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  • Bhoj R Singh added an answer in Bacterial Transformation:
    What selectable markers can one use for bacteria other than antibiotics for various purposes?

    Specify for transformation,curing of plasmids,for pseudomonas,E.coli etc.?

    Bhoj R Singh

    Selection of markers depend on your study purpose and design, there are several visible / detectable biochemical characteristics, resistance to dyes, heavy metal salts, growth patterns etc. To read more you can see chapter 6 & 8 of the book at the following link.


    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: The genetic material of bacteria and plasmids is dsDNA but of bacteriophages it may be dsRNA, dsDNA, ssRNA, or ssDNA. The two major and essential functions of genetic material are replication and expression in all organisms. Microbial genetics means genetics of microbes (bacteria, Archaea, viruses, including bacterial viruses i.e., bacteriophages and unicellular or mycelial eukaryotes including yeasts, other fungi, algae and protozoa). Microbial genetics has applications in medicine, veterinary, agriculture, food and pharmaceutical industries. Because of simplicity in physiology microbes have been exploited for understanding interaction of biochemical, physiological and genetic components of the life. It has successfully furnished details of genetic code and the regulation of gene function. Besides, microbes being both useful and pathogenic, genetic studies have helped in understanding pathogenesis of infectious as well as genetic and non-infectious diseases, and variability in pathogens. The first chapter on microbial genetics started by George W. Beadle (1903–1989) and Edward L. Tatum (1909–1975) while investigating genetics of tryptophan metabolism and nicotinic acid synthesis in Neurospora, a fungus postulating the "one gene one enzyme" hypothesis. However, studies on bacterial genetics started in 1947(Joshua Lederberg) with demonstration of exchange of genetic factors in Escherichia coli through conjugation, mediated through plasmids, “fertility factors”. Later on process of transformation, transduction and chromosomal gene mobilization lead to genome (chromosome) mapping in bacteria. These techniques combined with restriction enzyme analysis lead to sequencing, cloning and expression of several genes (prokaryotic and eukaryotic) in microbes. There are nine chapters in book on different aspects of microbial genetics including bacteriophages and transduction, plasmids and conjugations, mutations and mutagenesis, transformation genetics and bioinformatics.
      First edited by Bhoj R Singh, 01/2010; Lambert Academic Publishing, Germany., ISBN: 978-3-8383-2748-8
  • Jisoo . Lee asked a question in DNA Polymerase:
    How can you check if the DNA template used for PCR was contaminated or not?

    The PCR outcome turned out negative and two reasons were suggested:

    1. DNA polymerase used was expired

    2. DNA template was contaminated

    is there a possible experiment to confirm these two hypotheses?

  • Vivek J Vyas added an answer in Encryption:
    Can anyone recommend an encryption simulator?

    Can anyone suggest me an encryption simulator?

    Vivek J Vyas

    gm respected AR Reddy sir,

    sir i want to start my research work so from where to start in this area of developing and simulating performance.

    sir can u guide me in this regard.

    my email id is vyasvivekj@gmail.com.

  • Paulo Roberto Fonseca added an answer in Simulators:
    How can we simulate the Hodgkin & Huxley model by Matlab code and simulate action potential?

    any details for answering is in the link below.

    Paulo Roberto Fonseca

    Hi, I'm not familiar with this kind of simulation but I've saw two very interesting examples on the internet.

    + 1 more attachment

  • Fangfang Qi added an answer in Dura Mater:
    Anyone familiar with the immunofluorescence staining of MHC-II in dura mater?

    Hi, all. I am staining of MHC-II-postive cells in the dura mater of mouse. I find that the MHC-II-postive cells contain two cell morphology, the rounded and the branched, please see the green cells in the figure of attachment. I think the cells contain lymphocyte and macrophages. But now i would like to distinguish the two types of cells using different immune makers? Anybody can tell me?

    Thank you very much!

    Best regards,

    Fangfang Qi

    Fangfang Qi

    Thank Kritika very much! I not sure whether there are only two APCs in the dura mater. I have double-stained for MHC-II (green) and CD11b (red) (a maker for macrophage), however, only few duble-stained cells were detected, see figure 3. I also stained for CD3e for the T-cells, but not stained for MHC-II because the two antibodies are made in same animal (Rat). Recent a data confirmed that few MHC-II-positive cells express CD3e, see figure1 and 2. Could you send me some researches about CD14 or CD64 staining for Macrophages (immunoflurescence method). Thank you again.

    Fangfang Qi.

