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  • Naveen Malvade asked a question in Texture:
    How CCM(color co-occurrence matrix) texture features are different from GLCM (Gery level dependency matrix) texture features?

    if possible, help me with the matlab code... Thanks in advance......

  • What is level density and it's parameter ? please explai me....

    nuclear physics

  • Coen Maas added an answer in Ficoll:
    PRP (Platelet-rich-plasma) isolation protocol?


    Hopefully, someone can please help me out with my misunderstandings surrounding prp. I have been told that the standard protocol for prp Iisolation from whole blood is 160xG for 15 minutes. This is easy enough, however what I am unclear on is which layer to take! I seems easy enough, but I keep seing pictured and videos of only three layers, then some with more than three layers. The last time I asked about prp isolation, someone gave me the same protocol and said to aspirate the supernatant, being careful not to extract the white blood cells.

    Please let me provide some pictures and you tell me which will be the product of the protocol 160xG for 15minutes no ficoll just 30ml's of whole blood.

    Picture 1:


    Picture 2:


    Picture 3:


    Which one can I expect and which layer do I aspirate? 

    Coen Maas · University Medical Center Utrecht

    The upper part of liquid (yellowish, a bit cloudy) contains plasma and platelets after 15 min 160xG. I am pretty sure that your centrifugation protocol is correct (several of the Synapse bosses/advisors with platelet experience originate from our lab ;). 

  • Abul KALAM Azad added an answer in Copolymerization:
    How can I confirm that a copolymer formed between two monomers which reacted ?

    We need to confirm that a co-polymer is formed and the monomers are reacted.   it is not a simple blend of two monomers.

    Abul KALAM Azad · Jubail Industrial College

    Better you can go for XRD - for compatabilty & crystallinity of two polymers and SEM/TEM for the dispersion.

  • Ndubuisi SAMUEL Machebe added an answer in HEPES:
    Hello, I am trying Handmade Cloning (HMC) in porcine. How can I make the oocytes stable in microdrops of medium for splitting with microblade?

    I find it difficult to split oocytes in medium (hepes buffered T199 + 20% FBS) because the oocytes are usually not stable in the microdrops for efficient splitting during HMC. Is there any better protocol for making the oocytes stable/attached to the base of microdrop during splitting? Thank you all.

    Ndubuisi SAMUEL Machebe · Kinki University

    Dear Pavel,

    Thank you for your response. Actually I meant splitting a metaphase 11 oocyte after in vitro maturation.  According to Gábor Vajta who developed the technique of hand made cloning, the method involves cutting eggs from sows’ ovaries into two halves under an ordinary microscope. The halves with cell nuclei are discarded, leaving half, empty eggs. A cell (e.g. somatic cells) from the mother sow which is to be cloned is first brought together with one empty half, fused and activated by electrical or chemical method. The eggs are then put into an incubator where they develop into blastocyst, which then are implanted into the sow’s uterus (

  • We are looking for a mutual cooperation with a professor of a university inthe US or Europe. Are you interested?

    I am research engineer and team leader of 20 master students at the combustion and heat transfer lab of Iran university of science and technology which is a leading university in Iran. I am looking for a mutual cooperation with a professor of a university in Europe or US for publishing papers in the field of combustion of metallic dust cloud like iron, aluminum or etc. If you have interest in publishing papers and working remotely with our group, please contact me to expand our experience together.

    E-mail: alireza.poorfar@gmail.com

    Thank You

    Alireza Khoeini Poorfar · Shahrood University of Technology

    Thank you professor Mnasri, i am very  grateful for your opinion regarding our works.

  • Luis Garzón added an answer in Social Capital:
    Was there value in the social capital provided by friendly societies in the nineteenth century?

    I am writing my thesis on friendly societies in nineteenth-century Victoria, Australia.

    F S are recognised in the fields of mutuality, respectability, thrift, etc. but their role in civil society requires exploration and in particular answering the question concerning their value/contribution to the social capital of the day.

