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  • Sutomo Sutomo added an answer in Seed Dispersal:
    How much time does it take from seed dispersal to recruitment in post fire condition?

    I am trying to quantify the time needed for indirect canopy regeneration of burnt areas (i.e. from patches or individuals that didn't burn). Did somebody com across any estimates of primary and secondary dispersion of seeds? Also what factors could prevent this process?


    As suggested by S. Hari I specify that I am interested in particular in mediterranean low forest, composed both by pioneer (seeder) and postpioneer plants and where crown fire are the most common. My question arises from the need to give indication to forest workers on when they should look for signs of recovery


    Sutomo Sutomo · Edith Cowan University

    Based on experience working in tropical savanna in Indonesia, seed dispersal is significantly assisted by grazing animals. Usually water buffalo, deers, and bos javanicus ate pods of Acacia nilotica in dry season, when they excreted their scats in areas of their range including post fire sites in the savanna, the seeds remain viable in their droppings and usually not long after the first rain in the wet season, the seeds germinate.

  • Don Shelton added an answer in Musicology:
    Is there a 19th century musicological scholarship of Thomas Arne's "When Britain first at heaven's command"?

    I have become intrigued by the musical devices employed in such a simple piece of music as Thomas Arne's closing chorus to Alfred "When Britain first at heaven's command"; My latest fascination has been with the Bassoon line as that's my primary area of study right now.

    That particular part is so lovely but the question arose in my mind. How did this piece become the quintessential patriotic song.

    But my question for wider consideration is in the area of prior scholarship on this point. Surely there is a 19th century clergyman who studied the rhetorical devices (and there are many - try the 3 sixteenth note syncopated flutterings throughout). How do these devices so clearly define the "us" group which triumphs over the "them" group (to put it in simple terms)?

    Don Shelton · Independent Researcher

    I cannot answer your technical question about the bassoon, but insofar as Arne's music becoming more popular, I think that was consequent upon a tiredness of Italian music and the related theatrical changes e.g. as portrayed in Hogarth's The Enraged Musician. I recently added a new analysis of that print to my website at http://tobiassmollett.blogspot.co.nz/2015/01/william-hogarth-and-enraged-musician.html which discusses Arne and the London theatre, and it may be of interest?

  • Zhen Zhang added an answer in Recycling:
    Are there research journals on cryogenic method for recycling PVC?

    I am carrying out a study on alternative PVC recycling technologies, and I have not find any journal paper on cryogenic method. I will appreciate if anyone can tell me about journal articles on this subject matter

    Zhen Zhang · Louisiana State University

    I do not think cryogenic milling is a good method for PVC, since it fits well with rubber system. 

  • Rosemarie Isabel Herbert added an answer in PAML:
    Any advice for using PAML to estimate dn/ds for 4 sequences only?

    I am so incredibly confused by PAML. Over the last week I've read what feels like half the internet to get a good grasp on how to use it. I'm still stuck, despite using a combination of different codeml.ctl file layouts to try and dig into my problem.

    My problem is that I only have 4 sequences for each gene I am looking at. Two of these sequences are from the same species, and I want to look at whether their dns/ds ratios vary (either site specific or branch specific). The other two sequences are quite distantly related.

    I have asked both the null hypothesis and an alternative for the whole tree, and the omega's are significantly different, which means that there are different omegas over the tree.

    I then have tried to label the split between my species of interest as #1, and calculate a dn/ds specific to those two branches. The more I look at them, the more I think I should be using a ML method to compare the two.

    Is the case simply that my original 4 sequences are too divergent, and I can't ask anything using PAML, and will need to use a different method (such as HYPHY?)?

    Or am I overlooking something in my output that should be telling me what I'm looking to know? Or asking the wrong questions in the first place.

    I see suggestions for attaching the codeml.ctl file you are using to help with the troubleshooting, but honestly so far I have tried such a variety (with setting/estimating omega values, using different models (0, 1, 2)  and trying to vary the NSsites (0, 2, 7, 8).

    My supervisor is suggesting that I follow the methods of two other papers, but both use more sequences and are more closely related to the outgroups.


    Rosemarie Isabel Herbert · Monash University (Australia)

    Thanks everyone! My supervisor ended up changing the project, and so I am working on Drosophila genes now. There is such a lovely lot of them to choose from, it's making working with Paml a lot easier. It couldn't have been done without your help.

  • Adam Szewczyk added an answer in Sewage:
    What would be a pollution source of uranium in sewage (e.g. in Sewage of bathroom)? Are there references on this subject?

    I could not find any reason or references about this subject. Thank you

    Adam Szewczyk · McMaster University

    Did you measure radioactivity of the uranium you found?

  • Raul Costa-Pereira added an answer in Mammals:
    DDo you know of any body mass database?


    I'm looking for a data base of mammals body mass. Any suggestions?

