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  • Alain Manuel Chaple Gil added an answer in Dentition:
    Is there any tooth numbering system which designates specific code/symbol to supernumerary/ supplemental teeth?

    standard tooth numbering systems denote only normal dentition (central incisors to molars) but when you need to incorporate presence of supernumerary teeth in case records there is no standardized system.

    Alain Manuel Chaple Gil

    Very interesting Claudia.

    Best regards.

  • Vincenzo Pasquale Giofré added an answer in Railway Engineering:
    Does interdependencies exists between railway infrastructures sets (traction power,signalling,telecoms and track) for performing reliability analysis?

    The electrified railway infrastructure set comprises of telecommunications, signalling, traction supply and the track. I intend to perform a reliability analysis on the railway infrastructure system which comprises infrastructure sets highlighted above as components. For me to complete this study I have to establish whether indeed an interdependence exists between all or some of the infrastructure sets (components) stated for the reliability analysis to be successful.

    Does an interdependence exists? If so between which infrastructure sets?

    A suggestion on articles that performed similar studies within the railway industry will also be of great use.

    Vincenzo Pasquale Giofré

    I agree with René Schönemann, I think it's a good way

  • Jochen Wilhelm added an answer in Biostatistical Methods:
    Which statistical test should I use on dose-response measurements?

    I am currently doing some studies in which I incubate PBMCs from 4 different donors with a concentration range of a drug for 3 different incubation times.

    In other words: PBMCs are purified, 6 different concentrations of the drug (0 / 0.01 / 0.03 / 0.1 / 0.3 / 1 ng/ml) are added and the cells are incubated with the drug for either 3, 24 or 48 hours before I measure cytokine levels.

    I would like to test whether the concentration of the drug plays a significant role in the cytokine response and at the same time I would like to know whether the amount of incubation time is a significant factor as well.

    Which statistical test should I use? I have considered using a two-way repeated measurement ANOVA but I am not sure whether this makes any sense? I guess both time and concentration would be independent variables whereas the cytokine concentration would be the dependent variable?

    I would really appreciate some help, since my statistics skills are really lousy.

    Jochen Wilhelm

    The probelm is that you have not specified your problem statistcally in an unambigious way. "I would like to test whether the concentration of the drug plays a significant role in the cytokine response" is be no means any statistical hyothesis.

    To turn this into something useful you would need a (kinetic) model, some assumed functional relationship between dose, time, and response. You will recognize that there is a large variety of possible relatiionships, like for instance a saturation curve, a logistic curve, or even an optimum curve (having some peak) - or yet something entirely different. Depending on this assumed model there will be some parameters having particular meanings. This can be the satuartion (maximum) value, the dose or time for 50% saturation ("EC50"), the initial slope of the curve, the slope at the EC50, but it can also be the dose/time at the peak response,  the witdth of the peak, or some measure of the symmetry of the peak etc. So you would need to specify what property of your model you are actually inetested in. Then you can statistically test your model against a model with a resticted vaue for the particular parameter. But even better you would automatically get estimates for the parameters, telling you quantitatively the kinetic properties of your system.

  • Naseem Jamnia added an answer in Globus Pallidus:
    Can you help me identify this mouse subcortical brain region?

    I am interested in identifying the brain region displaying relatively high immuno-reactivity for a protein of interest (red) in the attached images of a mouse brain (co-labeled for NeuN-green). I can identify that the signal is adjacent to the caudate, mostly posterior-medial to it. But as there many small structures in this region I am unfamiliar with, I'm not 100% confident picking one out from a mouse brain atlas schematic. My best guess based on the atlas is the globus pallidus - but if anyone can help confirm or refute, that would be great. I have not looked at many other potential regional markers, but the red-IR also colocalizes with GAD67 in this region.

    Naseem Jamnia

    I agree with Juan. I'm also more familiar with the rat brain but based on the shape and size of the hippocampus and the shape of the area overall I'd say you're at the BLA. Not sure if my input helps but just wanted to back Juan up.

  • Leon Hoffman added an answer in Food Webs:
    Can you suggest a statistical method to prove food web relationships?

