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  • Is there any technique to reconstruct a hash chain if some records have been removed?

    For example there is linked chain of hashes of a document. some of consecutive hashes are deleted how to recover or reconstruct the chain.

    Idrees Ahmed · COMSATS Institute of Information Technology

    I was asking for example; there is a chain


    an adversary delete "Hash3.....Hash4......Hash5......Hash6" can we recover the the chain by any mean?

  • Judocus Borm added an answer in Blood Cells:
    What receptor is specifically expressed on platelets and not other blood's cell types?

    There are some receptors expressed on platelets that are shared with other cell types. I would like to know what receptor(s) is only expressed on platelets?

    Judocus Borm · Reinier de Graaf Groep

    For unrelated reasons I recently checked out all of  the CD xxx series. 

    Except for CD110 and CD42 you kan skip all of the CD-series because of cross-reactivity with other cell-types.  Saves some work.

    Quite a few have multiple names. Several of the toll like receptors hav a CD number too.

  • Mojgan Mirzaei asked a question in Model Evaluation:
    Introduction a model?

    hi, i am looking for a model to evaluate the fate of pollutants in soil or water. do you know any model for this purpose?and what information is required for this topic?

  • Is fertilization financially justified midrotation in forest plantations?

    It would be interesting to know if the cost of fertilizer is reset at the end of turn for the additional increase wood generated fertilizer. Always assuming that the fertilizer is applied after the last thinning and trees that will be part of clearcutting.

    Miguel ÁNGEL López-López · Colegio de Postgraduados

    Hi, Rodolfo.

    Financial profitability of fertilization in forest plantation has to do mainly with the limitation degree of the nutrients you apply.  If you apply the nutrients that are limiting growth in your site, then it is highly probable that the operation will be profitable.  If you apply non-limiting nutrients, then you can even decrease tree growth. Moreover, if any other factor such as inter or intraspecific competition is taking place in your plantation, financial profitability of fertilizer application will be little likely.  In such case, you should correct that situation first (i.e. thinning).  


  • Lambert Zijp added an answer in Texture Analysis:
    What is the best method for capturing the variation of texture patterns within an image space?

    I am currently trying to distinguish between an image's foreground and its background using texture of sub-image regions. I have use Law's texture energy calculation but i am not satisfied  am not satisfied with the result, I need better method for this purpose. 

    Lambert Zijp · Netherlands Cancer Institute

    Could you post a sample image?

  • What are the polymer which can be utilize for making super-hydrophobic surface?

    we are having self-assembled silica particles on glass surfaces. can anyone of you suggest some polymer by which are normally having contact angle 90-100 degree and after coating it will show super-hydrophobic properties. 

    Rinkesh Bhatt · Global Engineering College, Jabalpur

    Dear Nainsi,

    Conducting polymer like Polyaniline(PANI),  Poly diaminonaphthalene (PDAN) or Poly (3,4- ethalenedioxidethiophene) (PEDOT) are some example of hydrophobic materials. They have thermal and optical properties and obtain in film form when forms composite with other polymers shows great mechanical properties. As these composites in film form has positive or negative skewness (AFM analysis) , easily coated or coating takes place. 

  • Andrei Rogoza added an answer in Ceramic Materials:
    How can I modify the surface of C/SiC ceramic material to increase its surface area for joining purpose?

    I want to improve the shear strength of flat on flat joined C/SiC to metal by increasing the surface area. 

    Andrei Rogoza · Irkutsk Institute of Chemistry of the Russian Academy of Sciences

    Hi, Kashif!
    Thanks for votes but it is better to vote in future for successful recommendation. IMHO :-).

    Looking on your micrographs I see that you have different carbon fibers/silicon carbide composite as noted in citation from my previous message (to Igor L. Shabalin). Direct contact of Ti from Ti 6Al-4V  and highly reactive carbon sheets lead to formation of titanium carbide. This is very undesirable interlayer because of brittleness. I attach file where reported about this problem and some solutions. ✌

  • Gian Paolo Sanino added an answer in Jellyfish:
    Can anyone help me to identify this "jelly thing"?

    This "jelly ball" has been saw twice floating in shallow marine waters in Sicily (Mediterranean Sea). Someone suggested that it might be a damaged jelly umbrella but the evident bilateral symmetry suggests that it should not be a jellyfish. Hence the "damaged jellyfish umbrella" seems improbable. It might possibly be part of an organism or even an ooteca (mollusk ooteca?). What's your idea about?

