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  • Mari Galiher asked a question in Social Media:
    What literature have you read on dis-inhibition in the online context?

    Disinhibition, social media networks, online 

  • Henning Seismann added an answer in Insect Cell Line:
    What difference, if any, are there between the glycosylation pathways of Hi5 and Sf9 cells?

    I know insect cell protein glycosylation is different from mammalian cells but are there differences between different insect cell lines? I am interested in expressing a viral envelope glycoprotein.

    Henning Seismann

    Dear Jeffrey,

    have a look at the following paper whish discribes differences in alpha1,3 core fucosylation between Hi5 and Sf9 (Dissecting cross-reactivity in hymenoptera venom allergy by circumvention of alpha-1,3-core fucosylation; PMID 19896717). 

    As not only allergic people exhibit Ig responses to alpha-1,3-core fucosylation one would expect a clear difference in neutralisation in case of your viral envelope (if applied to humans). Don´t know about mice, but think it´s more or less the same.

    This article might also help: Insect cells as hosts for the expression of recombinant glycoproteins; PMID 10612411

    Kind regards,


  • Lesly Gomez asked a question in Methanol:
    HPLC technical question: What chemicals can I alternatively use to validate my system?

    My manual recommends using caffeine/methanol for UV-VIS linearity, Naphthalene/methanol for carryover check and acridine hydrochloride and anthracene for analysis reproducibility with ACN/H2O. What alternative chemicals can I use especially for the reproducibility? I don't like buying the mixes from the manufacturer because they last exactly 6 months and the chemicals are cheaper by themselves in mg- gram sizes. 

  • Kiran K Andra added an answer in Protein Electrophoresis:
    What is the recipe for SDS-PAGE equilibration buffer?

    I have found two different recipe for equilibration buffer online , and I'm confused which to used and what is the main difference? 

    1st is from the Biorad IPG Strip Manual from this link 


    at page 19

    2nd is from this link


    at page 6

    The main difference is the molarity of Tris HCl, in which the first recipe state that the final concentration is 0.375 M and the second recipe state is 50mM

    Another is DTT in which  the first state is 2% while second is 100mg in 10ml which converts to 1%. Does this make any difference?


    Kiran K Andra

    Check the below links, 


  • Hela Weslati asked a question in Transfection:
    How to transfect primary murine NK cells?

    Does anybody have experience with the transfection of primary murine NK cells? I would like to take my mRNA experiments to a new level and verify my findings, but as far as I read it is not so easy to transfect them. Since this is an important part of my Master project I would be very thankful for any advice.

  • Giorgio Giardina added an answer in Crystallization:
    What is the affect of pH on crystallization process ?

    I am thinking to change the pH of the super saturated solution, will that help growing any crystals? ( in general ) 

    and if so , will it affect my complex??


    Giorgio Giardina

    HI Farah,

    what are you trying to crystallize? Small molecules or macromolecules (proteins, DNA act)? pH is in general one of the many parameters that you should try to optimize, for the obviuos reason that it protonation or deprotonation of functional groups will affect the ability of the molecules to pack or not in a certain space group. But please be more precise if you what more useful answers.


  • Sameer Karpe asked a question in Ammonium Chloride:
    What is the exact role of NH4Cl (ammonium chloride) in aqueous barbier type reactions?

    what is the exact role of NH4Cl (ammonium chloride) in aqueous barbier type reactions?

  • Ngozi ADELEYE added an answer in Income Inequality:
    Where can I obtain detailed Gini indices for African countries (1980 - 2014)?

    Dear colleagues,

    I'm on a doctoral program with a research focus on income inequality in Africa. I will appreciate links to obtaining detailed Gini index for African countries from 1980 to 2014. I've accessed World Bank's WDI and AfDB data sites with not much help there as many countries have lots of 'holes' with respect to this variable.

    Kindly assist....thanks!


    Ngozi ADELEYE

    It sure helps....thanks a lot, Mario!!!

  • Kemal Gökkaya added an answer in Hyperspectral Remote Sensing:
    What is hyperspectral CASI imager and what is its specification ?

     Concerning hyperspectral remote sensing. What is hyperspectral CASI imager and what is its specification ?

    Kemal Gökkaya

    Compact Airborne Spectrographic Imager (CASI) is an airborne hyperpectral sensor originally developed at York University in Canada. It samples in the visible and near infrared portions of the spectrum. The one I used had 72 bands, 4m spatial resolution and 10nm spectral resolution. Please check out the ITRES website (http://www.itres.com/) for information on the most current version, ITRES 1500.

  • Mari Galiher added an answer in Self Disclosure:
    How have you seen individuals self-disclose on Facebook, Twitter, or YouTube?

    I'm interested in research on: individuals with mental illness, self-disclosure, social media networks.  

