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  • Terence Babwah added an answer in Polypharmacy:
    What could be the possible spectrum for the usage of comorbidity polypharmacy score other than to triage geriatric trauma patients?

    Other usage of CPS.

    Terence Babwah · The University of the West Indies, Trinidad and Tobago

    Comorbiidity score can also be used in triage of elderly patients who present with delirium and whose immediate etiology is unknown.

  • Babak Sabermarouf added an answer in Leptin:
    What is the effect of glucocorticoids administration on gherlin and leptin levels?

    Steroids can affect gherlin and leptin levels

  • Deniz Kuscuoglu added an answer in ER Stress:
    How can I detect very early endoplasmic reticulum stress?

    I have a gene whose expression is already altered even after the first hour of treatment. Nevertheless, this time is not enough to detect the overexpression of endoplasmic reticulum stress markers as CHOP10 or HSPA5. Does anybody how I can detect ER stress at this very early point?

    Deniz Kuscuoglu · University Hospital RWTH Aachen

    Hi Ricardo,

    here is a paper that may have answers to your question.

    Lin J. et al., 2007. Science. IRE1 Signaling affects cell fate during the unfolded protein response. They showed that the behaviour of ER stress players varied markedly in a time dependent manner. Hope that it will give you an insight! All the best!

  • Marc Bouchoucha asked a question in PERMANOVA:
    Exclude interaction terms of a PERMANOVA?

    Hi, do you think it could be correct to exclude interaction terms in a Permanova? I have 4 factors and I'm only interrested in exploring main terms and only some meaningful interactions of 2 factors.

  • G.D. Ceniccola added an answer in Psychological Trauma:
    Can anyone suggest good material on nutritional screening for ICU patients?

    I Work with trauma patients. If anyone knows specific material for such patients you helps even more. Thanks in advanced. 

    G.D. Ceniccola · University of Brasília

    Hey Sonali Vadi,

    thanks for the help! 

  • Gabriel Arantes Tiraboschi added an answer in Flicker Fusion:
    How do I develop and use Computer-based Critical Flicker Fusion Threshold assessment software?

    I intend to develop a computer-based Critical Flicker Fusion Threshold assessment software to measure CFF. Does anyone have any suggestion on how to do it? The best way to do it would be a gray background and a small round stimuli changing from black to white?

    Gabriel Arantes Tiraboschi · University of São Paulo

    Dear Dr. Watson, thank you very much for this book chapter, I need to study more about the temporal aspects of visual perception, and this chapter shall prove invaluable for me.

  • Gil Goncalves added an answer in Nanoporous Materials:
    How can I synthesize Nichel nano-flowers by sol gel method?


    Gil Goncalves · University of Aveiro

    yes it is possible. I already submit a paper that allows the preparation of nickel nanoflowers at surface of graphene oxide via hydrothermal method, since it is accepeted I will send to you.

  • Syed Hasan asked a question in Visual Basic:
    Can anyone please help me about sql connection string for Visual Basic ?

    My SQLConnection String showing error!!! Please help. Thank You

  • Manoj P K added an answer in Development:
    Are information technologies a key catalyst to success and development of non-developed countries?
    We are more than ever trying to convince the young that professions dealing with IT technologies are not just for genius people, but for everyone. Right after they graduate, there is a prospect of finding jobs with monthly wages well over the average in Serbia. All they need is to be hardworking and ready to learn and move forward. IT technologies are a great way for the developing countries to advance, promote and use for the benefit of everyone. All that is needed for taking "IT steps" is: a few computers, a little space and a lot of "brain" space. What are your experiences of this?
    Manoj P K · Cochin University of Science and Technology

    Yes Sir. I fully agree with Max Stanley Chartrand Sir. 

  • C. Igathinathane added an answer in Particle Size Distribution:
    How do I calculate particle size distribution function?

    Through my simulation work, there are results plotted for particle size (in diameter), particle mass fraction and also particle size distribution function (PSDF) but I'm not quite familiar with PSDF so I can't relate each of them. Is PSDF showing any relationship between size and mass fraction? How? Please help, thanks.