    Thanks in advance.

    Raul Costa-Pereira · São Paulo State University

    A option is AnAge, a database of ageing and life history:


  • prof V.S Muralidharan added an answer in Authorship:
    How to measure authorship?
    How select order of authors in case where one person designs experiment (aim, goals, materials and methods), order chemicals/kits, select statistical tests to perform and prepare manuscript while the other run assays and statistical analysis. Is there a quantitative method/model to show what is the value of selecting kit versus running experiment with this kit?
    prof V.S Muralidharan · Central Electrochemical Research Institute

    to be frank one need not include the supervisor as he is paid for that

    it is upto the student to include the supervisor's name

    The%s i follow--- need not be followed by others

    but the corresponding author should be the supervisor if his name is added

  • Hemanta Palo asked a question in Emotion in Speech:
    How to get matlab code for percentage accuracy to classify emotional speech using rbfn, mlp,nn?

    emotional speech classification

  • How can I determine the correlation between several factors and items?

    When I do my data analysis, I use the Pearson correlation, however I have had some difficulty to determine which factor is related to which factor? Can someone help?

    Thank you. 

    Paul Louangrath · Bangkok University

    CORRELATION COEFFICIENT FOR MULTIPLE REGRESSION: Assuming that the data for Y and X are both quantitative, the model is given as:

    (1)   Y = B0 + B1X1 + B2X2 + e

    The Pearson correlation coefficient (r = small r will be relevant below) is given as:

    (2)   r = Bi(Sx / Sy)

    ... where Bi is the slope; Si = sample standard deviation. The range of of value is -1 < r < +1. Now the correlation coefficient for multiple regression in (1) is given as R (big R):

    (3)   R = sqrt[((A + B) - C) / D]

    (3.1)   A = (ry,x1)2

    (3.2)   B = (ry,x2)2

    (3.3)   C = 2(ry,x1)(ry,x2)(rx1x2)

    (3.4)   D = 1 - (rx1x2)2

    Again, the range of R is -1 < R < +1. The correlation coefficient tells the level of relationship between variables, this is not a complete analysis. With known correlation coefficient, you need to verify whether it is statistically significant. Set you confidence interval, i.e. 0.95, 0.99, etc. and proceed to the relevant test statistic then conclude. 

    REFERENCES: Attached are some articles on multiple regression. I trust this has been helpful. Cheers.

  • Mike Male added an answer in Grassland:
    Can anybody help locate published articles about rusts or smuts on the grass genera Diplachne and Leptochloa?

    Seeking publications to cite in a taxonomic revision.

    Mike Male · Charles Sturt University

    http://www.padil.gov.au/aus-smuts/pest/main/140235 Roger Shivas could probably direct you to the papers.

  • Does anyone have any idea about the left border sequence and right border sequence of T-DNA tag mutant in Arabidopsis thaliana, please?
    I have t-DNA tag (Feldmann T-DNA) mutant in seed in WS ecotype and I need to do PCR. I'm looking for left border seq. of pBR 322.
    Can I use any T-DNA borders to confirm localization of T-DNA tag (Feldmann T-DNA) mutant?

    Could any one help me with that please?
    Erin J Gilchrist · University of British Columbia - Vancouver

    This is the sequence I used for a Feldman T-DNA line I needed to genotype: GATGCACTCGAAATCAGCCAATTTTAGAC.  I can't remember where I found the original Feldman T-DNA vector sequence, but this LB primer worked well for me.

    Hope that helps,


  • Does anybody know about the energy level splitting of rare earth elements?

    I attached one figure which I would like to know the information of energy levels splitting.

    Miremad Aghili · University of Mississippi

    The big letter is the angular momentum and the number top left is 2s+1, the numbers bottom right is the total angular momentum. they split due to the angular spin interactions and relativistic corrections. external fields can separate them too. but they are there.

  • Varun Sharma added an answer in Band Gap:
    Is it a correct way to compare the band gap of the materials both on thin film and in the powder form?

    I want to find the band gap of the materials both the powder and thin film form


    Nickel oxide Nanoparticle of 20nm and 20nm thin film will show the same absorbance in the UV-Visible region? 

    Varun Sharma · Technische Universität Dresden

    theoretically no, because the phase of powdered form and film form is not same. as UV-VIS absorbance depends on e-e interactions, and e-e interactions are different for different phases

  • If cancer cells are similar to embryonic cells, how can they be converted into adult cells in the lab as a method of treatment?

    What is a transaction that will transform the path of these cells.

    Sofiane Hamidi · French Institute of Health and Medical Research


    Small cell lung cancer cell line (NCI-H446) can be induced to differentiation into neurons, adipocytes, and osteocytes in vitro.