    Gian Paolo Sanino · Centre for Marine Mammals Research LEVIATHAN

    Thanks so much Stefano,

    My sighting was in 1999 in an area where it is common to see Cyanea capillata. I had my sailboat anchored and saw these "balls" appearing around of it, slowly dispersing and getting some stranded in the nearby shore of the small island. It may take me some time to find the videos etc of that time, but here I have a partial picture. The size was about 11x18cm.

    I have been so many years looking for an explanation for these "balls". Thanks again for your support in helping to better understand these cases. And to Luigi that posted his case.

  • Which autophagy related proteins have a short life time in primary human cells?

    Many autophagy related proteins, like Beclin1, ATG7, etc. have a certain half life time. Which proteins are degraded at a relative high speed (so within 24 hours)? Does anyone tested a certain target (ATG) using western blot or another approach using human primary cells?

    Peter Crauwels · Paul-Ehrlich-Institut

    Indeed, p62/SQSTM1 is a good readout to investigate autophagy activity and autophagy flux, both assays which we established (also using BFLA1, etc.) I was more looking for a protein in the core machinery which could be targeted in human primary cells.

  • Lambert Zijp added an answer in Optic Disk:
    Can anyone help to segment a roughly circular object from gray image ?


    I am working on segment the landmark of retina, one of these landmarks is optic disk, i hardly tried to segment its shape ( roughly circle) from the image but no result i 'v got. so any research can support my with an idea?

    of course i'v used the green channel only from the RGB color space.

    with my thanks.


    Lambert Zijp · Netherlands Cancer Institute

    Could you post a sample image?

  • Can you predict thickness of a deposited nanotube/wire from the no. of moles of metal deposited?

    Electrochemical deposition of metal through the pores of a membrane; active surface area of membrane known, and pore density known.

    Morteza Amjadi · Max Planck Institute for Intelligent Systems, Stuttgart

    We used some theoretical estimations in our previous paper. Might be helpful.


  • Davide Borelli added an answer in Sound Analysis:
    Are there any strong reasons or advantages for using the Delany-Bazley model compared to other empirical models?

    I seeking for best answers and the advantages of using Delany-Bazley empirical model that used to predict sound absorption value, comparing to other models that proposed by Allard-Johnson, Miki or Wilson`s Model. I know its simple and fastest method but i finding more strong reason to compute my results even it out dated method. If attach with some proven research publications are most helpful for me. Even comparison among the models also would help me. Thank you to all.

    Davide Borelli · Università degli Studi di Genova

    I suggest you to read "Sound absorption of porous materials – Accuracy of prediction methods" by Oliva and Hongisto http://www.sciencedirect.com/science/article/pii/S0003682X14001261

    and also "On the modification of Delany and Bazley fomulae" by Kirby http://www.sciencedirect.com/science/article/pii/S0003682X14001261

  • Halima Hami added an answer in Insemination:
    What are the disadvantages in using instrumental insemination in queen bees?

    I would like to explore I.I. on Bee Queens. Is there any risk in facing that technique.

    Thanks in advance for your courtesy in this matter.


    Halima Hami · Ecole Nationale Supérieure Agronomique

    rapide et pas cher mais elle  est très délicate ,avec laquelle on peut maîtriser l’agressivité de l'abeille .

  • In resource block filtered OFDM, how to remove extra phase added to signal by linear filter?

    I am performing filtering on my received OFDM signal. After filtering for my required band I am doing timing sync and CFO estimation. both are working fine. But the problem is when I plot scattered plot constellation points are rotated with some fixed angle  even if i select critical window for FFT also.   Please help me resolve this problem.

    Abdelhalim Zekry · Ain Shams University

    Dear Suresh,

    If all the constellation points of the QAM symbols are retoted by the same angle, the matter is simple. You have only to derotate the symbols with the sane angle of the rotation. Simply multiply the symbol vectors in the polar coordinates by e(-j theta), where theta is the angle of rotation.

    wish you success

  • Could anyone suggest some ideas for trusting the new cloud user in the providers point of view?

    I am interested to know how the cloud providers trust their new cloud users and what are the factors they considered for trusting the new user.