    C. Igathinathane · North Dakota State University

    My article - Powder Technology 215–216 (2012) 137–146, has some information. Should you have questions, feel free to contact me. Wishing the best!

  • John D. J. Clare added an answer in Hiking:
    Any advice on the grid size and sampling design in a spatial capture/recapture study?

    I plan on using fecal samples to identify individuals within the study area. Within each grid cell I was planning on rather opportunistically hiking in good habitat, along animal paths, etc. As long as the effort is even across grid cells I am hoping that capture/recapture models will be effective? Concerning grid size, I know that probability of recapture is important, so is basing the cell size on the species' typical home range size appropriate? Thanks.

    Edit/Update: Additional Info - 

    I am planning on conducting this research on giant pandas on a pretty small scale (focusing on the borders of Wolong Nature Reserve, perhaps with a 3km buffer on either side). Other research (telemetry studies) has resulted in an average home range size of about 7 square km in this area, using minimum convex polygon (MCP) methods. There is also pretty high spatial overlap in this species. So far I have been considering grid cells of 2.25 square km to ensure effective coverage (the terrain is extremely difficult), which would also result in a grid 2 cells deep on each side of the reserve, keeping with the 3km buffer.

    On the other hand, perhaps this increases the chances of unneeded recaptures and the cell size could be increased to around 7 square km? This would also save greatly on time, which is a consideration. I am not sure which is more effective and what the trade-offs are when considering modelling/statistical analysis of the data later.

    John D. J. Clare · University of Maine

    Right, the overall effort should be larger than a home range, but the sub-sampling grain should be smaller.

  • Luis Loures added an answer in Cyberspace:
    How can I understand the term 'topological space'?

    I am studying the topic 'spatiality' and find several meanings of the topological space (spaces):

    • psychology: (Piaget 1956?) who understand topological space as perceptual, representational and the haptic perception of shape. (cognitive psychology)
    • geoinformatics:  structure of space (quality) - compactness, connectedness, orientability. The space is part of mathematical/geometric space.
    • GIS: GIS is based on a quantitative representation of the world involving spatial primitives and the topological relations between them (Dear et al. 2011)
    • cyberspace: contemporary cyberspace constitutes a space because it consists of a system of topological relations between virtual objects. This space is a topological space, rather than a geometric space, because the relations between virtual objects in contemporary cyberspace are not, or not primarily, defined in terms of geometric distance
    • geography:
    1. topological space: the term 'topology' has specific uses in designating areas of mathematics and of GIS, but in contemporary Human Geography it has also taken on a more general set of associations in relation to 'post-structural' philosophies of space.(Cloke et al. 2014)
    2. a topological space is an abstract space in which objects are subjected to abstract ordering principles, that define connections and trajectories between objects even though these objects have no location in geometric space (Brey 1998)
    3. topographical space: literally, topography means 'place writing'. Historically, the term has been applied to a number of specific kinds of geography, ranging from topographic mapping that shows surface shape and features to local studiesfocused on documenting the many material features of a place (a topography) (Cloke at al. 2014)
    • philosophy: Heidegger speaks about  topology of Being, where places are important part of the spatiality (Casey, Malpas)

    I extend my question on the top: Is it possible to use GIS tools for mental maps? I know that GIS uses (visualizes) geometric space.

    Thanks for answers


    Luis Loures · Instituto Politécnico de Portalegre

    I think the term topological space is somehow related with genius loci... 

  • Zaahir Salam added an answer in Dye-sensitized Solar Cells:
    How can i take UV–Vis absorption spectrum of dye after adsorption onto the TiO2 surface in Dye sensitized solar cells?

    how i have to take UV–Vis absorption spectrum of dye after adsorption onto the TiO2 surface in Dye sensitized solar cells. pleas help me in details.


