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  • What does the term “Research Culture” mean to you?
    When we discussed about Research Culture, I saw this is an interesting topic that researchers have different opinions about it. Please share your opinion with me.
    Is there any dos and don'ts in research? Is the term Research Culture in existence? Is it positive? Does it have any negative facet?
    Arno Gorgels · Principia Naturae

    Interesting

  • How do we create virtual electrical elements in electronics? Are they really "elements" or circuits?

    To build electronic circuits, first of all we need the natural electrical elements resistors, capacitors and inductors. However, in many cases we are not satisfied with the performance of these passive components and try to improve them in an artificial way. For this purpose, in electronics we have invented a variety of clever and sophisticated techniques to create artificial (synthetic, virtual) elements. The question is, "How do we make virtual elements?"

    Like magicians, in electronics we convert the imperfect passive elements into perfect active "elements" (by applying the virtual ground configuration)... or we transform some element (a capacitor) into its dual (an inductor) by swapping the voltage across and the current through it (gyrators)... or we transmute the passive circuits into their opposite mirror doubles (negative impedance)... or we even create completely new electrical elements (memristors)... Thus, for some reasons, we frequently replace the natural electrical elements by their circuit equivalents - a gyrator, multiplier, memristor, negative resistor (capacitor, inductor...)

    It is important to note that all these virtual "elements" (electronic circuits) emulate only particular properties (usually, the time behavior) of the genuine elements... they are not real, they are just an illusion...

    Genuine elements. The general property of passive electrical elements is taking (consuming) energy from the input source; resistors dissipate this energy while capacitors and inductors store (accumulate, "steal") it. But how do they do it?

    Let's assume the considered passive element is connected in series to the exciting voltage source. What does it do in this case? It subtracts a portion of voltage from the whole input voltage: the resistor "creates" an opposing voltage drop across itself while the capacitor and inductor "create" an opposing voltage (a kind of emf). Resistors do this by throwing out (dissipating) energy while capacitors and inductors do it by taking energy from the excitation source, accumulating it into itself and setting it against the input source. In the first case there is a voltage drop while in the second case there is a voltage (emf).

    So, we can emulate these passive elements by replacing them with some other elements producing the same opposing voltage (having an opposite to the input voltage polarity when travelling along the loop). Then, we can modify or even create mirror active (negative) "copies" of these passive elements by replacing them with sources producing the same but now "helping" voltage (having the same as the input voltage polarity when travelling along the loop). This is the main idea of the substitution and inverse substitution theorem perfectly considered by Prof. Lutz von Wangenheim in his work: 
    https://www.researchgate.net/file.PostFileLoader.html?id=540dd638d039b1ee348b458f&key=d62e286c-fe94-4019-b22b-4b550b6c8bfa

    * Emulating by (varying) voltage. First, we may replace the original elements by varying voltage sources and this is the most natural way of making emulated capacitors and inductors (as they behave as varying through time voltage sources). Op-amp gyrator, multiplying, memcapacitive and meminductive circuits do it in this way. In these circuits, the op-amp output voltage represents the voltage across the according capacitor or inductor.

    In the case of the true negative resistor, the ordinary ohmic resistor is replaced again with a voltage source (exactly as in the case of gyrators and multipliers) but it has the same polarity as the input voltage source so that it adds an additional  voltage to the input voltage. For example, the negative impedance converter with voltage inversion (VNIC) is a dynamic voltage source emulating a negative resistor by adding a voltage that is equal to the voltage drop across a real ohmic resistor.

    It is interesting that we can change the properties of the ordinary constant voltage source by  properly varying its voltage (as in the attached picture below).
    The emulation by including an additional voltage source is the basis of the Miller theorem (see https://en.wikipedia.org/wiki/Miller_theorem#Applications).

    * Emulating by (varying) resistance. But a memristor can do the same by replacing the voltage by an equivalent voltage drop across a dynamic time-dependent resistor. Transistor gyrator and multiplying circuits do it in a similar way.

