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  • Atefeh Ghanbari asked a question in Lung:
    How can obtain diameter of lung nodule?

    hi everybody
    I want to do lung nodule segmentation and  do this on small lung nodules (between 2 mm and 10 mm in diameter). I have some images that I got from LIDC.
    how can I obtain diameter of nodule in each scan? dose info.SliceThickness
    help me?

  • Mohammed Almahdi asked a question in Nasal Cavity:
    I want information about pathology of natural infection of nasal cavity and lung of goats?

    Bacterial pathology infection.

  • Jonas Johakimu added an answer in Geopolymer Concrete:
    What are the limitations of geopolymer concrete?

    Plenty of researches are focusing on geopolymer (e.g. alkali-activated fly ash) concretes, and review articles have claimed their advantages over OPC concrete. However, they've not been widely utilized in practice. Here comes the question, what are their disadvantages which limit their application?

    Jonas Johakimu · Council for Scientific and Industrial Research, South Africa

    Thanks Kamal for your useful information.  Is there examples where this technology has been commercialised?.

  • Asha Sathish asked a question in Biosorption:
    Why sulphuric acid is not used for the activation of biosorbent?

    Researchers working in biosorption for waste water treatment

  • J.E. Inetianbor added an answer in Antimicrobial Activity:
    Can i used commercial disc as positive control in agar well diffusion method?

    I want to screen antimicrobial activity of certain extracts, and i choose to do agar well diffusion method. For positive control, can I used the standard antibiotic and placed it on the agar, instead of using antibiotic solutions in the respective wells? thanks in advanced! =)

    J.E. Inetianbor · Federal University Wukari, Nigeria

    Yes you can use the commercial disc as you control but it is advisable to use the same experimental method for your control so that you can monitor  and draw your inference if same procedure is used for both the control and the experiment. In as much you can use the commercial disc method for your control, it is not advisable for this experiment but the agar well diffusion method will be better for easy comparison of parameters in the experiment. Hope this help.

  • Melissa Oc added an answer in Structural Models:
    Is it necessary for all latent factors in a structural model to have the same amount of parcel indicators, and parcelled using the same technique?

    I'm using 4-6 parcels as indicators for each of the 4 latent factors in my structural model. I parcelled the items in 2 factors using the internal-consistency approach (each parcel containing items from 1 subscale), and the other 2 factors using the domain-representative approach (each parcel containing a representation of items from all subscales). I would like to know whether what I have done is appropriate? 

    Melissa Oc · HELP University College

    Thanks Dr Steinmetz for your caution and suggestions. Perhaps I should clarify that I'm running covariance-based SEM, and my research is not so much concerned about the indicators and their latent factors than the relationship between latent factors. The reason I'm using parcels is to restore the unidimensionality of my latent factors that were measured using multidimensional scales, since I am interested in the factors as unidimensional ones. I hope I'm making sense. I referred to: 

    Todd D. Little, William A. Cunningham, Golan Shahar, and Keith F. Widaman. (2002). To Parcel or Not to Parcel: Exploring the Question, Weighing the Merits. Structural Equation Modeling, 9(2), 151–173. 

    Also, since my analysis is confirmatory rather than exploratory in nature, I reckoned that it would not be desirable for me to remove 'weak' raw indicators and only retain the best ones (my faculty members certainly do not like that). So parcelling was the way to go for me. Would you think that this is inappropriate? Your input is highly appreciated. 

    Thanks Dr Paxton, I should add that when I ran CFA for each variable, I used raw indicators but in the final full-fledge model, I used parcels as indicators.

  • Prashant Praveen added an answer in Ultra Performance Liquid Chromatography (UPLC):
    Is anyone using UPLC columns from other manufacturers on a Waters' system?

    Hi all,

    We have recently bought a Waters I-class UPLC system. I have heard that some columns from other manufacturers do not fit the Waters column inlet fitting. I nearly killed the ferrule by doing a test connection to a Thermo column (ferrule got stuck).

    Those using Phenomenex and Thermo columns on the system, do you simply change the PEEK ferrule to an appropriate one or swap out the whole fittings kit?

