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  • Jose Joseph added an answer in Photolithography:
    How do we calculate exposure in photolithography?

    We are using Karl Suss MA6/BA6 and the lamp power shows 350 W and we do exposure for 10 sec. i am confused how to find power per unit area? which area to consider - mask or source area??? kindly help

    Jose Joseph · Indian Institute of Technology Hyderabad

    Lamp power may be 350 W. As you power up your machine, you do a lamp test and see the intensity shown in the display nearby the lamp power display. It will be some mW/cm^2. You can believe this value if your machine intensity is calibrated on a regular basis. This is the source intensity. If you spin coat a photoresist for a particular thickness, find out the dosage required for the same thickness and divide the dosage with the intensity of lamp. You will get the required time of exposure.


  • Jack M Gallup added an answer in RNA:
    Processing PAXgene RNA Blood Tubes?

    We store PAXgene RNA Blood tubes at -20°C short term, defrost at room temperature for 2hours. Process manually using Life Tech MagMax isolation kit.

    Receiving RINs over 7.0 and over 1ug of RNA consistently. So no complaints, mostly just nosy to see what other people do

    How does everyone else process their PAXgene RNA tubes?

    Jack M Gallup · Iowa State University

    Just in case RNases are still active (for unknown reasons) be sure that the 2 hr r.t. thaw is not excessive.  The PAX tubes thaw at ~ 1hr correct?  If so, proceed with activity at ~1 hr, not 2...

  • Humza Bin Masood added an answer in Water Harvest:
    Has anyone investigated the impact of water harvesting programs on micro-climates?

    If more water is retained in a landscape it will affect soil and air temperature, milders peaks and lows and more - and also different soil biological processes. Looking for cases and evidence..

    Humza Bin Masood · Forman Christian College

    Hi Frank,
    Please check this link.

  • Azadeh Amiri added an answer in Abaqus:
    How can I enter the compressive strength, tensile strength in ABAQUS?

    How I can enter the compressive strength, tensile strength in ABAQUS???

  • Guojing Luo asked a question in Adipose:
    A question about the shape of human adipose derived stem cells?

    i am doing research about human adipose derived stem cell. in normal condition, they exhibit elongated, spindle-like shapes. but now they has flattened polygonal morphologies with much slower proliferation ability. who can tell me why? thany you!

  • Jack M Gallup added an answer in Fluorophore:
    Does anyone know about the StepOne rt-pcr instrument?

    I want to use the StepOne instrument to monitor the fluorescence changs isothermally. The fluorophore and quencher are FAM, BHQ1, respectively, However, BHQ1 is not concluded in the options of StepOne software. I wonder how i can standardize the final fuorecence value. 

    And is this feasible? 

    Jack M Gallup · Iowa State University

    Just lie to the machine and tell it that you are using MGB-NFQ and you will be fine... low signal-to-noise ratio is the hallmark of BHQ1 and MGB-NFQ...

  • Kevin A. McLemore added an answer in Gender Analysis:
    Can you identify this scale?

    I need help identifying a scale (see below). A former research assistant of mine incorrectly labeled this scale as Roccas et al.'s (2008) Measure of Identification with Groups. Now, I've used this scale in a couple of studies, but I do not have the correct citation. The scale has been adapted for use with lesbians.

    1. I have a lot in common with other lesbians.

    2. I have strong ties to other lesbians.

    3. I find it difficult to form a bond with other lesbians.

    4. I don't feel a strong sense of being connected to other lesbians. 

    Any help you can offer is greatly appreciated. Thank you. 

    Kevin A. McLemore · University of California, Davis

    That's it! Thanks, Joanne!

  • Azadeh Amiri added an answer in Abaqus:
    Can we capture the non-isotropic properties of concrete in ABAQUS?

    Dear All,

    Now, I'm modeling the concrete structures by ABAQUS. Nomarly, for concrete, we use the isotropic properties, like we just input one stress-strain curve for compressive/or tensile behavior, and they use it for 3-dimensional damage.