    Robson Eisinger · University of São Paulo

    What Alkhuder said resume what you can do right now to "trust" a user to any given service (Cloud computing included). Just be careful, as said by Mexner when considering e-mail validation, avoid any free service that are not reliable (10 minutes e-mail, for instance). 

    Now, Swant suggested a way to keep that trusting. Indeed, a account can be compromised but not just that, most of those information can be forged, so you can give real information stoled from a target (name, address, credit card and billing information) and give an valid e-mail and phone number, but not related with those information. That way you can answer all the challenges and create a valid account to exploit "anonymously"  at least, for the hacker. Ok, I'm talking about a few cases here, for most of the users this will be enough to avoid any trouble or abuse from them.

    But we must no forget the Pareto Principle, or 80–20 rule: 80% of the effects come from 20% of the causes.

    So behavior profiling is a good idea to improve that trusting. The problem, profiling only works when considering the normal use against any activity that goes out of that! That's why Sawant also suggested decoy techniques! Brilliant! But you need to now your user bases and how to put those decoys to identify any unusual activity. Depending on what you want to observe, honeypots are great! You should also consider an IDS (I'm giving some links regarding IDS on Cloud bellow).

    Trust is something you must earn and keep, it's a continuous process. And I almost forget one important thing: You must follow a police, what you will do when you found a account violating your terms of use? Ban forever after an investigation? Just block it? Inform the authorities? I would say we must rely on the cyber laws, as said by Alkhuder, and that depends according to each region/country. 

    Well, enough for now. 


  • Jason Leung asked a question in Glucose:
    Should NDD (newly detected diabetes) be excluded when I want to find the optimal cut-point of HbA1c to predict prediabetes?

    I would like to find the optimal cut-point of HbA1c to predict prediabetes (using fasting plasma glucose and 2-h plasma glucose) to define. I wonder if the NDD should be kept in the model or excluded. I find if I exclude the NDD, the AUC of HbA1c predicting prediabetes is higher. Thank you.

  • Sergio Palma asked a question in Transformation:
    Are there other methods to induce malignant cell transformation than viral and sh-targeting?

    Since malignant transformation depends mainly on the defective function of onco and tumor superesor genes, induction of transformation has been done by viral and sh-targeting methods acting on defined genes.

    Are there other mechanisms to induce malignant transformation of cells in vitro?


  • Louis Brassard added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.


    ''We can reduce consciousness to reportable feelings and thoughts (i.e.,'access' consciousness);''

    I would rather say:

    ''We can reduce aspects of consciousness to reportable feelings and thoughts (i.e.,'access' consciousness);'

     ''We can reduce consciousness to information processing mechanisms leading to maps or representations of the body and environment.''

    I would rather say:

    ''We can reduce aspects of consciousness to information processing mechanisms leading to maps or representations of the body and environment.''

    The ''what is like'' aspect of consciousness does not seem to be reducible.  At least so far I did not see any convincing arguments.

  • Swapna Aravind added an answer in Mammalian:
    Is there a gentler permeabilization procedure for mammalian cells other than Triton-X 100?

    I am trying to stain for lipids in mammalian cells and am finding TritonX-100 to be very harsh. Please suggest gentler methods to  permabilize cells. 

    Swapna Aravind · The University of Arizona

    Thank you all for your responses. 

    I am working with formaldehyde fixed MDCK cell line. 

  • Aaron Castelan Cargile added an answer in Empathy:
    Does anyone know the most effective behavioral measure of STATE empathy?

    I am not looking for a trait empathy measure, but rather a measure (any at this point) that measures state empathy. Any help would be appreciated! 

    Aaron Castelan Cargile · California State University, Long Beach

    Here are a few behavioral (not self-report) suggestions:

    Concordant / Synchronous behaviors (e.g., EDA- http://www.ncbi.nlm.nih.gov/pubmed/23234457; Rhythmic behavior: DOI: 10.1037/a0021302)

    Heart Rate Variability / Vagal tone (DOI 10.1007/s10484-011-9161-2; DOI 10.1007/s10578-008-0104-y; http://dx.doi.org/10.1037/pspi0000010)

  • Ergin Bayrak asked a question in Uncertainty Analysis:
    How I can calculate entalpy uncertainty value which is necessary for laboratory refrigerant side capacity?