    Prashant Praveen · National University of Singapore

    Hi Liyan. Usually any column can be attached to any LC, but you do need the right kind of adaptors to prevent leakage. You may ask Thermo to check for you, they should be able to provide you the appropriate ferrules/adaptors.  . 

  • Soheil Mardani added an answer in Discrete Event Simulation:
    Does anyone know what is the best software tool for develop a discrete event simulation?

    There are free and paid tools that develop discrete event simulations , in particular we are looking for one that is easy to use but at the same time contains all the functionality required for such simulations.

    Soheil Mardani · Tarbiat Modares University

    It depends mainly what you want to do. For example if you want to model traffic system in microscopic level, I suggest Aimsun. If you want to model total airport, CAST is the best. If you want to model general manufacturing and logistics system I suggest Enterprise Dynamics which has open platform to design everything. 

  • Mohammed Almahdi asked a question in Nasal Cavity:
    Can anyone help me to get an article about [etiology pneumonia associated with nasal cavity and lung lesions in goats]?

    Especially bacterial etiology associated with nasal cavity and lung in goats.

  • Disha Soni added an answer in Polyoxometalate chemistry:
    Are POM structurally stable in acids? Do they get dissolve in 0.5M H2SO4?

    If they get dissolve in acids, any way out we can make them stable in acidic solution and insoluble ? Please suggest some readings.

    Disha Soni · The Central University of Rajasthan

    Thanks Lukas for your suggestions.

  • Benoit Charlot added an answer in PDMS:
    I am depositing metal on PDMS with adhesion layer using e-beam evaporator, but metal is not sticking well on PDMS. How to make them more stable?

    Metal- Cu/Al adhesion layer- Cr

    Benoit Charlot · French National Centre for Scientific Research

    dip PDMS on the back of an unpolished Silicon wafer for example

  • Batia Yaffe added an answer in Oral and Maxillofacial Surgery:
    What is the preferred rhytidectomy technique, SMAS pelication or SMAS Imbrication?
    Or are you using a combination of the two procedures?
    Batia Yaffe · Sheba Medical Center

    I think  imbrication and plication are just  different names for the same technique.

  • Philippe Urban added an answer in pH:
    Any possibility to retain enzyme activity at PH 4.5-6, which has optimum PH of 9?

    I Am working with uricase enzyme which has optimum activity at PH 9,But i want to use this enzyme in a reaction mixture of PH 5-6 ,is it possible to retain its maximum activity or at least 70% activity at this PH ,any possibility?

    Philippe Urban · French National Centre for Scientific Research

    Hello again Purva,

    Another possibility is to affect the activity of water by adding a chaotropic reagent into your buffer. Try to add 0.3 M up to1 M  lithium ion (for instance LiCl 1M). This chaotropic agent modifies the activity of water and hence the real meaning of the pH, So, maybe, shifting the pH optimum of your enzyme a bit down to the values that you are interested with.

    Best regards,


  • Zbigniew Kowalski added an answer in Landsat:
    In geothermal prospecting...which images and bands combinations do you recommend?




    Zbigniew Kowalski · Polish Geological Institute - National Research Institute

    For geothermal prospecting the best option will be utilization of Aster satellite with 5 TIR bands (10-14).

  • Muhammad Awais Khan added an answer in Bridges:
    How can I remove my offset signal?

    Hello Everyone,

    I want to measure my sensor reading coming out of my bridge circuit. But it has an offset signal. I am exciting my bridge with 2Vpp, 4Khz. I tried with high pass filter (1st and second order) but could help that much.

    I do not want to use a potentiometer. Because then I need to do calibration every time.

    Looking forward for your reply.



    Muhammad Awais Khan · Universität Bremen

    Paul I am using AD630 for modulation demodulation, First stage amplifier is AD8421, and Second is an instrumentation amplifier LT1229

  • Hajiram Beevi added an answer in Scaling:
    I applied data scaling for dataset... it gives less classifier accuracy compared to dataset without scaling... Why?

    In one article, authors said that classifier accuracy must be improved after applying data scaling.. why... that is not possible to my experimental results?    