    It is interesting that we can change the properties of the ordinary ohmic resistor by properly varying its resistance. A good example of this technique is the creation of the negative differential resistor:
    https://en.wikibooks.org/wiki/Circuit_Idea/Negative_Differential_Resistance#General_considerations_about_creating_the_NDR

    So, to emulate passive elements (to create virtual elements), we may replace the elements behaving as resistors with (properly varying) resistors, and elements behaving as sources - with (properly varying) sources. But it seems we can do it by swapping these correspondences - replacing the elements behaving as sources with resistors, and elements behaving as resistors with sources... Am I right? Please, discuss.

    ------------------------

    I was inspired to ask this question mainly by the numerous discussions between me and Prof. Lutz von Wangenheim mostly in the questions below...

    https://www.researchgate.net/post/Are_electrical_sources_elements_with_static_negative_impedance_If_so_is_there_any_benefit_from_this_concept

    https://www.researchgate.net/post/Does_the_op-amp_in_all_the_inverting_circuits_with_negative_feedback_behave_as_a_negative_impedance_element_negative_resistor_capacitor_etc

    https://www.researchgate.net/post/Does_the_amplifier_in_negative_feedback_systems_possess_negative_impedance?

    ...and especially, by his idea about the inverse substitution theorem (IST) proposed by him in the question below:

    https://www.researchgate.net/post/Can_we_formulate_Kirchhoffs_laws_for_resistances_KRL_and_conductances_KGL_based_on_KVL_and_KCL/2

    Cyril Mechkov · Technical University of Sofia

    7. Virtual infinite resistance (2-3). Let's then apply the modified Miller's idea to make virtual infinite resistance in such a marvellous manner as we made virtual zero resistance above. So imagine when you reach the point 2 (the attached picture below), I decide to oppose exactly you along the whole section 2-3. You continue increasing (make more positive) the voltage VIN of the input voltage source from point 2 to point 3 so that its IV curve continues translating to the right. But now I begin vigorously increasing the voltage VO so the composed VO-R IV curve quckly moves (translates) to the right as well. As a result, the operating point A slides along a new horizontal IV curve, which represents the new virtual infinite resistance dR2 = ∞ and you have the illusion the resistance R has become infinite...

    We can see this clever trick in the Ohm's equation - I = (VO - VIN)/R. In the numerator, the two voltages change with the same rate and direction; so, their difference and respectively the current, stays constant.

    This great idea is known as bootstrapping. It may be observed in perfect op-amp voltage followers. It is frequently used in amplifiers and constant current sources to increase extremely their input impedance.

  • Thomas Andl added an answer in Paraffin:
    With sections embedded in paraffin, is it possible to do immunofluorescence? Would you obtain a good resolution of a double-labeling?

    I have several brain sections embedded in paraffin and I want to do double-labeling with immunofluorescence but I do not know if the resolution of the staining will be correct for the count. 

    Thomas Andl · Vanderbilt University

    A good starter to read if one is not sure what the primary antibody is doing is this article:Griffiths G1, Lucocq JM: Antibodies for immunolabeling by light and electron microscopy: not for the faint hearted. Histochem Cell Biol. 2014 Oct;142(4):347-60. doi: 10.1007/s00418-014-1263-5. Epub 2014 Aug 24. I found this through Researchgate!!! This is an honest summary of the quality of antibody stainings, what to do to make the situation better, and what to be aware of. And it has interesting references within.

    Basically it gives you an idea how bad things are with antibodies. I have seen many dubious publications where stainings were basically "background" or better false positive staining. And you can read many comments on Researchgate about bad antibodies and bad antibody sellers.

    I assume you know where your antigens are expressed (nucleus, membrane etc). Then you can expect that the antibody stainings are restricted to these subcelluar structures. If your primary antibody produces "background" then there is very little you can do except reabsorb it versus the background epitope. I have seem many polyclonal rabbit sera that like to bind to keratins and this will "overshadow" the good antibodies in the serum.

    You can try to use ordinary blocking that in a perfect world should be a useless reagent since you often block with something like BSA . That will not fundamentally make a bad antibody good unless miraculously the "background epitopes" are in the blocking solution. Very unlikely. Blocking for IF is probably one of the most overrated procedures.

