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  • Does anyone know how to do 3D surface graph plotting?
    I have data that looks like this:

    X -- Y -- Z
    25--30 --1.817
    25-- 40 -- 1.763
    25-- 50 -- 1.716
    50-- 30 --1.748
    50-- 40 --1.659
    50 --50 --1.648
    50 --30 --1.654
    50 --40 --1.563
    50 --50 --1.561

    I want to use the first column as x axis concentration, the second column as y axis temperature and the third column a z values as concentration . I want to display a xyz 3-D surface in that manner. What is the best way to do this? I tried Excel but didn't really get anywhere. Does anyone have any suggestions for a tool to do this? Does anyone know how to do this in Excel?
    Mahesha Manjunatha Poojary · University of Camerino

    Sorry I dont know this!  Pls post it as a separate question. Other reserachers will answe you..

  • H.G. Callaway added an answer in Ideas:
    What is the relationship between basic concepts and mathematics in physical theory?

    Doing some background reading in Einstein, I came across the following quotation which inspired this question:

    Fundamental ideas play the most essential role in forming a physical theory. Books on physics are full of complicated mathematical formulae. But thought and ideas, not formulae, are the beginning of every physical theory. The ideas must later take the mathematical form of quantitative theory, to make possible the comparison with experiment. --Einstein and Infield, 1938, The Evolution of Physics, p. 277. 

    Are "thought and ideas" central and essential and the mathematics secondary and more important for experimental results? 

    H.G. Callaway · Temple University

    Philadelphia, PA

    Dear Messing, 

    I've now had a chance to come back to your long posting --which came in near the start of this thread, and I want to briefly address the following paragraph. 

    You wrote:

    That said, there are two issues here. The first is that even mathematicians rely on hunches, speculation, thoughts, ideas, and odd sources of inspiration that (if they are lucky) become neat, tidy proofs that show nothing of the inspirations or ideas behind them. Many a physical theory was formulated by accident or via a somewhat desperate play (Planck's constant, X-rays, etc.), and there can be little in the way of physical theory without some reason to investigate a phenomenon and some formal (e.g., logico-deductive) framework used not only for inquiry but analysis.

    ---end quotation

    Here I am pretty sympathetic to what you have to say, and in tendency, it seems that you are also expressing some agreement with the Einstein and Infield quotation reproduced in at the start of this thread. 

    Einstein's point, I take it, is not to discourage more precise and quantitative formulations of physical insight, but instead to focus attention upon the importance of physical insight or concepts and "fundamental ideas."  The proofs and calculations which follow in the wake of this, may, as you say, "show nothing of the inspirations or ideas behind them." Yet Einstein places this emphasis on formative or fundamental ideas in spite of that. I think we can agree that "there can be little in the way of physical theory without some reason to investigate a phenomenon and some formal (e.g., logico-deductive) framework used not only for inquiry but analysis." 

    I think that no one can dispute the importance of mathematics in physical theory. This is not to suggest that it can never become a kind of baroque overgrowth on the body of physical theory, though. Again, I have no doubts about the importance of mathematical physics. Perhaps the most important example of the importance of this came with the work of Beckenstein and Hawking on black holes --where gravitation and QM are equally important, and much useful theory has proceeded without the possibility of experimentation, beyond the crucial thought experiments, as with the question of what happens with entropy when a disorderly physical system is lowered in a container into a black hole. How is the physical development to be understood  in relation to the second law of thermodynamics? Out of this came the thermodynamics of black holes and eventually the hypothesis of Hawking radiation. 

    But even such results of mathematical physics can be understood in more conceptual terms, and I submit, it is worthwhile trying to do so. This will not make physicists of us, but it can inform the philosophy of science and public attention to developments in physics. 

    I notice that you have some further comments on the role of mathematics in quantum theory. Perhaps you would care to develop your related points. 

    H.G. Callaway

  • How do you treatment of medullary carcinoma after hemithyroidectomy?

    Medullary thyroid carcinoma

    Awad Ali Mohamed Ahmed Alawad · University of Medical Sciences and Technology

    Once a diagnosis of MTC is confirmed histologically by fine needle aspiration and a metastatic work-up is completed, patients should have primary surgical resection with lymph node dissection. Total thyroidectomy is the appropriate treatment for primary tumour, accompanied by a central node neck (levels VI and VII) dissection. The goal of this operation is to remove all thyroid tissue and all nodal tissue from the level of the hyoid bone superiorly to the innominate vessels inferiorly.