    Mari Galiher

    Mahalo nui loa (thank you very much in Hawaiian), Dr. Alhaddad and Rozalia, for your feedback! 

  • Leonel São-Romão-Preto asked a question in Basic Life Support:
    Anyone know surveys for assessing knowledge of basic life support in university students (or general population)?

    Anyone know surveys for assessing knowledge of basic life support in university students (or general population)?

    To evaluate the level of knowledge and training needs

  • Viktor Y Butnev added an answer in Cell Aggregation:
    What are some suggestions on completely detaching adherent cells from multi-well plates?

    I am having problems completely detaching adherent cells from 24-well plates. Cell aggregates are especially prevalent around the edges of the wells. I have tried trypsin and TrypLE to detach, and still see many cells attached following treatment.

    Viktor Y Butnev

    If your next step is the cell lysis I would recommend to use 0.2 M NaOH to collect all the cells debries from the wells. If you need to keep the cells intact you probably need to use just cell scraper.

  • José Luis García Vigil added an answer in Computer-Assisted Diagnosis:
    Any solutions for aided pathologic diagnosis?

    I'm going to develop a software to do computer-aided pathologic diagnosis in medical field. But I'm not sure if there is any exsisting good solutions for this. Does anyone know about this? Please tell me or give me some references. Thanks a lot in advance!

    José Luis García Vigil

    Dear Morgan Lei

    I am a physician and clinical researcher and have experience in the automation of educational assessment tools research and development of information systems. I'm not very knowledgeable expert even if the theoretical and practical bases of artificial intelligence and microcomputer programs using advanced programming languages ​​for this purpose (C, C ++, Fortran).

    As a physician, I know in general methods and techniques for anatomical macroscopic pathologic diagnosis with direct visualization of normal organs (apparently healthy) and distinguish diseased tissues and organs (study of organs and tissues, necropsy). Comparing the healthy versus sick what can be achieved with standard technology (photography, video, by comparing images). Basically to analyze qualitative information such work, it is sufficient to use some qualitative statistics and quantitative, which is favored by the use of pre-programmed (STATA, EPI-INFO; EPISTAT; SPSS; XLSAT) statistical packages

    Situation is different when the diagnosis by simple microscopy, phase contrast microscopy and immunofluorescence use. Here the common procedure for diagnosis is the training and special training specialist pathology (anatomical pathologist, clinical pathologist, electron microscopist etc.). Training and skills that enable it to distinguish in the microscopic images, the normal from the abnormal and the healthy from the sick, comparing, and issuing naming specific diagnosis according to whether clinical or medical problem in question.

    In this case, as an aid in the pathological diagnosis assisted by computer, you can use the programming language "artificial intelligence", as described above (C, C ++, Fortran), a tool that allows the use of a catalog of standard images, catalog abnormal images and catalog pathological diagnoses by type of image. These catalogs (databases, fields) are related, they are compared and information that will eventually be the pathologic diagnosis is issued. Of course in software development is required to compare all the issued diagnosis processing that information for diagnosis expert pathologist, all with the purpose of assessing the validity and reliability of the software developed.

    Finally, you could use the new tool called MATLAB, which has many similar to the advantages of the programming language of "artificial intelligence" as previously described applications, but with the advantage of faster processing of quantitative and qualitative data (numbers , categories, number of data, images). Besides the advantage of graphical modeling and managing advanced 2D and 3D.

    Greetings and success in your business


    Dr. Jose Luis Garcia Vigil

  • Thomas Heise added an answer in Autism:
    Autism: what can be done to improve the academic interchange between the justice system and the mental health sector?

    One of the area’s where multi-disciplinary collaboration is direly needed is around the encounter between autism and the justice system. Study on all levels seems warranted. Criminologists should know more about risk-factors in the minds and lives of people on the spectrum, while ‘the autism community’, including parents, schools, care-givers, need to know their way in the justice system. Police often lack understanding of autistic behavior, not infrequently with dramatic consequences. Here and there their local initiatives are taken to educate police-officers (e.g. http://spiritofautism.org/autism-and-the-criminal-justice-system/), but there should be much more. Do police academy curricula include this? I fear not enough. Certainly more people are incarcerated than are recognized as autistic.

    Huge gains are to be expected in terms of the well-being of these patients and their relatives, the crime rate and the related expenditures. I wonder what is already being done.    

    Thomas Heise

    Caroline, my Statement was more in General about the Problems between Justice and psychaitric Problems, while you filled it very lifely with meanings about autism. I really appreciated your description!

  • Gennady Semenovich Melnikov added an answer in Quaternions:
    What is the faithful (and full) representation of quaternions in the three dimensional real Euclidean space?