    + 2 more attachments

  • Mudassar Nazir asked a question in Acoustic Resonance:
    Is there any guy works on piezoelectric Zno thin film for bulk acoustic resonator?

    I am working on bulk acoustic resonator so i want to deposit Zno as a piezoelectric thin film.

  • Jae Gu Lee asked a question in GWAS:
    How can i use different version(llumina beadchip) of maker position?

    HI, nowdays i use illumina beadchip for GWAS analysis.

    I have 2 type chip. It' s bovinesnp50_v1, bovinesnp50_v2.

    But it has different chromosome, maker position in the SNP_map file.

    So, How can i use different versions.

    Can i imputation from bovinesnp50_v1 to bovinesnp50_v2.

    If I can imputation it. After imputation, how can i use different version of maker position?

    i wanna know answers. Have a nice day : )

  • Daniel Dehany Scott added an answer in Basic Bioinformatics:
    What is the best way to define promoter targets of two (or more) different transcription factors?

    Hi there,

    I'm performing some (very basic) bioinformatic analysis of our gene of interest, part of which is looking at the different transcription factors that may regulate it using the ENCODE Regulation track on the UCSC Genome Browser.

    One particular question I'm interested in asking is: what promoters in human cells bind the same set of transcription factors as my GoI?  In more specific language, which genes in the genome have a strong ChIP signal for two (or more) defined transcription factors within, say, 3kb upstream of their transcriptional start site.

    I'm very new to this kind of whole-genome dataset analysis and as a result am a near-novice; any advice anyone could give on how to do this kind of analysis in a reasonable time would be greatly appreciated! 

    I'm expecting to need to download various genome viewer(s) and or datasets etc., but at largely at sea regarding: a) what best to use for this and b) the method/approach or coding required to e.gh. define the TSS distance and the requirement for double-positive ChIP signals is beyond me. 

    Alternatively, if there is a useful programme/took/database for this  that I am unaware of, please do let me know!

    Thanks in advance for all help!

    Daniel Dehany Scott

    Great, thanks Joseph!  To be clear, I do know which TFs I'm keen to look at - but just wanted to try a couple of different pairwise combinations.

    Just to clarify, is BEDTools a standalone programme or an extension to something like the UCSC Genome Browser?  And is there a particular way of defining the, say, 3kb upstream? Or is this a built-in option to the programme?  Apologies for the many questions - very much a "learning by doing" approach to bioinformatics!



  • Vinod Kumar asked a question in TRNSYS:
    How to design new component using FORTRAN in TRNSYS, kindly mention the step by step procedure please. I've already read the manuals?

    I am struggling to create dll file of my newly designed component in fortran. Kindly send me suitable example please.

  • Vash Patel asked a question in Primer:
    What kinds of selective media can one use to confirm that a culture is, in fact, A. calcoaceticus?

    I have a stock culture that I plan to use for further experimentation, but I first need to ensure that it is, in fact, A. calcoaceticus. I do not have the ability to get any type of sequencing done, other than performing PCR with primers that I can order. What are my options?

  • Tulsi Bhandari asked a question in Social Science:
    Would you suggest good literature to differentiate mediator, moderator and interaction effect in social science research?

    I am getting confusion.

  • Mudassar Nazir asked a question in Acoustic Resonance:
    Please tell me,How piezoelectric Zno thin film works?

    I want to deposit piezoelectric Zno thin film for high overtone bulk acoustic resonator.

  • Vinod Kumar asked a question in TRNSYS:
    How to create new component using FORTRAN in TRNSYS, please mention the step by step procedure

    It is also requested to please send documents/example file if any

  • J Mark Olsen added an answer in Trauma:
    Does anyone have any interesting references on memory distortion and eyewitness evidence?

    How can trauma affect the distortion of a memory? 

    Any studies on brain activity?

    Memory distortion

    Eyewitness evidence 

    J Mark Olsen


    The Neuroscience of Memory: Implications for the Courtroom

    also (can not use directly) buy look to the references: https://en.wikipedia.org/wiki/Eyewitness_testimony

    How does a traumatic event, such as witnessing a crime, cause ...
    www.researchgate.net/ post/ How_does_a_traumatic_e...

    (I'm a doctorate student as well as a law student)

  • Mudassar Nazir added an answer in Microelectromechanical Systems (MEMS):
    Is anybody working on piezoelectric thin films?
    Is anybody working on piezoelectric thin films?
    Mudassar Nazir

    Please tell me about the working of piezoelectric Zno thin film. 