    Hajiram Beevi · Jamal Mohamed College

     Thank you dude... I got the information what i need from your answer....

  • Yohan Farouz asked a question in Movies:
    Can anyone recommend a stiching + synchronization program for tiled movies with periodic temporal features?


    I made some movies of the same sample, as the field of view of my microscope was too small. I made sure there would be overlapping areas in my movies, but now I am looking for a simple software, plug-in or algorithm to stitch the frames together and at the same time be able to re-synchronize them.

    Does it exist already or should I make one on my own?


  • Reza Biria added an answer in Scientific Writing:
    How to administer paraphrasing tasks in EFL higher education?

    EFL learners have trouble deciding what strategies to use when paraphrasing scientific texts for academic writing purposes and this may lead to plagiarism unintentionally. is there any deep study on paraphrasing tasks and plagiarism prevention in EFL academic context? How many sessions do we need for administering paraphrasing tasks? and, what strategies should be taught to EFL learners to overcome paraphrasing difficulties?  

    Reza Biria · Islamic Azad University Khorasgan (Isfahan) Branch

    Dear ms. Shoyukhi,

    There is a wide variety of ways by which you can take care of paraphrasing. However, I personally found out that one needs basic cliche type structures that help remove signs of plagiarism. To access such structures, use the following site:

    www. phrase bank. Manchester. Uk. org

    I am sure you would find it useful.

    Best regards,

    R. Biria

  • Ariel Linden added an answer in R:
    Is there a post-hoc test for Kruskal-Wallis?

    specifically, I'm looking for one in R.

    Ariel Linden · University of Michigan

    Most people use Dunn's test after KW. In Stata there is a user-written program called dunntest that performs all the post-hoc combinations with adjustment for multiple testing.

    I hope this helps


  • Ariel Linden added an answer in Gender:
    Blinder-Oaxaca decomposition - Any step by step guide for newbies?

    I would like to use the Blinder-Oaxaca decomposition in my thesis. Since the topic of my thesis concerns gender inequalities among top-level managers, decomposing the gender wage gap would definitely be something interesting for my research (despite it being mostly qualitative). However, I have a severe knowledge gap in statistics and maths, as I am originally from languages and literatures...

    At the moment I can understand the idea behind it and when looking at the decomposition I can understand it as well. However, now I have to actually compute it, and I feel so lost!

    I have some basic knowledge of SPSS but I know that STATA has a command called oaxaca. Which software should I use?

    Is there any step by step guide that I can follow? Almost all the materials I come across become far too hard to understand at some point, e.g. Ben Jann's paper... :(

    Is it ok to only compute Oaxaca-Blinder, or should I calculate its alternatives (Reimers, Cotton, Neumark...)?

    If STATA is better than SPSS, what is the best manual to guide me through this task?

    Thank you in advance!

    Ariel Linden · University of Michigan

    Let me update my previous response and add some detail:

    Stata Journal 8(4):480--492 introduces the Blinder-Oaxaca decomposition for nonlinear regression models, using the command: nldecompose

    Stata Journal 8(4):453--479 introduces the Blinder-Oaxaca decomposition for linear regression models, using the command: oaxaca

    I hope this helps


  • Jonas Lüßmann added an answer in Vissim:
    How can I change the accelaration rate in VISSIM?

    For each situation, the accelation rate of vehicles must be different. I need to change it for the first vehicle in queue at signalized intersections, when the signal turns to green. Now, I came up with 8.3 ft/s2 , which need to be reduced.

    Jonas Lüßmann · GEVAS software GmbH

    Koordinierung von Lichtsignalanlagen unter Berücksichtigung der Progressionsgeschwindigkeit und Pulkmanagement auf Basis der C2X-Kommunikation zur Reduzierung von CO2 Emissionen

  • Verena Berger added an answer in Lifestyle:
    Does anybody know a scale to measure lifestyles?

    I am searching for a (fairly short) methodology to collect lifestyle information that can be used as the basis for aggregating consumers in cluster-based typologies.

    It must fit to european lifestyles.