    Any references or comments?

    Luis Garzón · Universidad de Burgos

    Dear Roland,

    You may find this book on mutuality societies and mgration in turn-of-the century Argentina interesting and relevant to your research:

    Moya, Jose C. (1998) Cousins and strangers: Spanish immigrants in Buenos Aires (1850-1930) , University of California Press

    The book covers the same period than your research and I think you may find similarities between the Argentinean experience and Australia.

    I hope that it helps.

  • Mikhail Ivanchenko added an answer in Real Estate:
    Can anyone suggest scale to measure strategic e-marketing orientation of company?

    I am looking for scale to use to measure strategic e-marketing orientation of company (primary interested in real estate agencies).

    Mikhail Ivanchenko · Lancaster University

    Hello! Maybe you can use percentage of transactions made by e-commerce channel (or its value) vs traditional channels? Also taking into account the growth rate of such transactions.

  • Wei Lu added an answer in FIB:
    How can I polish or etch a silca crystal up to 10 micron?

    I want to see the damage created by laser using tight focusing inside sio2, for this I need to etch it or polish it up 5~10 micron. Can someone give suggestions on how to do this. FIB is one method but it is quite expensive. Is there any other inexpensive method?

    Wei Lu · The Hong Kong Polytechnic University

    Just polishing by using small particle size diamond paper with the help of Gatan grinder can reach 10 um.


  • How can I quantify the thermal dissipated energy during an SHPB impact test?

    During impact in SHPB tests, an increase in temperature was observed. The dissipated energy affects the viscoelastic behavior of composites especially when the released temperature attains the Tg of the matrix. Does anyone know any high speed infrared detector (camera) which is able to monitor temperature dissipation during impact tests or quantified the dissipated energy due to damage?

    Your help will be very appreciated.

    Sivaprasad Katakam · National Institute of Technology Tiruchirappalli

    Depends on material also

  • Ievgen Lebeda added an answer in Agarose:
    Is Low melting point agarose and agarose having low EEO same?

    Can I use agarose having low EEO instead of LMPA in comet assay?Will it give positive results?

    Ievgen Lebeda · University of South Bohemia in České Budějovice

    Dear Neethu Kannan,
    I believe you can use EEO instead of LAMPS in comet assay. Theoretically it should increase accuracy of obtained results, but I doubt you will be able to see any substantial improvements. In case you find change to EEO helpful I would appreciate you to share your experience.

  • Irfan Arif added an answer in Plasmid Isolation:
    How can I differentiate large size plasmids from genomic DNA ?

    I have a wild type bacteria culture and want to check the presence of plasmids in it. I followed the normal plasmid isolation procedure and got a small pellet. In gel electrophoresis a lower intensity band also visualized. The problem is its size is similar to the genomic DNA when they run parallay on the same gel. Gel was 0.7% agarose gel in 0.5x TBE buffer. I did restriction digestion with Not1, BamH1, Hind111. but could not resolve visualize clear bands on the gel. 

    Irfan Arif · University of Groningen

    Plasmids will give you discrete bands on the gel while genomic DNA will give a smear upon restriction digestion.

    If you are getting smears, then most probably its the genomic DNA.

  • What door colors are best to use in an ED room for psychiatric/mental health?

    I have read studies that discuss mood and color in psychiatric settings, but often the study is of a person and the color which does not take into account the many other variables experienced by someone in the emergency department.  There are studies of other rooms, such as used during therapy or in the general milieu.

    I'm looking specifically for door color since our rooms are and will always be laboratory white.  I'm thinking that a great study would be to have at least two rooms with different colored doors and see which one the person (in acute psychiatric distress) chooses indicating a perception of safety.

    Béatrice Marianne Ewalds-Kvist · Stockholm University

    Dear Michael,

    Popular symbolism:

    Currently the most popular decorating color, green symbolizes nature. It is the easiest color on the eye and can improve vision. It is a calming, refreshing color. People waiting to appear on TV sit in "green rooms" to relax. Hospitals often use green because it relaxes patients. Brides in the Middle Ages wore green to symbolize fertility. Dark green is masculine, conservative, and implies wealth. However, seamstresses often refuse to use green thread on the eve of a fashion show for fear it will bring bad luck.