    I think you should do completion surgery for this patient.

  • Hanno Krieger added an answer in Nuclear Reactors:
    Can someone suggest the equation related to the neutron flux in fluence rate in the thermal nuclear reactor?

    I would like to know the equation related the neutron flux with the fluence rate in nuclear reactors.

    Hanno Krieger · retired from Justus-Liebig-Universität Gießen

    A small correction to terminology in particle physics and dosimetry:

    the number of particles passing through an area per unit time is called flux density.

    Flux or fluence is the numer of particles passing per unit time.

    So the area integral over flux density delivers flux.

  • Ahmad Olimat added an answer in CloudSim:
    Is there a tool(s) to evaluate Qos (quality of service) attribute in the context of cloud computing ?

    I'm working on cloudsim and i need a tool that evaluate as much as possible quality attributes

    Ahmad Olimat · Hashemite University

    Thanks Ali,
    what i want is to measure the Qos far away from the simulation tool, i want to treat the evaluation tool as third party.

  • Abhay Asthana added an answer in Fenofibrate:
    How can I dilute fenofibrate, a drug which is completely insoluble in water, for intragastric gavage in rats? in oils or...?

    i have a problem with this drug..

    Abhay Asthana · Maharishi Markandeshwar University, Mullana

    Fenofibrate being a drug without any pKa is a very complex molecule with respect to solubility and thereby challenged permeability issues. The drug tends to aggregate in polar solvents like water and is never a very suitable approach to look forward for alteration in pH and polarity of the solvent to get its in molecular dispersion state. The only answer to your problem in formulation of gavage for preclinical trials can be preparing an emulsified system preferably using low to optimum HLB figure. Also, the addition of external sonication energy to optimize the size of such emulsified carrier can embark the drug payload. The caution need to be taken with respect to the permeability variations or enhancement due to utilization of surfactant, which can be countered if a drug surfactant solution can be kept as a control. Best of luck...

  • Can you recommend methods of ecological condition assessment based on change of juvenile fish community?

    How can I use the data of iuvenile fishes to give a value of ecological condition in the European running waters? I have several year long databases in the Middle-Danube section and in several tributaries, but the EFI+ does not take the data of juvenlile fishes, only the adults.

    Raymond K. Timm · Cramer Fish Sciences

    Andras, Deanna Matzen and Hans Berge wrote a nice paper in 2008 (attached) that attempts to quantify biotic integrity based on fish communities.  it might provide a method that will help you answer your question.



  • Xiaoquan Sun added an answer in VMD:
    Analyzing gromacs trajectory in vmd?

    my production run generated 2000 frames but when i i load my md.gro and md.trr file in vmd, vmd shows only 252 frames. what might be the problem? why all the frames cannot be seen? also,  i want to report here that the md.gro file generated during my md run in gromacs shows that the protein has moved out of the water box.

    please guide me as to why vmd is showing less number of frames from the 2000 generated frames.

    Xiaoquan Sun · University of Arkansas

    If VMD is running out of memory, it just crashes (That's the condition in Mac). I think you may try to set a STRIDE as 100. If VMD can load 20 frame. That means your trajectory file is OK. You need to try other command-line tools like AMBERTOOLS to deal with it. Or you can divide the big trajectory file to several smaller fragments with AMBERTOOLS or other tools. If you can, I recommend you to convert your trajectory file to DCD. It's easy-going for VMD.

  • Jaishree Tailor added an answer in ArcGIS:
    Which is the most suitable technique for Interpolation of Rainfall data in ArcGIS ?

    For doing spatial interpolation of rainfall data (vector to raster) which is the best suited technique b/w IDW & Kriging. 

    Jaishree Tailor · Shrimad Rajchandra Institute of Management and Computer Application

    What about Regression Kriging proposed by Odeh, Hengl etc

  • Omer Iqbal asked a question in Meningioma:
    Does any one know the average period between exposure to radiation and development of radiation-induced meningiomas?