    Differentiation strategies are studied as alternative for cancer treatment.

    here is a paper

    Cell Death Dis. 2013 May 16;4:e633. doi: 10.1038/cddis.2013.152.
    Stemness and inducing differentiation of small cell lung cancer NCI-H446 cells.

    hope it helped


  • What is the influence of the pH on imine formation in a water solution?

    At which pH imine formation reaction between water soluble aldehydes and primary amines is the highest? Can protonated amines take part in the reaction?

    Phillip Leigh Van der Peet · University of Melbourne

    Well put Tomasz, I never claim to be certain of anything but my name! Cordes and Jencks put it nicely in JACS way back when:

    "N-p-chlorobenzylideneaniline formation, like that of oximes and semicarbazones,
    undergoes a transition in rate-determining step from rate-determining dehydration of the carbinolamine addition product at neutral pH to rate-determining amine attack under acidic conditions"

    In between you will have a trough. The exact pH ranges in which these two mechanisms function at a maximum rate will rely on the substrates.

  • How do we handle the security restrictions in the use of Unmanned Aerial Vehicle (UAV)?

    Currently Unmanned Aerial Vehicles (UAV) are heavily researched in computer vision and photogrammetry for several interesting and exciting applications, but security restrictions may hamper their practical use in the near future. Is there any line of technological thinking that may help to mitigate and address the security restrictions without compromising the safety of the public?

    Margarita Mulero-Pázmány · Spanish National Research Council

    I suggest you take a look at http://uvs-international.org/ and contact them, as they have been working for years into UAVs safe integration and may help you on that. cheers

  • Julia B. Smith added an answer in Questionnaire:
    Can the questionnaire contained negative construct?

    i saw two explanation as shown in the following:

    Negatively worded items are included in questionnaires to disrupt a response set where subjects respond favourably or unfavourably to all items (Marsh, Barnes, Cairnes & Tidman, 1984).

    On the other hand, some claimed that the negative construct is excluded from the study. The reason is the expected uncorrelated relationship among negative construct with the other four dimensions has violated the assumption of a reflective measurement model as applied in this study.

    Can the questionnaire contained negative construct?

    Julia B. Smith · Oakland University

    However, you will find that the "reversed" questions do not load with the other questions even when you reverse code them (check it with factor analysis).  Disagreeing with feeling happy is not the same thing as agreeing with feeling depressed.  If you have reversed questions and use a simple agreement scale, factor analysis will separate them into two distinct constructs every time.

  • Can anyone suggest medical image database links?

    medical image databasse

    Jesús Silva-Rodriguez · University of Santiago de Compostela




    Hope it helps,

  • The Lost Works of Tobias Smollett and a War of the Satirists. Is anyone interested in 18C Eng Lit and Pope, Fielding, Hogarth, Cibber, and Smollett?

    I have started a project on Tobias Smollett, 1737-55. Detailed research shows he arrived in London in 1737 and interacted with Fielding, Pope, Cibber, and Hogarth. The research has major implications for the history of English Literature and is being slowly posted online at www.tobiassmollett.blogspot.co.nz

    The research arises from continuing investigation of themes discussed in an essay in a forthcoming book,   “A Satire, not a Sermon: Four Stages of Cruelty and Murder” in 250 Years On New Light On William Hogarth edited by Bernd Krysmanski, 45 Essays to Commemorate the 250th Anniversary of Hogarth’s Death ISBN 978-3-00-046975-6

    Don Shelton · Independent Researcher

    I do not want to add the essay to Researchgate before publication, but if you would like an advance copy of my analysis, including Paul Before Felix Burlesqued, can you please indicate via email the best way to send it to you? (I am afraid Hogarth's satire is on the same terrible subject of man-midwifery murder.)  My email address is donshelton@actrix.co.nz

  • What is the value of the specific surface energy of fully densed 3Y-TZP?

    The specific surface energy of 3Y-TZP in J/m2.

    Abdur-Rasheed Alao · James Cook University

    Thank you Yang. I am really impressed with your analysis. 

  • Hemanta Palo added an answer in Emotion in Speech:
    Where can I get emotional speech database in English or Bangla?

    I am working on emotion detection from speech.

    Hemanta Palo · Siksha O Anusandhan University

    why not try savee data base

  • Maciej J. Chrunik added an answer in Viscosity:
    Viscosity of mixed liquids

    If two (or even more) non reactive but mutually soluble liquids are mixed, is the viscosity of resulting compound an additive value? If yes, is the contribution of each component fractional with respect to final viscosity?

    Maciej J. Chrunik · Military University of Technology

    Dziękuję serdecznie za pomoc !