    Solid, reliable brown is the color of earth and is abundant in nature. Light brown implies genuineness while dark brown is similar to wood or leather. Brown can also be sad and wistful. Men are more apt to say brown is one of their favorite colors."

    Read more: http://www.infoplease.com/spot/colors1.html#ixzz3NHlGDnvv

    I would suggest green and brown. Green is traditionally associated with medicine, The serpent in the Bible to which people should look for heeling was green. Brown is for some persons boring but thrustworty color. With shades of brown reflecting a neutral earthy milieu you are bound to succeed in interior decoration.

    The degree of color saturation of these colors should be the same on both doors.

  • Mukhtaj Khan added an answer in Configuration:
    How do I set maximum and minimum velocity value in a PSO algorithm?

    I am using PSO algorithm to search optimum value for parameters within range. I have 5 parameters such as: x0, x1, x2, x3, x4, and x5. Each parameter has own range.

     x0 = [10,320]


     x2= [1, 16]

     x3= [1,4]

     x4 =[1,3]

     x5 = [150,230]

    In program, I am setting the lower and upper position as:

    X0-min = 10;

    X0-max= 320

    Similar for the other parameters (x1,x2.....).

    As, in PSO the particle position is changing based on velocity. I am confused on configuring a value for the velocity.  How I can control velocity of a particle. I mean how to set limits of the velocity for each parameter? Should I use similar value for v0-min and v0-max as I used for the x0-min and x0-max?  

    Mukhtaj Khan · Brunel University

    Thank you very much all of you, Stephen, Pramond and C.K. Dimon for your valuable suggestions. I have applied the suggestion of Dimon and I think it is working for me. Many thanks again.

    Happy New Year 2015

    Best regards,

  • Keith Penrod added an answer in Topological Groups:
    How can we define a group homomorphism by a single element?

    I am looking for a homomorphism in a topological group that which uses by a single and fixed point. I mean for a fixed element of G, how we can construct a group homomorphism. For a fixed g, I tried the definition x \to gx, by this is not a group homomorphism. How we can do it?

    We can add some hypothesis to G, like being locally compact or connected.

    Keith Penrod · Morehouse College

    Oh, never mind.  I was thinking about the map x\to x^{-1}.  No, that's not a homomorphism.  At least, not in general.

  • Is it possible to neutralize all the positive resistances in a circuit by an equivalent negative resistance?

    I have asked this question with two purposes - first, at the request of Barrie Gilbert to terminate the irrelevant discussions in the question below...


    ... and second, to answer the question of Erik Lindberg asked at the end of this discussion.

    In the discussed arrangement (an RC circuit with various leakages), there are three resistances in parallel - R, Rc and Rv, and the equivalent resistance is Re = R||Rc||Rv. My idea is to connect a variable (N-shaped) negative resistor in parallel to Re and begin adjusting its resistance RN. Depending on its value, it will "eat" some part of Re and it will dissapear (become infinite):

    1. RN = Rv (Rv is neutralized) or RN = Rc (Rc is neutralized)

    2. RN = Rc||Rv (both Rc and Rv are neutralized)

    3. RN = Rc||Rv||R (all the positive resistances are neutralized)

    In case 2 (a load canceller), I think we should obtain a perfect exponential shape... and this should solve the leakage problem.

    The next my idea was that if we continue decreasing this "destroying" negative resistance beyond this point of exact leakage neutralization, it will begin "eating" a part of the positive resistance of the "useful" resistor R... and finally, it will destroy all the resistance R. This means that the resistor R as though already has an infinite resistance... and behaves as an ideal current source... Actually, this is the idea of the Howland current source and its special case here - Deboo integrator. But while in the classic Deboo integrator the negative resistor (INIC) neutralizes only the positive resistance R, here it neutralizes all the resistances in parallel (the useful R and harmful leakages).

