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  • Arul Vadivel added an answer in Tissue Sectioning:
    Does someone knows how to score lung fibrosis in tissue sections?

    Hi, I need references on how to do the scoring for the extension and severity of lung fibrosis. Also would be great if I know how to do the scoring by my self, can anyone help?

    Arul Vadivel · Ottawa Hospital Research Institute

    You can score them after stained with Masson's trichrome (Collagen). You may score them based on thickness of the collagen deposition or severity of the fibrosis (semi quantification like 1-4 scale).

    Good Luck.


  • What is the correct interpretation of slope and intercept in W-L relationship?

    In weight-length relationship for fish species, according to literature, a is the intercept and b is the slope, so why then some statistic programs show the opposite? In a linear regression using the least square method, PAST says that b is the intercept.

    Also, with a very low value of b (under 1.00), having a sample of almost 100 fish, what kind of conclusions can we draw?


    Julia B. Smith · Oakland University

    The mathematical symbols used by regression are based on a system where every coefficient is given the letter "b" -- it uses subscripts to indicate the relationship.   So, if you have one predictor in your model, the equation is

       y = b0 + b1(predictor) + e

    where b0 is the intercept (the baseline where the predictor is 0) and b1 is the slope (the change in y when the predictor changes by one unit), and of course e is error.  This process lets us add more predictors in a linear model, so that if you have 3 predictors, regression is going to call things:

      y = b0 + b1(predictor1) + b2(predictor2) + b3(predictor3) + e:

    In elementary algebra, the equation of a slope is y=mx + b, where m is the slope and b is the intercept.  Translating what you have from regression output into the language of your field is a good intellectual exercise.

    As for your second question, I am assuming that your question "with a very low value of b (under 1.00)" is a question about the slope, which literally is again the amount that your outcome is predicted to change for every one unit change in your predictor.  The sample size is not involved in the interpretation of the value, but the units (for both outcome and predictor) are at the center of the conversation.

  • Can any one help with providing information about application of genetic algorithms in neural network apps?

    see above. 

  • Do you think whether it is proper to connect gravity exclusively with the speed of light?

    Since the beginning of the twentieth century the speed of light is thought to be fundamental to gravitation and its transmission effectiveness. Mathematical physics seeks whether this idea is sufficient for explanation of all phenomena related to mass attraction. Is a change of position needed? What is your opinion?

    George E. Van Hoesen · Global Green Building LLC


    I think that we have to press on and try to change the minds of the people that would have us band from talking but I do not think it is RG that is the problem.  The established line in Physics is strong and has no interest in new understandings.  This is no different that 100 years ago when Albert Einstein only had a hand full of people that did not think he was nuts.  He just had Max Planck on his side and as of yet we only have a few that understand but are not in prominent roles to help.

    It is however very important to keep up the good fight and push forward.  If others do not want to take advantage of the new understanding then we need to just make billions off of what will come from the better understanding and leave them in the dust where they belong.

    After all a new understanding of atoms and gravity, will only affect every living thing on earth.

  • Paramjit Singh asked a question in Coconuts:
    We are interested in procuring anthers for pollination of double coconut in our garden.We have single female tree flowering now. Can anyone help?

    Conservation Rare Palm

  • Is there any free open source software available for bathymetric mapping using remote sensing images?

    I would like to do bathymetric mapping for the Mangalore region of India, using only satellite images (where I have no ground data).

    I am new to the coastal field, so kindly suggest some good methods and open source software.

    Sebastiao Milton Pinheiro da Silva · Universidade Federal do Rio Grande do Norte

    I have to agree with everything said by JEFF. First you have to define and find out the most suitable data for bathimetric studies on shallow, deep, .... environmentsThe software is not the biggest problem. We have ILWIS, GRASS, SPRING, QGIS, ....

  • Where can i get prolog reference material ?

    I  am trying to develop rule base machine translation system using prolog so i need prolog materials please help me 

  • Taryl L. Kirk added an answer in Field Emission:
    Can we apply field emission theory of Fowler Nordheim for carbon nanotubes as well as metals?

    Assumptions of FN theory say "flat surfaces of metals obey FN theory", but CNT do not have a flat surface.

    How can we apply it in the case of CNTs? 

