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  • Chris Kelly added an answer in Inventory:
    Does anyone know what cycle inventory is? Does anyone have the proof for it's equation?

    this is to regards to average buffer inventory which is = cycle inventory + safety stock

    Chris Kelly · Kelly Partners LLP

    A useful worksheet of inventory formulae is attached.  Experientially I have found inventory often needs to be fragmented as Demand is usually different for different types of stock. 

  • RAJESH N asked a question in Metal Oxides:
    Is it possible to take dielectric studies on powder samples?

    i have prepared metal oxide nanoparticles in powder form now i want to take dielectric studies on my samples. whether powder sample is enough or make it any pellet form for this studies also mention name of the technique

  • Which is the best method to decellularized and decalcify tooth?

    Can you please suggest me the best method to decalcify and decellularize tooth without effecting its ECM components.

  • Fawad Muhammad asked a question in EndNote X7:
    Request about EndNote X6 software?

    Dear all, Kindly help me to find out the software endnote X7 or X6 for referencing and citations. my email address is fawadmhd@qq.com

  • How to implement ITR, if the classification model uses Cross validation for accuracy estimation?

    for BCI "N" class problem, how to calculate ITR (information transfer rate), if the accuracy is estimated using "p" fold cross validation technique?

    Vikram Shenoy Handiru · Nanyang Technological University

    This should give you some idea. Especially, Section II- E.


  • Chellaram Chinnachamy asked a question in Antimalarial:
    Screening of Antimalarial peptides?

    Please suggest, how to test isolated bacterial peptides against malarial parasite???

  • Hieu ho viet asked a question in Vietnam:
    What is species?

    The insect I was catch at my home in Danang Vietnam.

  • Sumanth Vasista added an answer in ER Stress:
    STUB1/CHIP is a E3 Ligase involved in the heat-induced stress response and ER Homeostasis. Would STUB1/CHIP be considered a pro survival or apoptotic?

    STUB1/CHIP is a E3 ligase protein that ubiquitylates and tags other proteins for degradation. It is involved in major developmental processes for the downstream expression and/or stabilization of other proteins. But its function is majorly seen in heat-induced stress response, wherein ER stress is regulated by degradation of mis-folded proteins in the ER, after being tagged by STUB1/CHIP.

    In fact, in vivo data for STUB1 knock-down in mice, showed increased sensitivity to heat-induced apoptosis and accelerated aging. Putting all this data together, should CHIP/STUB1 be considered pro-survival or apoptotic?

    Sumanth Vasista · Cellworks Research

    Then how can we explain the above scenario. Infact, knockdown of STUB1 increases ER stress, which sensitizes cells to proteasomal inhibitors like Bortezomib or Lenalidomide. But with a higher levels of STUB1, ER stress is not readily induced by the same inhibitors. And,

    wouldnt this paper talk about the exact opposite in T Cells?

  • George Stoica added an answer in Heritage:
    Can a Society really be Established and Sustained on Ignorance?

    The threatened, and in sadly too many cases destruction of world heritage sites by religious fundamentalists robs not only our generation of knowledge and culture but those to come.  

    This is not a new phenomenon, iconoclasm ironically predates the latest outbreak many centuries before Islam, so this cannot be a manifestation of Islam in any form. 

    Can a society or civilisation be established and sustained on ignorance and dogma or is it doomed to fail?

    George Stoica · Mathematics and Statistics

    Lots of societies in Africa are paying a big price for their leaders' ignorance (and lack of help from western civilizations). War, famine and diseases come to mind, then political oppression and aid that never reaches the needy. All of these under a thick cover of lies from local leaders and their entourages. 

  • Madhuranga Rathnayake added an answer in NAMD:
    Can anyone help me generate psf files of a membrane ligand-bound protein complex using NAMD/VMD?

    I want to perform MD simulation of membrane ligand bound protein complex but failed to generate psf files of membrane ligand-bound protein complex using NAMD/VMD?

    I have run apo membrane protein bilayer simulation of GPCR protein family, and I couldnot find any tutorial regarding membrane ligand-bound protein complex using NAMD/VMD?