    Exposure to radiation may cause radiation-induced meningiomas.  The average period between radiation exposure and development of meningioma is not fully known.

  • Juan Otaso added an answer in Violin:
    Do you know Op. 3, 9, 10 by the Belgian violinist-composer Alexandre-Joseph Artôt (1815-1845)?

    I do not know if they are fantasies, variations, for violin and piano (or orchestra).

    Juan Otaso · Hospital Italiano

    I know that Artôt's compositions for the violin include a concerto in A minor, various fantasias and airs with variations with piano or orchestral accompaniment, and, in MS. string quartets, and a quintet for piano and strings. and amiability. but I can not helpyou about it.

  • Luigi Fraccaroli added an answer in DNA:
    Where can I find a database with the ratio between the mass of DNA and total cell (or tissue) mass of cells of various animal and plant species?

    I need to extract very large amounts of DNA and I want to reduce waste and impurities. So I'm looking for the most suitable species for the purpose.

    Luigi Fraccaroli · Kalichem Italia srl, Botticino (BS), Italy

    Thank you Jonathan!

    In fact I retrieved all desired data on Kew C-value Database and on Animal Genome Size Database. I have to thank to Adriana Alberti at Genoscope, Paris.

  • Looking for Mathematical models for Trauma induced (hypovolemic Shock, Sepsis) based on non-linear adaptive closed loop control systems?

    Hello Folks,

    I am searchign for mathematical models for Trauma induced patients with Hypovolemic shock, Spesis etc based on Non-Linear Adaptive Closed Loop Control Systems.

    I would appreciate any articles or journals or thesis written that could help me develop the model various models.

    Also how would you bench test these types of systems?


    David Steinhorn · University of California, Davis

    Dr. Jerome Abrams at the University of Minnesota was interested in this topic many years ago and the application of chaos theory to MODS.....that's another lead for you.

  • Farzaneh Keyvanfard added an answer in Brain Tumors:
    Recommended tools for HARDI DTI data analysis and tractography?


    For my project, we will acquire HARDI DTI data of brain tumor patients and healthy controls in order to construct structural connectivity matrices (based on tractography results) for graph theory analysis.

    Can anyone recommend any program, preferably script-based?

    I heard of the Diffusion Toolkit/TrackVis, MRtrix, and Camino, but I don't know which one would be best for my purpose.

    Thanks in advance!

    Kind regards,


    Farzaneh Keyvanfard · Amirkabir University of Technology

    Dear Hannelore

    Since "ExploreDTI " is written in Matlab, I think it will help you more than others if you need Matlab for more processing.


  • Om Ma asked a question in Ear:
    How can I run a gel on gDNA extracted from rat ear punch?

    I need to run a gel before sequencing it. What percent gel should I run it on, and what size ladder is addecuate?

  • Ariel Linden added an answer in Propensity Score:
    Are there any examples of the use of cluster analysis in search for controls?

    We search for controls within a social experiment.

    Our social experiment is made up of 9 areas and we are searching for similar areas. We use cluster analysis to find groups of areas and then look which group is the closest to our area. We cannot use propensity scores as logistic regression with a group containing one individual (or even 9) is not very adequate.

    Do you know whether there are examples of the use of clustering for a similar work?

    We also use synthetic control, but this technique implies that we would know the outcome of our research well before the end of the experiment.

    Ariel Linden · University of Michigan

    A couple of things come to mind. First, building on Timothy's note above, you can use a matching approach that matches directly on the covariates (as opposed to propensity scoring which would fail because there is only one treatment unit and thus the model would perfectly predict treatment). In addition to Mahalanobis distance, you can try coarsened exact matching (in Stata you can get this program by typing "ssc install cem", but it is also available in R).

    The second thing that comes to mind is indeed the synthetic controls approach. You should have baseline levels of the outcome, and that is what synthetic controls use for generating the weights. Thus, you do not need to have the outcome data beyond the baseline for generating the controls. The program will give you the weights for the controls that you've chosen.

    I am attaching a link to a paper I wrote on this issue from a slightly different angle...

  • Any recommended textbook about Digital Signal Processing?

    Any recommended textbook about Digital Signal Processing for graduate level? Some lecturers suggest Schaums Outline of Digital Signal Processing, any other easy undertanding books?