    Taryl L. Kirk · The College of New Jersey

    I think you have already answered your question. The conventional FN-theory is for planar field electron emission from a polycrystalline  tungsten surface. Although it is often applied to any case dealing with field electron and field ion emission, it must be modified for various parameters. Researchers have worked over a decade modifying FN-theory for CNT. Please consult some of the contemporary literature on CNT field emission. I would suggest the work done by John Xanthakis (NTUA), Chris Edgcombe (Cambridge), and Richard Forbes (University of Surrey).

  • Niloy Kumar Das added an answer in Hypoxia:
    What is Hypoxia Inducible Factor and how does it regulate cancer growth?

    I have come across this gene/protein recently and found it as jack of all trade, but i am new to this please add up its role in cancer progression and its immunological correlation if any.

    Niloy Kumar Das · Shahjalal University of Science and Technology

    Hypoxia is one of the cancer stem cells niche element which ensure the survival of cancer stem cells. This condition also turn normal cell into stemness . Hypoxia can be one of the target to eradicate cancer stem cell. I am attaching a paper, wish it could help you 

  • Ahmed Hamd asked a question in Journal Impact Factor:
    How shall i know if the impact factor of a certain journal is true or fake?

    I would like to make sure that the impact factor of any journal is true not fake

  • Chris Basta asked a question in Manifold Learning:
    What about Manifold learning approach in intrusion detection?

    What are the best cases in which the manifold learning approach can be used in? Is it a good idea to use this approach in intrusion detection?

  • How might one define the percentage of amorphous phase and crystalline phase in a powder by XRD pattern? Also, crystallite size and lattice strain?

    We have synthesised a powder by mechanical alloying. In long times of ball milling, broad peaks and high background in XRD patterns are observable. We know about Scherrer equation which defines crystallite size and Williamson-Hall equation which can define crystallite size and lattice strain, but both of them ignore how much  of the amorphous phase exists in the powder. Please tell me whether there are any other models which can define: percentage of crystalline and amorphous phases, crystallite size and lattice strain. (It should be mentioned that by Scherrer method the crystallite size is calculated as 7nm.)

    Maryam Beyhaghi · Ferdowsi University Of Mashhad

    Dear Lawrence thank you for your message, I tried to download dippfy, but I could not find which of them is OK for my system: Win 7, 64bit , the link is : https://github.com/diffpy/diffpy-release/releases/tag/v1.0

    What I understood is that they are for Linux.

  • Anyone had issues over-expressing M-MITF?

    I've sub-cloned M-MITF in a lentiviral system for over-expression and I'm having a really hard time detecting its over-expression despite >95% of cell surviving puromycin selection (and I'm sure the puromycin I'm using is working: it kills the uninfected control very efficiently and fast). I can get some low-level over-expression within the first few passages but then it pretty much disappears, despite constant selective pressure (I always use a positive control on my blots to make sure the antibody works properly). I used the same system to clone at least another dozen genes and always had beautiful signals, so I was wondering if there's anything peculiar to M-MITF that I'm not aware of? FYI I'm using HEK293 for packaging and various melanoma cell lines for the infection.


    Christian Praetorius · University of Iceland

    Hm, thats more tricky. I have used plasmid based transient overexpressions when I needed to overexpress this in different cell lines (melanoma and non-melanoma) as well as lentivirus. This worked both without problems.  Which promoter are you using to control your insert?

  • Krishnashish Bose added an answer in Sorting:
    Is there a way to sort a list of {x,y} coordinates based on both x & y values?


    This list has been sorted based on x-values. I can sort them also based on y-values. But I cannot sort them considering both x & y values simultaneously.

    should be arranged as follows:


    u see that neigbouring points allow only one unit of change in either x,y or both

    Krishnashish Bose · Nanyang Technological University


    Calculate their distances from {19,17}.

  • Can any DoE (Design of Experiments) expert help me frame treatment matrix?

    I have blocked my potential factors (x)'s into 3 independent blocks (injection, impression and injector) each block consists of 3 independent factors.., as indicated in the attached excel file., Also I wish to test each factor at 3 levels as indicated in the attached excel file.,

    In addition to all these factors there is an dependent factor (y) (sprue expansion angle) which I has to be tested at 5 levels.,

    For each combination of 3 blocks + 1 factor (y), I will be able to record a pair of response / contrast (Performance (parametric) & Quality [non-parametric])

    I'm hypothesising that irrespective of any random combination of potential factors (x)'s, sprue expansion angle (y) is significantly influences response performance and quality.,

    Also the sprue expansion significantly dependent on potential factors

    Kindly help to design an appropriate treatment matrix for injection moulding experimentation.,

    Farah Yasmeen · Monash University (Australia)

    Sorry I am unable to understand the problem. Levels of independents variables (or factors) are OK but how can you take the levels of dependent variable (Y)? It is not mentioned how the levels of Y are formulated using the levels of independent factors xi's.

