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  • Faiza Bukenya asked a question in Ground Truth:
    Which software is good at obtaining ground truth for the 3D heart vessels?

    Hi. Iam segmenting  heart vessels. i need ground truth data . Which software is good at obtaining ground truth for the 3D heart vessels?

  • Paul Dirkes added an answer in Dentistry:
    Do you tell the patients to wear retainers for life?

    Do you think patients will accept it?

    Paul Dirkes

    1 or 2 years and sometimes a lingual bonded retainer to hold teeth 7 and 10 if they were mesially rotated.

  • Eric Ariel L. Salas added an answer in Landsat:
    How to convert the DN values to reflectance?

    Can Some one help me in converting DN values to reflectance for Landsat 4 & Landsat 5 Images using ERDAS or TerrSet or ENVI. I highly appreciate any support.

    Eric Ariel L. Salas

    In addition to what James wrote, you should read the paper "Revised Landsat-5 TM Radiometric Calibration Procedures and Postcalibration Dynamic Ranges" that details the conversion process.  Focus on sections 3 and 4 of the paper.

    Good luck!

  • Dhananjay Pandey asked a question in Bacterial Cell Culture:
    How to measure folic acid/Folate content in the bacterial culture using spectrophotometer?

    Want to measure folic acid produced by bacteria, Is there any specific wavelength fixed for folic acid detection.

  • Waldemar Koczkodaj added an answer in XLSTAT:
    I m experiencing problems in plotting vector lines from origin in PCA analysis. How vector biplots can be plotted in PCA analysis using XLSTAT?

    Vector biplots for PCA. 

    Waldemar Koczkodaj

    gnuplot is for plotting...

    how you get results is your bsn

    gnuplot is a part of MANY MANY system including gnumeric and Maxima

    There are also many GUI for gnuplot

    For PCA analysis, the best is R system which uses gnuplot2 (variation).

    For R system (has a package with my name), you use RStudio or similar GUI (without it, it is useless).

    You may contact me if you nail R+Rstudio :) and I can give you something leading to a publication (if not, good luck :). Same goes for anybody else.

    Pls upvote if useful...

  • Richard Traub added an answer in Entropy:
    Why should the reciprocal Fibonacci appear in the approximation of a process?

    I had the following:

    1/1 *a + 1/1 *b + 1/2 *c + 1/3 *d + 1/5 * e + ..

    which correlated strongly (0.96) with a huge statistical data of a process (a, b, c etc. are calculated following a semantic model).

    Fibonacci series ... spirals, Golden ratio appear in nature, several works on this.

    I will be very thankful to receive, dear colleagues, suggestions about processes in physics, biology, evolution, entropy, information... that have shown such a Fibonacci "reciprocal" behavior.

    Richard Traub

    Dear Velina,

    "how precisely is this related to real processes, information, entropy, systems. How these faster convergent series can suggest me this? Becouse they are alternate perhaps? Physics, waves...Why should the reciprocal Fibonacci appear in the approximation of a process? "

    Although neither of the authors below appears specifically (to my limited awareness) to discuss Fibonacci manifestations  I have a strong gut feeling that the underpinning explanations are to be sought  in the perspectives of Synergetics, developed by Hermann Haken (from ideas inspired by laser theory, non-equilibrium thermodynamics and Schrödinger's "order based on order" proposal for the organization of living matter), and of Scott Kelso's Dynamic Patterns theory, which extends synergetics thinking to account for the brain's capacity to organize and co-ordinate goal-related motor behaviour.

    For literature by Haken, Kelso (1995, op. cit. below) recommends:

    The Science of Structure: Synergetics. New York:Van Nostrand Reinhold, 1984

    Synergetics, an Introduction: Nonequilibrium Phase Transitions and Self-Organization in Physics, Chemistry, and Biology, 3rd rev. enl. ed. New York: Springer-Verlag, 1983.

    Advanced Synergetics: Instability Hierarchies of Self-Organizing Systems and Devices. New York: Springer-Verlag, 1993 

    For the contents of the last:http://tocs.ulb.tu-darmstadt.de/12242607X.pdf

    For Kelso:

    Kelso, J.A. Scott (1995): Dynamic Patterns: The self-organization of brain and behavior , MIT Press (Preview - http://www.amazon.co.uk/Dynamic-Patterns-Self-Organization-Behavior-Adaptive/dp/0262611317/ref=sr_1_1?s=books&ie=UTF8&qid=1454938777&sr=1-1&keywords=9780262611312

    which I've been reading over recent months. Perhaps you also might find the following chapter, co-authored by Kelso, stimulating, and perhaps offering some pointers:

    Kugler, P. N., Kelso, J. S., & Turvey, M. T. (1982). On the control and coordination of naturally developing systems. The development of movement control and coordination, 5, 78. http://www.haskins.yale.edu/Reprints/HL0378.pdf  

    Warmest wishes, Richard.

