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  • Balázs Farkas added an answer in Mammalogy:
    Is australis or gliroides the correct species name for Dromiciops?

    Does anyone know whether the correct binomen for the monito del monte is Dromiciops gliroides or Dromiciops australis? Looking at the taxonomic history of the species, it looks like australis was named a year before gliroides, and the holotype was never lost, so why do all publications seem to use the name D. gliroides? Was there some ruling from the ICZN or something that suppressed D. australis?

    The correct binomen is Dromiciops gliroides, because Philippi described the same species as Didelphys australis, a name preoccupied by Didelphis australis Goldfuss, 1809 (= “Pennants New Holland opossum, a phalangerid”, according to Hershovitz, Ph. 1999. Dromiciops gliroides Thomas, 1894, last of the Microbiotheria (Marsupialia), with a review of the family Microbiotheriidae. Fieldiana [Zool.], N.S., No. 93, page 26; the identity of the latter species remains obscure, though).

  • Salman Ahmed added an answer in Uric Acid:
    What is a simple qualitative test to confirm the presence of uric acid in a test tube?

    I need any simple and reported qualitative test to confirm uric acid in a test tube by color reaction/precipitate, etc.

    Please help me.

    Salman Ahmed · University of Karachi


  • Emiliano Medei added an answer in Guanylate Cyclase:
    Can HPLC be used to measure the concentration of cGMP in myocardial tissue?

    We want to determine the concentration of cGMP in ventricular tissue, in order to evaluate the activity of the Soluble Guanylate Cyclase enzyme.

    Emiliano Medei · Federal University of Rio de Janeiro


    Puede ser una buena idea, se que Ines Ferrari vio algo de eso en un paper de 2000 con Chiale...si mal no me acuerdo con el sobrenadante de cultivo de cardiomiocitos 

  • Kyrylo Greben added an answer in MDCK:
    What is the best way to perform impedance measurements on a monolayer of epithelial cells?

    I am trying to determine the best possible method to measure the impedance on my monolayer of MDCK (Madin Darby Canine Kidney) epithelial cells. 

    Does this require a specific metallic coating (via sputter coater or another method) on/ under (as a membrane the cells would grow on) my monolayer or would the liquid media itself simple provide the conductive element required?

    Kyrylo Greben · Forschungszentrum Jülich

    Hi Divya,

    can you give more details to your system, please? What kind of liquid media do you mean? Do you have SAMs and cells both? 

    Thank you,


  • Which is the best kit to remove BSA from media?


    I am hoping to remove BSA from my cell culture media (containing 10% FBS). The media is for mass spectrometry analysis.

    I was hoping someone could recommend a good kit? There are a plethora of kits on the web (and many are HSA specific).

    Any help would be appreciated.

    Teodor-Doru Brumeanu · Uniformed Services University of the Health Sciences

    It would be easier if you can use serum free media.

  • Lale Evsen added an answer in Chick Embryo:
    Can anyone recommend dissection plates for chick embryos?
    I'm doing a series of chick dissections and have been using agar plates for it. But the embryo sticks to the agar, making it difficult to manipulate. What other type of plates can I use?
  • Klaus Boldt added an answer in Tellurium:
    What is mean by the mesh size of tellurium powder and does the reactivity is different according to the mesh size?

    Tellurium (400 mesh) is not getting dissolved in Top( Trioctyl phosphine), where as 200 mesh size Te is dissolving..After all Te is forming coordinate bond with TOP (  Outer 5p shell of Te can accept the unpaired electrons from TOP) and thereby dissolving ( forming a colorless solution). So why it shows different reactivity according the mesh size?

    Klaus Boldt · Technische Universität Dresden

    In my experience tellurium is much more prone to oxidation than selenium, and it can cause problems when making TOPTe. Colleagues have encountered a grey residue, probably an oxide, that would not dissolve. Finer powder just has more surface area to oxidise. I would usually go for Te shot and either grind it just before dissolving, or heat and wait for the reaction to complete. If available, store the tellurium power in a glove box right after purchase and do all of the reaction with TOP there.

