Iorio and Timothy Clifton, dark energy may be an illusion. And LTb model or variations of it can be promising candidates to get rid of it. What do you think?

    Paul Smeulders · European Commission - Joint Research Centre

    Dear Alfredo,

    Could you give me a reference to your work please.

    Best regards,


  • Abdelkrim Azzouz added an answer in Silica Gel:
    What happened to absorbent colorless silica gel if in effect when heated it turned to brown?

    Colorless silica gel heating in 120-140 oC for resuscitation. After it was observed that some of the granules change the color and turned to brown. Does it change color on absorption is effective or not?

    Abdelkrim Azzouz · Université du Québec à Montréal

    What was the heating temperature? Was your silica already used or contacted with organic compound before? High temperature beyond 250oC triggers organic compounds decomposition (pyrolysis in the absence of air). Controlled heating at 300-350oC under air (oxygen)  stream may completely regenerate your silica. If not, you may be dealing with an inorganic impurity, than can be easily removed through acid-leaching.

  • Yosef Daniel Huberman added an answer in Probiotics:
    Why is fish growth performance decreased at higher doses of probiotic?

    We found that the growth performance of Tor tambra was increased as increases the probiotic dosage from 0 to 10 mg/kg feed then growth was decreased when the dosage of probiotic increases to 15 mg/kg feed. Is there any one can explain why the growth performance was decreased at higher doses of probiotic? Thank you in advance

  • Rajesh Pandiyan asked a question in CZTS:
    Why we are unable to see any kind of rectification behaviour based on CZTS solar cell device?

    I am in need of your kind suggestions based on CZTS solar cell device. After optimising certain conditions, we fabricated the sc device as (SLG/Mo/CZTS/ZnS/ZnO/AZO) with and without metal top contacts on top of AZO. Upon measuring the IV characteristics curve (measured between Mo back contact and top of AZO layer), we are unable to see any kind of rectification behaviour both in dark and light. Both the curves appear linear near to the origin. By the way, we measured simple resistance between Mo and top layer using multimeter, it shows around 30 ohms, which makes us so astonishing. Kindly give me some suggestions based on fabrication of device and masking of back contact. thanks in advance experts

  • Sharad Purohit added an answer in T-Test:
    Can you do statistics on change in relative gene expression in qPCRs?


    I am trying to analyse some qPCR data and I am having a bit of trouble.  I am looking at change in gene expression of different genes comparing a drugged sample to an untreated sample.  I have 3 biological replicates and 3 technical replicates for each.  When I do a t-test on the relative expression comparing one group to another I don't get a significant result as the numbers are quite variable.  

    However I can see from looking at the delta delta ct values that the  change in expression is very close for each biological replicate.  Each replicate just has a different "starting point" for the gene expression.  (ie the relative expression is different but the drop or rise after treatment is the same).  Can do a ttest on the change in relative expression vs 0 (no change)?  For example the 2 groups would be 37.52, 33.97, 35.11 (sample - control)  VS 0,0,0. (control-control))  It seems like it would be bias in some way but I can't work out how else to compare the change in expression.

    Thank you

    Sharad Purohit · Georgia Regents University

    you can only use parametric tests (t-test, anova) for normally distributed data. for non-normal data loot into non-parametric tests.

  • Where can I find DIY piezoelectric transducers?

    Hi, I am looking for piezoelectric material or device suppliers who can do small batch prototyping transducer designs for customers at affordable prices.

    Anybody know or recommend a few?


    Xiang Yan · University of Massachusetts Dartmouth

    Thanks will give a call

  • Marga Cabrera added an answer in New Media:
    Does anyone know of research about Latin American new media? Is there any list of new media in Spanish?
    I'm studying the new models of digital journalism and entrepreneurship in Spanish. I did it for the Spain case, and I want to improve it to all the Spanish speaking countries. Do you know people researching the same? Do you know if there is any list of all the new media in Spanish?
    Marga Cabrera · Polytechnical University of Valencia

    Thank you Ana! Actually he is helping me :-)

  • Ciara Mckinley asked a question in Caco 2 Cells:
    Has anyone got any good tips for successful depletion of Caco-2 Glutatione by BSO in a 96well plate(adherent culture)?

    Has anyone got any good tips for successful depletion of Caco-2 Glutatione levels by BSO in a 96well plate (adherent culture)?

  • Kyle W. Bender added an answer in Lysis Buffer:
    Concentrating phosphoprotein samples using a centrifuge concentrator?

    I'd like to further concentrate a set of cell lysates and then be able to perform a western blot on these samples to look for phosphorylated Vs non phosphorylated protein levels.

    I am harvesting the cells (one t-75 flask's worth each time) using phosphosafe lysis buffer. Occasionally the protein concentration is (I think) too low to perform a western for phosphorylated protein, I understand that there are spin columns containing membranes that can concentrate my sample but wondered if a Speedvac centrifuge concentrator would cause any dephosphorylation of my samples?

    Kyle W. Bender · University of Illinois, Urbana-Champaign

    As long as you aren't hitting very high temperatures for long periods of time your samples should be fine.  I run my concentrators in a refrigerated centrifuge at 10 degrees Celsius. 

  • Maurizio Megliola added an answer in Transmedia:
    Has anyone done any research on trans media and expanded content consumption habits in TV series and film?

    I am working in a paper about transmedia and expanded content consumption habits in TV series and film. Has anyone done any research on the field?

    Maurizio Megliola · PIKSEL SpA

    Deep media? You found something here http://www.convergenceculture.org/weblog/2009/12/the_revenge_of_the_origami_uni.php

  • Can anybody help me with a kit that estimates mitochondrial protein levels ?

    The mitochondria is the primary target for oxidative stress induced by Cisplatin, resulting in loss of mitochondrial protein sulfhydryl group. We have some interesting data on Oxidative stress biomarkers - CAT, SOD and GPX. But, I need some help in estimating the mitochondrial protein level for better conclusion. ANy suggestions please ?

    Shaloam Dasari · Jackson State University

    Thank you Dr. Pardhasaradhi and Dr. Alexander for your valuable suggestions. I work with HL 60 cells (Acute promyelocytic leukemia ).