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  • António J. R. Neves asked a question in Image Coding:
    What are the most efficient algorithms for lossless compression of Bayer Color Filter Array Images?

    I prepared a study showing that the raw Bayer images have special properties due to the nature of the pixel information and present a challenge for general purpose image coding algorithms. I'm interested in the most relevant specific algorithms developed for lossless compression of these images. 

  • Alexandra Tripp added an answer in Nursing Research:
    In an acute care setting, does completing hourly rounding compared to not completing hourly rounding affect patient fall rates?

    We have had an increase in pt falls on the inpatient acute rehab I work on. I am looking for nursing research articles asking if pt rounding compared to not completing patient rounding affects patient fall rates. Thank you

    Lara Parenteau, RN


    RN-BSN student at St. Kates

    Alexandra Tripp

    Hello, Lara.
    In my experience, hourly rounding has decreased the incidence of falls.  However, hourly rounding alone is not a cure-all.  What has been a noticeable difference is facilities that institute the "NOWA" program (No One Walks Alone).  This was piloted by Kaiser in California, but has gone system-wide.  Basically, instead of assessing each patient for fall risk, each patient IS a fall risk.  Bed alarms and chair alarms are used for every patient, patients are assisted to the bathroom and staff remain with the patient (within reason), and patients who ambulated are assisted by staff.  Patients who are alert and oriented may "opt out".  I have attached a link below.
    I was skeptical at initiation, but the numbers are quite impressive.
    I realize it's a bit off topic from hourly rounding, my apologies.

  • Selim M. Sayah asked a question in Hydropower:
    While working on a new Hydropower project. Having flows&topo is there a deterministic/statitic method to the select the best design flow?

    While working on a new Hydropower project. Having flows&topo is there a deterministic/statitic method to the select the best design flow?

  • Sridhar Vadahanambi added an answer in TEM Image Analysis:
    How can I calculate the number of walls in MWCNT from TEM images?

    Using the interatomic distance. Please, if there is a reference, I'll be grateful.

    Sridhar Vadahanambi

    Raman spectra is only an indirect measure...since there are far too many variables like number of walls, chirality, nature and extent of defects which affects the location and intensity of Raman peaks.

  • Ka Kui Tong added an answer in Drosophila:
    Can we do real time expression of genes in Drosophila antenna?

    I want to check the expression of a gene at the johnston organ of Drosophila antenna

    Ka Kui Tong

    Do you mean live imaging on gene expression?
    you may try the MCP-MS2 system. but, one gene each time.




  • Thijs Dhollander added an answer in Tractography:
    What is the best program for HARDI diffusion data probabilistic tractography?

    I am working on human connectome HARDI diffusion data. In brief, the dataset has 1.25 mm isotropic voxels, 270 directions, 3  b-shells (1000,2000,3000) . I want to do seed-base probabilistic tractography. Since i am new to HARDI diffuison data tractography, which program is proper for my data?   Does MRtrix support multi shell data? which program support multi shell datas?

    Thijs Dhollander

    That's a difficult one to put a number on: it really depends on the tracking parameters you use.  Once you've obtained your FODs (which will take less time than a decent tracking process thereafter), the original quality of the data doesn't matter so much anymore, in relation to computing time for tracking.  The 2 "parameters" that will influence your tractography computing time the most, are (evidently) the number of tracks you request, but also the step size (smaller stepsizes require more steps per track, hence more computing time).  And of course, most of all, computing time is influenced by your available hardware.  MRtrix allows for multi-threaded processing for computationally intensive tasks such as CSD and (probabilistic tractography).  The overhead to generate the threads is very small in comparison to the gain in overall speed, up to the point where you almost gain a factor in computation time equal to the number of cores of your CPU; i.e. using 4 threads on a CPU with 4 cores, will result in a speed up close to a factor 4.

    What I'd say in general is this: once you've obtained your FODs by CSD, try running probabilistic tracking for a limited amount of tracks first (let's say, 10000 or so), and take note of how long that takes on your hardware setup.  This will quite easily allow you to extrapolate computing time for a larger amount of tracks (linearly).  Does that make sense? :-)

  • Ishtiaq Hussain added an answer in Metallic Glasses:
    Why fracture angle of metallic glass wire is different with different size?