  • Stefan Danielsson added an answer in SimaPro:
    Can we do life cycle analysis (LCA) without the use of Simapro or any other software?

    Life cycle analysis is a tool which estimates environmental indices (Eutrophication potential, acidification, global warming potential) of any input added to ecosystem.

    Stefan Danielsson · Norwegian University of Technology and Science

    I learned to do LCA in EASETECH (developed by DTU) and GaBi. Simapro and Arda are used in NTNU, where students have learned to do LCA in Excel with matrixes and. However, e.g. import from Ecoinvent as an LCI database will be necessary .
    Good luck

  • Does anyone have information or materials on organizational reward strategies and scales used in the measurement of perception in research?
    I need information relating to organizational reward strategies in different cultures and a suggestion on the scales that can be use to measure perception in research.
    Emmanuel Gamor · University of Cape Coast

    Regarding perception, there are various scales you can use but it will depend on the focus of your study and the discipline. there are scales like SERVQUAL, SERVPEF, Self perception scale and others. Some of these links may be of help

    http://archiwum.ciop.pl/3503,  http://sds.hss.cmu.edu/risk/articles/NewScaleAssesPercepChance.pdf, 

    An examination of employee retention strategy in a private organisation in Zimbabwe by Chiboiwa et al. (2010) can be useful with the Organisational Strategies. 

    Have a nice day

  • Regina Agubamah asked a question in Dementia:
    What are the differences between dementia and schizophrenia patient?

    Could anyone share studies because I would like to carry out research on dementia patients in social model

  • Juana Acrivos added an answer in Mixed States:
    Can flux motion caused by external magnetic field with different angle result in a negative resistance in mixed state of a HTC superconductors?

    Like the title, can the flux motion cause some unbelievable response in resistivity such as negative value of resistance? Will the flux motion in the mixed state of HTC superconductor show different response in FC and ZFC process followed by 2 Pi angle scanning ( from c to ab to -c to ab to c)?

    Juana Acrivos · San Jose State University

    Please go to publication arKiv-cond-mat/0508058

    Figure 2a shows the orientation dependence of Abrikosov Vortex loss intensity versus external magnetic field H orientation as this  goes through zero at different arc(c^H).

    feel free to email for more to juana.acrivos@sjsu.edu

  • Does anyone know what the terms "redlive", "benworn" and 'dimifew" may have to do with maternal health or calcium supplementation?

    Working on a maternal health project

    Helena de Carvalho Gomes · European Centre for Disease Prevention and Control

    "redlive" = deliver; "benworn" = newborn; "dimifew" = midwife

    Is this a serious question?

  • Can someone provide advice on BER calculations using VPItransmissionmaker?

    In my setup, the probability density function of the noise is not Gaussian-like and its PDF changes with the system statement.

    Thus, I want to use the BER calculation by error counting instead of BER estimation. Moreover, the experimental BER level is around 10^-5. However, it seems the common method to calculate the BER is based on the PDF estimation.

    How can I calculate the error by direct error counting? I set up a simple system model in the attachment.

    Could anyone give me some advice?

    Mohamed Atef · Assiut University

    This method described by Bruno is not accurate with strong ISI and non-Gaussian noise. The number of errors should be counted to get a correct BER.

  • I am looking for some well-known papers or reviewed papers on tradition and existence improvement dynamic behavior soil methods?

    For example what sort of methods engineers used in the past and now what?

    Because I need to prepare a overview paper on dynamic behavior of soil and improvement methods.

    Johnatan Ramos Rivera · National University of Colombia

    Dear Sayed,

    Check the following links:





  • Rebecca Stanhope asked a question in PCR:
    Adding attB into my plasmid?

    I'm a long time reader of this forums and a first time poster. I have a plasmid with my gene of interest on it. It is on a pGEM backbone with ampicillin resistance marker. My gene of interest is AT-rich. I am trying to put an attB sequence into the gene. The plasmid is about 8kb. I have tried whole plasmid PCR with overlapping attB sequence on the 5' ends of the primers, but did not get amplification. I have also tried to split the plasmid into two sections for gibson assembly, but i could not amplify either section. (one was 1.4kb and the other was 6.6kb). I'm at my wits end and am looking for any suggestions! I have tried many different pcr conditions, dna concentrations, and mg2+ concentrations. I have done an annealing gradient pcr and even an extension pcr. I appreciate any help you can give!