    You can try to vary your antigen retrieval in the hope that the background will not be activated by certain methods. I never tried this but it may be worth the effort if there are no alternative antibodies available. Since you intend double-stainings this may not be an option.

    I hope I understood your info correctly and my comments will be helpful.

  • How to carry out the work Up of Iron-H2SO4 assisted reduction?

    I reduced the Dinitro containing compound in the Iron H2SO4 and now I want to isolate the product.

    Dieter Sicker · University of Leipzig

    You should say what dinitro compound you tried to reduced to what (expected) diamine, if you may say that.

    Discussing about "green" is useless if there is no more information.

    And whre is the green? In aqueous solution? or in organic? if so, in what organic solvent?

  • Ufuk Turen asked a question in Academic:
    What are the most important criteria for academic institutions in recruiting academic personnel?

     What aspects should be considered more important for academic personnel, especially for young researches in career planning? What are the most important attributes of a successful academician?

  • How I can test the control variabls such as age and gender in Regression Analysis

    Hello mu friends - I HAVE A SET OF INDEPENDENT VARIABLES AND THE LIKERT SCALE WAS USED ON THEM AND I HAVE ONE DEPENDENT VARIABLE AND THE LIKERT SCALE WAS USED AS WELL. I MADE THE ANALYSIS AND I WANT TO BE SURE THAT I'M DOING THIS WRITE - HOW I CAN USE CONTROL VARIABLES SUCH AS AGE AND GENDER AS CONTROL VARIABLES TO MEASURE THEIR EFFECT ON THE RELATIONSHIP BETWEEN THE INDEPENDENT VARIABLES AND THE DEPENDENT VARIABLE?

  • How can I plot recrystallization kinetics after double compression test?
    I wish to know how to curve fit recrystallized fraction against time using the avrami equation in order to get a sigmoidal curve. Please see attachment.
    Goran Vukicevic · ZELEZARA SMEDEREVO d.o.o.

    It is important to know which method is used for determination fractional softening from double compression test results i.e 0.2 offset, mean flow stress or back extrapolation method ? This is important because it measured fractional softening  does not equal the recrystallized fraction. For example its shown that in the case of 0.2% offset method, 20% measured fractional softening corresponding to recovery and that recrystallization starts after that.

  • Translation of medical articles for a systematic review

    I am doing a systematic review and meta-analysis on immunotherapy. Some non-English articles (articles in Chinese, french and Spanish) are included in my search results.

    As I am not familiar with these languages, I faced a problem with extraction of data from these articles.

    Does anybody have any advise on how to extract data from these articles?

    Is there any free translation services for these languages?

    Unfortunately, online translators like Google translate does not provide an accurate result considering these articles include medical terms.

  • What is the best internal control for Nicotiana tabacum?

    I'm doing RT-PCRs. Which gene is considered a good internal control for tobacco?

    Madhurima Kahali · University of Delhi

    thanks Alexander, I'm using ubiquitin..but not too sure if it's the best one

  • Sha Anwer Kakil added an answer in Zno Thin Films:
    What might be the reason for difference in density of ZnO thin films deposited on 2 different substrates under similar conditions?

    I am using reactive dc magnetron sputtering and substrates are glass, acrylic. desity was lower on glass.

    Sha Anwer Kakil · Salahaddin University - Hawler

    dear kumar the substrate effect on the deposition thin film

    also depend on band gap of substrate  and lattice mismatch

  • Louis Brassard added an answer in Music:
    How does music affect our feelings?

    Music interferes with our feelings, enjoyment and to some extent may be a therapeuticc option. Music accompanies most of, if not, all our ativities. What are the effects of music in our nervous system? How do we respond?

    Any views are welcome 

    Thanks Marwan for the references. 

    ''Caregivers also speak to infants in a special, singing manner, so-called ‘baby-talk’ or
    ‘motherese’ (see Bunt & Pavlicevic, this volume). Nevertheless, infants seem to discriminate between infant-directed speech and infant-directed music. Trehub (2001) reports a study in which 6-months-old infants viewed videotaped performances of their own mothers (recorded while singing or speaking to their infants). The infants showed more sustained attention to mothers’ singing episodes than to their speaking episodes. Infants were ‘hypnotised’ by these sung performances, remaining ‘glued’ to the monitor for extended periods. Mothers’ speaking was not as engaging as their singing.''

    http://www.brams.umontreal.ca/cours/files/PSY-6441/EmotionMusicales/999Peretz2001Chapter.pdf

    This sustain me in the hypothesis that singing-dancing was our first language.