    I have a sizeable data base with mollusca and other specific fauna remains encountered in cold water coral communities. I have no direct evidence for relationships of carnivore to its food source (e.g. a photograph of a mollusk having dinner or mollusk stomach content analyses) but I have some circumstantial data that may prove it. An example:

    I have 100 location samples analysed in detail on occurence of mollusks with a high confidence and of other fauna with less confidence. Molluscan carnivore A has been found in 10 stations, the likely food source sponge B has been identified in 15 stations. In 9 stations A and B are found together. The probability that A has been identified in a station is high say p(A)=90%. The probability that B has been observed is lower say p(B)=30%. Is there a statistical measure to prove or disprove a relationship? 

    Thanks for your thoughts, Leon Hoffman

    Leon Hoffman

    Dear Alessandro, thank you for your pointer. This would work well if my observations were perfect.

    I struggle with the uncertainty of the observations. The food source is often not reported. On the mollusca I am more certain but also not 100%. Would there be a way to incorporate these uncertainties. I think I have a different way of estimating these. 

    Regards, Leon

  • Sam Keenan added an answer in Mother-Child Relations:
    Do dying soldiers ever ask for their fathers?

    It is said that whenever a soldier is in a bad way, he asks for his mother.   Are there any known cases where dying servicemen ask for their fathers?

    Sam Keenan

    Not an example of asking for a father, but in Barry Heard's case he had a vision of his home town in Victoria. i think it is mentioned in his book "Well done those men". see https://www.penguin.com.au/products/9781921215360/well-done-those-men-memoirs-vietnam-veteran.

  • Ayad Palani added an answer in Antioxidant Assays:
    Can any one guide me about detailed protocol pdf book or articles of enzymatic and non-enzymatic antioxidant?

    actually i am work on stress enzymes(Enzymatic and Non-enzymatic antioxidant) of plants but didn't get any book (pdf )or paper from which i get step by step procedure of extraction + analysis.

    In different research paper only main points are written and i required step by step procedure with amount of chemical which used for extraction and analysis.

    Ayad Palani

    Dear Samrina Ahmed please visit www.en.bookfi.org

  • Hadi Alimohammadi added an answer in Control System Design:
    How can I find K1 K2 K3 with minimizing j function of lqr for a grade 3 control system?

    How can I minimize J for finding K1 , K2 , K3 with de algorithm.according to photo 

    Guidance: Due to the variable j in terms of k1, k2, k3 is optional comment plant should face denominators grade 3 or less than 3. Ss command values of A, B, C, D obtained initial values of X1, X2 .X3 is also optional.

    A, B, C, D  is selected optionally.

    Hadi Alimohammadi

    As our friend said: "Riccati" equation is the answer! This is a Linear Regulator Problem, you can find your answer in the book that I'll send you by massage!

  • Jamel Jebali added an answer in Mitochondria Isolation:
    Can anyone provide me with detailed protocol for mitochondria isolation from zebrafish?

    We are conducting experiments with antioxidant supplementation in zebrafish and we will like to evaluate some mitochondrial parameters (membrane potential, ROS generation, swelling assays, etc) in liver. A protocol and the liver mass necessary for mitochondria isolation should be welcomed.

    Thank you very much in advance.


    Jamel Jebali

    Dear Dr Monserrat 

    Sorry I have no experience about the mitochondria isolation! Please let me know if you need others information

    With best regards

    Jamel JEBALI

  • Md. Zillur Rahman asked a question in Fibre:
    Modal analysis of composite beam in ANSYS using SHELL181?

    I have done modal analysis of flax fibre reinforced polypropylene composite beam (Size:300x20x3 mm3, fibre orientation: 0 degree only). I gave all the properties which are needed for orthotropic materials in ANSYS. After running the following ANSYS input file, I am getting eight natural frequencies in a frequency range of 0 to 1000Hz. By doing the experiment, I have got only four natural frequencies. These four values of natural frequency are matching with the values of 4 natural frequencies out of 8 which I have got in ANSYS. Can anyone please tell why I am getting four extra natural frequencies? Or anything wrong in the input file (please see below)?