  • Diarmuid Hayes added an answer in Applied Science:
    I have a colleague who is looking for a scientific dictionary spell check for microsoft word and the process to upload it? He is using Windows 7.
    I am wondering is there such an add-on to word?
    Diarmuid Hayes

    Thanks very much!

    Was doing a quick test to check if it worked, and I found it (wncensus) contains Tiliacea, tiliaceum and tiliaceus, but not tilia/Tilia! Oh well =)

    Thanks again

  • Albana Mihali asked a question in Lentivirus:
    Does anyone have experience transducing mouse Treg/ nTreg with GFP- lentivirus?

    Does anyone have any pointers or a protocol to optimize transduction into my Treg/nTreg cells?  

    • I stimulated my cells overnight with:

    Anti CD3- 2 µg/ml
    Anti CD28 2 µg/ml
    IL2-200 ng/ml

    • Used polybrene in a concentration of 8 mg/ml
    • Virus Titer 6x1010/ 1 µl per 100k cells

    I do not have a good expression of GFP. Any pointers will be greatly appreciated. Thanks!


  • Ann Atzberger added an answer in Multicolor Flow Cytometry:
    In flow cytometry compensation using beads/cells why is a very strong single staining of your compensation control of benefit?
    I've used beads and cells side by side to do my compensation for a multicolor staining on PBMCs. Here I experienced that the staining (esp. with PE-CD594) on my single stained beads was so strong that I had to lower the voltage quite substantially in order to gate for the positive beads. In a different experiment, using PBMCs, the signal for this particular colour was much weaker and therefore I set the voltage much higher.
    Analysing the data it turned out that the lower voltage lead to a much better separation of my populations, which is nice.
    My confusion now is I read before that a very strong staining of the compensation control is desirable and usually beads are better than cells. What did I do not understand? Why is a very strong single staining of your compensation control of benefit?
    Some advice would be much appreciated. Thank you.
    Ann Atzberger

    Just remember it is the sample that is important. In an initial set-up single colour cell controls are run, compensated and the impact on the sample is reviewed, settings may need optimizing etc. Once this has been done to satisfaction the beads are then run on the settings that you judge to be optimal for your SAMPLE. If beads go offscale you could try adding less antibody. The beads are a control that help to maintain consistency and can help to detect issues with antibodies etc.

  • Pradeep Kumar asked a question in Normalization:
    Normalized cross correlation is preferred?

    When normalized cross correlation should be preferred to find time delay

  • Petteri Vainikka added an answer in DL-POLY:
    Does anyone know how to take into account the parallel piped boundary conditions when calculating MSD?

    Ive simulated benzene inside MCM-41 using DL_Poly classic 1.9 and wish to calculate the mean square displacement of the benzene atoms however I run into problems with the parallelepiped boundary conditions used. Large jumps are seen in the MSD corresponding to when the benzene leaves the box and comes back in the other side. If it were a cubic system I could just remove the length of the unit cell but as its a parallelepiped this doesnt work. I've tried using the java GUI but this crashes due to the large time simulated (10ns)

    Does anyone know how to take into account the parallelepiped boundary conditions?

  • Vladimir Kolyadko added an answer in Platelet Activation:
    What is the best method to isolate platelet population from blood without activating them?

    Platelets a very sensitive to many condition. So, want to isolate the population of platelets from whole blood but without activating them.

    Vladimir Kolyadko

    I propose to prepare platelets by the gel-filtration procedure instead of centrifugation and reconstitution.

    I studied formation of phosphatidylserine positive (PS+) murine platelets (these marker usually appears upon strong activation). Platelets were gel-filtered and a background level (without activator) of PS+ platelets were less than 2% (from total population). For comparison, Jobe et al. (2006) who prepared mice platelets by centrifugation got the background level up to 5%.

    I would recommend the following papers: PMID: 6800196; 3113155; 2945282

  • Craig Laverick asked a question in Seafaring:
    Can you help with ISM Code research?

    I am currently undertaking research into the implementation of the International Safety Mangement (ISM) Code by shipping companies and seafarers, and its enforcement, as part of a PhD project at the University of Central Lancashire, with particular focus on whether corporate manslaughter legislation be used to enforce better compliance.