  • How is the band gap of CuS?
    I see that in some articles band gap is direct and in other articles, it is indirect.
    Would you please explain it? Which is correct?
    Leonid A. Skvortsov · Polyus Research & Development Institute

    With an increase the sulfur content the resistivity of the copper sulfide samples decreases and there is a transition from a high-resistance semiconductor Cu2S to CuS with metallic properties. The bandgap of the material according to published data ranges from 0,6eV to 2,35eV to [1], and depends on the crystal structure.
    1. H.M.Pathan, J.D.Desai, C.D.Lokhande, Appl.Surf.Sci., 202 (2002) 47.

  • Muge Atis added an answer in PCR:
    Wrong template but have a reasonable PCR product?

    Can it be possible to have a PCR product from a wrong backbone? Primers of that PCR protocol were designed with respect to backbone sequences downloaded from a database. However, we realised that our backbone is not completely a match with its original sequence (we sequenced our backbone) and there are lots of point mutations on it. How can we still have a PCR product if our backbone doesn't match the sequence that we design primers from there? Can it be because of high GC % of my primers which are over 60%? Thanks in advance.

    Muge Atis · Koc University

    Thank you all for your answers.Dear Maureen,my template is plasmid DNA and there are more than 10 point mutations which is seen that the sequence had totally changed.

  • Can anyone help me correctly identify this plant?

    Elevation ft: 1800-2500
    Semi Arid zone
    North Gujarat Region, Gujarat, India.

    I've shown only one patch in this forest region

    Laurentius Josephus Gerardus van der Maesen · Naturalis Biodiversity Center

    To me this looks more of a Zantedeschia or Calla, but those Araceae do not occur naturally in India. Of course when flowering more can be said.

  • D.P.S. RATHORE added an answer in Research Papers:
    In writing a research paper, is it required that we state the reliability and validity of the research instrument we used?

    For new instruments used? For instruments that we re-used?

    D.P.S. RATHORE · Atomic Minerals Directorate for Exploration and Research

    Each instrument differ in Performance Qualification (PQ) as discussed in a review paper. Moreover, the reliability/quality of measurement results depend strictly on adherence to each step of measurements of the method and not simply analysed by any person or lab or any technique/instrument.

    Interpretation and conclusions based on such unreliable analytical results  will be highly misleading.

  • How has electronic charting changed critical thinking and decision making in your practice?

    It is mandated that electronic medical records are required to guide patient care in all institutions throughout the U.S. by 2014 with the premise that this will enhance communication between caregivers and decrease medical errors.

  • Eloise Collins asked a question in Self-report:
    Questionaires

    where can I find self-report surveys to test behaviors/personality?

  • Can any one help to select the good clustering algorithm that deals with the clusters shapes and sizes please?

    Clustering Algorthim

    Mehdi Ebady Manna · University of Babylon

    Thanks all for replies and comments

  • Have you experienced a case of a very high, unexplained and asymptomatic rises of serum CPK?

    A patient suffering from psychotic disorder treated with low dose clozapine (150mg/day) experienced a very high, asymptomatic raises of serum CPK (up to 40 000). No symptoms of neuroleptic malignant syndrome. Any suggestions?

    Tomasz Sobow · Medical University of Łódź

    no statins. i am aware of this possibility, but not in this case

  • Saleh Alkarim added an answer in Breast Cancer:
    Which CD marker would be used for selecting fibroblast cells in an in-vitro culture?
    Which CD marker is specific for fibroblast cells and epithelial cells?
    Saleh Alkarim · King Abdulaziz University

    Hello

    Fibroblasts are cells that form the connective tissue. They can differenciate into distinct connective tissue cells and maintain the extracellular matrix of the fibrous connective tissue.