    So if we want to simulate the concrete structure with different compressive/or tensile behaviors in two/or three dimensional, how can we capture this properties for concrete model in ABAQUS?

    When I read from manual for CDP model, look like they just apply for the isotropic properties of concrete! I sorry if I have wrong understanding.

    If any one have a ideal, please give me the answer!

  • Tasha Raella asked a question in Mirror Neurons:
    Is it possible for hyperactivity in the mirror neuron system to produce a partial out-of-body experience that only affects the eyes?

    I am a congenitally blind person who has sporadic visual experiences while under the influence of marijuana. When I use my eyes, I feel like they are floating away from my face and landing on different objects, but they remain tethered to my face. I also sometimes liken the sensation of diverging and converging my gaze to bending or straightening a limb. Since the mirror neuron system has been implicated in both supernumerary limbs and out-of-body experiences, I would be curious if it was indeed plausible that the haptic/kinesthetic aspects of my visual perception could be explained by hyperactivity in the mirror neuron system.  My tendency to mirror gestures that I see, and to project images I see onto parts of my own body, also cause me to hypothesize that the mirror neuron  system is hyperactive.

  • Aashiq H Kachroo added an answer in Gene Targeting:
    What database should I use when I want to find some possible target genes of a transcriptional factor?

    What database should I use when I want to find some possible target genes of a transcriptional factor?

    Aashiq H Kachroo · University of Texas at Austin

    Try ENCODE. Here is the link:


  • Joseph Gosnell added an answer in Transplant Immunology:
    What are your thoughts and experience regarding transplanting chronically hypotensive recipients?

    We have had a couple of recipients recently who ran pre-transplant systolic in the range of 60-85. They both had sustained oliguric ATN for 2-3 weeks post-renal transplant, but eventually did OK.

    We made sure they were well filled going into their operation, with no fluid taken off on dialysis on day before surgery. They had both been anuric prior to transplant, making the anaesthetists slightly nervous about intra-operative over-filling. We ran them on heparin infusion post-op because of increased risk of thrombosis. They were nursed on ICU post-op on noradrenaline titrated to MAP of 65 for couple of days, following which MAP dropped to 60.

    Is there a threshold systolic BP below which transplant should not be considered? Is midodrine etc. useful (doesn't seem to be used so much in UK compared to when I worked in US)? Would you run heparin infusion or LMWH because of thrombosis risk? Are post-op pressors for target MAP useful, or does this just vasoconstrict the allograft and prolong ATN?

    Joseph Gosnell · Liberty University

    Based on my experience in Michigan, hypotensive patients do not seem eligible for transplant. One patient went into hepatorenal syndrome who was chronically hypotensive and required octreotide, midodrine, and albumin just to reperfuse the renal tissue. That patient made an amazing comeback from renal failure, but sadly died a few months later after a bout of aspiration pneumonia. 

    In answer to your question, it seems that hospitals in the Michigan area find chronically hypotensive patients less-than-ideal for transplant.

  • Emily Marie Abbott added an answer in Skeletal Muscle Fibers:
    In a freshly dissected skeletal muscle fiber, is it possible to see striations under a light microscope without staining or skinning the fiber?

    We are measuring sarcomere length heterogeneity in different muscle fibers.  I plan to measure the sarcomeres under light microscope and then run the same fiber through gel electrophoretic analysis.  Therefore, I'd like to visualize the striations without using chemistry that may affect the outcome of the gels.  

    I'm new to histology, any help is appreciated, thanks!

    Emily Marie Abbott · University of California, Irvine

     Thanks Cory! Your google-fu is better than mine.  I did play with the contrast and light but I didn't think of polarized light.  Off to ruin somebody's sunglasses...

  • Ahmed Hussein asked a question in Evaporation Rate:
    What is the best formula to estimate the total heat content (change in storage of thermal energy) ?