    Zaahir Salam · Pondicherry University

    UV Vis adsorption study of TiO2 can also be done in a Solid Mode or Wet etching mode, In case of solid mode you can try using a TiO2 film on the FTO substrate with and without dye dipping for taking the UV- Vis adsorption directly here the reference will be a UV-Vis Adsorption spectrum for pure TiO2 Film without dye dipping. Or else you can try NaOH/ethanol dye etching method and then take the UV of that etched Solution for Comparison with a reference of NaOH or Ethanol. 

  • Aires Camões added an answer in Graphene Oxide:
    Has anyone ever used graphene oxide in cement-based materials?

    I found recent papers in the literature with extremely encouraging results especially in terms of mechanical performance.

    Aires Camões · University of Minho

    Hi Valeria,

    Unfortunatly I can't help you because I've never worked with graphen oxides...

    All the best,


  • Leslie Ann Caromile added an answer in Protein Purification:
    How can I find the location of proteins to find best method for protein purification?

    I want to choose the appropriate purification method.Does anyone know how could I find out that a special protein is membrane protein or cytoplasmic, nuclear.etc?

    Leslie Ann Caromile · UConn Health Center

    Try doing a subcellular protein fractionation (you can buy a kit for this). Basically, it enables you to perform a stepwise separation and preparation of cytoplasmic, membrane, nuclear soluble, chromatin-bound and cytoskeletal protein extracts from tissue samples. Extracts obtained are compatible with a variety of downstream applications, including Western blotting and reporter-gene and enzyme-activity assays. 

  • Gerald Doh added an answer in Mutagenesis:
    What is the cheapest option for amutagenesis kit?

    I have cloned an ORF sequence into pcDNA5. To obtain mutant constructs, I am looking for a CHEAP mutagenesis kit. Any recommendations? 

    Gerald Doh · Predoctoral Researcher

    Thanks Hideyo. I will read about this.

  • Rodrigo León Cordero added an answer in Butterflies:
    Some help researchers, on "the declining diversity of butterflies due to human activites?

    human activities that have escalated the problem

    Rodrigo León Cordero · University of Guelph

    Hi Vicent:

    Habitat loss is especially important for specialist butterflies, such as the Monarch butterfly, which experienced a 81% decline from 1999-2010 in some areas of the US (Pleasants et al. 2013; http://onlinelibrary.wiley.com/doi/10.1111/j.1752-4598.2012.00196.x/full)

    Larval development has been severely affected by herbicides, such as glyphosate and other practices associated to intensive GM agriculture, that have substantially reduced populations of its main resource: milkweed (Asclepias sp.)

    I hope it helps.

    Good luck,


  • Shyamal Lakshminarayanan added an answer in Principal Component Analysis:
    Can someone help with Anomaly Detection on UCI SECOM dataset using Principal Component Classifier?

    I am trying to implement anomaly detection using principal component classifier proposed in this paper (https://users.cs.fiu.edu/~chens/PDF/ICDM03_WS.pdf).It proposes that instead of using only the major principal components, it is better to use major as well as minor principal components. For example, the paper uses major principal components that explain 50% of the total variance and the minor components having eigenvalues less than 0.2.

    What I am unclear about is the selection of hard cutoffs such as 50% and 0.2. Is there any science behind it? Can anyone please explain? Thanks in advance.

    Shyamal Lakshminarayanan

    For multivariate normal data you can look at model to observation Mahalanobis distances and use limits based on Hotelling's T-squared distribution.

  • Zainab Albusaid asked a question in Rodents:
    Dose any one have information about organic dye?
    1. I have a project for staining rodent chromosomes and cytoplasm  of rodent  oocyte with organic or plant dyes I need procedure for this purpose and I need more information about these dyes 
  • Robert Hedin added an answer in Bicarbonates:
    How can I quantify the presence of carbonate and bicarbonate in reservoir water?

    Can anyone help me how to calculate the amount of carbonate and bicarbonate ions (mg/l) present in reservoir water (formation water) ? Is it possible to determine by alkalinity test or by TOC/TIC if so how?

    Robert Hedin · Hedin Environmental

    based on my experience with mine drainage and surface water in the US, 1759 mg/L CaCO3 alkalinity is a very high number.  Three times higher than anything I have measured in flowing water.  My first reaction is that there is a measurement error.  Or check to see if this level of alkalinity is common in surface waters in this region.