    Recently, i have did tension test of metallic glass wires with two different samples.  the fracture angle of different size metallic glass wire is different like 

    the fracture angle of 130mm metallic glass wire is 48 where as the fracture angle of 136mm metallic glass wire is 51 why

    Ishtiaq Hussain

    Thank you very much sir , yes  this is a good paper and related to my question. thanks once again for your help.

  • Kun-Han Chuang asked a question in Galactose:
    Does anyone know whether galactose can induce expression of the protein under control of lac promoter in yeast?

    there is one paper "Galactose induces the expression of penicillin acylase under control of lac promoter in recombinant E. coli" published in Biotechnology letters 2003. This study is done in E. coli but I would like to know if galactose also can work on lac promoter in yeast, even just weak induction is fine. does anyone know something about this? any information is good for me. thank you

  • Nima Mohaghegh added an answer in Chromatin:
    How do you isolate or separate crosslinked chromatin fragments from the rest of chromosomal DNAs?
    We crosslink the nuclei with formaldehyde, followed by a restriction digest.
    Nima Mohaghegh


    I wonder if certain PTMs upon certain stimuli might make my IP inefficient or biased.

  • Alexandra Johnson added an answer in Agrobacterium:
    Could anyone explain the steps of doing serial dilution of agrobacterium culture, for example, from OD_600 of 1.0 to 0.25?

    Would I need to convert units from OD to volume or density of bacteria? Thanks!

    Alexandra Johnson

        I've never worked specifically with agrobacterium, so I don't know it's quirks and I hope I'm understand your question correctly... But generally, you can use the M1 X V1= M2 X Vequation from undergrad chemistry, where M=molarity or concentration(in this case, OD600 is our concentration) and V is volume. Generally you have your starting concentration(M1), your beginning volume (V1) and what OD you want to get to(M2) and just need to solve for V2.

       Going off your example, if you put 1 mL of your bacterial culture that you know the OD of (1), you could add 1mL of your culture to 3mL of whatever you're diluting it in:
    (1mL x 1 OD600)/.25 OD600= 4 mL.

        For serial dilutions, if you wanted to continually dilute it by 4, you would take 1mL from your .25 OD sample you just made and add it to another 3 mL volume of your solution.

    If you need the actual CFUs, then you just plate out dilutions and use that to back-calculate the actual bacterial density. 

  • Kar-Weng Chan added an answer in Pharmaceutical Formulation:
    Anyone familiar with placebo pills for method validation?

    Placebo pills are needed to form a matrix for pharmaceutical formulations. If my company does not have budget for it, is it possible to use sugar-free pills and/or panadol tablets to compensate for its use? Can they meet the minimum requirement? In my humble knowledge, they have some although not all of the characteristics of the placebo pills.

    Kar-Weng Chan

    Hi Bunleu, ur explanation is very informative. And it is very useful as I can learn much from it. I tried to ask from a local pharmaceutical company to gift me the bupre pills, they said their production has been banned. So I have no way but to outsource placebo pills in my locale. Still, haven't found one.

    I'm developing the said method for in-house purpose. In fact, we are trying to make use of the balance (1.5ml of 100ppm) of bupre std to produce something useful. The std was for LCMS method (blood) and it was completed. We tried to develop an HPLC method but we could not reach the target LOD. To utilize the std, it can afford qualitative work and thus I have to develop this method rather in a haphazard way. Not sending out for publication anyway. I'm aware that this work is too weak in its analytical rigour so we'll just keep it as a back up method when request arises. In future endeavor where true analysis is needed, the respective lab should verify it with bupre case samples.

    In our lab practice (not a research lab), we are not funded to do work that's not related to service. This is our headache. At any rate, thanks for intellectual sharing...

  • Constantinos V. Chrysikopoulos added an answer in Mass Transfer:
    Mass transfer coefficient and velocity effect?

    Hi all

    After a long time, i am in RG.

    I am having a fundamental understanding problem about the effect of velocity of fluid on mass transfer coefficient.

    As we know that as velocity increases, mass transfer coefficient increases because of fresh fluid elements coming into the mass transfer interface.

