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  • Jiawei Liu asked a question in Communication:
    PhD applicant looking for research groups to work with?

    Hi, I am applying for the admission of an electrical engineering PhD program of 2016 Fall semester. My areas of interest include millimeter wave communication, propagation modeling and relative signal processing algorithms in the communication area. Could anyone recommend any currently active research groups in the areas I mentioned?  P.s. Groups in the U.S would be preferred.



  • Jobrun Nandong added an answer in Control Systems Engineering:
    What is the best software to draw control block diagram?
    I'm writing my thesis and I am searching for good software to draw control block diagrams!

    Any suggestion?

    Thank you!
    Jobrun Nandong · Curtin University Sarawak

    You can simply use MS power point as most control block diagrams are not as complicated as plant drawings. If the control diagram has more components or blocks with a lot of signals in-out, use MS visio will do. Most important thing is to have good scientific contributions and drawings are only secondary - sufficient that they are visually clear.

  • Susantha Jayasundara added an answer in Forest Biotechnology:
    How much water is needed to produce 1 m3 wood?

    What are the water consumption during the production of different types wood species like popler, eucalyptus, oak and pine etc in different bio-geographical regions like tropical, subtropical and temperate. I just want to know what are the consumption of water in cubic meter for producing the one cubic meter of wood of above mentioned species in different places ?

    Susantha Jayasundara · University of Guelph

    Hi Anil,

    You can refer to the Table 6 in the following paper (available in the link below) for the Water footprint of harvested wood from different trees and different places of origin.  Here is a short summary of the values from the Table 6 of this paper:

    Pine (Temperate and Boreal biomes) = 335 – 1000 m3 water/m3 wood

    Broad-leaves (e.g. Oak and Poplar) (Temperate biome) = 262 – 797 m3 water/m3 wood

    Eucalyptus (Tropical and Sub-Tropical biomes) = 222 – 1105 m3 water/m3 wood


  • Thein Than Thwin asked a question in Malware:
    May I know some disadvantages of dynamic malwae analysis?

    I want to know some disadvantages of dynamic malware analysis.

  • Chistine Rose Roberts added an answer in Conflict Studies:
    What is the legal requirements for the international community to be involved in the bombing of Syria?

    When the US led forces bombed IS in Iraq it was a formal invitation of the Iraq government in a bid to stop IS. However  the situation is Syria poses a different scenario. The Syrian government has not endorsed the bombing of IS, there is no UNSC mandate and the US/Aus is not under direct threat of attack. 

    The bombing appears to be against the International Law of War. Given the above under what legal justification does the US/Aus have to bomb Syrian towns often killing citizens.

    Chistine Rose Roberts · Deakin University

    Yes I agree. Just a side issue then does the attacks against Syria by the US and allies amount to state terrorism? 

  • Trung Luong Cong added an answer in Tilapia:
    What is a suitable tank size for tilapia of 5gm?

    I am designing a vaccination trial for tilapia (red tilapia) of mean weight 5 gm per fish . I need to use 20 fish per tank . can you help me to choose the best tank size and best water volume to get good results with avoiding the hierarchy and aggressive behaviour of tilapia ?

    Trung Luong Cong · Nha Trang University

    For flow through system, the tank size could be 40x30x30 (cm), water volume could be 30L and water depth is 25 (cm).

  • Burhan Ullah added an answer in X-ray Diffraction:
    How we can find the the angle of tilt of the Octahedra form atomic co-ordinates?

    Can any body know, how we can find the angle of tilt of the octahedra from the atomic co-ordinates? 

    How we can know about the short and long range cation/vacancy ordering from XRD spectrum? How we can know that these short  and long range cation/vacancy ordering indicate tetragonal  or orthorhombic  distribution? 

    Burhan Ullah · Huazhong University of Science and Technology

    Thanks Respected Artur Braun , for your valuable suggestion. Can you send me some related documents(papers) related to to the above mention topic.

    ---------------Thanks once again.................... 