    There are a large number of surface markers you can use them , ( Vimentin ;
    SFA ; CD34 ; FSP1;Prolyl-4-Hydroxylase ; ER-TR7 ; PDGFR-alpha ) I'll explain to you :

    Vimentin ; is the most frequently found intermediate filament in fibroblasts 

    SFA : is a glycoprotein produced by connective tissue cells e.g (mesenchymal cells, fibroblasts, and astroglia cells) that is also suited for detection of fibroblasts and fibroblast cell lines.

     antigen CD34 is a good choice ,where there is in human hematopoietic progenitor cells , It is distributed in most connective tissues, among them alveolar connective tissue and the connective tissue of skin and blood vessels. A marker for fibroblast differentiation in the human dermis are endogenous peroxidases it can also be used to mark skin fibroblasts

    Fibroblast-specific protein 1 (FSP1) can be detected in mice as early as day 8,5 p.c. It occurs in the cytoplasm of fibroblasts, but not in epithelial cells. Rarely, FSP1 antibodies will react to the parenchym. In case of inflammation, epithelial cells are marked by FSP1 antibodies, too, which are thus assumed to be converting to fibroblasts at the site of inflammation.

    For activated fibroblasts, we recommend procollagen type 1 or Prolyl-4-Hydroxylase beta antibodies, the latter occurring in epithelia, endothelia, alveolar macrophages and in interstitial cells.

    They express ER-TR7, intracellular components which are thus very practical to use for marking such fibroblast types.

    PDGFR-alpha is a specific marker of fibroblasts .


    Ref : (Strutz ,F. et al. 2004 ; K. Kuroda und S. Tajima, 2004)

    Best wishes

  • Method TBARS protocol

    Protocol to analyze MDA (TBARS method) in serum of rats? Can anyone help me with a protocol for serum TBARS of rats! Thanks

    Hilana Rickli Fiuza Martins · Faculdades do Centro do Paraná

    Hi Tiago! How can I do this? Can you send me a paper so I can know these methods? Thank you! 

  • Saleh Alkarim added an answer in Fibroblast:
    IHC - Characterization of Mouse Tail Tip Fibroblasts - can anyone help?

    I have just isolated some tail tip fibroblasts from very young (1-wk old) mice for experimentation. I am using IHC to confirm the identity of the fibroblasts.

    I have looked at a few Q&A topics on ResearchGate and also some papers for some good surface markers. So are there any other markers besides Vimentin, FSP, SFA, TE-7, CD34, that generally stain fibroblasts (with a lot of exceptions), that can be more specific to identify my cells as Tail Tip Fibroblasts.

    Also I am so confused about CD34, isn't it staining stem cells? Or tail tip fibroblasts are multipotent? Okay I am really confused now...

    Thank you for any advice or suggestions.

    Saleh Alkarim · King Abdulaziz University

    Hello 


    Fibroblasts are cells that form the connective tissue. They can differenciate into distinct connective tissue cells and maintain the extracellular matrix of the fibrous connective tissue.
    for surface markers you have a good choice , and I'll explain to you :

    Vimentin ; is the most frequently found intermediate filament in fibroblasts .
    SFA : is a glycoprotein produced by connective tissue cells e.g (mesenchymal cells, fibroblasts, and astroglia cells) that is also suited for detection of fibroblasts and fibroblast cell lines.

    for antigen CD34 is a good choice and i am agree with Célimène Galiger ,where there is in human hematopoietic progenitor cells , It is distributed in most connective tissues, among them alveolar connective tissue and the connective tissue of skin and blood vessels. A marker for fibroblast differentiation in the human dermis are endogenous peroxidases it can also be used to mark skin fibroblasts

    Fibroblast-specific protein 1 (FSP1) can be detected in mice as early as day 8,5 p.c. It occurs in the cytoplasm of fibroblasts, but not in epithelial cells. Rarely, FSP1 antibodies will react to the parenchym. In case of inflammation, epithelial cells are marked by FSP1 antibodies, too, which are thus assumed to be converting to fibroblasts at the site of inflammation.

