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  • Astro Karthik added an answer in Cancer Cell Line:
    What is the permissible IC 50 value of metal oxide nano-particles/composites against MCF 7 breast cancer cell line?

    Prepared nanoparticles/composites treated with specific cancer lines and we have found half maximal inhibitory concentration.

    How will you say bio compatible material using half maximal inhibitory concentration value?

    Astro Karthik

    Thank you so much scientist raj kumar..

  • Ruchi Jaggi added an answer in Gender Roles:
    Is there any difference between gender role ideology and gender role orientation?

    I read some papers and found that they have same conceptual content.  I wonder if there is any difference. Why did people use the two different terms?  

    Ruchi Jaggi

    Gender is a fluid construct. While most scholars agree that sex as a term has a biological basis, gender is a term associated with social behaviour. That a person's sex should drive their gender orientation and gender role is the most conflictual premise of gender and sexuality struggles. This particular argument has constructed the perception of the term 'gender' over time. Gender ideology, therefore, is the perception of the idea of gender as a fixed or fluid construct. 

    Gender role orientation stems from the concept of gender ideology. Ideas, beliefs and perceptions on gender role ideology may play a significant part in expecting gender role behaviours and an expected gender orientation. 

    Hence, in my understanding, gender role ideology is the framework in which gender role orientation is perceived, experienced and also performed. 

  • Shahid Bashir added an answer in Foreign Language Learning:
    How can we avoid Negative Transfer (Interference) and Pragmatic Failure In Foreign Language Learning (FLL )context?

    First Language Interference and Pragmatic Failure

    Shahid Bashir

    Thank you, Dalal Elge.

    Could you help me to understand your perspective?

    it directs attention to solutions to overcome differences 

  • Aritra Misra added an answer in RNAse:
    Any advice on why am I not able to detect input protein (47kDa) of a ChIP experiment in Western Blot?

    I am doing ChIP of a transcription factor (47kDa) in differentiated hES cells. For the experiment I am using Millipore ChIP kit. We have earlier seen by western blot and immunostaining that upon 36 hrs of differentiation of hES we get homogeneous expression of the protein. But when I am doing the ChIP, I am not able to detect the protein in INPUT sample.
    My ChIP protocol is as follows:

    1. cells fixed with 1% formaldehyde / 10min.

    2. quenched with 0.125M glycine / 10min.

    3. cells collected - washed 3X with PBS (2000RPM / 5min / 4*C) - Flash freeze @ -80*C.

    4. cells lysed in 300ul lysis buffer (SDS lysis buffer + PIC + PMSF + RNAse) - 30min on ice.

    5. sonicated for 20 cycles (30sec on/30sec off) / invert mix and spin after every 5 cycles.

    6. lysed cells + beads + PIC + PMSF + ChIP Dilution Buffer (final volume: 2ml) - pre clearing / 4-6 hrs / 4*C / rotospin: 20RPM.

    7. after pre clearing, beads are pelleted and the supernatant is collected.

    8. 100 ul of supernatant is kept aside as INPUT sample and the rest is taken ahead for ChIP.

    The antibodies used is custom generated and is shown both by immunostaining and western blot to be specific for the protein.

    The lysis and sonication conditions were standardized to give a sheered DNA smear between 500-100 bp with maximum intensity at 300bp.

    the RNase, PIC, PMSF conditions are standardized to get high purity of DNA. (checked by PCI purification of sonicated DNA: 260/280: ~1.84).

    With all these conditions, I am not able to detect the protein (47kDa) in western in INPUT Sample (attaching the INPUT western for the recent trial experiment done)
    The one thing which i think might be causing a problem at the conditions in which i am running the transfer. (120V, 3.00A, 100min, 4*C). And every time I run a transfer I have seen the transfer buffer heating up.
    Do you think this transfer condition is not good for health or there might be something else that i should check.
    By the way, I am using the regular Tris-Glycine transfer buffer.

    Aritra Misra

    Thanks a lot Daniel.

    Ok this was extremely stupid of me that i didn't think about the "crosslinking" problem...
    it is pretty obvious that since my sample is Crosslinked, i am not going to get bands at the expected range.
    But i was thinking that if the problem is "crosslinking", then what if after i take the input, "reverse crosslink" it without using "proteinase K" and then then run the sample in western.
    How about that?
    that will theoretically rule out the problem.

  • Sarbani Ashe asked a question in GC-MS Analysis:
    What is the basic principle for choosing solvents for GCMS analysis?