    If fresh fluid elements come to the interface, then mass transfer driving force will be higher and consequently molar flux will also be higher. If the velocity is further increased, driving force and consequently flux will further increase. That means mass transfer coefficient remaining constant.

    How fresh fluid elements increases mass transfer coefficient then? How to understand it physically? 


    Vivek Arora

    Constantinos V. Chrysikopoulos

    Please note that the concentration boundary layer thickness at the interface will decrease with increasing velocity (see Journal of Hazardous Materials, B97, 245-255, 2003).

  • Bridget Freisthler added an answer in Child Welfare:
    Can anyone recommend research on child exploitation?

    Any research on Child Exploitation, I'm currently reading through   what I can find to  assist me in finding my own tittle for up coming research in this area.

  • Guinevere Nell added an answer in Hermeneutics:
    Has hermeneutics had an impact on the social sciences?

    Back in the 1990s Don Lavoie and I edited two volumes on hermeneutics and economics.  Lavoie published Economics and Hermeneutics (Routledge, 1991) and I published Individuals, Institutions, Interpretations:  Hermeneutics Applied to Economics (Avebury, 1995).  Both had a small methodological impact on our "Austrian" School of economics colleagues.

    My question:  Are any of you aware of works on hermeneutics in the other social sciences -- sociology, political science, etc?  And, if so, have they had any type of impact?

    Guinevere Nell

    I have been coming across hermeneutics in Austrian-inspired (especially Hayek-inspired) economics more and more lately, some of which has cross-over with political science and other social sciences. As one example, consider the excellent recent book by F. Di loria, Cognitive Autonomy and Methodological Individualism. (Also see his paper, "Hayek’s The Sensory Order and Gadamer’s Phenomenological Hermeneutics," 2013.

  • Roberto Kasuo Miyake added an answer in Telangiectasis:
    Resilient Telangiectasias: do you search (and treat) the feeder veins?

    We've been removing feeder veins to treat telangiectasis since the 70's. From 2005 on, we've been finding those veins by augmented reality and treating them with CLaCS (a combination of transdermal laser, skin cooling and Dextrose75%).

    The prevalence of those feeder veins is significantly higher in a patient with telangiectasias comparing to a patient with no aesthetic concern on the leg (no visible telangiectasias or small varicosities)

    What is your opinion/experience?

    Roberto Kasuo Miyake

    This is a poster we've presented at the World Congress of Phlebology and where you can get more info about the question. Looking forward your opinion!

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: The progress of the treatment for chronic venous disease has been supported by CEAP, REVAS and VCSS. The correlation between the presence of vessels connected to resistant to sclerotherapy telangiectasias has also been discussed. None of the above described classifications evaluate the prevalence of small varicosities under telangiectasias - "feeder vein". We believe that the presence or not of a small varicosities under a telangiectagia affects the sclerotherapy result. The objective of this study was to use Augmented Reality to search "feeder veins" in areas that the patient complained about telangiectasias and use the same method in areas that the patient had no complaints about leg vein lesions. - Case-control study - December 2012 to March 2012 - Presence of small varicosities on the thigh with or without telangiectasias - 50 consecutive female patients - non-invasive Augmented Reality examination - detection of small varicosities under telangiectasias - exclusion factor was the presence of reflux in any segment of the saphenous veins (examined by duplex scanning) At least one varicosity was detected in all areas (100%) where the patient was complaining about telangiectasias. Prevalence of small varicosities in areas that the patient considered normal was 7%. This difference was considered to be extremely statistically significant (P value is less than 0.0001. We conclude that the prevalence of small varicosities estimated by augmented reality should be in the inclusion and exclusion factors of Sclerotherapy Treatment Studies
      World Congress of Union International de Phlébologie, Boston, USA; 09/2013
  • Victoria Negro asked a question in Latin:
    What literature could you recommend me about latin american colonialism between XVII-XVIII centuries?

    I am writing an article about cultural influence of the metropolis on latin american colonies. I mean, influence on literature, architecture, music... Do you know any sources?

  • Khurram Munir added an answer in Solidworks:
    What is the easiest way to regenerate a solid part from the STL file ?