    I want to estimate the evaporation rate (daily) by using Penman formula, so I need to calculate the change in storage of thermal energy of the lake. I found many formulas in some publications but I don’t know which is the best also they are just formulas (no details). I have data of the water body temperatures at different depths for many floating stations.I good formula but explained in details.


  • Heru - Pramono added an answer in Anaerobic:
    How to make e. coli breathe anaerobically?

    I need e coli to breathe anaerobically in order to test my inhibitor, how do I do that? Please answer ASAP! 

    Heru - Pramono · Airlangga University

    i hope this information can help


  • Ranju Chapagain added an answer in Climate Variability:
    While assessing the climate variability and agricultural inputs on Water footprint of rice, what else can I use beside statistical approach?

    I want to look into climate variability and agricultural inputs on water footprint. Besides, using correlation, path coefficient analysis and the significant test, what else method can I look forward while looking into that aspect?  And while looking into climate variability, should I consider climate change as well.

    Ranju Chapagain · Asian Institute of Technology

    thanq will try to see if i can go that way.

  • John Texter added an answer in Zeta Potential:
    How do I run a zeta potential on a ph range from 2-10 for folic acid?

    I am doing a zeta potential run over a ph range for folic acid alone. I am adjusting the ph with HCl for attaining low ph and NaOH for attaining high ph. But with folic acid showing low solubility in water, attaining a stable system seems difficult. But as i move to a higher ph range and adjust with NaOH the system becomes clear ( as understood with folic acid showing better solubility in NaOH). Any inputs?

    John Texter · Eastern Michigan University

    Titus, I think it is fair to say that we know from micellization of charged surfactants, that dispersion forces typically dominate. Additionally, industrial colloid scientists know that most aqueous colloids tend to be intrinsically negatively charged, and are further stabiiized by adsorbing additional negatively charge surfactant. Charge does not repel alkyl chains, only same-sign charges. See the attached papers for a handful of examples where intrinsically negatively charged colloids adsorb negatively charged surfactant; these examples are only the tip of the "iceburg." Did you mean to say "that surfactant adsorption on polar surfaces of identical charge is negligible or zero"? I categorically disagree with such an assertion, and the adsorption data in the attached papers prove my point. See the paper attached to my first answer above (OMT adsorption onto a monomethineoxonol with intrinsic benzoic acid ionizable surface groups), and the Colloids Surfaces paper attached below with intrinsic ring-opening carboxy groups and three or four different negatively charged surfactants. If in fact you meant charged surfactant adsorption onto surfaces of opposite charge, you have the same hydrophobic driving force for adsorption and some additional electrostatic driving force. Best wishes, John

  • Mohd Sayeed Akhtar added an answer in Flax:
    Can anyone help in getting seeds of linseed/Indian flax?

    Dear friends.... I need your help in getting seeds of the Lin seed/Indian flax (Linum usitatissimum L.) accessions available in india.....or any idea in which institute or research centre they were available....i tried my best from different sources here but didnt get any......??

    Mohd Sayeed Akhtar · Putra University, Malaysia

    Dear Kiran Kumar,

    In my opinion you should contact to IARI, PUSA NEW DELHI, but they will supply the research material only when you may approach through your department.

  • Heru - Pramono asked a question in Pediococcus:
    How to study role of some specific bacterial strain in food matrix?

    I have a Pediococcus that isolated from mud crab gastrointestinal and want to use it as culture starter for new fermented fish product. Due to it isolated from animal and want to apply in food, i want to know how it role and fate in food matrix, any suggestion? 


  • Shamsul Bahari Shamsudin added an answer in Industrial Safety:
    Which one is better in explaining the relationship between the antecedents and safety behaviour: TPB, TAM or UTAUT?

    I want to investigate the readiness of industrial workers toward application of behavioural based safety program in their workplace.