    I have completed uncertainty analysis for my heat exchanger calorimetric lab.but I am not sure the calculation of enthalpy ( it is required for Q=mr*deltaH) due to ref.prop program. Normally my main equation is U=cv*dT+P*v and I have calculated  uncertainity according to temperature and pressure sensor and I admitted constant the value of specific heat and specific weight but these values have a uncertainty due to Refprop uncertanities. I am not sure whether to add this uncertainty. I would like to learn your opinions and advices.

  • Igor Shuryak asked a question in Mathematical Models:
    Is it justified to fit a mathematical model to different types of data simultaneously?

    For example, cells were exposed to different concentrations of a toxic chemical. Two types of data were measured: (1) the critical concentration above which no cell growth occurred, (2) for lower concentrations, the steady-state number of cells which was reached after a long growth time. A mechanistic mathematical model for cell growth in the presence of the toxic chemical can predict both types of data with the same parameters. Is it justified to fit the model to both types of data simultaneously (i.e. to minimize the weighted sum of squares where both type 1 and 2 data are included)?

  • Saeed Moradi asked a question in Translation:
    Does anyone know about a methodology to evaluate the translation of affixes?

    I'm working on an article entitled the translation of -ism suffix into persian and am searching for a methodology to conduct the study.

  • Miranda Vieson added an answer in Polyps:
    Can anybody help with this image?

    I have found it in a rat colon. May be a polyp or an adenoma?. Thanks

    Miranda Vieson · Virginia Polytechnic Institute and State University

    Just a few questions for you to see if I can help.... Is this supposed to be a cross section of the colon or did you just inflate it with formalin and lay it in the cassette? I'm struggling to see where the natural borders are and orientating myself - where is the normal colonic mucosa, etc?  What did this look like, grossly?  Were there any clinical signs in this rat?  Also... any chance this is a male rat?

  • Are there informal ways/tools to encourage the self-reflection of teachers/lecturers on the way they give feedback to their students?

    In our curriculum the student needs to critically reflect on his own learning. But are the teachers capable of giving proper feedback in order to allow the student to grow in this competence? Are the teachers themselves capable of critical self-reflection? And if not, how can this be encouraged or triggered in a non-offensive way?

    Marysol Bouwens-Verloop · Hogeschool Utrecht

    Pamela;The developmental feedback will be on a single practical performance : drilling a hole in a molar and fill it with a composite restauration of a phantom head. These are bachelorstudents in their 1st year from the dental hygienist programme. The form is mainly oral feedback and partly written.

  • How the Finite Element Analysis (FEA) play their role in reverse engineering?

    I got an assignment that need to do reverse engineering. I noticed that the application of FEA, but confuse to explain the actually FEA use to do reverse engineering process. What are going to be analyze? And how to explain the result that will get from this analyze in mechanical language, not only just in number and plenty of graph or graphic result. It useful to make people which not in this field can digest what is actual we do. 

  • Nicolas Larranaga added an answer in Fish Ecology:
    Which is the best way to temporary tag 25-30 cm-long fish?

    I need to tag 25 specimens of european chub (Squalius cephalus) for a short period of time. I am interrested in the less harmful method. The specimens have 25 to 30 cm in lenght (fork-lenght).

    Nicolas Larranaga · Hólar University College

    Visble Implant Elastomers are a good, relatively harmless option. Tags fade after a relatively long period, but there is no surgery involved, other than a needle.


  • What is the climate change induced increase (per decade) in surface water temperatures and salinity in the worlds oceans and seas?

    Climate change induced an increase in the surface water temperatures and salinity in various oceans and seas in the world. I need the amounts of their increase per decade in past several years. Please attach the article as references with your valuable reply.

    Demetris Christopoulos · National and Kapodistrian University of Athens

    Dear Kenneth, thanks for the data info.

    The numbers I have posted are from the attached raw data file "PW100010148.raw.tavg" which according to the data description corresponds to the station:

    "PW100010148 34.23 -86.17 +6 01 348 ALBERTVILLE 2 SE "

    and is the first entry of the 2nd attached file station list "world1_stnlist.tavg".

    All files come from your above mentioned link:


    and more precisely from:


    So, if they make no sense, then the data source makes no sense.

    PS Why do they name their files 'world1_...', although they are strictly US locations?

  • Ruta Jog asked a question in Construction:
    Has anyone used pGCDNsam-Foxa1-IRES-GFP construct for their studies ?

    I obtained this contruct from Addgene.