    I have been trying to generate a 2D drawing from available STL file of a very complex geometry of a porous structure. I have tried to import STL file into Solidworks but it only gives a graphical view of the model from which generation of 2D CAD drawing is not possible. I have tried another software MeshLab but it only gave me a 2D drawing of one of the face of the modeled structure.

    Khurram Munir

    Dear All, 

    I really appreciate your feedback on this matter. Your suggestions are really good, I am going to try that for sure. 

    @MArio Hirz , Great suggestion. Thumbs up!

    Best Regards,


  • Aline Benso added an answer in EU & European Studies:
    When was the term "Revolution of Dignity" initially used in reference to the protests in Ukraine in November 2013-February2014?

    I'm doing a case study on Ukraine's Revolution of Dignity and want to find out when and who initially named it as such.

    Aline Benso

    A recent study by Castells, "Networks of Outrage an hope". Maybe this study can help you! 

  • Marcos Roberto Benso added an answer in Forestry:
    Are there empirical evidences to prove that the rain forests are actually the lungs of the earth?

    I am a researcher with interest in environmental forestry. It is often said that 'the rain forests are the lungs of the earth'. I will like to know if there are empirical evidences to buttress that assertion.

    Marcos Roberto Benso

    As I said previously, there are evidences that the most part of atmosphere oxygen is formed in oceans. Emerson and Stump (2010) [1] showed that in northeast subarctic Pacific Ocean the summertime mean of biological production of oxygen was 24 mmol O2 m−2 d−1. I know that this answer is not in the focus of the question, but i thought that would be interesting show one of the great responsable of oxygen gas in atmosphere.

    [1] Emerson, S.; Stump, C. Net biological oxygen production in the ocean—II: Remote in situ measurements of O2 and N2 in subarctic pacific surface waters. Deep Sea Research Part I: Oceanographic Research Papers. Volume 57, Issue 10, October 2010, Pages 1255–1265.

  • Sophia Bardehle asked a question in Viral Transduction:
    Which viral transduction method works for GPF-labeling of Tcells?

    APC/Tcells isolated from MOG-immunized mice. During in vitro activation and expansion, I would like to transduce Tcells with GFP-encoding virus. 

    How can I stably express GFP in Tcells for in vivo imaging?

  • Thomas Nann added an answer in Quantum Dots:
    How can I modify the surface of CdSe/ZnS quantum dots with thiolated glucose ?

    I use toluene as solvent. Do you have any suggestions for the conjugation procedure of quantum dots and glucose molecules?

    Thomas Nann

    I think I know where the problem is: in the paper above, the authors use citrate coated silver particles. Citrate is a pretty weak ligand and does exchange very easily against thiols (actually you've got a disulfide, which is a not-so-good ligand). Ligands on typical CdSe/ZnS QDs are typically quite sticky and won't readily exchange against something  weaker. The solution is to use a two-step process as in the enclosed papers. This can be adapted quite easily to QDs and should do the trick. Let me know should you have difficulties and I might help.


  • Dac Dung Truong asked a question in Abaqus:
    Is there any way to reduce the oscilation of plate under impact loading in ABAQUS?


    I have tried to perform an plate subjected to impact load in ABAQUS, after impacting the plate have a permanent deflection, while the plate was still oscillating. So how can I reduce the oscillation of test plate in ABAQUS?

  • Victoria Negro added an answer in Bilingualism:
    Anyone know of any research on bilingualism on Twitter?

    I'm looking for research on how Twitter users negotiate which language to use when tweeting. Does their choice of language depend on the topic of the tweet? Does it depend on their audience? 

    Victoria Negro

    No, I don't. Maybe they use a language like english to improve their followers. Sometime they use one or other language depending on what they want to tell. I thibk this two options are correlated.

    Me, I use spanish to talk to people I know more; and other languages depending on the public (if they talk to me in their languages I answer in it) and on the topic. This last point, it depends if it is an specific topic that has something related to a country, like its history or culture; if I want to get more other audience, I write in two or more languages at the same time.

  • Céline Caseys added an answer in Hibiscus:
    How does the ploidy level in G. hirsutum x Hibiscus is observed? which techniques are used?

    How the ploidy level in G. hirsutum x Hibiscus is observed? which techniques are used?