    Do the samples used for GC-MS analysis vary according to the compounds to be analysed? What if one is not sure of the compounds formed?

  • Mahmoud Ahmad added an answer in Laser:
    I want to mode lock a laser with SESAM and examine every set up but I didn't get any pulsed laser. Is there any thing that I didn't consider?

    F saturation SESAM=70 micro j/cm2

    and modulation depth:.6%

    Mahmoud Ahmad

    I forget remind you to modulate your pump source at frequency range of MHz

  • Ganagavalli Karuppasamy asked a question in Permissiveness:
    My name is included in a publication without my permission. What do I do now?

    A Anwar, A Bhartiya

  • Ayesha Mariam added an answer in Optoelectronics:
    How Exciton binding energy is realated to optoelectronic applications?

    Hello everyone,

    I want to know about that how the Exciton binding energy is important for selecting the material for opto-electronic applications.


    Abhinav Nag

    Ayesha Mariam

    The  distance of separation between electron and hole in semiconductor is Bohr radius. Nano device electronic fabrications are mainly depends upon the its dimensions which should be less than the Bohr exciton radius. Exciton radius is related with its exciton energy which is important to fabricate optoelectronic devices.

  • Lamin B Ceesay asked a question in Financial Services:
    Fellows. Can anyone guide me on a research- how brand associations impact switching intentions on clients of financial services?

    I need some guide here, on the aspects of brand associations to be chosen and methodology, to measure the impact on switching intentions.

  • Jo Barfield added an answer in PFGE:
    Does anyone know what's wrong with my PFGE?

    I‘m a newcomer to PFGE. The marker is H9812. The strains are E coli. As you can see from the picture, there is a band on the top which is brighter than others in every single path, I don't understand why is this the case. Does anyone have an experience about this?

    thank you!


    + 2 more attachments

    Jo Barfield

    hi, can I please clarify with you Richard. Do you mean undigested DNA by the RE or unreleased or unavailable DNA lysed from the bacterial cells (by lysozyme for example).

  • Amipara Manilal D added an answer in Antenna Engineering:
    Can anyone help with Elevation Radiation Pattern?

    Base station antenna coverage area is assured by azimuthl wide beam (Parallel plane with earth).

    I would like to know the utility of the narrow beam il the elevation plane for sectorial antenna? (May be to choose the channel ?)   

    Amipara Manilal D

    Modulation process is carried out, mainly (Unless it is spacial modulation) at circuit level on a electrical signal before it is converted into wave. Modulated electrical signal is converted into wave when radiated. Thus obviously, it is on both the field

  • Kanchan Maji asked a question in Protein Structure:
    Is their any to measure the protein structure of 3D scaffold using Circular dichromism(CD)??

    I have prepared gelatin-chitosan-TCP 3D porous scaffold.I want to check the Gelatin protein alfa-helix and beta-sheet orientation using CD. How am i supposed to prepare my sample for this experiment?? 

  • Tabasum Sidiq added an answer in Splenocytes:
    Can anybody suggest me the MOI for TB which we should use to check the induction of MHC class I in mice splenocytes and macrophages ?

    I have to check the induction of MHC class I expression in the TB infected mice macrophages and splenocytes under in vitro conditions. Can anybody suggest me the range of MOIs for TB which we should use to infect these cells to check the class I induction. I went through some literature and found the different MOIs used by people (mostly MOI 1, 20, 40 and like that). What is the best MOI to be chosen for this experiment? Any suggestion about the incubation time too?

    Tabasum Sidiq


  • Johneph Sukham added an answer in Silicon Photonics:
    Are any of you designing integrated silicon-photonics components? What simulation tools are best?
    Is an electrically based simulation tool (spectre-like) suitable for simulation of optical components?
    Johneph Sukham

    @Philippe Velha What would you suggest for a beginner ?

  • Jo Barfield added an answer in PFGE:
    Why is there no separation in PFGE?

    I tried to use PFGE system CHEF II (Bio-Rad), but even on length marker (also Bio-Rad) I cannot receive any DNA separation. I used 0,5X TBE buffer, certified molecular biology agarose from Bio-Rad, marker samples were... submerge in agarose (on comb) and run conditions were taken from "marker best condition". Natheless I did not obtain any separation, after bromidium ethidium treated almost all DNAs from marker were still in holes. Only one, gentle, fuzzy stripe was visible 1cm under samples. Does anyone have any suggestions?