    So, my question now is, "What happens if we try to neutralize all the positive resistances by an equivalent negative resistance (case 3)?"

    My doubt is that, as a result of this 100% neutralization, this circuit will become unstable, and if the negative resistance begins dominating over the equivalent positive resistance, the effective resistance (the result of the neutralization) would become fully negative. And here, I suppose, the voltage across the capacitor will begin self-increasing in an avalanche like manner...

    The same problem exists in the Wien bridge oscillator... and it is solved there by applying a non-linear negative feedback in the INIC... Maybe it is possible to keep the circuit stable in a similar way?

    Cyril Mechkov · Technical University of Sofia

    Vasile, I have added a circuit diagram (especially for you:)

    Christian, I am afraid that the problem here is not the zero but sooner the infinite resistance...

  • Brijesh B. Mehta added an answer in MapReduce:
    Has anybody worked on iterative MapReduce algorithms/functions? If yes, in context with which use case, please provide and how?

    MapReduce, Large Data Analysis

    Brijesh B. Mehta · Sardar Vallabhbhai National Institute of Technology

    if you have sufficient memory and not working on too large dataset then you may try spark "https://spark.apache.org/" which provides in memory operation for faster iterative mapreduce function.

    you may also find survey of various big data analytics platform from this paper "http://www.journalofbigdata.com/content/2/1/8"

  • Tova Schlesinger asked a question in Scholar:
    How do you "Art historian" scholars search,find and share information?

    How do you "Art historian" scholars search,find and share information for your search

  • Sivaprasad Katakam added an answer in Acetic Acid:
    What can we do for increasing the corrosion resistance of hastelloy B2 weldments?

    We want to protect a hastelloy B2 reactor for production of acetic acid against corrosion. It was made by welding and in certain periods of time the weldments are corroded severly because of increasing the concentration of HI (hydrogen Iodine) in the vessel. We want to perform a protective treatment for the weldments. In some literature quenching of the weldment from about 1100 'C is recommended but it is not practical because of the large size of the vessel. What can we do? Best regards. M. Khorasanian. 

    Sivaprasad Katakam · National Institute of Technology Tiruchirappalli

    A process like electrolytic plasma processing can help you a lot. But as you said size may become constraint for you.

  • How can we prepare nano-crystals ?

    We know that we can prepare nano-materials by sol-gel, co-precipitation methods. However, when we prepare nano-materials with these methods it often results in amorphous materials. In this situation, how can we prepare nano-crystals with a simpler method?

    Romuald Intartaglia · Italian Institute of Technology (IIT)

    Hello Venkatathri, a simple route to prepare and conjugate a variety of nanostructures (semiconductor, metallic, bimetallic, ceramics etc...) in a scalable and clean manner is laser ablation in liquid. Mainly the method consist to ablate a solid target placed in liquid environment (deionized water, aqueous solution of biomolecules, monomeres,...). The resulting colloidal solution is ligand free i.e. no hazardous chemicals at the NPs surface. Another aspect is that the method fulfill the twelve principles of green chemistry. I can give some suggestions if you are interested by this method.

  • César A. Cárdenas added an answer in Sample Size:
    How can we calculate sample size for ecological studies?

    I want to estimate association between ambient air pollution and delivery out cam in ecologic study. How can we calculate sample size in this study?

    César A. Cárdenas · Instituto Antartico Chileno

    there are couple of calculatorts available. For example




    If you want to perform it in R http://www.statmethods.net/stats/power.html

  • Is there any work about the use of statistic survival models (for example, hazard Cox) in health sciences ?

    I'm looking for a method to evaluate the vitality of the research group in the field of health sciences (with exception of the estimated mortality). Does anyone know where I can find works that use the statistical method of survival in the natural sciences.