    !title Flax/PP beam(300x20x3 mm3) Vf=0.31, 0 degree fibre orienation

    !calls the preprocessor

    !Material properties

    MP, EX, 1, 1.638E10
    MP, EY, 1, 2.0601E9
    MP, EZ, 1, 2.0601E9
    MP, GXY, 1, 7.21E8
    MP, GYZ, 1, 6.63E8
    MP, GXZ, 1, 7.21E8
    MP, PRXY, 1, 0.265
    MP, PRYZ, 1, 0.553
    MP, PRXZ, 1, 0.265



    !Geometry and mesh
    RECTNG, 0,0.3,0,0.02 ! size of the specimen
    ESIZE, 0.002 !element size
    AMESH,ALL !Mesh the area


    FINISH !Exit pre-processor module


    modopt,lanb,10 !mode extraction method, Block Lanczos method, no. of mode to be extracted
    EQSLV,FRONT ! Frontal solver
    mxpand,10,0,1000 !no of expanded mode, frquency range from 0 to 1000 Hz

    DL,4,1,all,0 !constrain left hand fixed


    /POST1 ! List solutions

  • Karen Marie Allen added an answer in Community Rehabilitation:
    What is the role of a social worker in rehabilitation for females with rheumatoid arthritis?
    How are the social workers assisting in medical rehabilitation?
    Any articles/citations/literatures?
    Karen Marie Allen

    The challenge is helping women with RA with depression and pain management along with medication management/compliance. Often, the medications (steroids) contribute to weight gain and skin eruptions that can exacerbate feelings of depression.  Add living with chronic pain and impaired ADLS can further affect mood. In addition to treating depression, alternative interventions for pain management (meditation, yoga, acupuncture, group therapy, recreation therapy) can be important. Helping the team understand the emotional toll is important. Making sure there are resources for care, including insurance, and assessing for other benefits such as Social Security Disability are also important functions for the rehabilitation social worker.

  • Juan Manuel Herrera added an answer in Uterus:
    Can double-distilled water affect Immunohistochemistry results?

    I'm helping my sister with Immunohistochemistry (she has experience, I don't). She is doing it in order to determine progresterone receptors in mare uterus sections.
    In the original protocol (adjusted two weeks ago) they were told to used distilled water in some phases. This week we used double distilled water (bought for this purpose) and both times the results were negative. 
    Despite there is a doubt about the state of Xylene in the first attempt (and we changed it for the second day), my sister and her advisor doubt about the double-distilled water being adequate for the IHC, since the water is the only thing that was changed.
    Anyone can say me if there is any differences and if double-distilled water could affect the results?


    Juan Manuel Herrera

    Thanks, Meetu and Moritz!
    The pH of all the solutions (except for this Double-distilled water) were measured before being used and were ok. We didn't contemplate water pH. 
    Tomorrow we will make it again, but with distilled water (as the adjusted protocol says). Hope it works and lets us continue.
    Thanks again!

  • Marco Antonio Benavides López added an answer in Urban Planning:
    How do I divide traffic zones in a city which has a circular radial network?

    How to divide traffic zones in a city which has a circular radial network

    Marco Antonio Benavides López

    Important to understand, that when it comes to mobility must prioritize the pedestrian; then, then resolve the pedestrian mobility prioritized in the central areas, is structured vehicular traffic privileging the public transport system and lightweight vehicle in any case, avoiding areas of parking and occupation of public space.

    For a structure urban radial type, must take into account the type of activities and predominant land uses in each of the areas or urban areas to end, to be consistent with the mobility and traffic proposals. My observation would be then, before zoning areas and flows of vehicles, prioritize the pedestrian system and define the functional characteristics of each sector to integrate the mobility system.

  • Radosław Chrapkiewicz added an answer in Entanglement:
    What does it mean by entanglement of two atom with a single photon?

    How can i visualize this phenomenon?...Please interpret in detail...

    Radosław Chrapkiewicz

    Perhaps make you question more precise. You may consider an entangled state of even one photon and a single photon. For instance a superposition that a photon has been absorbed by an atom exciting it or a photon went though it and atom remained in a groud state. That's the simplest example of formally  entanglement state with a single atom. Add a second atom to make it even more entangled... 

    So please tell us: what do you exactly mean by your question and what kind of system do you consider?

  • Acinwu Ripiye asked a question in Data Aggregation:
    SPSS cannot compute Spearman's Rank because one of the variables is constant. How do I proceed?