    I know there is e.g. the LOV and VALS, but as lifestyles are not the main topic of my questionnaire they have to much items. 

    Is there an alternative?

    Verena Berger · Zurich University of Applied Sciences

    Dear Mr Paxton

    allthought the measurement scale developed by Gunnar Otte seems to fit best to my requirements, which instruments did you use? Do you have another suggestion for a simple instrument?

  • Yang Liu added an answer in Interferometry:
    Where can I get short lengths of Highly Nonlinear PM fibers for SC generation in particular for f-2f interferometry (2128 nm -> 1064 nm)?

    I am looking for PM HNF fibers for a f-2f interferometer to detect the offset beat of a frequency comb oscillator (frep = 80 MHz, 1560 nm). The f-2f interferometer should be build all in fiber. Further I don't know yet how the dispersion/nonlinearity profile should look like to achieve peak powers at 1064 nm and 2128 nm within the supercontinuum.I have found companies such as Sumitomo and OFS. However, the MOQ and pricing is quite high. Are there samples or fibers from other manufacturers available which might suit this application ? Many thanks ! Sebastian

    Yang Liu · East China Normal University

    Dear Sebastian:

    I think the scheme (in letter "Operation of an optically coherent frequency
    comb outside the metrology lab") wil help you.

  • Sohan Hazra added an answer in Luminescence:
    When we excite an ion with 379nm to obtain emission at 550nm. Is this a Down conversion emission?

    Because in some papers they diidn't denote as Down conversion instead they use the the term Luminescence with 379 nm excitation, although they use the term upconversion for the 980 nm excitation for the same 550 nm emission...here i m talking abt Er3+...Pls clarify my doubt

    Sohan Hazra · The National Institute of Science Education and Research

    Down conversion is 'The interaction of a photon with a medium in which it is converted into two photons of lower frequencies such that energy is conserved'. So you will have to check if intensity is increasing (approximately doubling from excitation to emission) which will indicate if one photon is breaking into two photons with higher wavelength. 

    Still, I don't know if it will clarify whether its a downconversion or simple luminescence.

    Best of luck.

  • Bilal Zargar asked a question in Statistical Significance:
    How to calculate statistical significance of %Tonic hind limb extension?

    Is there any way to determine the significane in case of ALL OR NONE response?

  • Shahnawaz Ahmad Wani asked a question in Organ Bath:
    How much sample of aorta/ trachea should i take to study biochemical assay like sod gpx ?

    Dear fellow research friends, i was to do biochemical assays of rat aorta and trachea,



  • Anoop Kumar Srivastava added an answer in Soil Analysis:
    Which is the most effective method of diagnosis of nutrient constraints in perennials?

    In perennial crops , identifying nutrient constraints is truly  a complex exercise. An entire range of diagnostic techniques are being used , starting from soil analysis , tissue analysis ( Using index plant parts ) , metallo-enzymes , deficiency symptoms as  morphological descriptors, juice analysis, trunk injection to floral analysis,  of late. None of them alone is sufficient  to identify the nutrient constraint precisely matching to field conditions. Every method has its own merits and demerits. With the result , it is  often questioned that the currently available methods of diagnosis of nutrient constraints , are more inclined to diagnosis for the next season , overlooking the problems in the current season  standing  crop . This kind of constraint in diagnosis is so rampant in perennial crops. I wanted to know from researchers across , how to solve this so complicated issue?.

    Anoop Kumar Srivastava · Central Citrus Research Institute ( Formerly National Research Centre for Citrus )

    Thanks Dr Rao , yes indeed . Based on soil test- crop response studies under grid -based soil fertility valuation , we are  now one step ahead to develop decision support system for soil test -based fertilizer recommendation in citrus . This is how , we trying to make soil testing more more  meaningful  in the context of formulating fertilizer doses. Off  course ,  leaf analysis has own precision in such exercises when compared with conventional soil testing program.  

  • Adimalla Narsimha asked a question in Fluoride:
    How to calculate saturation index of fluoride, calcite and provide software details?

    How to calculate saturation index of fluoride, calcite and provide software details ?