    I am looking for volunteers to complete a short questionnaire as part of my research. The questionnaire is made up of 16 questions and should take no more than 10 minutes to complete. If you are interested in helping with my research project by completing a questionnaire, or if you require further information on the project, please email me at claverick@uclan.ac.uk.

    Craig Laverick

    PhD Candidate

    Lancashire Law School

    University of Central Lancashire

  • Pharmacist Pharmacist added an answer in Emulsions:
    Hi, is it right to sonicate the formulation at 70 % for 4 minutes to form nanoparticles or not?

    I am preparing nanoparticles by w/o/w double emulsion method.Firstly I am sonicating w/o emulsion at 70 % amplitude for 2 minutes by using sonics vibracell ultrasonic processor 500 W, 20 kHz and then again sonicating the w/o/w emulsion for 2 minutes at 70 % amplitude using sonics vibracell ultrasonic processor 500 W, 20 kHz. Is it right? 

    Pharmacist Pharmacist

    Roni thank you, at what amplitude you sonicated your formulation and for how much time? 

  • Ilia Korjoukov added an answer in Eye-Tracker:
    How to Save Time (mm:ss.ss) on a Video to Analyse Emotions?

    We've done experiments with webcam videos showing the face of a person. The videos are part of an eye tracker software. We use the same videos to analyse the emotional expressions on the face.
    Because the SMI software BeGaze cuts away parts of the videos (e.g. loading times of stimuli) the videos and its timelines (shown in BeGaze) are shorter than the original videos. The consequence is that it's very diffcult to sychronize the data of the eye tracker and the emotion data.

    To resolve this problem I'd like to save (postprocessing) the time / a timestamp on the video (format: .mkv) that remains visible on the video if used in BeGaze (i.e. the time / timestamp is part of the image).

    How can I save the time (mm:ss.ss) permanently on a .mkv video?

    Ilia Korjoukov

    Hi Egon,

    Our software, EventIDE (www.okazolab.com) can carry this task easily. You may have timestamps of every video frame and SMI tracker sample recorded with ms precision. Moreover, you can also record a participant's facial expression in parallel to stimuli and eye-tracking, with synchronization markers in a video file.

    Let me know, if you need a demo for such task.

  • Pradeep Kumar asked a question in Correlation:
    Time Delay finding?

    I am using cross correlation to find time delay in sinusoidal function. It works fine with small dealy.However, with relatively large delay it does not give accurate answer. Please aclrify my doubt.

  • Noureddine Soltani added an answer in Fixatives:
    I am doing micro nucleus assay by using acetocarmine, but still i am not getting any result. what should i do?

    i am following protocol is ---

    root tip was fixed in fixative for 3 hour at 4-6 degree Celsius then hydrolysed with 1N HCl for 15 min and finally stain with acetocarmine for 2 to 5 min and also try for 24 hr.

    where i was doing wrong? pls guide me

    Noureddine Soltani

    Sorry I have worked only on animal models !

    Best regards N. Soltani

  • Emile Faye added an answer in Thermal Infrared Imaging:
    Can anyone help me with TIR images of natural landscapes in the tropics?

    Hi there,

    I am looking for any thermal infrared images of natural landscapes (any landscape that do not include non-natural objects, crop fields accepted) taken in the tropics (the closest to the equatorial line) from 0 to 6500 m.a.s.l. under clear sky conditions (no clouds) between 10:00 am and 3:00 pm. I will need the exact location of the picture. Any format that I can read and access temperature data: best is .csv attached with the .tif image in false colours. 



    Emile Faye

    Thanks for you reply, but I am actually looking for TIR images with a resolution of few centimeters /px no more. That is why I cannot use satellite images :)


  • Sudipta Ramola asked a question in Lead:
    How to make 50 mg/ kg lead concentration from lead nitrate in soil

    How to make 50 mg/kg lead concentration from lead nitrate in soil.

  • SHAKTI Shrestha asked a question in Statistical Testing:
    How to design a case control study and choose appropriate statistical test for it ?

    Designing a case control study from a registry that can go back retrospectively up to 15 years and using appropriate statistical test in the design.

  • Prof. Shashikant S. Udikeri added an answer in Entomology:
    What are the best ways to rear the orange blossom midge adults in laboratory conditions ?

     What are the best ways to rear the orange blossom midge adults in laboratory conditions ?

    Prof. Shashikant S. Udikeri

    I have not come across any diet for midges. Many drosophila diets have failed to encourage its growth. I usually rear a flowerbud maggot Dasinuera gossypii on live plants.