    Hello all,

    I want to use Spearman's Rank Correlation to to measure association between two constructs - Culture and Ethics. I have coded  the Likert Scale data and aggregated the responses from the several questions in the questionnaires into two sets (Culture and Ethics) using the median values of responses from each question. However, in one of the Construct of 7 questions the median values are the same number (2). Now SPSS will not perform Spearman's Rank Correlation for the two Construct because 'one of the variable is constant'. Am I right to have used median values? What did I do wrong? How do I remedy this?

    Many thanks! 

  • Rosa Virgínia Wanderley Diniz added an answer in Sexuality:
    What are your experiences as teachers respect sexual diversity in school?

    In the diferents levels of education. 

    Rosa Virgínia Wanderley Diniz

     Prezado Rey;

    En la universidad donde trabajo actualmente el  "perfil sexual" de los alumnos está cambiando bastante pues están dejando muy claras cuales son sus preferencias. Tenemos casos de alumnos que ya asumiran publicamente, en clase de aula, en debates de disciplinas filosóficas o sociológicas. Y tenemos una política de recibir con naturalidad, orientar profesores y alumnos desta manera. Abrazos!

  • Eric Ho added an answer in Hybrid:
    Why am I seeing a band that is much higher in kd than the predicted for my protein of interest?

    I ran a western to test our GABA alpha 2 and 4 antibodies on (P1) rat brain tissue lysate. GABA alpha 2 was a success with a band at ~51kDA, but I am experiencing a problem with GABA Alpha 4 (Millipore AB5457). The predicted molecular weight for alpha 4 is 64kDa, but after a 10 minute exposure with ECL, there is only one distinct visible band at approximately 110kDa, and nowhere else. 

    The protocol for my western is:

    1. Electrophoresis @ 150V until sample clears well then increase 200V for ~5hours @ room temp

    2. Transfer was done overnight on 25V at room temp.

    3. Block 1 hour in 5% NFDM

    4. Rinse 3x with WB

    5. Hybridize with primary antibody (1:500) overnight (~20hours) @ 4C on shaker

    6. Rinse 3x with WB

    7. Hybridize with HRP-secondary antibody (SC-2004) (1:5000) 1hour @ RT on shaker

    8. Rinse 3x with WB

    9. Develop with "Western clarity ECL"

    I have attached pictures of my developed film. Since this was just to test the efficacy of our antibodies, I cut the blot in half vertically. The left side I ran Alpha 2 and the right side of the blot I ran Alpha 4.

    + 1 more attachment

    Eric Ho

    @AlbertRizvanov: Thank you for your suggestion! I am using 2-Mercaptoethanol as my reducing agent. I dilute it with 4x Laemmli Sample Buffer in a (1:10) ratio. However, our 2-Mercapoethanol is from 08/2011. 

  • Audrey Moffett added an answer in Tilapia:
    What is the best fixative for tilapia tissues?

    iam asking for the best fixative for tilapia tissues , tissues can remain in it for long time untill use

    Audrey Moffett

    I'am still learning on that! We've used 4% buffered formaldehyde solution (i.e. 10% formalin) for long-term storage (for fish ovary), and I don't exactly know why, I experienced some problem with tissue quality... You have to make sure that potential evaporation does not concentrate your solution (adjust if needed during storage). Also, make sure to entirely get rid of the fixative with the proper products (when proceeding to the next steps) especially if tissues were fixed for a while. 

    But first, what is the post-fixation intent? You should choose according to that. For example, if you do immunohistochemistry you'll need good quality products, and your choice may vary depending if you need to preserve soluble or insoluble compounds... 

    Here is a complete reference to learn in details the wide range of choices that you have (please see the linked book, by Bancroft and Gamble - Theory and Practice of Histological Techniques).

    Also according to "Fixation" section of the following article (in Methodology) you find that fixative such as buffered formalin is better for long-term storage with regards to some post-fixation intents (please see the attached article, by Blazer). 

    + 1 more attachment

  • Leon Hoffman added an answer in Marine Gastropoda:
    Does anyone know the current distribution of the nudibranch "Tritonia nilsodhneri" for the SouthAfrica and which one is its preferred host?

    I'm looking for some ecological notes on the species from the SE Atlantic

    Leon Hoffman

    Dear Armando,

    As an addition to Miquel's link perhaps you have not seen http://www.seaslugforum.net/find/tritnils

    with interesting comments on feeding.