  • Mari Galiher added an answer in Creativity:
    Farman talks about creative misuse. Share an example of creative misuse that you experienced or may have seen before?

    Farman, J. (2012)

    Mari Galiher · University of Hawaiʻi at Mānoa

    One that has recently been talked about much in the news is Ashley Madison. The site was controversial in itself, which could be interpreted as creative misuse of a technology/website. The second interpretation of misuse is that of those hackers who used technology and software to hack the site and reveal information of users, because Ashley Madison did not comply with hackers in shutting down the site. I feel both can be viewed and interpreted as creative misuse of technologies that could have been used for the "better" 

  • Feliciano Chanana Paquissi added an answer in Coronary Artery Disease:
    Can plasma C-reactive protein (CRP) be used as a screening tool to select among low-risk patients to stratify Coronary Artery Disese (CAD)?

    The high cost of diagnostic methods, even of biochemical markers, limit many of the tools necessary for the diagnosis of CAD, especially if we consider the group of low-risk patients. Can CRP be a cost-effective strategy, as some studies have shown, to stratify these low-risk patient groups and separate which should effectively continue the investigation to elucidate the presence of CAD?

    Feliciano Chanana Paquissi · Clínica Girassol

    From current evidence, there is no additional benefit of using CRP for low-risk population. The findings of two recent studies suggest no benefit:

    1. Kuoppamäki M, Salminen M, Vahlberg T, Irjala K, Kivelä S-L, Räihä I. High sensitive C-reactive protein (hsCRP), cardiovascular events and mortality in the aged: A prospective 9-year follow-up study. Archives of Gerontology and Geriatrics; 2015 Jan;60(1):112–7. 
    2. Ho JS, Cannaday JJ, Barlow CE, Reinhardt DB, Wade WA, Ellis JR. Usefulness of High-Sensitivity C-Reactive Protein Versus Coronary Artery Calcium for the Detection of Obstructive Stenoses in Stable Patients. The American Journal of Cardiology; 2013;111(3):328–32. 

    A previous meta-analysis concluded that adding CRP improved prediction and risk stratification from intermediate-risk persons.

    1. Buckley DI, Fu R, Freeman M, Rogers K, Helfand M. C-Reactive Protein as a Risk Factor for Coronary Heart Disease: A Systematic Review and Meta-analyses for the U.S. Preventive Services Task Force. Ann Intern Med; 2009;151(7):483. 
  • Suleiman Ham added an answer in Electron Beam Deposition:
    How can I increase adhesion of Al film on polymer surface?

    Now, I am trying to deposit pure Al film onto PMMA(acrylic) surface by e-beam system. however,I found out that it had poor adhesion between pure Al and PMMA.

    Dose anyone/expert can provide any information or suggestion relating to how to increase the adhesion between pure Al and PMMA for me. Example, what cleaning process, buffer layer or anything I can use it. Thank you for help in advance.

    Suleiman Ham · National University of Malaysia

    After cleaning the substrate ,use Ar Plasma with low power and long period before deposition.

  • Yawar Abbas added an answer in Memristor:
    Does anybody have any reference about the shape of the boundary between the two resistive zones in the HP memristor?

    In the majority of models, the boundary between the resistive zones in the memristor is just a vertical line, i'm looking for references where this interface has another shape.

    Yawar Abbas · Myongji University

    you can refer to my paper  http://www.ingentaconnect.com/content/asp/jnn/2015/00000015/00000010/art00028

    which is going to publish on 1st October

  • Pradip Kumar Kamat asked a question in Gene Transfer:
    Can anybody share a protocol of viral mediated gene transfer method?

    Can anybody share a protocol of viral mediated especially AAV mediated gene transfer method and the most relevant protocol to get prominent results?

  • Yawar Abbas added an answer in DC Sputtering:
    What is the minimum thickness one should deposit using DC sputtering to have a continuous layer? Is it possible to deposit 1 nm of continuous layer?