    Shamsul Bahari Shamsudin · Universiti Malaysia Sabah (UMS)

    All three models of behavior (TPB, TAM or UTAUT) has its own advantages and disadvantages. In general, these models have been developed in western countries where there may be some discrepancy as compared to the behavior of critical asia society (role of demographically, belief, culture, etc.). However, we recommend that you refer to or develop the new behavioral model in line with the local community.

  • Joseph Gosnell added an answer in Dissection:
    Could you tell me the best source for learning to dissect the prefrontal cortex of mice?

    I would need a paper or video that it shows me to dissect with accuracy the prefrontal cortex of mice for synaptosomes

    Joseph Gosnell · Liberty University

    Below is a video from the Journal of Visualized Experiments. Hopefully, it will help you.

    It is supposed to be a video on the full prep of mouse brain to isolate synaptosomes. Let me know if it did not fully load. I often have trouble with downloads from JOVE.

  • Tsung-Che Chiang added an answer in Hyper Heuristics:
    Is there any Hyper Heuristic Framework developed for university course timetabling problem? or for educational timetabling problem?

    like other problem domains, is there any Hyper Heuristic Framework developed for university course timetabling problem? or for educational timetabling problem? 

    Also refer recent hyper heuristic methods developed or proposed for university course timetabling problem? 

    Kindly refer link. 

    Tsung-Che Chiang · National Taiwan Normal University

    Hi Rafia,

    As I know, Prof. Rong Qu is an expert in this field. You may want to check her publications at her web page. (https://www.nottingham.ac.uk/computerscience/people/rong.qu)

    The ASAP research group is one of the leading groups in the field of hyper-heuristics. You may also check the their publications. (http://www.asap.cs.nott.ac.uk/?q=bibliography)

    Hope this information is helpful to you.

  • Richard Traub added an answer in Vestibular System:
    Anyone familiar with the Vestibular System as a Leverage Point?

    It seems like the vestibular system is integrated into cognition and emotion, and also that it's not getting that much attention as a potential leverage point for improving cognitive or emotional functioning. Does anyone have resources on either:

    1) Interventions that have successfully improved vestibular function along with any cognitive or emotional issues at the same time. Or,

    2) Vestibular function decreasing as an adaptation to prolonged inactivity or low vestibular stimulation.

    Richard Traub · Understanding Piano Technique

    Hi David,

    I think this researcher's work, which I discovered yesterday in the course of my routine daily surfing for material, ought to help you along quite nicely:


    Best regards!

  • A. Subba Rao added an answer in Soil Quality:
    Is there any single soil parameter which may help describing the soil health/quality?

    Is there any single soil parameter which may help describing the soil health/quality?

    A. Subba Rao · Coromandel International

    As I understand,neither one parameter serves as indicator of soil health ,nor one set of minimum data serves the purpose every where.One has to identify a list possible parameters ,test/evaluate them in a  uniform geographical area/agroecosubregion having some uniformity in soil, cropping  pattern and climate and identify the minimum data set for assessing the soil health in that area.While listing the parameters, the suggestions given by several colleagues need to be kept in view.

  • Paresh N Patel added an answer in Ligand:
    Which technique can be considered as best for Ligand - DNA binding study ?

    ct-DNA, Chalcone based ligands. (How to overcome solubility problem of ligand)

    Paresh N Patel · Indian Institute of Technology Madras

    Dear Marcos,

    Thank you very much for your answer. I want to know about which kind of interaction is there between prepared lidands and DNA. Currently I am trying with UV (its showing decrease in intensity with increasing DNA conc. with fixed ligand conc., but after certain conc. its shows sudden increase) and Fluorescence spectroscopy (its continuously increasing). So I am not able to make any conclusion !!!!!!!!!!!!

    I am a pure chemist, do not have much experience about biological work. I have numbers of ligands, but struggling with bio work.

    We have UV & Fluorescence spectrophotometer, CD, Viscometer, Gel electrophoresis in our lab. I am learning most of the equipment............  