    I have found a (maybe the) faithful and full representation
    of quaternions in the ordinary real three dimensional Euclidean space.

    A non constant quaternion is the roto-dilation, usually associated
    to it, endowed with a verse ("clockwise" or "counter-clockwise")
    for the underlying rotation.

    A negative constant  -c  is the dilation associated to the positive
    constant  c  endowed with the rotation of  2π  of the space, independent
    of the axis and of the verse of the rotation.

    A positive constant  c  is simply the the dilation having ratio  c, 
    endowed, if you like, with the identity rotation.

    I'm asking if this simple faithful and full interpretation
    of quaternions, in the usual real three dimentional Euclidean space,
    is new or if it is well known.

    Gennady Semenovich Melnikov

    Reality quaternion descriptions proven in studies of physical ( optical ) properties of the formation of the real and imaginary images of optical glass ball.

    Gennady S. Melnikov Space-time fractal unity 


    Оf the physical examination was the author  shows alarms equation geometric field of spatial frequency that is phase supplement symbol K. Maxwell's equations of electrodynamics

  • Chithan C Kandaswami added an answer in Dietary Supplements:
    Is threre research on alpha galactosidase enzyme supplementation for young children and infants?

    supplementation impact

    enzyme activity


    daily intake

    Chithan C Kandaswami

    Here is a link to a study on α-galactosidase treatment of children.

    Efficacy and tolerability of α-galactosidase in treating gas-related symptoms in children: a randomized, double-blind, placebo controlled trial.  BMC Gastroenterology 2013, 13:142  doi:10.1186/1471-230X-13-142


  • Hormoz Sohrabi added an answer in Normal Distribution:
    Does anyone know how to execute an analysis of residuals in score variables (SPSS) to know if variables are normally distributed?

    I want to explore regression assumptions for my variables of interest (in SPSS). 
    I have already made a Kolmogorov analysis, but I'm interested to know the residuals (errors) in scores variables.

    How can I analyze such data?

    I want to do a moderation analysis, but Kolmogorov analysis showed me that my moderator variable is not normally distributed, also the dependent variable and predictor variable. I have a sample of 200 subjects.

    Thanks for all!

    Hormoz Sohrabi

    Dear Sara

    When you have the linear regression dialog box, you can see a button on the right side of the box named "save". Click on it and in the residuals menu select the appropriate one. Usually for normality test i check mark "unstandarded residuals". After clicking final ok, one variable will be added to your data sheet. Now you can select this variable for normality test.

  • Soufiene Assidi added an answer in Meta-Analysis:
    Can someone share some useful materials that provide recent progress about the meta-analysis?

    Can someone share some useful materials that provide recent progress about the meta-analysis?

    Soufiene Assidi

    Dear professor Heng, 

    Possible to see the corporate social responsibility  by Meta analysis 

    best regards,


  • J. W. Zartha added an answer:
    Is there a good online tool for doing Delphi-type polling?
    I need to organize a Delphi polling process for a group of collaborators who are spread out geographically, making physical meetings/discussion on an ongoing basis impractical. Is there a good online tool to help manage such a process?
    J. W. Zartha

    I suggest you check these links:




  • Kevin J. Miller asked a question in Anisotropic:
    Does anyone know of a free (preferably parallelized) anisotropic diffusion filter for edge-preserving smoothing in 3-D grayscale datasets?

    I want to smooth X-ray tomography data to reduce noise but preserve edges as much as possible. I know of proprietary software that does this, but I need freeware. My volumes are quite large (sometimes as large as 1000x1000x1000 voxels^3) so parallelized or GPU-enabled software is preferred. 

  • Kiran K Andra added an answer in Ovalbumin:
    How can I purify reduced protein to get rid of the reducing agent?

    Hi everyone,

    We try to reduce our proteins (Ovalbumin and BSA) with an excess of TCEP. I need the thiols of the protein for further modification.
    Before i can quantify the concentration of thiols (therefore we use DTNB) I need to remove the reducing agent because it also reacts with DTNB.
    Now we tried to perform a dialysis against TE buffer (50mM; 1mM EDTA; pH8) but we loose our reactive thiols?
    Is there any alternative method to purify the protein without loosing the reactive thiols?

    Thank you

    Kiran K Andra

    You can use desalting columns (PD-10) to remove TCEP. which is quick and efficient.  I removed reducing agent using desalting column and labelled protein with fluorescent dye. How much excess do you use ?? If it is too much just use amicon filter to exchange the buffer.

  • Mutasem Odeh asked a question in PDMS:
    Can I deposit ITO (Indium tin Oxide) on cured PDMS using E-Beam evaporator and anneal it after that? to what annealing temperature does PDMS hold ?

    I am trying to deposit ITO on PDMS, will i be facing a problem in adhesion or annealing or any other problems ?