    For activated fibroblasts, we recommend procollagen type 1 or Prolyl-4-Hydroxylase beta antibodies, the latter occurring in epithelia, endothelia, alveolar macrophages and in interstitial cells.

    To detect myofibroblasts, the anti-alpha-actin antibody with the clone designation 1A4 from smooth muscle tissue can be used.

    They express ER-TR7, intracellular components which are thus very practical to use for marking such fibroblast types.


    Ref : (Strutz ,F. et al. 2004 ; K. Kuroda und S. Tajima, 2004)

    Best wishes

  • Joseph L Alvarez added an answer in Momentum:
    How is it possible to have momentum in a situation of perfectly static electric and magnetic fields?

    The Poynting vector P  = E X H is non-vanishing for a perfectly static situation like a charged capacitor with a magnetic field applied perpendicular to the electric field between its plates.

    How can static fields carry momentum? Either our understanding of fields is wrong or we have to redefine momentum!

    Joseph L Alvarez · Alpha Beta Gamut

    Hanno, Rajat, Read Feynman carefully, including the magnet and charge later in 27-6. Angular momentum is imparted to the capacitor and must be conserved. There is no energy flowing into or out of the system, but the system has energy and momentum.

  • Chandan Maity added an answer in Computer Science:
    How do you turn a graph into a string(of {0,1})?

    I want to know how could i represent a graph using a string; i mean the string should contain all the information to reconstruct the graph(not exactly the original one if it's not feasible but maybe a similar graph) of course.

    Hassan,

    The "String" is kind of high level word in the world of traditional languages. It could be represented by a character array or int array or long array....so on.

    Idid not exactly understand the importance of {0,1} inside the string. Are you not wasting a lot of space ?? Can you elaborate the exact problem statement? Why do you need a string, not any other keywords ? Are you implementing something where the API recognizes only String such as File_Read or data_read/write etc?? If it is the situation, there are huge alternatives and the first one is : read in binary mode, so you never require a STRING.

    However, Let me give some crude method that may help you to get resolve the problem without going inside deeper mathematics.

    First, design the data-structure format of your container:

    For graph, get basic Static parameters : Resolution, scaling, offset (if any) , units etc and put inside Header. You can store dynamic data inside Data segment. Starting and delimiter parts are optional.

    The data format can be:

    Header (Static params): [Resolution (1 Byte), Sample rate/sec (1 Byte or more), X-unit (Fixed bytes), Y-unit (Fixed Bytes)

    Data (Dyn params): X-data1(X bytes as defined in header), Y-data1 (X bytes as defined in header), X-data2(X bytes as defined in header), Y-data2 (X bytes as defined in header)...................................

    *If you are passing Sample rate, either X or Y parameter may be enough.

    X-data1(X bytes as defined in header), Y-data (X bytes as defined in header)

    All those data can be easily stored inside a char array or int or double array. 

    If you really need a STRING, just check individual bits and set as 0 or 1 in the string. though it is a worst way of implementation.

  • Gabriela Dornikova added an answer in MIC:
    Disk diffusion technique is still a valid technique for studies of antimicrobial susceptibility?

    I would like to read opinions about this. Because most of the studies use other techniques, using MIC, to assess the antimicrobial susceptibility? Is there a restriction from CLSI to use disk diffusion on this?

    Gabriela Dornikova · Our Lady Of Lourdes Hospital, Drogheda, Ireland

    Disk diffusion test is still a valid technique. It is described in details in both Guidelines used in Europe - BSAC and EUCAST. In general,   it would not be recommended for  anaerobic bacteria and fungi.

  • Why am I getting different localisation patterns between animal tissue and cell culture?

    Our protein shows an apparently different localisation pattern between cultured cells and animal tissues. IF-staining of HeLa, SHSY5Y and primary skin fibroblasts are both nucleolar and cytosolic with the same distribution for GFP-tagged protein in living HeLa. However, IF and IHC with paraffin embedded mouse tissue shows only cytosolic and no nucleolar localisation.