    Céline Caseys

    One of the most frequently used method to measure ploidy in various plant species is flow cytometry and comparison to plant with known ploidy level. 

  • Grant Mitman added an answer in Moss Biomonitoring:
    Does anyone have some suggestions to ammend acidic soil to promote moss proliferation?

    any suggestions of useful gels or other additives or protocols?

    Grant Mitman

    I was thinking more along the lines of water retention agents

  • Ahmed Gaballah added an answer in Shoulder Joint:
    What are the forces involved in the shoulder joint?

    what are forces involved in shoulder joint any one can answer

    Ahmed Gaballah

    Dear Bhaskar

    this thesis may be useful for you

    The Role of the Scapula in Athletic Shoulder Function
    W. Ben Kibler, MD*

    Am J Sports Med March 1998 26 325-337

  • Marc Arakaki added an answer in QR Codes:
    Can you think of any ways that the use of QR codes has enhanced your experience of a place?

    Any particular places you've visited (museums, restaurants, tours, etc.) that made use of QR codes in a way that enhanced your experience?

    Can you think of any places that do not currently make use of QR codes that might benefit from implementing them?

    Marc Arakaki

    As the former editor-in-chief of our school newspaper, we attempted to use QR codes to direct people to other websites that contained more detailed information of the topic that you were reading. For example, our sports department created an online webcast summarizing the UH sports of the week. Then in the print issue, we included a QR code to direct viewers to the direct website of that online webcast. I think our use of QR codes not only supplemented our readers to our different forms of content, but also provided more viewership to our content as well.

    I can think of restaurants as being a business that could greatly benefit from using QR codes. The restaurant can provide a link on their menu that could direct customers to coupons or other ways that they could save money by dining at the restaurant. I think that would bring more customers to the business and more importantly, repeat customers that will tell their friends about it. 

  • Joana Boavida asked a question in Coral:
    What is a mesophotic community and should it include temperate reefs at mesophotic depths?


    there is a lack of a clear definition on mesophotic habitats as species. From the literature it seems that the term was initially (~2008-2009) used only for tropical and subtropical regions in the US and later extended into other regions worldwide, including temperate (mainly Mediterranean) areas. My question is wether people agree on what is a mesophotic community or habitat, and if the definition or the way it is used reflects an ecologically relevant community/habitat/concept?

    If it is related to light-dependence, than the temperate Mediterranean rocky reef communities should be included too, as they include light-dependent (with simbionts) corals/octocorals and coralligenous algae? From the literature it also steems that these ecosystems don't necessarily need to include reef building corals (e.g. some mesophotic reefs in Australia are described as having only or mostly octocorals, just like the temperate Mediterranean and nearby Atlantic "mesophotic" communities).

    Thank you for your thoughts on this topic.

  • Reza Kamalifard asked a question in Abaqus:
    How can I define contact between two rigid bodies in abaqus?

    I am working on a full cervical spine model.in my thesis I have modeled all vertebrae as discrete rigid body.I have tried general contact option to define interaction between vertebrae but when I do analysis because of large deformation two vertebrae penetrate each other.

    any suggestion to define proper contact without any penetration problem??

  • Jason Marion added an answer in Statistical Testing:
    How do i asses interactions between VD levels and smoking and what is the statistical test to do in case-control study?

    how to asses interactions between VD levels and smoking and what is the statistical test to do in case-control study?

    Jason Marion

    The sig. is related to the Wald statistic, and  based upon what the significance tells us, it is likely that the interaction term is significant (p < 0.05). I'm not sure of the commands in SPSS, but the next step would be to see if the model deviance changes significantly between the two-term model and the model with the the interaction term. If the deviance of the models are significantly different, than interaction is presumed to be present. The test between the model deviances is called the likelihood ratio test. (Since the interaction term is significant, it is very possible that the likelihood ratio test comparing the deviance values of the two models (model without interaction versus model with the interaction term) will be significant.   *I did find a very helpful set of Powerpoint slides as a pdf online that provides instructions here. These methods from the slideshow appear to me as being the same as the recommended methods from Levy and Lemeshow's Applied Logistic Regression.   (Slides 42 to 49 should be quite helpful) http://core.ecu.edu/ofe/StatisticsResearch/logistic%20regression%20analysis.pdf