    What is the minimum thickness one should deposit using DC sputtering to have a continuous layer? Is it possible to deposit 1 nm of continuous metallic layer? Is there a way to check if the layer is continuous or not apart from doing TEM on the samples?

    Yawar Abbas · Myongji University

    I think it is not possible to deposit 1 nm layer

  • Alexey Pankine added an answer in Cygwin:
    Has anyone tried to compile Mars Climate Database (MCD5) on Windows under Cygwin?

    I'm getting compilation errors that look like this: "call_mcd.o:call_mcd.f:(.text+0xb544): undefined reference to `nf_inq_varid_'

    Alexey Pankine · The Space Science Institute

    Nope. Apparently the problem is in linking the NetCDF libraries.

  • Anne C Martinsen asked a question in Catholicism:
    Does anyone know of recent case studies on Catholic/Anglican leadership?

    Specifically on the analysis of leadership styles and the relationship to congregational growth? 

  • Ravi Kumar asked a question in Dispersion:
    How to study the dispersion of solid in liquid using measuring jar?

    how to study the dispersion of solid in liquid using measuring jar?

  • Yawar Abbas added an answer in Thin Film Deposition:
    How can I deposit micro and nano (100nm--) particles on a surface?

    How can I deposit micro and nano (100nm--) particles on a surface, just like the dust on the surface? 

    Yawar Abbas · Myongji University

    If your nanoparticles are in colloidal or solution form then the best way is dip coating.

  • Nizar Matar added an answer in Boating:
    Is immigration to Europe deserved risking the lives to sinking or to stay in the countries that are burning and destroying in wars?

    Thousands of people (children, women, youth) were dead after ships and boats crowded with illegal migrants sank in the Mediterranean. The media and authorities described grisly scenes of bodies floating and submerging in the waters.
    About 400000 illegal migrants reach Europe during 2015.

    - Is the living in Europe worth so that the person risks the live of his family members?
    - Can Europe absorb such large numbers of immigrants?
    - How to solve the immigration problem?

    Nizar Matar · An-Najah National University

    It is not a case of being attracted to Europe. The immigrants are escaping from extremely horrible & miserable conditions at home. Immense atrocities target them at home to kill them & demolish their houses. The least possibility is to arrest them on factional grounds to subject them to tortures & show them hell on this earth. They risk their lives because they are going to lose them sooner or later at home. The most reasonable solution is to stop all the persecutions & violations of human rights at home & to get rid of all the gangs that have terrorized these humans including the authorities' gangs (they do not deserve to be called armies). Before that, it is vital to expose those who fuel troubles in these countries to keep dominating them forever.   

  • Amir Zamri asked a question in Disorders of Sex Development:
    Any advice on ethical issues related to disorders of sex development? Any readings to suggest?

    Philosophy, bioethics, psychology

  • Judy Slome Cohain added an answer in Evidence Based Practice:
    Can anybody recommend good books on evidence based practice, requesting to suggest books to those who are beginners in exploring EBP?

    evidence based medicine

    Judy Slome Cohain · All the way home birth service

    Examples of Decision Based Evidence making;

    Cesarean for breech birth metaanalysis by Hannah M

    induction for Postdates  by Cohain JS  (JObGYNRepMed 21050

    I can send you more- in other words, in Medicine, there is great bias in the way experiments are set up- to get the 'Evidence" they want

  • K. V Sharma added an answer in Solar:
    Can someone tell me how the Vacuum Wavelength/Frequency of sunlight can be related with weather fluctuations of a particular day?

    Hello all 

    I am modelling solar dish collector in COMSOL. I want to redo my model for various weather conditions i.e., Hot sunny, cloudy, cold sunny days with and without clouds. 

    Apparently I can vary the Vacuum wavelength or frequency under ray properties. Can anyone please tell me some empirical values for such different weather conditions and also for different parts of day. 

    Default value of COMSOL is 660 nm and 4.54e14 Hz.

    Any help in this regard will be highly appreciated.