    Małgorzata Kałwa · University of Physical Education in Wrocław, Poland

    Thank you very much for your help. I have a bit of a problem using the method of Kaplan -Meier, because its methodology is the assumption of mortality (data decrease). And I want to make statistics attendance of traning's health , where people come back. I do not know how to do it and I am looking for articles that can help me to solve this task.
    Thank you for the links.

    Thank you for the tip, I'll try to take advantage of this assumption.

    I greet

  • Should the effluent of secondary treatment of pulp and paper plant be reused for irrigation?

    A free chlorine plant of pulp and paper will be installed near Orinoco River and the effluent has to be reuse because it not will be discharge to the river, the concentration of BOD wil low but the COD will be around 800 mg/L and the real color will be high too. The secondary treatment will be an activated sludge process selector type.

    Elisavet Amanatidou · Technological Educational Institute of Western Macedonia

    I agree with Ms Simona Frone. A tertiary treatment may be necessary. Nevertheless, it must be an environmental impact assessment in accordance with country’s legislation concerning the limits for surface disposal of wastewater.

  • How to find the homogenity and percentage of reinforcement present in the Aluminium Silicon Carbide metal matrix composite ?

    Homogeneity and Percentage of Reinforcement present in Al-SiC metal matrix composite.

    Sivaprasad Katakam · National Institute of Technology Tiruchirappalli

    As it is told by Alexander, computer tomography is highly accurate. If you want a rough and comparative values, simple microstructure analysis with serial sectioning can help you. % can be calculated using XRD also.

  • Sheng Yun Wu added an answer in Ferrites:
    What is the effect of domain wall motion on Magnetization of Ferrites?

    I'm wondering whether domain walls hinder, increase or decrease magnetization?

    Sheng Yun Wu · National Dong Hwa University

    Domain wall motion means it's rotation under applied magnetic field, you can try to measure hysteresis loop and analyze using a single domain model of Stoner equation.

  • What is the biggest scientific coincidence that you know?
    For me the two more important are:

    1. The phase transition liquid-solid for the water is that the solid state is less dense.
    2. The dielectric screening in metals is such that the Coulomb interaction among the electrons falls at a distance of the Bohr radius.

    The first one has many important applications as the one of allowing the live in rivers during winter or so on. On the other hand, there are also very interesting electric and thermodynamic phase transitions for this material

    The second, thanks to have a so local electric interaction it allows to have almost free electrons at quite high electronic density in matter and therefore to apply theories so useful as the bands in solids. Over all in metals
    Daniel Baldomir · University of Santiago de Compostela

    Dear Robin,

    Is the Kerr metric the good one for describing of the black hole? or what one? Could a black hole be borning at these moments in anywhere of the universe? One thing seems to be quite logic: gravitation is only attractive, therefore. as much bigger a mass is, more likely can grow too. What do you think about?

  • Vijaya Kumar added an answer in Antioxidants:
    Is there any plant which does not have antioxidant activity?

    Today the terminology "Rich in antioxidants" has been easily equated in the public mind with "beneficial". Are all plants rich in such antioxidants or here also exception do exists? If the exception exits what are the plants which do not have antioxidants.

    Thanking you.

    Vijaya Kumar · Vaagdevi College of Pharmacy

    I also agreed plant in the universe possess rich antioxidant. In future characteristic antioxidant levels in different plant in different climatic environment.

  • Maryam Mirdamadi asked a question in Parasites:
    Does anyone know about pangasius family and their parasites?

    relative to ancylodiscoides, trichodinoides and ichthyophtrius multiphilis.


  • Where to find the source code in c for Embedded Systems?


    Currently I am working in software testing. I need some large source code of embedded system for testing purpose like: elevator system, patient monitoring system etc in c. I have googled for source code but it only showed small project.

    Can anyone help me finding source code in c? 

    Jonathan Schattke · Missouri University of Science and Technology

    Usually, such code is proprietary, so you won't see it publicly available.
    The scope of public embedded systems is, as you note, very circumscribed.