  • Hela Weslati added an answer in microRNA:
    How to transfect primary murine NK cells?
    Does anybody have experience with the transfection of primary murine NK cells? I would like to take my miRNA experiments to a new level and verify my findings, but as far as I read it is not so easy to transfect them. I would have an Amaxa Nucleofector available but I am not sure whether the human NK cell kit would work. Since this is an important part of my PhD project I would be very thankful for any advice.
    Hela Weslati

    Hey Lisa! I konw it has been some time since you have posted this question. However, could you please let me know which protocol for the transfection actually worked out well? I need this for my master thesis! Thanks a lot :-)

  • Maqsood Ali Mughal asked a question in Indium:
    Is indium sulfide an indirect bandgap material or direct bandgap material? or both?

    The bandgap reported for indium sulfide whether it is direct or indirect is still controversial. Anybody shed some light upon it?

  • Sarah Croessmann added an answer in p53:
    Any suggestions on P53 mutation in breast cancer?

    Hello. Many papers show that T47D human breast cancer cells have mutated p53. So, is it possible that there are some T47D cells which have wild type p53 or all the T47D cells existing have mutated p53 and this is kind of a characteristic of these cells? Thanks for the comments.

    Sarah Croessmann

    According to Broad's CCLE, T-47Ds have a L194F mutation.  Therefore, it is assumed that this is a genetic characteristic and all T-47Ds should have the mutated p53.  There are extremely rare situations in which genomic instability could lead to the genetic change of this mutation but it is extremely unlike.  TP53 is mutated in a high percentage of Breast Cancers (approx 25-30%) so it is  common for established breast cancer cell lines to have a mutation.  If you are looking for a cell line with TP53 WT, I would suggest using the CCLE for your search.

  • Michael P. Weinstein added an answer in Global Sustainability:
    Will there ever be effective international agreements to tackle the climate change challenge?

    We are well aware that the complexity of the earth system and increasingly global social and economic systems severely limit the prospects for controllability of the earth system at the global scale. I am wondering whether individual sustainability does/can “add up” to global sustainability.

    Michael P. Weinstein


    As usual, good comments, but I focus on the following from your narrative:

    "Perhaps, if the scientists could get over to the public and their masters via the media how serious the problem is we might have some hope."

    This IS happening, at least at the regional level, but we'll see if a critical mass can be formed to make a difference, long term.  I hope so.  Regards,


  • Manuel Morales added an answer in Foundations of Quantum Mechanics:
    How do we understand a conservation law (Noether's theorem) in quantum mechanics?

    In the classical mechanics Noether's theorem says that

    "if a system has a continuous symmetry property, then there are corresponding quantities whose values are conserved in time"

    As a simple particular case, a quantity A that doesn't depend on time explicitly, neither through other parameters on which it depends, i.e. dA/dt = 0, is a constant of motion.

    The question is what becomes of this law in quantum mechanics (QM)? Does it hold at all? And if it does, what is its meaning?

    The QM gives the following formula for the time derivative of an operator Ȃ:

    (1) dȂ/dt = ∂Ȃ/∂t + i/ħ (ĤȂ - ȂĤ),

    where Ĥ is the Hamiltonian of the system, and Ȃ is a Hermitic operator attached to an observable of the system.

    Assume now that Ȃ doesn't depend explicitly on time and commutes with Ĥ, therefore dȂ/dt = 0. How shall we understand this result? Does it mean that the value of the operator Ȃ is fixed during the system evolution, even if we don't measure it?

    Or, alternatively, does it mean that performing a measurement of Ȃ on identically prepared systems, we are bound to find the same value of Ȃ?

    In other words, in the QM, a quantity which is a constant of motion, possesses a value, and it is fixed in time, independently on whether we measure it or not? Or, alternatively, it takes a value only if we measure it, and the value is the same if we repeat the measurement on identically prepared systems?

    Manuel Morales

    The discovery of Einstein's nonlocal hidden variables means that QM is not a fundamental theory. Which means energy is not conserved. It is created. To confirm this as fact, I have invited grade school children to "Search For First Cause".

    Although my invite to "Search For First Cause" are initially focused towards grade school children, graduates, and post-graduates, I invite my colleagues here at RG to feel free to participate as well (see links).

    As a Nobel Laureate told me in regards to inviting the public to help science correct itself... see "Flawed Scientific Method".

    + 1 more attachment

  • Jaime Bonilla-Barbosa added an answer in Aquatic Plant:
    Can any one help me to identify this aquatic plant ?

    I have collected this plant in an fresh water aquatic pond

    + 4 more attachments

    Jaime Bonilla-Barbosa

    Is Ceratopteris thalictroides (L.) Brongn.