  • What are the Aspectual Verbs?

    I am looking for a list of aspectual verbs that could be applied to Old Indo-European Romance languages. I know that 'to begin, to finish, to  stop' are common aspectual verbs cross-linguistically. However, I have seen verbs, like 'attempt, try, intend' also listed as aspectual verbs. What are the best criteria to assign this category? Thank you!

    Simon Kasper · Philipps University of Marburg

    Also Croft's (2012) "Verbs. Aspect and Causal Structure." He distinguishes between aspectual differences contributed by the clause/construction from those contributed by the verb.

  • What method can we use to control coffee borer beetle (Hypothenemus hampei) in organic coffee plantation?
    Growing coffee organically, what solutions aside from applying Mycotrol, Garlic Barrier and setting ethanol/methanol traps, can you use?
  • Is injection of ions from an electrospray source inefficient if performed through the ring electrode?

    Most of the designs of Paul traps I've seen have holes in the end caps to inject ions through. Can't injection be efficiently performed when done through an octapole ring electrode?

    Vladimir Montero Collado · University of Manitoba

    Got it. Another question: What do you mean by octapole ring electrode? An octapole transmitting the beam to the inside of the trap through an orifice in the ring electrode?

  • Lale Evsen added an answer in Dissection:
    What I can use for chick embryo dissection in ovo (stage 8-11) if I don't have fine dissection needles (1 um tip)?
    I need to graft from one chick embryo to another. I feel my tungsten needles (hand sharpened) are too dull to do it. I can prepare grafts in a plate, but I can't prepare embryo for grafting. Fine needles will not be here (UK) soon.
  • F. Caballero-Briones added an answer in PEDOT:PSS:
    Does Ag NPs have negative effect on BHJ solar cells efficiencies (to be used as buffer layer)?

    I am working on Ag NPs/graphene composites which have work function 5.6 eV and acceptable conductivity. I used it as hole transfer material to replace PEDOT:PSS. But i faced with low FF in compare to PEDOT:PSS samples.

    F. Caballero-Briones · National Polytechnic Institute-CICATA Altamira

    My guess is that Ag NPs are working as hole recombination centers

  • Does transformation of microfinance institutions into regulated financial institutions increase accessibility of financing to the low income class?

    Most microfinance institutions were founded as non-profit organizations with main mission of providing financial services to the low income class or financially excluded people, mostly women. Although, it appears that transformation of microfinance institutions into regulated financial institutions comes with many benefits such as influx of new capital, deposit mobilization, increase outreach and improved management and governance among others. There is fear that transformed microfinance institutions may deviate from their original mission to serve the low income class and alleviate poverty. More specifically, some observers believe that the transformation of microfinance institutions into regulated financial institutions may encourage profit motive over social impact of alleviating poverty.

    John Agyekum Addae · Ghana Telecom University College

    As evidence of MFIs social mission  drift to commercialization, the average loan size normally increase.

  • Kyrylo Greben added an answer in Sputtering:
    How safe to sputter PZT target at room temperature? Or any document/article specifying safe parameters for PZT sputtering?

    I am looking for document or article saying PZT sputtering at these parameters are safe.

    Kyrylo Greben · Forschungszentrum Jülich

    Hi Ajay,

    Why shouldn't it be safe? It is more dangerous to do it at high temperatures as people (and you probably also) usually do.

    The difference will be that your film can fail growing, because the temperature is needed for the cell formation. However, if you try to achieve the growth at room temperatures, I think you can give it a try and don't worry about the target, unless there is something that you didn't mention or there are special conditions.



    P.S. Sorry, no publication for you.

  • Uriah Alexander Lar added an answer in Petrology:
    How does one explain the presence of a crustal rock with mantle signature in an Alpine Peridotite Massif?