    Best regards, Leon

  • Eugene Frank Milone added an answer in Cosmology:
    How do astrophysicists, or others, record/analyse/display different resolutions on images of stars/galaxies if they are differing light-years distant?

    If I'm correct that images of distant stars and galaxies can show multiple celestial objects at massively differing distances away and therefore some points of light are effectively representing images from differing moments in the past.

    If those different points of light are actually derived from differing moments in time, how do observers/recorders represent the difference in time between them visually or analytically?

    Eugene Frank Milone

    Keith your initial question appeared inchoate, but looking at the responses it appears that you are mainly concerned with how distances for astronomical objects are discerned and the uncertainties. There is a general concept in basic astronomy of the distance ladder. We establish distances to nearby objects (through trigonometric parallaxes), determine new "standard candles," and expand the process until we arrive at red shifts for the most distant objects, which are luminous galaxies or quasars at cosmological distances. The recording in these processes involves first astrometry (careful measurement of positional shifts on the sky), then relative brightness of stars, clusters of stars, and galaxies, or galactic nuclei (involving careful measurement of luminous flux, and making use of the inverse square diminution of light with distance) and spectroscopy (to register the Doppler shift of receding galaxies).  The development of individual "standard candles," one of which --- the Cepheid pulsating variables --- was mentioned above, involves a much longer discussion, but I get the idea that you are not so much interested in those details. As to distance resolution, yes, as noted previously, in general the greater the distance, the greater the uncertainty.  To give you a peg, for nearby objects in the Sun's vicinity, out to a few hundred parsecs, the uncertainty is of the order of a parsec.  Does this do it?

  • Nanxi Wang added an answer in Molecular Genetics:
    How do I increase diversity when making a 4 NNK library?

    Hi, I was trying to make a library with 4NNK (diversity=10^6). I did 8 electroporations (170ng purified ligation DNA with 60uL Genehog electrocompetent cells). The cells were then recovered with totally 12mL prewarmed SOC at 250rpm, 37C for 1hr. After that, a small fraction was taken out for plating to detect transformation efficiency. The rest was transfered into 500mL fresh LB medium. The diversity was around 2-6*10^6. I was wondering how to improve the diversity? Thanks a lot.

    Nanxi Wang

    Hi Carlos, thanks a lot. I want to improve the transformation efficiency to make sure that I will have enough variants. When you say "I have found that liquid culture works better than large petri dishes (~15 cm diameter) compared to 5 mL falcon tubes", do you mean you use larger volume of liquid medium to recover the cells?

  • Sriram Goverapet Srinivasan added an answer in Quantum ESPRESSO:
    Quantum Espresso: what is the order, in terms of orbitals, in which occupations are to be specified in the pw.x input file?

    For an isolated atom calculation, the occupation for various orbitals needs to be specified in the OCCUPATIONS card, in the input file (or so I believe. It wasn't converging otherwise). But what order should I follow while giving them? Is it using the l quantum number, or the Aufbau principle? Also, should I include all the orbitals used in generating the pseudopotential I'm using?

  • Omer Iqbal added an answer in Blood Plasma:
    What is the gell-like substance in thawed blood plasma samples and is there any way to prevent it?

    This quality doesn't seem particular to an individual species (I've seen it in both monkey and rat plasma samples).  After freezing aliquotted plasma to -70C, it's thawed on ice before pipetted out using a standard Gilson pipette.  In some samples, there is a gell like substance that can clog the pipette tip and result in inaccurate pipetting. I've had it happen to maybe 1 in 10 samples.  Am I just not thawing the plasma enough?  Is there something causing protein coagulation that I can prevent in the aliquot stage?

    Omer Iqbal

    These are called cryoprecipitates.

  • Hamideh Manafi asked a question in Fruit:
    How nitrogen nutrition decreased the fruits firmness?

    How nitrogen nutrition decreased the fruits firmness?

  • Kamal Sadeghi added an answer in Primer:
    How do i find out the theortical of my PCR product?

    I've got a primer set to detect cattle DNA. I know the sequences of these primers but i do not know the length of the DNA product that is made during the PCR. I know that there is a site or program to find that out. But i do not know what that program is called. Can anybody help me?