  • Binal Parekh added an answer:
    What are the current simulators for energy efficiency in Cloud data centers?
    The simulators are currently been used for energy efficiency in cloud computing research.
    Binal Parekh

    how to combine cloudsim and cloudanalyst for power consumption in cloud data center

  • Bart Dewulf added an answer in Econometrics:
    Any recommended techniques for testing causal relations?
    I want to test the causal relationship between a dependent and few independent financial variables. I am not sure whether my data is linearly related so I cannot apply linear regression with confidence. What other techniques can I explore? How to proceed?
  • Vladimir Rasvan added an answer in Nonlinear Control:
    Can anyone suggest good reference for the time optimal nonlinear control?

    I am looking for a reference for a time optimal control for nonlinear system, preferably with some applied examples instead of just theory..

    Vladimir Rasvan

    Another useful book:

    "Foundations of Optimal Control" by E. B. Lee and Lawrence Markus 

  • Mohammed Sahal asked a question in Metallography:
    Do people rely more on the details from the manufacturing , processing and written details to judge and evaluate a microstructure ?

    I mean like whether people rely too much on the details provided (MTC , Envronmental conditions etc) rather than getting the information from the microstructure itself , How much details a material microstructure can provide without any prior knowledge supplied on it . Whether is it possible judge correctly if the material microstructure is supplied alone and no other details about the part,component etc etc is provided . I mainly details acquired through  conventional optical metallography for metallic microstructure.It is often that even experienced metallurgist misinterpret microstructures if no details on it is provided ...

  • Rafik Karaman added an answer in Eukaryotic Cells:
    How can I take out eukaryotic cells from solution when organic substances are sticking to filter?

    I have a solution of methanol with solvated extracellar components made by a yeast I'm growing. I'm trying to take out any stray cells that may have made their way into my solution . I just tried using a .45 nm pore filter but my solution can't even make it through other than a ml or 2.

    I am assuming this is because the solutes I am trying to isolate are sticking to the filter or each other.

    Thank you for your help. 

    Rafik Karaman

    'Dear Erin,

    You may use Buchner Filter Paper in which a water vacuum is assisting in the filtration.


  • Yifu/Yi-Fu Fang added an answer in Plasmids:
    Short Library Cloning-What is the best method?

    Hi all

    I have a ~80bp randomized library(with 15bp constant region on each side). My goal is to clone this into a vector (p15a ori plasmid  ~5kb). I am just wondering what would be the best method to get as many colonies as possible. I have been thinking about golden gate. I do have BsaI sites inbeded. The only question for that is the details. What should the insert and vector ratio (two BsaI sites are pretty different and 3 out of 4 bp are not matching, is concatemer a concern?)? Also should i get NEB golden gate cloning kit or should i just make my own and add loads of ligase and BsaI? Also should I predigest PCR of my vector and dephosphorylate it before the golden gate (I know it can be digested in the golden gate mix, I am just wondering if that will minimize the background and thus increase the positive colonies numbers) If anyone has any suggestion or ideas, that is much appreciated!

    Yifu/Yi-Fu Fang

    If you use PCR products for cloning, it is necessary to phosphorylate the inserts and dephosphorylate the Vector before ligation in order to maximize the successful cloning and minimize the background.

  • Lidia Fotia added an answer in Bibliometrics:
    Can anyone provide a proffessional methodology to get bibliometric studies and compare journals?

    I'm trying a bibliometric investigation.

    Lidia Fotia

    This article is very interesting:

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: In this paper we present the results of a study on the potentialities of “bibliometric” (publication and citation) data as tools for university research policy. In this study bibliometric indicators were calculated for all research groups in the Faculty of Medicine and the Faculty of Mathematics and Natural Sciences at the University of Leiden. Bibliometric results were discussed with a number of researchers from the two faculties involved.Our main conclusion is that the use of bibliometric data for evaluation purposes carries a number of problems, both with respect to data collection and handling, and with respect to the interpretation of bibliometric results. However, most of these problems can be overcome. When used properly, bibliometric indicators can provide a “monitoring device” for university research-management and science policy. They enable research policy-makers to ask relevant questions of researchers on their scientific performance, in order to find explanations of the bibliometric results in terms of factors relevant to policy.
      Full-text · Article · Feb 1985 · Research Policy
  • Aly R Abdel-Moemin added an answer in Glycemic Index:
    What parameters and variables influences glycemic index in pasta making processes?

    Could someone suggests me some very interesting scientific papers about relationship between technological properties of durum wheat semolina and Glycemic index? And what variables influence glycemic index in pasta making processes?

    Aly R Abdel-Moemin

    Dear Dr Giuseppe, 

    Research is still working but slowly? until this moment no research done for the effect of cold pasta! However,  I have attached some documents may help.


    Also this book whole grains and health page 299. 


    Best regards