    I followed this tutorial for apo  http://www.ks.uiuc.edu/Training/Tutorials/science/membrane/mem-tutorial.pdf

    Madhuranga Rathnayake · Postgraduate Institute of Science

    Hello there, 

    this might help you



  • Sittisak Pui-Ock added an answer in Incubators:
    Is the oxygen level monitored in the incubator important?

    In our lab. we have 2 versions of cell culture incubator, one is an old fashion without oxygen controlled, the another is new designed with tri gases; nitrogen, oxygen and CO2.

    Will the new version with oxygen monitoring have a better condition for cell growth?

    The only benefit which I know is tri gases incubator can do hypoxic condition for cancer cell study.

    Any comments of this tri gases incubator?

    Sittisak Pui-Ock · Chulabhorn Research Institute

    Thank you for all comments.

    For me likely that both old and new fashion incubator have the same condition for normal cell culture except we need to have special condition for specific purpose.

  • In asymptomatic patient with severe aortic stenosis do you rely on clinical parameters or perform more advanced examinations as exercise echo or BNP?

    Indications for surgical referral are different following clinical guidelines. Someone may rely only in clinical data but others prefer adding other sources of information: evolution of Doppler velocities, response to exercise with or without echo support and natriuretic peptides levels. 

    Meena Sumathy · Monash Health

    Usefulness of atrial function for risk stratification in asymptomatic severe aortic stenosis

    Journal of Cardiology05/2015; DOI: 10.1016/j.jjcc.2015.04.010.

    Hope this article answer your question.

  • Syed Fazal added an answer in Academic Writing:
    What is the difference between abstract and extended abstract?
    I am still not sure about the difference between abstract and extended abstract in computer science? how are major differences and features for each type? what is the writing style for each type?
    Syed Fazal · University of Malaysia, Kelantan

    If that is the case, then what is the difference between extended abstract and full paper? Is the extended abstract shorter version of the full paper?

  • Deepa S. Narang added an answer in 2D Materials:
    Can anyone suggest/give information about 2D materials publications/patents/review especially TMDCs monolayers year wise?


    I would like to know the present status of 2D TMDCs atomic thin materials world wide. As well number of publications (in pie form /bar chart form) in the same field.

    Deepa S. Narang · Alliance University

    Dear Mr. Kranti Kumar,

    Thanks for your response.I have around 10 review articles on TMDCs and 2D materials.I didnt get.I appreciate, if you (send me) /have any review article in which one can get the above mentioned information. 

    Thanks and regards,


  • RAJESH N asked a question in Electron Spectroscopy:
    What is the importance for XPS (X-ray photo electron spectroscopy) studies? and where is the XPS studies available in Tamilnadu, India?

    What is the importance for XPS (X-ray photo electron spectroscopy) studies and how to interpret?

    and where is the XPS studies available in Tamilnadu, India?

  • Lizhi Du added an answer in Polynomials:
    How can I revise my paper's English expression: a polynomial time algorithm for Hamilton cycle and its detailed proof?

    This is a comment for this paper I have got. But my English is bad and I need some help:

    This paper purports to present a polynomial-time algorithm for the Hamilton Cycle problem. As the author notes, this would prove P = NP. A paper making such a claim has an extraordinary burden to present its proof clearly and in a manner that can be readily checked by experts. This is because of the reasonable presumption that the claim is incorrect.

    Lizhi Du · Wuhan University of Science and Technology

    Thanks to Professor Peter T Breuer  and Professor Anthony Castaldo!

    I need more comments and then I can do something according to these comments.

    I have used some terms and expression revision from Professor Peter T Breuer.

    to Professor Peter T Breuer's latest answer: I already thought and did.

    Some Chinese suggest to cooperate with a English speaking sciencist who is strong in algorihm, it may be a good idea.

    Thank you very much!

    Lizhi Du

  • RAJESH N asked a question in Particle Size:
    Can any one suggest determine the average grain/particle size of the nanoparticles by using LASER?

    Can any one suggest determine the average grain/particle size of the nanoparticles by using LASER

  • Ramesh Prasad Bhatt added an answer in Pollution:
    How DO affects aquatic life and human being?

    Pristine or natural water is essential for life sporting system. Changing pattern of water quality affects both human being and aquatic life. Need to understand the role of DO of polluted and non polluted water.  

    Ramesh Prasad Bhatt · Institute of Ecology and Environment

    Thank you for your valuable input. 