    Kamal Sadeghi

    Hi everyone

    How can I find website like UCSC to search on Bacteria ( microbiology)?????

  • Van Ninh asked a question in ImageJ:
    How can I use imageJ to measure the Blood vessel diameter and density?

    I have included a brightfield picture of vasculature stained with GSL-1.

  • Nadia Mustapha added an answer in Cancer Biology:
    How can I explain a dramatical decrease of PARP?

    from 40  to 50 µg/ml of tested concentration of sample, I have a dramatical decrease of PARP. how can I explain that?

    Nadia Mustapha

    thanks for your answer. everything is stable, but i always find such result and i just need to find an explanation for that. why a dramatic decrease when there is not a great difference between 40 and 50 µg/ml of tested sample.

  • Daniel Dehany Scott added an answer in Propidium:
    Is there a better way to study apoptosis and necrosis in cell culture of cancer cells?

    I'm currently using Hoerchst and Propidium iodide stain for apoptosis and necrosis, but counting the cells on the fluorescent microscope is somewhat tedious? Does anyone have experience with a kit that allows easier analysis of results?

    Daniel Dehany Scott

    Hi Y.B.,

    How exactly are you using the Hoechst/PI stain to identify apoptosis/necrosis?  Are you looking for pyknotic nuclei?  I'm just trying to get a better handle on your experimental set-up.

    We use a couple of options for quantifying cell death - though we mainly look at apoptosis rather than necrosis.  Double-staining of cells with Annexin V-FITC (AV) and PI and FACS-based counting allows analysis of a large number of cells quickly - gating for AV+ PI- cells allows selection specifically of early apoptotic cells, while the AV+ PI+ population will contain both late apoptotic and necrotic cells.  To do this, we use a kit purchased from Sigma-Aldrich for this (Catalog No: APOAF-20TST), but there's lots of commercially available kits. 

    Alternatively, we've also done westerns for Caspase 3 and/or PARP1, both of which are proteolytically cleaved early in apoptosis.  Other techniques certainly exist (there's Caspase activity-directed fluorescent stains, for example, or TUNEL-based assays), but these are the ones we've previously used.

    I hope that's helpful!


  • Pietro Michelucci added an answer in Logic:
    Is science a method or doctrine?
    My claim is: science is a method, it is not doctrine. However, I'm not the one to arrogate the right to define what is and what is not science. The meaning of each term is a matter of social convention, and scientific community agree with E. Kant and Karl Popper that a claim is science provided that it is supported either by a universal and rational proof or it is tested empirically. In addition, Popper requires every scientific claim must be falsifiable.
    Nevertheless I will prove my claim. To this end let us consider a theory T. There are three countries, say A, B and C, each of which accepts T by the following methods

    A) The country A accepts T because this theory has been voted up by the people.
    B) The country B accepts T because it was exposed by a clever man in the past.
    C) The country C accepts T because there is a rational proof for it.

    In the case of A the doctrine T is a political truth, but it is not a scientific fact. In the case of B the doctrine T is a matter of faith. By contrast, in the case C the theory T is science. Notice, that the same theory can be or not be science depending on the method by means of which it is accepted.
    Accordingly, it does not matter what the doctrine T could be, what matters is the acceptance method.
    Of course science also deals with non proved claims, but these are regarded as hypotheses and this is why science is universal. To illustrate this claim let us consider two gravitation laws.

    Newton's law : M/r^2

    Einstein's law:  R_mn - 1/2 R g_mn + ⋀ g_mn = k T_mn

    Does Einstein's law reject the Newton's one? Not at all. What Newton says is that the three Kepler's laws can be deduced from the gravitational law M/r^2. and this is proved to be true. The proof is a mathematical one. Even if tomorrow everybody awakes flying in the space, because the gravity vanishes, the three Kepler's laws can be deduced from M/r^2.
    Nevertheless if some people makes a dogma from the Newton's law, then this dogma is rejected by Einstein's law, but no dogma is science.
    Pietro Michelucci

    Perhaps scientific doctrine is a shared set of beliefs held by members of the scientific community concerning the validity and utility of the scientific method. This construal supports the co-existence of a scientific doctrine and a scientific method, and poses an alternative to notion that scientific doctrine is the body of knowledge generated through scientific practice, which may be better referred to as scientific knowledge.