    Hossein Hardani · Iran University of Science and Technology

    Hi, I suggest this book for classical Signal processing:

    Digital Signal Processing - Computer Based Approach By Sanjit K. Mitra

  • Doris Bennett added an answer in Grief:
    Can anyone recommend research on behavioral contracts for hospital patients relating to assessments of grief afterwards?

    I notice that patients with behavioral contracts because of aggression often have assessments of grief, including the recent death of a loved one. I am curious if there is a correlation and how this might limit contracts if grief is supported earlier.

    Doris Bennett · Indiana university Health, University Hospital, Indianapolis

    My pleasure.

  • For APA style, do I need to insert the page number when I'm paraphrasing a few sentences on a particular page?

    I cannot not find an authorised view on the in-text citation which is the paraphrase of the researcher's own words. I know inserting page number is the usual format when using direct quotation.

    But if I've paraphrased a few sentences on a particular page (rather than summarise the thought of the whole book), can I also insert a page number? Some say this is inappropriate, so I'm confused.

    Jessica Van Cleave · Mars Hill College

    Including the page number in the in-text citation is only necessary for a direct quote.

  • Beth Brady asked a question in SAN:
    Does anyone know what this organism is?

    Not sure if it is hard or soft shelled, but was found off the coast of San Diego, CA. thanks

  • What do you and your clients think is important in measuring psychotherapy outcome?

    As many of you know, we (psychotherapy researchers) have often focused on symptoms measures as measures of outcome. My students and I are trying to develop a more comprehensive measure that will include items about coherence, freedom to choose to mention just a few aspects of this new measure that have not always been included in past studies. My question is what aspects of psychotherapy outcome do you think a comprehensive (but short) measure of therapeutic outcome should include besides symptoms? The most helpful answers will be phrased very clearly and not include jargon. Thanks

    Shveta Kumaria · Loyola University Chicago

    As a result of therapy do I feel more hopeful about:

    The Future, My self, my relationships, my ability to cope and manage they day to day,  long term goals, expectations I have for me and my world, the expectations the world has from me. 

  • Andrey Luchnik added an answer in Dogs:
    Should we remember in the History of Gastric Surgery the following achievements?

    Today, 124 years ago, 1st successful distal gastrectomy by Theodor Billroth

    29th Jan 1881: Christian Albert Theodor Billroth Billroth (* 26. Apr 1829 in Bergen, Island of Rügen, Germany; † 6. Feb 1894 in Abbazia, Istria) performed the 1st successful distal gastric cancer resection, known as the Billroth-I-operation (B-I operation) in the 43y female patient Therese Heller, a mother of 8 children [Billroth 1881]. It was the 3rd reported try performing a distal gastric resection but the first successful one, these days known as the Billroth-I-operation. Therese Heller died 4 months later due to metastatic spread into the liver.

    Earlier, in 1879, the french surgeon Jules Émile Péan alias "The Pean" (* 29. Nov 1830 in Châteaudun; † 30. Jan 1898 in Paris) performed the 1st known and reported distal gastric cancer resection, but the patient died at the 4th postoperative day [Pean 1879].

    And in 1880, Nov 16th, the polish surgeon Ludwik Rydygier (* 1850 in Graudenz [= today Grudziądz]; † 25. Jun 1920 in Lemberg / Ukraine) had performed the 2nd but not successful distal gastric resection on a 63-year-old man named Julius Mickotajewicz who was known to have a duodenal ulcer, the patient died 12 hours later [RYDYGIER 1882]. A 2nd try at 21st Nov 1881 in a gastric ulcer patient was successful.

    The achievements above had been possible – despite of course due to the experimental work of Billroth’s pupil’s Czerny, von Mikulicz-Radecki, Woelfler and von Hacker - due to the detailed report of a medical student from Giessen, Germany, Daniel Karl Theordor Merrem [* 1790 in Duisburg, Germany; † 1859], who demonstrated the operation in three dogs, and two survived, in a dog.

    I would assume, we can learn a lot fom historic achievements not only in regard to technical surgical perspectives,

    Did you know that already these days, fast track - one of the newer hype man-made therapies in patient treatment was performed? Therese Heller received sour milk, starting "1 hour" after the operation, so maybe some surgeons start smiling as they recognize that the hype “fast track” had been already in use long time ago.