  • Alaa Kareem Niamah added an answer in Archaea:
    What are some group specific primers for Archaea domain?

    Is there any group specific primers for Archaea for meta genomics study of marine sediment samples?

    Alaa Kareem Niamah · University of Basrah

    You can search in gene bank 

  • Oleksandr Matviichuk added an answer in Nanopores:
    How do we need to modify the Darcy's law equation for gases in nanoporous media (Knudsen diffusion) in the case of gaseous counter diffusion?

    In particular, for nanoporous media with parameters variable in time, temperature and pressure (for details, please, see my publications on ridge-effect phenomenon).

    Oleksandr Matviichuk · National Academy of Sciences of Ukraine

    Господа пишите кирилицей. Облегчите жизнь:)

    П.С. будьте так любезны пришлите мне пожалуйста вышеупомянутую публикацию (on ridge-effect phenomenon) для ознакомления

  • Charles Francis added an answer in Theoretical Physics:
    Can Quantum 'Mechanical' Description of Physical Reality be considered Completed?

    Simplicity is the key to the interpretation of physics. Nothing more simple in the analysis than supposing the existence of some parameter "hidden," invisible and not measurable which is an integral part of a pair of photons and that tells at the time of their creation: "you are oriented east" or "you are oriented to the west. "This analysis requires us to introduce "hidden variables", a process which in physics is debatable, but allows in a very elegant way to explain everything in realistic terms. The pair of photons has its own objective reality that can describe them completely. Part of this reality is unknowable but never mind, the problem is only human, nature is safe.

    We have two options: 1) quantum mechanics is inherently probabilistic; 2) quantum mechanics is not inherently probabilistic, but deterministic. The first position is that of the so-called "Copenhagen interpretation", still very accredited by physicists, while the second was that of Einstein-Podolsky-Rosen (EPR) and of the "hidden variables". Subsequently, Bell showed that the hidden variables can not be there. John Bell in 1964 pointed the way for an experimental verification of the existence of hidden variables, but subsequent experiments, especially the French group of Alain Aspect, have shown the full validity of quantum mechanics.

    Then, the second theoretical position is no longer sustainable. Instead it is if we consider the fact that the "ontological materiality" turns out to be greater than the "physical". There are no additional variables that may enter into the physic calculation, but there are physical materials that physics fails to consider which have an impact on theorizing. These factors determine the overall behavior of matter which, therefore, appears inherently probabilistic. It can be said that Einstein was right: the hidden variables exist, only that they lurk outside of physics, in ontology.

    Many physicists (Einstein leading) have always refused that indetermination be an inherent feature of physical reality. Consequently, they preferred to assume that the description provided by quantum mechanics was simply incomplete. Their reasoning, in practice, consists in saying: even at the microscopic level physical reality continues to be deterministic, only that we can not know the exact values of the state variables and so we are forced to an indeterministic description. To explain this failure many proponents of determinism (starting from Einstein himself) introduced the so-called "hidden variables". At the microscopic level, there would be some factor that is not yet known which would prevent us from a deterministic description. The moment we knew, we could provide a description of these factors completely deterministic

    For many years the debate between the advocates of the hidden variables and the promoters of intrinsic indeterminism remained on a purely metaphysical level. In 1964, however, the physicist J.S. Bell derived a famous inequality (Bell's theorem) that allowed to transfer experimentally what until then had been a metaphysical discussion. Such inequality, in practice, led us to expect different experimental results depending on whether had been true the hypothesis of hidden variables (at least limited to the so-called "local theories") or not.

    Now, the Heisenberg principle would not only establish our inability to learn at the same time the values ​​of the position and momentum of a particle. These values are established, before a measurement be made, they are absolutely and inherently indeterminate.

    Einstein's objections to quantum mechanics made sense because he was perfectly aware that quantum mechanics is incompatible with determinism. However, his views obstinately deterministic and his attempts to defend them (hidden variables) have not stood the test of facts.