  • George Stoica added an answer in Function Spaces:
    Do generalized function spaces still supply us with important and essential tools in analysis generally?

    The functional spaces knew a very beautiful development these last years. We see now more generalized spaces which cover several classic spaces. Is it these generalized spaces still supply us with important and essential tools in analysis generally?

    George Stoica · Mathematics and Statistics

    Do not stop at distributions, take for instance "function spaces of generalised smoothness" -  a good thesis on this subject is:


  • Is there any aspect in leadership concept, theory or the role in management or change management that needs more research?

    I want to conduct a research on leadership' concept, theory. 

    Olivier Serrat · Asian Development Bank

    Notions and practices of leadership are being upended by the rise of networks and new models of leadership in connected environments deserve investigation. In networked organizations, leadership is more often than not (and increasingly) bottom–up, collective, distributed, emergent, facilitative, and relational; the directive, top–down, and transactional leadership historically associated with, say, entrepreneurial. machine, professional, or political configurations—to cite a few of Henry Mintzberg's seven forms, is not suitable. In networked organizations the emphasis is on role and behavior, not position and formal authority. On Networked Organizations, available at http://digitalcommons.ilr.cornell.edu/intl/268/, expands on all this.

  • Paul D Jones added an answer in Gills:
    How can i quantification of liver tissue disorders in fish ?

    for example in gill tissue,  considering number of lamella(each treatment 500 lamella).

    Paul D Jones · University of Saskatchewan

    in fish liver look for hyperplasia (increased cell numbers)or for foci of hyperplasia also increased numbers of inclusions such as lipid deposits in cells. In worst cases look for necrotic areas in the liver,

  • Neba Nn added an answer in Teaching and Learning:
    Does anyone know of an instrument to assess student satisfaction of teaching?

    I am doing research on finding the effect of teaching and learning. I want to measure students satisfaction of the course. Does anyone know of an instrument to measure this?

    Neba Nn · University of North Dakota

    I did a study that analyzed the relationship between the quality of academic services and student satisfaction. I used the SERVQUAL (specifically SERVPERF) to measure student perceptions of the quality of academic services (quality of instruction).  This model assesses service quality using service quality dimensions including Tangibility, Responsiveness, Assurance, Empathy, and Reliability. This model has 22 questions that could be adapted to measure student perceptions of instructional quality. You may take a look at this link to see more information about the dimensions and questions used in the SERVQUAL Model:https://www.researchgate.net/home.Home.html

  • Kwei Kwang Chang added an answer in Cosmology:
    What is Antigravity?

    Cosmology and High Energy Expertes

    If you mean two mass expel each other instead of attract each other. That thing does not exist. Even particle antiparticle attract each other and collide into EM radiation.

    If masses  expel each other, the universe could never  be in order since stars and planets can never be formed. Electrical charges can expel, but they soon find a opposite charge and neutralize each other.

  • What is the suitable culture condition for culturing cryopreserved PBMCs for 2-3days to obtain maximal viability rate using flow cytometry?

    I have been trying to culture cryopreserved PBMCs, but PBMCs with just media alone (after 48 hours) were giving me very low viability rate when acquired on a flow cytometry. The viability rate became even lower when I stimulated them with PHA. I have used different cell numbers, L-glutamine concentrations, PHA concentrations, but none of them gave me satisfying results (with viability rate greater than 75%). I am using RPMI 1640 media with 10% FBS. 

    So, is it normal that PBMCs will just die after 48 hours, either with PHA stimulation or without stimulation? Does anyone have experience on this and can suggest me with some ways to culture my PBMCs and obtain a good viability rate?

    Jia Xiang See · University of Malaya

    Hi Paulina, sorry for late reply. Thanks for your suggestions. Yes, I realize a significant portion of my PBMCs will die after resting overnight. Is it always advisable to rest my PBMCs overnight, and only stimulate them with PHA or PMA? I will just waste a lot of my cells, and I only have limited PBMCs from each mouse to play with. 

    I certainly have to find a way to increase my viability. So far what I have noticed is that the stimulated PBMCs will always have a lower viability than that of the unstimulated one. I just hope that the viability does not go too low in both unstimulated and stimulated samples, so that I can record enough viable events and do analysis on them. 