    Thanks a lot

    K. V Sharma · Universiti Teknologi PETRONAS

    As you are working with a software, you can vary the wavelength in a wide range and determine its impact on your analysis.   It might not be necessary to distinguish between the weather conditions.

  • Deo Singh added an answer in GPI-Linked Proteins:
    How to detect GPI-linked cell surface proteins on lymphocytes by Western blot?

    What kind of lysis buffer would be recommended to maximize the solubility of GPI-linked proteins, in order to get good bands by Immunoblot (Western)?


    Deo Singh · Johns Hopkins University

    I know that if you treat the cells with PI-PLC, the GPI-linked proteins will be cleaved off from the cell surface. Please look at PI-PLC protocol. They describe how to collect GPI-linked cell surface protein. 

  • Ashish Kumar Dwivedi added an answer in Model Transformation:
    For the model transformation process, which transformation language can be used?

    For the model transformation process in MDA which transformation language can be used?

    Ashish Kumar Dwivedi · National Institute of Technology Rourkela

    ATL plugin I have checked, ETL and Acceleo I will try.

    Thank you for providing these links.

  • Tausif Alam added an answer in OGTT:
    What test do you recommend for screening of undiagnosed diabetes in a rural setting?

    I was reading the ADA guidelines, which say that HbA1c diagnoses fewer cases of undiagnosed diabetes than fasting plasma glucose (FPG), which in turn diagnoses less cases than oral glucose tolerance test (OGTT). Shall we go for all three FPG, HbA1c and OGTT in the first go? What would you do if you do not want to leave any patient of diabetes undiagnosed?

    Tausif Alam · University of Wisconsin–Madison

    If you have sufficient funds, personnel, and all the needed resources, have them come to your facility (or mobile unit) and do all three tests.

    But first you have to carefully select the criteria for inclusion/exclusion. Random is seldom random enough by all possible criteria.

  • A. Subba Rao added an answer in Fertilizers:
    Which substances would you detect if irrigated UREA fertilizer causes plant damage and yield loss?

    I read already a lot that UREA may cause damage to plant and soil in emerging Asian agriculture. But how can we identify that high fertilized (irrigated) UREA or other N-fertilizers are the causing reasons. We know that metabolized compounds like toxic nitrite NO2 or complex N-carbamate occure for short time and might be some reasons. But what causes and how we can identify the intrinsic factor for plant damage and yield loss?

    UREA may lower pH. But reported soil analysis is:


    phosphorus: 5-20 ppm

    potassium: 70-180 ppm

    humus: 1.2%.

    What can indicate soil EC, even soil is high fertilized (irrigated) with UREA?

    Many thanks for your incoming experiences here.


    A. Subba Rao · Coromandel International

    Thank you Dr. Hani for the attached interesting references .Among the possible causes of seedling  toxicity due to urea application,biuret, ammonium/ammonia and nitrite ,the excess ammonium in plant cells and the nitrite derived from   ammonium appears to be the cause of the ill affects of urea or any ammonium containing fertilizer, when ammonium accumulation is more than nitrification in soil.When ammoniuum ions get converted into nitrate quickly ,possibly the bad affect may not manifest. However it  is often heard from farmers that the proximity of high concentration  of urea to seed may cause the toxicity to seedlings.So in effect ,the excess ammonium in soil during germination may be the causitive factor for seedling injury.

  • Ria Fajarwati Kastian asked a question in In Vivo Electroporation:
    Is anyone has experience in vivo electroporation in brain mice with hippocampus targeted?

    Im trying to do in vivo electroporation (EGFP injection) in P0 brain mice which targeted into hippocampus. After 5 days, GFP positive cells are look localise in hippocampus. But, I wondering about the kind of cell. Because its looks like blood cells with big network inside the hippocampus. 

  • Kelly Hsieh added an answer in Protein Purification:
    How can I optimise protein purification (protein with his-tag) (using complete his tag purification resin by ROCHE)?

    I'm purifying a protein with his-tag (N terminal 6xHis) by using cOmplete his tag purification resin (ROCHE). I've tried several conditions but I can't seem to find the best way to purify the protein.