    The microscopic reality is inherently indeterminate. However, what is surprising is that the macroscopic reality is instead largely deterministic. To explain this apparent contradiction is a fascinating challenge in theoretical physics. An interesting attempt at a solution appears that provided by three Italian physicists G. Ghirardi, A. Rimini and. T. Weber (in Physical Review D 34, 470, 1986).

    So, in this context it became obvious that the description of the states of a physical system offered by quantum mechanics was incomplete and that such an incompleteness was responsible for the indeterministic character of the theory. In other words, it has been assumed that quantum mechanics is indeterministic only because our level of knowledge does not put us in a position to "see" some additional variable, able to "complete" the description of the physical system provided by quantum mechanics. According to this conjecture, if we were able to identify these new variables, currently "hidden", we would recuperate a level of description deeper than the quantum level and at that level determinism could be recovered. "

    In fact, the enigma of the "hidden variables" was not solved by a logical-deductive approach, as Popper might have wished, or was it only partially.

    As already said, “in 1964 the issue was a crucial turning point: J. Bell showed that for a large family of theories and hidden variables, the so-called local theories, it is impossible to reproduce with media operations on hidden variables all the predictions of quantum mechanics. "" the result of Bell had the great merit of showing on the experimental ground the theme of possible deterministic completions of quantum mechanics, and a great interest aroused for the realization of experiments sensitive to discrepancies between the predictions of quantum mechanics and that of the local theories of hidden variables . "(Enrico Beltrametti)

    In 1981, Alain Aspect was able to realize the first of a series of experiments of high quality. In practice, the experiment showed that Einstein had been wrong in suggesting the idea of hidden variables.

    As for Popper, we could say that he lost a game: the one with LQ,

    Criticism of Popper was wrong from a logical point of view, but in many ways it had some basis. Popper did not want to admit a weakness of logic explicit in theory LQ. For Popper's logic was to remain an ‘a priori’ science, having as main feature the absolute independence from any content. Therefore, he refused to consider the possibility of choosing logics different from the logic, most suitable than this to the empirical character of particular situations.

    Already in the Logic of Scientific Discovery, which was finished in 1934, then prior to the writing of Birkhoff and von Neumann, Popper anticipated: "... replacing the word" true with "the word" likely "and the word" false  with "the word" unlikely ", nothing is gained.

    However Popper earned another no less important point. The revolutionary discovery of Bell and Aspect was not from a pure inductivism, but from experiments carried out in the light of a theory already formulated ‘a priori’, then from a hypothesis to be subjected to strict scrutiny, identifying the elements and data that could refute it. At least on this ground, Popper took an important rematch.

    At the time of the article in Einstein's death, the controversy was still strong and "philosophical" issues had a great weight, so much so that an American physicist was the victim of McCarthyism and lost his job for supporting a deterministic model with hidden variables. Today we tend to minimize the importance of our imperfect knowledge on the subject; theories are used as they are reaping the fruits without worrying about a coherent understanding of the underlying laws. Most physicists do not interpret more the principle of indeterminism  in a metaphysical way. It is considered as a simple impossibility of knowing at the same time position and momentum of the particles in a system still felt completely deterministic. After all, beyond the supposed wave-particle duality, also in the macroscopic world there is a kind of uncertainty: for example, I can not measure my speed with accuracy higher than my reaction time to press the button on the timer.

    Charles Francis · Jesus College, Cambridge

    Sofia, you attribute too much to Bell. The addition of complex amplitudes has been a part of quantum theory since Schrodinger, Heisenberg, Dirac, von Neumann et al. The reason this works is explained by Stone's theorem. 

  • Pranav Deshpande asked a question in Performance Measurement:
    How to reconstruct back a signal from it's moving average (MA) model ?

    How to regenerate back a process after estimating moving average parameters? what kind of performance measure can be used to evaluate the corresponding model?

  • Ela Elyada added an answer in Retroviral Vectors:
    What would be an efficient way to infect primary fibroblasts?

    I'm trying to infect primary fibroblasts (NOT immortalized) with a retroviral vector, and it seems none of the cells are taking in the vector (all died in selection). My cells are attached to the dish while being infected. Any tips would be much appreciated!