  • Rashmi Kulkarni added an answer in Myoblasts:
    My C2C12 myotubes are coming off of the 96 wells plate, do you have any suggestions how I can control this?

    I am growing myotubes in 96 well plate for treatment with free fatty acid. However, they come off after washing or even treatment with some dye for 15-20 minutes in a buffer. This is with myotubes without treatment as well. It was not happening earlier. I observed that cell crowding at the edge of the well might be the issue, so instead of 4th day I started using 3rd day old myotubes, but still there is no change in the behavior. I am wondering how I can control this? Do you have any help?

    Rashmi Kulkarni · Indian Institute of Science Education and Research, Pune

     Hi Madhurima, 

    Actually I use a new vial for a new experiment. And as you said they adhere very well to the plastic dish. I don't see what suddenly has gone wrong. But I will try coating the plate. Also, I would like to know.. if I left the cells to form myotubes without changing differentiation medium everyday, will that form stronger myotubes ? And how many cells you seed in 96 well plate? I use cell density of 10000/ well.

    Thanks and waiting for your response !


  • Matthew Yu added an answer in Field Linguistics:
    I am looking for a text about Semiotics of colors? Can you help me?

    is the study of meaning-making, the philosophical theory of signs and symbols.[1] This includes the study of signs and sign processes (semiosis), indication, designation, likeness, analogy, metaphor, symbolism, signification, and communication. Semiotics is closely related to the field of linguistics, which, for its part, studies the structure and meaning of language more specifically. The Semiotic Tradition explores the study of signs and symbols as a significant part of communications.

    Matthew Yu · Konkuk University

    Hi, Luiz, now we see you are something an ornithologist, not a linguist? That would make a big difference because all the replies, including mine, are intuitively intended to regard color study as within the domain of linguistics, not in other fields. But what you have mentioned in your latest relpy is very interesting, it seems that the colors in the bird's feathers have their own morphology and syntax, and semantics or pragmatics maybe, Rozália has mentioned in her reply, colors have their own grammar. It is fascinating that they also evolve in time just like natural languages do!

  • Amogh Sivarapatna asked a question in Growth Medium:
    Is it okay to freeze aliquots of cell culture medium and thaw for use when needed? Will the growth factors and other components hold up to freezing?

    Trying to freeze an EC growth medium for later use

  • Is biological nitrogen fixation (BNF) in soybean kept active even in reproductive stages? In this case, would nitrogen application make sense?

    In studies aimed to evaluate the soybean response to nitrogen fertilization in reproductive stages, the rationale for nitrogen application is the assignment or decrease in BNF after flowering. However, I think that if the BNF continues during the reproductive stages, such justification would not make sense.

    I appreciate if someone can help me.

    Vítor Gabriel Ambrosini · Universidade Federal do Rio Grande do Sul

    Susantha Jayasundara and D. Kalaivanan, thank you for your answers! They were very helpful.

    This review by Salvagiotti is really good but not answers all my doubts. Actually, my doubts are relative to the maintenance or not of BNF during reproductive stages. And, because of that, how it should be managed the nitrogen fertilization.

    My doubts arose when I read an article of IPNI Brasil, written in portuguese by Dr. Gil Miguel de Sousa Câmara. The author showing in graphics two peaks of BNF, one on flowering and another on pod filling (Figures 1 and 2 of article) and affirm that most of the FBN occurs in reproductive stages. So, to apply nitrogen even in reproductive stages would not be recommended because inhibits the BNF.


    Vítor Gabriel Ambrosini.

  • Michael Brückner asked a question in Universe:
    What are philosophical questions we will never solve?

    I've recently stumbled on George Dvorsky's post on io9 (http://io9.com/5945801/8-philosophical-questions-that-well-never-solve). He brings forward 8 such questions:

    1. Why is there something rather than nothing?

    2. Is our universe real?

    3. Do we have free will?

    4. Does God exist?

    5. Is there life after death?

    6. Can you really experience anything objectively?

    7. What is the best moral system?

    8. What are numbers?

    For natural scientists Question 2, 6 and 8 seem to be particularly disturbing if they cannot be answered. In this case, we have to rely on assumptions here.

    My query to you is: Are there any other such fundamental questions that we have to leave unanswered?