  • Inigo San Millan added an answer in Exercise Therapy:
    What is the effect of intensive exercise on diabetic patients?

    We want to find the  effect of intensive exercise therapy on diabetic patients for reducing their blood glucose levels. Would like to know what kind of measurement tools can be used other than blood glucose readings, HbA1c levels. 

    Inigo San Millan

    In terms of long-term adaptations there is not much conclusive data. A typical characteristic in many people with T1DM is post-exercise hyperglycemia which is one of the top complaints in T1DM and one of top reasons why they don't stick to an exercise program. If high intensity exercise, not rare to see severe hypoglycemias in the middle of night. They take too much insulin to correct post-exercise hyperglycemia and they end up with hypos. 

  • John O'Brien added an answer in Landscape Ecology:
    From a spatial view: What can be considered the "landscape scale" ?

    Something I always asked myself: In the field of Landscape ecology. How do we define and parametrize the "landscape scale" from a spatial view? What counts as a landscape and what is just the minimal covering area of all field sites? Are landscapes intrinsically defined by the social-ecological boundaries of humans that interact within them or is there sth. like a general theorem that defines the spatial scale (per ecological or environmental process) that a landscape can operate on?

    My current view is that landscapes as such seem to be limited (in terms of spatial scale) by the question a researcher intends to address. Some processes (such as dispersal) act on a greater landscape scale including the surrounding, while others require a much finer focus towards the studysites. But this is obviously inherently biased by my (or others) perception as a human and other species might "perceive" a landscape not (only) in terms of processes.

    Appreciate any cool references to seminal or review papers that investigated this.

    John O'Brien

    I think the best approach is to consider what constitutes a landscape for the species or processes under study.  The landscape impacting on an ant is generally going to be reduced compared to a deer for instance.  We need to get away from defining landscapes based on human perceptions, and consider how the species we study perceive them.

  • Ethirajulu Mahalakshmi added an answer in Spondylitis:
    Is cervical traction is effective managaement for cervical spondylitis?

    MRI impression : patient of cervical spondylitis with c5 c6 c7 disc herniation indenting subarachnoid space. Age 40 yrs, Spinal stenosis lumbar region 2years back treated with medicaion and exercise.

    Now my query is about cervical traction can be given to this patient with interferential therapy followed by neck exercises. or only steroid medication effective for this condition.

    Ethirajulu Mahalakshmi

    Hi Vaner Koksal,

    Its 12 mm according to the MRI. 

  • Paul Miller asked a question in Medical Director:
    Should medical directors reconsider how hemodialysis facilities categorize, capture, escalate and analyze HD related hypotensive episodes?

    Would standardizing coding utilizing accessory modifiers that better describe and discriminate dialysis-related hypotensive episodes improve risk prediction models, result in effective escalation and mitigation strategies, strengthen problem-solving approaches, enhance comparative research, and reduce repeat preventable harm to patients?

    Validated research over time may prove that a more stratified hemodialysis hypotension classification will reliably predict impending doom, and effectively crack the code to prevent failure mode.

  • Tulsi Bhandari added an answer in Psychometrics:
    What is minimum required sample size to compute Cronbach's alpha reliability for questionnaires/ scales?
    I am going to develop and validate women's autonomy measurement scale.
    Tulsi Bhandari

    For correlating items, use correlation matrix among items.

    Your second question is not clear, I think, you mean, three levels of rating. Whether three point or five point or more, no matter you can use cronbach's alpha for internal consistency test ...

  • Timothy Bahry asked a question in Citric Acid:
    Why did lemons evolve to be so acidic?

    There's only one possible answer I can think of and I don't know if it's correct. This is one possible answer:

    Lemons at first were slightly more acidic than oranges. Because of that they could corrode teeth faster than oranges. Any animal that corroded a hole in the enamel layer would be less likely to rear as many children and those that ate more lemons were more likely to corrode a hole in the enamel layer so natural selection selected for animals that slightly dislike lemon and prefer to eat oranges if they're available to eat. In addition to that, lemon trees were more likely to reproduce if fewer of their lemons got eaten and the ones with more acidic lemons had more of a tendency for animals to learn their lesson not to take a second lemon and eat it so natural selection selected for trees that produce more acidic lemons. That in turn caused even faster natural selection for animals that dislike lemons, which in turn produced faster natural selection for trees that produce more acidic lemons until it it starts approaching an evolutionary stable strategy where lemons are so acidic that it's so rare for animals to eat them that the biological cost of producing more citric acid is equal to the biological gain of having fewer animals eat their lemons as a result of producing more citric acid.