    Thanks, Ela

    Ela Elyada · Cold Spring Harbor Laboratory

    Thanks guys,

    I did not measure my titer (I made it using Phoenix cells as host), but I use the same virus supernatant to successfully infect different primary cells (epithelial), in which I saw the GFP and they were also nicely selected for virus expressing cells. The virus I'm using is a Retrovirus, but not a Lenti. Do you think Retro is not good enough for fibroblasts in general (which are still proliferating)? BTW, the promoter for the Neo is PGK, I believe it should be expressed in fibroblasts, am I wrong?

  • C. Igathinathane added an answer in ImageJ:
    Does anybody know how (using imagej) to get Perfusion parameters (blood flow, mean transit time, permeability surface)?

    I would like to analyze prostate CT- Images. Is there any possibility to work with imagej fiji?

    C. Igathinathane · North Dakota State University

    The first simple step is to work with static images. If the blood flow can be correlated to the diameter of the blood vessel, we can measure it and indirectly correlate to flow. Similarly, permeability and so forth can be quantified by some features that are readily visible in a static image (e.g., SEM image) then we have something to start. Motion tracking are advanced topics and I have seen some examples of that too. Wishing the best!

  • Hui Zheng added an answer in VASP:
    Could the charge density distribution (CHGCAR given by VASP ) be separated by spin up and down?

    I am exploring a novel system which is magnetic, and I want to draw one specific band's charge distribution. How can I realize the charge separation of spin up and spin down. 

    There are two saying of the contents of CHGCAR,

    A: the first half part is the spin up charge, the latter half part is the spin down charge. 

    B: the first half part of CHGCAR is the charge distribution of spin up plus spin down(up + down), while the latter half part is spin up minus spin down (up - down)

    So, could someone could help me solve the puzzle?

    Hui Zheng · Jilin University

    Oh, I found the official statement that is second one is correct. 

    Link: http://cms.mpi.univie.ac.at/vasp/vasp/CHGCAR_file.html

    But I still met problem that, if we set M = up+down,  N=up-down, we can get up=(M+N)/2, down=(M-N)/2, but the outcome of the data is very strange. for 2D materials, there are some charge distributions where are even faraway to the sheet, in the vacuum slab, Is there someone met the same problem?

    Thank you very much for your concern and discussion! 

  • Raid Amin added an answer in Basic Statistical Analysis:
    How do I confirm whether my data fit the quadratic model if my R2 is 0.84 but lack of fit is significant?

    Model is significant with p value of 0.001.

    Lack of fit is significant too.

    Raid Amin · University of West Florida

    Hi Aishwarya,

    I would inspect a scatter plot of Y vs. X to see if you can identify any curvature in the plot or not. A more rigorous approach is to use a Box-Cox transformation. Tukey's Ladder of Re=-expression is a simple but powerful approach too. 

    R_square is not the only measure to study here. Get the PRESS too. It is a SS Error for prediction purposes. It will help you identify a model that is stable with future data values.

    Good luck.

  • Vignesh R asked a question in Research Papers:
    Can anyone suggest me quality research papers on clustering of time series???

    Need some good research papers and literature on clustering of time series... 

  • Shamsh Pervez asked a question in Mathematical Statistics:
    Can anyone assist me to identify emerging objectives and associated methodological approaches to address atmospheric wet precipitation?

    I am planing to conduct a comprehensive research study on atmospheric wet precipitation in rural and urban environment of India to address:

    1. Physico-chemical characterisation (inorganic and organic species) of rain water samples during a period of couple of years to assess associated spatiotemporal trend.

    2. Distribution pattern of measured species between aerosols and rain water along with associated atmospheric chemistry

    in connection to above stated plans, I am interested in new emerging objectives, especially for India type of atmospheric environment and different types of methodological approaches including sampling plan, choice of chemical species, and different mathematical/statistical methods of data interpretation to meet out the emerging objectives.

    I shall be highly grateful for your valuable suggestions.