  • Aedan Roberts added an answer in DNA Extraction:
    Can anyone help me with a protocol for extracting DNA from cells leftover at the bottom of a Ficoll or Lymphoprep gradient
    We'd like to extract genomic DNA from the cells leftover at the bottom of the tube after a Lymphoprep PBMC isolation, rather than waste any whole blood to extract DNA (as we want to maximise the PBMC yield). Does anyone have experience with this? Do the cells need a lot of wash steps to remove residual Lymphoprep?
    Aedan Roberts · Children's Hospital at Westmead

    It's presumably too late now, but in case anyone else stumbles across this while looking for something else as I did, this paper might be useful: http://www.biomedcentral.com/1756-0500/6/440

  • Akira Kanda added an answer in Quantum Entanglement:
    Can quantum entanglement be explained in terms of Einstein-Rosen bridge?

    What do you think on quantum entanglement? 

    Akira Kanda · University of Toronto


    Unified Theory does  what is impossible. Indeed impressive. Think about the Lorenz Force and the second law. Only an idiot or mentally ill will say we can unify them. Please keep dreaming.

    The problem with these people is that they try to unify theories which they have no understanding at all.

    The reason why this keeps happening is simply because is is a simple minded community of simple minded upstarts who take themselves too seriously. Please have a big success in your grand community.

    It was Dr. Phippe, yes one of the cranks, who said you guys are building a Spanish castle on a dung heap. Well said.

    Let me give you an advice. When you make a strong claim, you must present supporting argument.

  • Does anyone know anything about large-scale ecological monitoring infrastructures?

    I am interested on knowing about the existence of instrastructures located in large (more or less large) nature areas collecting environmental data. Stations equipped with sensors (water, pollution, soil.), or cameras installed in the field.

    Thanks in advance.

    Margarita Mulero-Pázmány · Spanish National Research Council

    thanks to all for the answers!

  • Where can I find the questionnaire "The clinical learning environment inventory (CLEI)" developed by Dr. Dominic Chan?

    The clinical learning environment inventory (CLEI) developed by Dr. Dominic Chan has 42 questions. Where can I find this tool (questionnaire)?

    Lisa Winegardner · Norwich University

    Thank you, Jeanetta. I did get the questionnaire. Appreciate your input! - Lisa

  • Choi Hyungjoo added an answer in Kalman Filtering:
    What are the state of art of the estimation methods?

    I know that the title of question covers a wide area. Currently I am trying to apply Kalman Filter to estimate some parameters of a highly nonlinear system. I took a look at the papers and articles, but I could not see any obvious advances.

    If anyone can recommend me a book or a recent review article which includes and explains the state of art estimation methods, I will be glad.

    Thanks in advance.

    Choi Hyungjoo · SK E&S

    I strongly recommend using PSO(Particel swarm optimization) for parameters  estimation. It was originallly designed and introduced by Eberhart and Kennedy in 1995.

    The PSO is a population search algorithm based on the simulation of the social behavior of birds, bees or a school of fishes. Each individual within the swarm is represented by a vector in multidimensional search space. This vector has also one assigned vector which determines the next movement of the particle and is called the velocity vector. The PSO algorithm also determines how to update the velocity of a particle. Each particle updates its velocity based on current velocity and the best position it has explored so far; And also based on the global best position explored by swarm. All of the particles have the fitness values which are evaluated by the objective function to be optimized, and have velocities which direct the flying of the particles. The objective function is to minimize the integral squared error involved in the analysis system.

    The optimization method can be identified as an effective way to find unknown parameters of a gray system. Also, more complex multi-parameter can be derived under the measred reference data. The PSO algorithm can be easily implemented and find resources on the website.

  • Prasanna Waichal added an answer in FPGA:
    Can we process a 5.8GHz RADAR signal with the bandwidth of 160MHz using NI Compact RIO? Are there any other ways to do so using hardware?

    I am working on a project which includes RADAR processing using FPGA

    Prasanna Waichal · Fiji National University

    Well Ashish,

    The Compact RIO can be part of your system, it is not the solution. You will require additional modules to the base of this Compact RIO module.

    Keeping aside what your CompactRIO system is currently being used for, I would suggest that you downconvert your RF to a suitable IF and then use appropriate ADC for sampling the IF. There are good number of IF sampling ADCs from many vendors like Analog, TI, etc. so you can choose a particular chip/set from the ones available. FPGA will come into picture where you have your fixed signal processing tasks ported to VHDL from your preliminary studies.

    Again your bandwidth is 160MHz so you will also have to work your RF/IF front-end circuit before the ADC.

    Best Luck!

  • Jehan Alam added an answer in Cell Sorting:
    Any suggestions with sorting of transfected cells?


    I transfected cells with pcDNA3.1-X and then kept the cells in G418 to make a kill curve even at the highest concentration of G418 non-transfected cells survived, can anyone suggest me 

    1) How to get 100 % transfected permanent cell line ?

    2) Any Idea of single cell seeding in 96 well plate and screening with the easiest way?

    Thanks in advance 

    Jehan Alam · Seoul National University

    Thank you Christian Gabriel and M.Y. Bilal for good suggestion.