  • How can the adhesion between fiber and metal be improved?

    In fiber metal laminates (FML), adhesion between the fiber and the metal is an important problem.

    How this problem can be reduced?

    Laurent Pambaguian · European Space Agency

    If you speak about glare like materials, then you could have metal structuring using e.g. laser. If you speak about MMCs you can have chemical reaction between fibres and metal or mechanical anchoring or  even both.

  • What is the best method to calculate the need for working capital for agribusiness companies?

    This issue is important, since most methods do not consider the seasonal nature. So are unsuitable for food ventures, which are often subject to strong seasonality in sales and purchases

  • Francesca Cansani added an answer in Philosophy:
    Can ethics be measured objectively?
    Ethics, ethical committee, ethical approval and other ethical related words are extensively used on Researchgate and other places. How to define and measure ethics in objective bases?
    Francesca Cansani · University of Applied Sciences and Arts of Southern Switzerland

    Dear Brandt, thank you for your FeedBack. I believe that Philosophy is not only the so called Western one. Philosophy belongs to many Cultures and Traditions, and it is tied to their spiritual Path.

    Therefore, Essence, I believe, cannot be misunderstood: it is the Core of us, the Nucleus. It has indeed to do with Spirituality, and as I [think I've] said, this is more likely to be seen in ancient Traditions, which by the Way, are still existing Today [just they've been obscured by the Darkness (!) of so called modern Science or the so called modern scientific Method. Descartes though, had said that his scientific Method was for the worldly world. The so called less genial Men, have understood that ... there was just the matterial World, or the worldly World, and that the spiritual Reality was a Nonsense. Only had Sense what could be experienced through one's Eyes or one's, let's say, technological Means, and what could be, or can be, detected by oneSelf (Self, Core, Essence) was or is Senseless. Wrong Understanding of Descartes, indeed].

    I've answered more than one Time about the main Question related to Objectivity. I've said that the Experience of Ethics is rather Subjective [see Meditation] though, if Every1 would experience it, it could be observed [3rd Eye?] by Every1 and therefore, somehow, objectively.

    Well, this Truth is at least 2500 Years old. I am not saying Anything new. Though, appearently, not Every1 is ready to wellcome it, or to understand, let's say, grasp, it.

    The different spiritual Traditions or Philosophies, should be daily Bread for so called Philosophers or Professors or Philosophy, and moreover, of Ethics. I am not talking about alien Themes, at all. I am talking about daily Bread, when it comes to Ethics and to the Subjectivity/Objectivity of it.

    Thank you.

    Happiness, Good, Light inside and Happiness, Strength [Manifestation of Good], Light outside to Every1.

  • Shailesh Gupta added an answer in EEG:
    Which mathematical model is used for EEG simulation?

    I want to simulate EEG data for different experimental conditions, and different sampling rates (from 200 Hz up to 2 kHz). Which mathematical model is used for their simulation?
    Thank you very much in advance.

    Shailesh Gupta · Shaheed Hassan Khan Mewati Government Medical College

    I believe you guys are from engineering and non-medical fields, is that ? 

    I am intrested to know about the thetretical matematical models. Well, does it have any relation with the neurophysiology n neuroanatomy watsoever? Without that its all useless, plain graffiti ... I think we need to work together. There would be some meeting point. Any isolated, with no medical corroborates would not help the cause or service. Thx. 

    I'd need more inputs from you guys.. 

  • Is there a standard protocol for promoter analysis ?

    What is the best protocol for this approach? I will be thankful if could provide me a website or other sources . Is there an algorithm for it ?

  • Khaled Saad added an answer in Down Syndrome:
    What is the nutritional recommendation for the child with autism and /or Down syndrome in early developmental stages?

    There are different types of chronic care implemented for the child with autism and Down syndrome, but what is the nutritional component of care in early developmental stages for these individuals.