    A rock sampled from an Alpine peridotite massif was petrologically referred to as gneiss (consisting of amphiboles, plagioclase, and quartz with accessory zircon). Geochemical analysis of the rock revealed the composition of SiO2 =75.41, Al2O3=14.01%, Fe2O3=0.59%, CaO=1.55% and Na2O=6.92 wt% (indicating a crustal origin), but the isotopic composition in 143Nd/144Nd=0.512989 indicating a mantle origin. However, its REEs spectrum differs from that of a typical crustal rock by displaying significant enrichment in LREE relative to HREE.

    Uriah Alexander Lar · University of Jos

    Thanks for your immense contributions. To answer some of the questions posed, the Sr isotopic composition of the rock : 87Sr/86Sr=0.704737. The rock was sampled at the contact between the host gness basement and the peridotite massif. The contact rocks are as deformed as the host gneiss basement (concordant foliations). No evidence of fluid activity was observed, but that cannot be ruled out in such a geodynamic setting (subduction zone).

  • How do you predict drug-drug interactions?

    Is there a computer program for predicting drug-drug interactions? Who can supply this?

    Manuela G Neuman · In Vitro Drug Safety and Biotechnology

    The data bases and the monogrames give the answer to logical and possible drug-drug interactions or drug chemical known interactions. However there are rare idyosincratic reactions and interactions that are limited to a small number of individuals sensitive to one therapeutic pr a combination of drugs. To identify the drug to which the specific individual reacted with an adverse event you need to perform in vitro lymphocyte toxicity assay(s)

    Neuman MG, Malkiewicz IM, Shear NH. 2000. A Novel Lymphocyte Toxicity Assay to Assess Drug Hypersensitivity Syndromes. Clin Biochem. 33(7): 517–524.

  • Johnatan Ramos Rivera added an answer in Solid:
    Is there any information about construction of earths live model ?

    Explaining about solid layer in center & upper part and middle occupied by the filled liquid whose temperature where no solid can exist.

    Johnatan Ramos Rivera · National University of Colombia

    Dear Govind,

    Please can you give more specific details about your question and the term "Earths live Model?

  • Jeffrey Craig asked a question in Infographics:
    What do people learn from viral statistics presented as infographics?

    One common way in which information that goes viral through Web 2.0 media is through infographics.  I am looking for research that addresses representational differences in statistics, with a specific focus on infographics that use multiple representational forms.  I also want to find research involving viral media learning, including interaction between knowledge, beliefs and identity.

  • Lale Evsen added an answer in Chick Embryo:
    What is the best way to get HH10 embryos during normal working hours?
    According to Hamburger and Hamilton stages of chick embryo development (HH), HH10 occurs at 33-38h of egg incubation. Hence, to get HH10 from 11am to 4 pm, one should start eggs incubation around 2 am (or vise versa). The temperature of incubation is 37.8-38 C. Does anybody know the way (e.g. lower incubation temperature) that will slow down the embryo development, but will not affect it? Does anyone know the equipment that will allow you to turn on incubation at night automatically? We have the Octagon 40 Advance EX Incubator with cooling function (above 20 oC only).
  • Simon Kasper added an answer in Philosophy:
    Has the philosophical analysis contributed to solve any biological conceptual problems?

    Of course the first question would be how many conceptual/empirical problems, of philosophy's interest the biology has? How many of those problems has been solved? 

    Just in case of any extremist response, what would you say to a biology scientists who thinks that the philosophy cannot solve anything?

    Simon Kasper · Philipps University of Marburg

    Philosophy (of Science) formulates conditions on the possibility that biology solves problems. That is why it is philosophy, not science.

  • Leszek Jurdziak added an answer in Natural Gas:
    Can natural gas be considered as an effective alternative to mitigate climate change?

    In general, can the increased natural gas usage along with implementation of advanced technology for gas production slow the growth of greenhouse gas emissions by 2050?

    Can natural gas be considered as an effective alternative to mitigate climate change?

    Leszek Jurdziak · Wroclaw University of Technology

    Each year China increases coal burning 1.5 times more than the whole Poland production.