    Jo Barfield

    We have had a similar problem in the past. It seemed to resolve when we increased the amount of lysostaphin relative to the cell suspension and increased the incubation time to overnight! Now we are getting smearing, which I suspect is being caused by a DNAse contaminant or endonuclease.

  • Ebenezer R.H.P. Isaac added an answer in Applied Artificial Intelligence:
    Could the texts data be labeled automatically instead of label it manually?

    To clarify the question, I did label each example "text" manually, spent a lot of time to prepare data to train it in the classifier. My label was numerical for each example as 1,2 or 3 represent three classes. I read each example and insert the label at first column.

    Is there a possible way to label the dataset automatically, and based on what criteria, while ensuring the performance and bias to each class? Well, the reason is to save time. 

    Ebenezer R.H.P. Isaac

    Sultan, think about the rationale behind your problem; you train a classifier with a labelled data set so that it can label unseen samples automatically, right. Then how could you expect this labelling to be done before the training? That is the whole aspect of supervised classification. If you expect the labelling to be done automatically with some method, then that method is actually predicting the possible class label. Then how could you ascertain whether the labelling is done correctly?

    This ought to be sought out during the data collection process. If you are synthesizing the data set, then this process would be easier. I usually do data synthesis in batches of single classes. That is, generate samples for class 1 then group label as 1, then for class 2 and so on. I would finally randomize the data set for training, cross validation and testing.

  • Harshad Kamble asked a question in Magnetic Field:
    How to calculate force between Permanent magnet and electromagnet?

    I need to calculate force between Permanent magnet (NdFeb) and electromagnet for different voltages(5-24). They are 5 mm apart in the device.

    Currently I had measure the Magnetic field  for Permanent magnet in terms of Magnetic Fled Vs Distance  (197 mT at 5 mm) and for electromagnet in terms on Magnetic Field Vs Voltage (134 mT for 12V at contact). 

    Any suggestions will be highly appreciated.

    Thanks in advance.

  • Oliver Manuel added an answer in Scientific Method:
    Is the modern approach to cosmology fundamentally flawed?

    With the substantial amount of anomalies, paradoxes and unexplained phenomenon in mainstream cosmology, one must question whether the modern approach in this field is sufficient. In most fields of science, development proceeds according to the scientific method: A phenomenon is observed, a hypothesis is made, scientific test(s) are conducted and the simplest answer is sought after. However, this does not appear to be the path that modern cosmology is following (as demonstrated by the attached figure).

    Subjects such as naturalness and fine-tuning have been highly debated in the areas of quantum field theory and cosmology. The argument is that if a theory must be fine-tuned, then there should be an underlying physical reason for such values. However, the vast majority of fine-tuned theories lack explanation and only seem to exist for the purpose of reproducing reality in terms of ad-hoc mathematical formulations. Thus my question is really three parts.

    • Do you believe the modern approach to cosmology is fundamentally flawed?
    • Is a fine-tuned theory that is fundamentally wrong, but can still produce correct predictions useful?
    • Was Richard Feynman correct when he stated “Science is the belief in the ignorance of experts”?

    Examples in cosmology:

    • Redshift versus Luminosity Distance: Requires accelerated expansion via dark energy
    • The Faint Blue Galaxy Problem: Requires disappearing galaxies
    • Dark Matter Cusp Problem: Requires unnatural arrangements of dark matter in galaxies
    • Local Galaxy Counts: Requires a local "hole" that extends beyond 0.05z
    • Horizon Problem: Inflation theorized
    • Size of Distant Objects: Unexplained or significant evolution
    • Planck Sigma_8 Problem: Hypothetical sterile neutrinos proposed
    • Hemispherical Power Asymmetry: ?
    • Directional Dependence of Cosmological Constants: ?
    • The Dark Flow: Theorized interaction with another universe
    • CMB Cold Spots: Massive voids proposed
    Oliver Manuel

    Thanks, Hans, for your comment.

    Precise rest mass data of the 3,000 different types of atoms (See above "Cradle of the Nuclides" ) is a good place to start rebuilding the foundations of physics.  Also may I ask you to help harvest a peaceful and unanimous conclusion to the Paris Climate Conference that will benefit all of society?


  • Syed Abbas Jafar added an answer in Acritarchs:
    I saw some of these bugs in my paly slides but could not figure out what they are. Please could anyone help to tell if they re acritarch or Dinocysts?

    Please would anyone help to tell what these figures listed below are. i saw them in my paly slides but could not say if they are acritarch or Dinocysts?