    Khaled Saad · Assiut University

    Infants and children with Down Syndrome can have feeding and drinking difficulties. A smaller oral cavity and low muscle tone in the facial muscles can be contributing factors. In addition, the tongue may appear larger due to a high arched palate, a smaller oral cavity and reduced muscle tone in the tongue. Teeth tend to appear at a later stage. Many children are mouth breathers due to smaller nasal passages, and may have difficulties coordinating sucking, swallowing and breathing whilst feeding. All of these factors can impact on how a child develops efficient oral and feeding skills.

    Mothers of infants with Down Syndrome may have no difficulty breast feeding, whereas other mothers may choose to bottle feed their child. Some infants have no difficulty with the introduction of solid foods and follow the normal weaning process successfully. Sometimes parents prefer to delay the weaning process, depending on their child’s feeding skills.

    Infants who have increased oral sensitivity often have difficulty accepting new tastes and textures - intervention by a Speech and Language Therapist at an early stage will encourage oral motor and feeding skills. Some infants with Down Syndrome may require the support of a Paediatric Dietitian for feeding difficulties, poor weight gain, weaning advice, and oral sensitivity.


    Excessive weight gain is a problem for many older children and adults with Down Syndrome. Adolescents with Down Syndrome do not have the same growth spurt as adolescents in the general population. Adolescents and adults with Down Syndrome tend to be shorter than their peers, and have a lower resting metabolic rate of 10-15% than the general population which further predisposes to weight gain.

  • What is the role of hyporheic zone in contaminant removal? (Relevance to natural decontamination of polluted river water and nano-geochemistry).

    Maintenance of riparian health is a vital problem due to rising contaminant levels in the rivers and subsequent ecological degradation. I suppose that the hyporheic zone plays a vital role in decontaminating the polluted water as it percolates into the ground whereby it get diluted by mixing up with the sub-surface water.

    This mixing environment provide gradients in pH and redox conditions whereby the reactivity and mobility of metals (contaminants) are affected. Moreover, the interstitial space among the sediment grains (mostly sand) present a plugged-flow reactor system for biological oxidation of organics present in the percolating water. The biofilm that develop over the surface of the grains might have tremendous potential in decontaminating the percolating water.

    Apart from this, the geochemical interactions occurring within this zone might be distinct. The gradients in pH and redox conditions might produce layers of metal enrichment and authigenic mineral formation. The geochemical reactions occurring within this microenvironment is distinct from the bulk solution, and nano-geochemistry may play a vital role. Would like to know any direct or relevant work carried out in this direction.

    Awajiogak Anthony Ujile · Rivers State University of Science and Technology

    The hyporheic zone is a region beneath and alongside a stream bed, where there is mixing of shallow groundwater and surface water. It serves as the area where contaminants predominate. One needs to carry out the hydrodynamics and geochemical structure of the area of contamination. It is also required that the boundaries of the zone be established in terms of measurement in concrete values. This can bring out the volume estimates of the contaminants and could give a guide on the measure(s) and/rate of decontamination of the zone with appropriate tools. Certain phenomena like mass transfer, advection, dispersion and perhaps convective equations/correlations might be of help after establishing boundary conditions. In summary it enhances to determine not only the method of decontamination, but also the rate of pollutant removal from the area.

  • Bob Jarrett added an answer in Forging:
    I need information about the method for cutting bars whose name is cropping?

    One of the methods for cutting bars previous to heating for making forging parts is the cropping method. This method have a supporting bush applied to bar to accurate the squareness of the section to be cutting?

    Bob Jarrett · State University of New York Institute of Technology at Utica/Rome

    For small diameter stock, a shear with a stop block is an efficient way to cut the forging billets to length. For larger stock sizes, a circular cut-off saw replaces the shear press to yield a very precise, square cut. If the forge billets are to be upset, the shear end may not be square enough to stay plumb during deformation, resulting in non-uniform die fill. Of course, a saw cut results in some yield loss due to the saw kerf.

  • Leon Bleiweiss added an answer in Adaptive Systems:
    What are extensive classifications/taxonomies of learning tasks (ideally for Physics)?