  • Rubén Daniel Ledesma added an answer in Metabolomics:
    Can I use the factors derived out of principal component analysis for conducting Pearson correlation analysis?


    I have run PCA to reduce my metabolomic data to 5 meaningful factors. I was wondering if I could use Pearson's r to show a linear dependence between one of these factors and C-reactive protein. Does it make any sense?


    Rubén Daniel Ledesma

    Hello Kaido!
    Reducing data via PCA and then make a correlation analysis is a usual data analysis strategy.

    Some statistical software allows you to include "supplementary" variables in the PCA. I guess that it would be usefull in your case ... so I suggest you to explore that option. 



  • Yen Sen Liang added an answer in Method Validation:
    Method development for determine VOC using HSGCMS?

    I been running a method validation using Head space GCMS, but encounter some problem, now is there is high saturation of chromatogram at the start? what else can I improve and have a proper peak?

    Other comment also appreaciate.

    Attached with all the setting and chromatogram

    Yen Sen Liang

    Hi Konrad,

    Before I enter next phase, I encounter some problem and currently asking the GCMS engineer to help me, 

    When I using the sim mode, there is totally no peak come come, I don't know why. But if I use scan mode there will be peak come out, i still waiting for engineer solution for it.

    I think our column and setting is different, that why eluent time is different for benzene.

    Btw are you using the same method for testing? in what sample? Thank for the help to remove the methanol peak, scan from 40 really help to remove methanol peak.

    Best Regard,


  • Matthias Wilhelm added an answer in EMR:
    Streetlights r deliberately manufactured to provide illumination with reddish color.Based on EMR and spectral reflectance relationship suggest why?

    please answer with reference..

    Matthias Wilhelm

    Looks like these lamps are very energy-efficient, check Wikipedia:


  • Narendrakumar Ravi Varadharajulu asked a question in N2a:
    Can anyone suggest me a good co culture model for n2a and glial cell line?

    Im  trying to establish a co culture platform for N2A and glial glial cell line for neurodegenerative disorder study..

    I see some papers have directly cocultured cell lines.. but I need a system where I can control the cells seperately but have them in same environment.

    I would appreciate any suggestions.

    Thank you

  • Darrin Thomas added an answer in AMOS:
    Can we use Structural Equation Modeling (using AMOS), with small data sample (n = 40) ?

    I have a data set of 40 participants, and I want to develop an model using SEM, can we use Structural equation modeling with this small data set (n = 40), if all recommended GoF are satisfactory.

    If you know please answer / reference.

    Darrin Thomas

    The sample size is too small. In addition, there would be difficulty with external validity based on whatever results you find whether using SEM or Smart PLS. Lastly, it is doubtful such results would be publishable. 

  • Roberto Kasuo Miyake added an answer in Vascular Surgery:
    Vascular surgery: What is the energy needed to obliterate a great saphenous vein using EVLT 1470nm? In total J ? and J/cm
    And the energy needed using 980nm laser ?
    Roberto Kasuo Miyake

    I've been using radial fiber since October 2009. More recently, the double ring radial fiber. I use 40 to 50J/cm

  • Yen Sen Liang asked a question in Oil:
    Reference oil used in Oil and Grease in FTIR determination?

    Now I develop the method for Determination of oil and grease by FTIR

    After I search through some reference, I notice the reference oil use in calibration standard is different to each other:

    Method 418.1 Hexadecane, isooctane and chlorobenzene

    EPA 5520C isooctane, hexadecane and benzene

    Hach 10056 Stearic acid and hexadecane

    Do I know any different? i know hexadecane is aliphatic and isooctane is branded and benzene is aromatic, but I don't understand why HACH using only aliphatic alkane for calibration?  Is it any specific reason?

    Hope someone can help me. 

  • Matthias Wilhelm added an answer in Wireshark:
    What are the best opensource tools for packet capturing in network research. The aim is minimize packet losses experienced in wireshark(50%)?

    Different solutions have been employed but packet loss ratio is very high. The best up till now has been wire-shark. Kindly guide as to how we can increase the capture ratio and what software are commonly used in the community for this purpose.

    Thanks in advance for your help.

    Matthias Wilhelm

    Can you give more details on what you are looking for? It sounds like your Wireshark causes packet loss during capture, but I don't think that is likely. The software just puts a network interface in listening mode and receives all packets, even packets that are not addressed to your machine. It is not a computationally expensive task, so I can't think of a reason Wireshark should cause losses. At least other software will have the same problem, they probably also use the standard libpcap to capture the packets.