    Also can you please suggest me how to overcome solubility problem of ligand in buffer ??? because some of ligands are not soluble.  

    Once again thank you very much for your answer ............


  • Heru - Pramono added an answer in Antifungal Activity:
    Is there a simple method to screen bacteria for antibacterial or antifungal activity ?

    I am looking for simple methods to screen bacteria  for antimicrobial or antifungal activity in 80  isolates against  standard lab bacteria strains (Micrococcus, Serratia, E.coli, Staphylococcus) or standard lab fungal strains (4).

    Heru - Pramono · Airlangga University

    we use agar disc diffusion method for doing screening. last month we conducted screening about 100 isolates with this method and done satisfied enough

  • Joseph Gosnell added an answer in Fatty Acids:
    How to isolate long chain fatty acid producing bacteria?

    Hi, i want to ask, which kind of bacteria belong to long chain fatty acid producing bacteria? and how to isolate long chain fatty acid producing bacteria? Thanks!

    Joseph Gosnell · Liberty University

    A few Bacillus species produce long chain fatty acids (B. subtilis and B. megaterium). 

    In order to isolate them, here is the general procedure:


    Here are some test results for B. subtilis:


    And results for B. megaterium: 


    Hope this helps. If not, please let me know and I will more than happily continue looking for alternative bacteria or tests.

  • Mohd Sayeed Akhtar added an answer in Magnaporthe:
    How to prepare the spore suspension of Magnaporthe oryzae?

    Instead of the spore spread all over, I see lumps while using the haemocytometer for spore counting. 

    Mohd Sayeed Akhtar · Putra University, Malaysia

    I agree with Oadi view, To prepare the spore suspension of Magnaporthe oryzae, first of all you should add Tween 20 to the spore suspension, after that shaking for 5-10 min depends on the concentration of spores. Still you may see the lumps then go for its dilution before counting the spore.

  • Jenny Ng added an answer in Applied Kinesiology:
    How do I quantify weekly physical activity?

    When examining subjects at baseline, prior to an experiment, air displacement plethysmography is performed in order to determine anthropometric dimensions. A part of this involves asking the subjects to rate their weekly physical activity. The options given are: 

    "Very active", "Active", "Low Active", and "Sedentary". The question is, how would one quantify what "very active" is, versus "active". I usually ask how many hours a week do you engage in physical activity, in which you sweat? Is there any standardized scale that quantifies these categories, or any reference that would explain these terms in detail. 

    Thank you 

    Jenny Ng · Grantham Hospital

    IPAQ is a good suggestion.  It consists of activities of various levels, walking and sitting time. Weekly exercise time can be calculated and estimation of MET-minutes per week is available.  

  • Luiz Almeida asked a question in Coding:
    Is it possible to create a UML-based information-theoretic dynamical model for protein biosynthesis?

    Unified Modeling Language™ (UML®) Resource Page - http://www.uml.org/

    Is there an error correcting code in the base sequence in DNA?
    Liebovitch, L.S. et al., Biophysical Journal , Volume 71 , Issue 3 , 1539 - 1544


    Various Coding Based Frameworks Suitable for Error control in Genetic Sequence Analysis, Bhawani Sankar Biswal, Anjali Mohapatra, Conference: IEEE Workshop on Computational Intelligence: Theories, Applications and Future Directions, July 2013, IIT Kanpur, India


    Error Correction Coding: Mathematical Methods and Algorithms 1st Edition by Todd K. Moon 

    Portal:Molecular and cellular biology - https://en.wikipedia.org/wiki/Portal:Molecular_and_cellular_biology


  • Elwira Kaminska asked a question in Dendritic Cells:
    Can monocyte derived DCs produce M-CSF or GM-CSF?

    Hi there,

    MCSF can be produced by variety of cells and I was wondering if anyone know whether M-CSF (and GM-CSF) can be produced by monocyte derived dendritic cells?