    However, Billroth performed 41 gastric resections until 1890 and only 19 had been successful, meaning less than 50%.

    Other achievements of Billroth had been:

    1870 1st successfull esophagectomy ina a dog
    1873 1st successfull laryngectomy in a human
    1874 discovery of the streptococcus

    PEAN, J. E. (1879), Gaz. Hop. (Paris), 52, 473.
    RYDYGIER, L. VON (1882), Berlin. klin. Wschr., 19, 39 and RYDYGIER, L. VON (1882), Zbl. Chir., 9, I98.
    BILLROTH T (1881), Ibid., 31, 162.
    BILLROTH T (1881): Offenes Schreiben an Herrn Dr. Wittelshofer. Wien Med Wochenschr;31:162-5.

    Andrey Luchnik · Russian Academy of Sciences

    Dear Björn!

    Yeap you are right again. But the word 'yeap' is taken from famous song by VENUS
    (Van Leeuwen)
    The Shocking Blue - 1969 (The Netherlands)
    Banarama - 1986:

    'She's got it

    Yeap, baby, she's got it
    I'm your Venus, I'm your fire
    At your desire
    Well, I'm your Venus, I'm your fire
    At your desire

    Venus was her name

    Yeap baby she's got it
    Yeap baby she's got it
    Yeap baby she's got it
    Yeap baby she's got it'

    I'd like to use genuine English. Unlike those people in a subway. However it is inevitable, the evolution of language. In Russian it is the same. Even worse. 

    I have to remind that all modern languages (English, French, Russian, German) were born at the beginning of XIX centuary thanks to great writers of their countries. I adore all those writers and poets. Perhaps it is my fault.

  • Christin Geißler added an answer in Cell Culture:
    What is a suitable substitute for Quantum 263 media?
    I am looking for Quantum 263 media, originally sold by PAA. PAA was bought by GE LifeSciences and they are not offering the PAA media line. Does anyone know a medium that has a similar composition (see attachment)?
    Christin Geißler · University Hospital Frankfurt

    Thank you for your fast answer.

    Quantum is also supplemented with Soybean Extract and that Iron Binding Molecule. In principle i do not know if it is essential for my cell culture.  So I have to check it, a lot of work.

    But it is Friday. So have a nice weekend.

  • Artis Mednis added an answer in Deployment:
    Which is good WSN kit for Research works?

    My students wants to use a WSN kit practically and deploy algorithms on this network. Can anybody suggest  which is good WSN kit for Research works?

    Artis Mednis · Elektronikas un datorzinātņu institūts

    @Dr.Chandrakant Naikodi - it seems that at least one possibility is to buy direct from Advanticsys http://www.advanticsys.com/shop/asxm1000-p-24.html

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

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

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

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

    Personally, I agree with Stanislas Dehaene's opinion.


    Why don't you try to synchronize your retinoid model with the holographic hypothesis? I have no shares and no priority rights!


  • What is the effect of heavy metals on soil EC (electrical conductivity) during Phytoremediation process?

    During phytoremediation of heavy metals in pot culture, what will be the effect on soil EC (Electrical conductivity). Its increased or decresed afetr phytoremediation

    Eucharia O Nwaichi · University of Massachusetts Amherst

    Dear Ratan, from my experience in several phytoremediation experiments, EC increases with increasing bioavalable fraction of metals and metalloids.


  • What type of research methodology suitable to study the experiences of science teachers at secondary level?Any supportive literature available?

    Science Teacher Educators, Policy researchers, Science Teacher Leaders

    Azhar Qureshi · Georgia State University

    Thank you for your suggestions. My initial thinking was very similar to it.Please let me know if you find any comparative studies/justification of mix methods as compare to qualitative methodologies in Science Education.


  • Deepraj S. Bhandarkar added an answer in Heparin:
    What is your practice regarding thromboprophylaxis in patients undergoing laparoscopic abdominal surgery?

    Do you use standard heparin or low molecular weight heparin?

    Do you use it selectively or routinely?

    In case of selective use: who is given thromboprophylaxis?

    Have you encountered DVT or Pulmonary embolism after laparoscopic cholecystectomy or TAPP? If so, what is your incidence?