    The antibody recognizes both human and mouse. Same for a homologous isoform using a different antibody: If nucleolar and cytosolic in cultured cells, but only cytosolic in mice tissue. No idea what the protein's function actually is, but it binds RNA and it can be isolated from the nucleus in complex with splicing factors, so nucleolar localisation would not sound artificial. In cell culture, the protein also seems to exit the nucleus upon generic stress (heat, oxidation, intoxication), which suggests some sort of shuttling properties. Any idea of what might have happened? Methodical artifact? Metabolic issues of cultured cells? 

    Steingrimur Stefansson · HeMemics Biotechnologies Inc

    Hi Fabio, I was working with NPXY receptors and there is a huge difference in their localization in tissues compared to cell lines.

    I could never find any explanation for this, but it might be due to the radically different cell environments.

    Additionally, cell lines are selected for their ability to grow as a monoculture and often what they express and how they express it can't be compared to their in vivo counterparts.  

  • Abhijit Khadke added an answer in Values:
    How the summation of dBm units gives the value in dB units?

    For example -3dBm+30 dBm=27dB

    Abhijit Khadke · R. C. Patel Institute of Technology

    Sorry Tolgahan ok these are not units right but why they write summation of dBm as dB

  • What is your opinion/experience on a universal intrapartum GBS screening strategy using a rapid real time testing followed by IAP in positive cases?

    To facilitate a consensus towards European guidelines for the management of pregnant women in labor and during pregnancy for the prevention of GBS perinatal disease, a conference was organized in 2013 with a group of experts in neonatology, gynecology-obstetrics and clinical microbiology coming from European representative countries. The group reviewed available data, identified areas where results were suboptimal, where revised procedures and new technologies could improve current practices for prevention of perinatal GBS disease. The key decision issued after the conference is to recommend intrapartum antimicrobial prophylaxis based on a universal intrapartum GBS screening strategy using a rapid real time testing.  Di Renzo GC, Melin P, Berardi A, Blennow M, Carbonell-Estrany X, Donzelli GP, Hakansson S, Hod M, Hughes R, Kurtzer M, Poyart C, Shinwell E, Stray-Pedersen B, Wielgos M, El Helali N. Intrapartum GBS screening and antibiotic prophylaxis: a European consensus conference. J Matern Fetal Neonatal Med. 2014 Aug 27:1-17. [Epub ahead of print].  

  • Tushar Ray asked a question in Topology:
    Can anyone identify the Na-pump regulatory protein (NaAF) from the proteomics or genetics data bank?

    The NaAF (~170 k Da mass) acts as the cytosolic regulator of the ubiquitous Na-pump in all animal cells.  The closely related gastric Proton-pump (of same P2-ATPase family) is regulated by an isomeric HAF of 80 k Da mass, has similar domain structure as the NaAF.  The similarities in domain structure were revealed from studies on cross-activation of the Na, K-ATPase and H, K-ATPase by individual activators.  

    We firmly established the relation between the HAF (known amino acid composition) and H, K-ATPase using an anti-HAF- antibody. The monospecific antibody raised against pure and homogeneous preparation of HAF strongly inhibited the H, K-ATPase function in both isolated gastric gland in situ as well as gastric microsomes in vitro showing the reliability of our data. The details on the regulation of gastric proton-pump and ubiquitous Na-pump were published in dozens of papers (in refereed journals in the 80’s). Our data revealed the inadequacy of the popular Post-Albers model of Na-pump dominating the field for 50-years. Since we were ahead of the time our hard evidence was ignored until very recently.  

    The quest for structural information on NaAF and HAF from existing data bank, if realized, will rejuvenate this vital ion-pump field. Since I do not have expertise on data-banks analysis, I am looking for some experts to revitalize this critical field. To this end I am excited on the prospect of sharing our published and unpublished data along with my skill.

    Also, I am looking for some expertise in preparing a dual topology (mirror-image) model from the existing single topology one available in the literature.

  • Spyridon Methenitis asked a question in Muscle Fiber:
    Muscle Fiber Conduction Velocity at rest and during contractions

    Hello every one

    I am doing my PhD thesis, and i would like to ask if muscle fiber conduction velocity, evaluated ata rest, is correlated with those evaluated during contraction. Please if you have any paper for this it will be very helpful