    + 7 more attachments

    Syed Abbas Jafar

    Hi Celestine:

    Please furnish more details about the material (Age of sediments marine or non-marine) from which you prepared your palynological slides and other associated palynofossils. At this stage it is difficult to say anything about the Acritarch or dinoflagellate nature of the forms you documented (pl. provide magnification).



  • Sunny Igbinere asked a question in Zeta Potential:
    I need a mathematical relationship between pH and zeta potential?

    i need a mathematical relationship between pH and zeta potential?

  • Indra Purnama asked a question in Memory:
    How to determine I/O bandwidth?

    Hello all,

    Can someone briefly explain how to calculate the I/O bandwidth of a memory device?

    If I can move between each bit in 100 m/s, while the width of the bit itself is 1 um, does that make by I/O bandwidth 100 Mb/s?

    100 Mb/s = 100 m/s divided by 1 um

  • Sonal Mazumder asked a question in Encapsulation:
    What is the mechanism of encapsulating microbes to form nanoparticles?

    Often nanoencapsulation is used to encapsulate the microbes for nanobiotechnology based applications. Microbes are in micron range, how can the capsule be in nanometer range to encapsulate them? Does the bacteria shrink or any other mechanism to make them nano?

  • Cecilia Mercado added an answer in eLearning:
    What are the barriers to effective use of elearning by academic staff and students?

    My focus is on Engineering Education. 

    Cecilia Mercado

    technology access can be one barrier

  • Atrayee Baruah added an answer in CMC:
    What is the Critical micelle concentration of sodium oleate?

    What is the CMC of sodium oleate?

    Atrayee Baruah

    Thanks for the information. 

  • Jo Barfield asked a question in Lysostaphin:
    Problem with PFGE - Why is my DNA smearing?

    I am attempting to work up a PFGE protocol for a Gram Positive cocci that is of interest to our lab. However, I am still getting a lot of undigested material stuck up in the loading well. I originally assumed that the SmaI digest was incomplete but we discovered it was the concentration of Lysostaphin relative to the cell suspension. Once we increased the Lysostaphin, we started to see faint bands however now all we are getting is smearing! (see attached) plus a lot of DNA still stuck in the loading well. Does rough handling of the cell suspension or delay in embedding the cells in agarose cause smearing? Or is there something wrong with the electrophoresis tank temperature or buffer temperature and the DNA is degrading? Or buffer, tubing, tank contaminants? Thanks in advance. 

  • Mayur Sailor added an answer in PSAT:
    How can i get a data sheet for IEEE 24 Bus test system with per unit values ?

    I need to perform Power flow on IEEE 24 Bus system using PSAT Tool in MATLAB. And for that i need proper data sheet of IEEE 24 BUS test system.

    Mayur Sailor

    thank you so much Tapan Prakash for your answer &  attachment.

  • Amir mohammad beigi asked a question in Hybrid Vehicles:
    How do hybrid vehicles?

    How to calculate the fuel consumption in electric and hybrid vehicles(phev)?

  • Mayur Sailor added an answer in PSAT:
    How can I get MVA Ratings of the Generators connected in IEEE 24 Bus test system ?

    Basically, according to IEEE 24 RTS data available i have MWs rating available for the Generators connected in that system. But, as i am working in PSAT Tool in Matlab , i need to enter the values of MVA & kV ratings of Generators connected at several buses. Check the attachment figure.

    Mayur Sailor

    thank you so much Bhavans Shah for your answer. 

  • Udaya Kumar added an answer in Carbon Nanotube Synthesis:
    Why do Ni, FE, Co, Cr act as a catalyst during growth of CNT using CVD method?

    Why metals such as Ni, Fe, Co, Cr acts as a catalyst during growth of CNT using CVD method? What is the mechanism behind the growth of CNT over these catalyst? Is there any possibility to use any other more efficient catalyst for better and easy growth?

    Udaya Kumar

    @Per Arvid Löthman: Thank you very much sir. It will be very helpful if you can give me some source of publications supporting these concepts. It will be helpful for me in understanding the concepts in more detailed manner.

  • Shahid Bashir asked a question in Knowledge Transfer:
    Students perspective :Mid-term Exam = copy - paste Final Exam = Cut - paste . Where is the knowledge transfer ?

    Exam-oriented approach is a major threat to knowledge transfer and critical thinking?  It  stifles  students' imagination, creativity, and sense of self.What do you think?