    I know that part of the problem is that the resin I'm using now elutes the protein during 25-40mM Imidazole, but I still hope to find a way to optimise the purification.

    This is how I'm purifying the protein now:

    1. lyse the bacteria with buffer containing 15mM imidazole (pH8)

    2. incubate the lysate(160mL) with cOmplete his tag purification resin(4~6mL) for 2 hours

    3. load the resin+lysate into column

    4. wash with the same buffer

    5. wash with buffer containing 30mM imidazole (pH8)

    6. elute with buffer containing 250mM imidazole (pH8)

    The final result of the purification will be around 80%. (through SDS-PAGE, and the impurities bands are mainly at the bottom, around 10-17 kDa ) 

    I tried using 25mM imidazole during the lyse process, however the protein just came right off when I tried to wash it for the first time. 

    I also tried using 40mM imidazole during the second wash process, but the loss of the protein was a bit too much. 

    So how can I optimise it? (without changing the resin I'm using now...)

    And... because the impurities bands are mainly at the bottom... I was wondering... could it be that I let the bacteria induction process be too long so that some of the protein broke into little pieces and "happened to" have the his-tag as well?

    Kelly Hsieh · National Taiwan University

    Dear James Carrillo,

    I'm doing my induction process at 37 C right now. If my protein is being broken down inside the bacteria... I should just go with 25 C or even 16 C? I takes me 8 hours to reach OD600=0.6-0.7 and according to the protocol in our lab, the induction process was O/N. I know that normally they say that you should only do the induction for 2-4 hours... so should I retest the kinetics of the induction? or is lowering the induction temperature first is ok? Thanks so much!

  • Khoirotin Nisak asked a question in Phosphates:
    Which one is better for IHC NBF from paraformaldehye or formalin 37%?

    i want to do IHC staining on pancreatic mice, from the previous discussion i've read so many answer but i still not sure which one is better for fixation using paraformaldehyde powder 4%diluted in phosphate buffer pH 6.8 or using liquid formalin 37% in phosphate buffer pH 6.8? and the other one is fixation time, some expert says 24-48 hours but other say there is no problem for fixation time even for IHC staining, thank you for your answer

  • Kevin Lee asked a question in Trizol:
    Keep losing RNA doing Trizol RNA Extractions and Precipitations. Why dont i see pellet sometimes and other times i do?

    Iv been having a lot of trouble recently losing RNA during my Trizol RNA Extractions and subsequent precipitations (with Sodium Acetate and Ethanol).

    In every group, there's always a few samples where the yield is a fraction of the rest of the samples.

    I know it's not the cells themselves or lysis.  So most likely its during the aspirations. 

    The biggest issue is that sometimes ill see a white pellet and other times i wont see anything. Sometimes as in, between trials, but im not changing anything in my protocol so its mind boggling. And just in general aspirating/sucking out the 70% ethanol, I must be sucking out RNA.

    I go from the opposite side of the tube as to where the RNA should be. I tilt the tube first to suck out most of it before i bring the pipetor/aspirator closer to the bottom to get the rest of the ethanol out, but since i cant see the pellet, its hard to get the rest of the ethanol out without risking sucking out the pellet.

    Does anyone know what determines whether you see a white pellet or not? I know if you overdry itll turn transparent/translucent, but im talking when the RNA is still in 70% ethanol. 

    I keep losing samples and its driving me nuts.

  • Amit Nahor added an answer in Polypyrrole:
    Does anybody have a convenient method for removing polymer films from ITO after electrodeposition?

    Specifically polypyrrole or polythiophene films.

    Amit Nahor · Hebrew University of Jerusalem

    ITO can be etched away using different kind of acids as HCl, HF, HBr. 
    From my experience polythiophene is not harmed from HF. You should check about the others acids and for polypyrrole. 
    By etching away the ITO layer the polymer will lift off into the solution. you should be aware that if the polymer layer is too thin it will be hard to keep it intact and it might disintegrate due to the forces in the solution.