    Hello together, I'm working now at an adaptive system for Physics and I'm going to divide physic exercises into tree categories: with low, middle and high complexity grade. The one dimension which we apply is the task/learning objective classification of Andersson but this dimension dosen’t convey all task characteristics we need like e.g. number of used formulas, number of physic concepts or decision steps. I would be very happy if somebody suggested to me any extensive classifications/taxonomies of learning tasks (ideally for Physics) that address this problem. I Thank you in advance. Best regards.

    Leon Bleiweiss · Humboldt-Universität zu Berlin

    Just a side note that might be worth your while to consider: try to point out (can be during a lecture, an exercise or elsewhere), why a particular concept (or concept block) is important and what its context is.

    E.g. The concept (block) of Mechanics  is an important part of physics because physics (in the end) is always about motion. (That's why we need it as early as in the 1st semester - where we learn it by describing the motion of macroscopic objects). Breaking mechanics down, the next most important concepts are position, velocity and acceleration - they are embedded in calculus, that's why we need to learn calculus, esp. derivatives and integrals in that particular case. etc. etc.

    Seeing the meta-concepts, the underlying interdependent, single concepts and their context usually helps the student to recognize the connections and patterns in other fields of physics and science. This again is a key strength of physicists: to quickly recognize patterns, context and analogies in anything they look at.

  • Carl Zipser added an answer in Facial Nerve:
    How to perform and evaluate facial nerve (cortical) MEPs?

    Dear community,

    does anyone of you have experience performing cortical facial nerve stimulation with TMS? If so, where do you stimulate? Any experiences with the (central) MEP conduction time in central facial paresis? I am looking forward to your suggestions!

    Carl Zipser · University of Tuebingen

    Dear Dr Modaber,

    thank you for the comment. We ruled out this possibilty by changing the coil position and the potential we received just occured when we applied the stimulus over the assumed hot-spot (estimated by mapping APB muscle first, then going lateral); thats why we are still not clear about this potential. It also is for sure no artificial coil artifact because it changes its amplitude gradually until a stable reproducible level. I am looking forward to further comments!

  • Why are my human melanoma cells attaching to my low attachment plate?

    My research concerns skin cancer and how we can treat it using natural products.

    Benjamin Samuel Goldschmidt · University of Missouri

    Can you give more information about the setup? My guess would be that the plates are old or something, but it could be a variety of things. What is the media? Are you doing anything strange to the plates?

  • Mohammad Noori added an answer in OpenSEES:
    Can anyone help me in modeling by Takeda hysteretic rule in OpenSEES?
    Which material and what parameters must be used?
    Mohammad Noori · California Polytechnic State University, San Luis Obispo

    Hello Reza,  I have done quite a bit of work in modeling hysteresis behavior especially including pinching.  I will be happy to help if you can send me a direct email and let me know what is the goal of your research.  You can contact me at:  mnoori@outlook.com

    All the best.

  • Does anyone know of an identification protocol for cyclophosphamide working surface contamination?

    I would like to simulate procedures of chemo preparation and analyze possible contamination, mainly on the surface. 

    Jonas Abrahamsson · Sahlgrenska University Hospital

    Can this article be of any help?

    Environ Monit Assess. 2014 Nov;186(11):7807-18. doi: 10.1007/s10661-014-3969-1. Epub 2014 Aug 6.
    Antineoplastic drugs contamination of workplace surfaces in two Portuguese hospitals.
    Viegas S1, Pádua M, Veiga AC, Carolino E, Gomes M.

  • Milan Ferik Tair added an answer in Linux:
    What is the best embedded platform to dump my linux c code?

    We have writting an algo in linux c which works well.But not I want to dump it to a hardware platform for better portability, power efficiency and other factors like cost scalability etc.

    So which is the best hardware platform which we can use to dump my linux c code without much changes.

    Note-We also need an ethernet connectivity and gsm connectivity with that hardware platform since basically my program collects data and sends it to remote locations using gsm.

    Milan Ferik Tair · Singidunum University

    Check out one of many SBC platforms available on the market, such as HummingBoard, RaspberryPi, Catalyst boards, ISIS PC/104, PXA 255/270/320 boards, Freescale Linux read boards, Intel's MinnowBoard...

    There are many solutions capable of running Linux distributions, so you won't have to adapt your code too much for it to run.

    Most of the boards I've listed above have Ethernet and USB connectivity.

    Oh, and they are not expensive at all. In fact, they are cheaper than a regular PC, but smaller, single board, low consumption and very portable.