Q&A

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  • Brenda Jacono added an answer in Sparrows:
    Are agreement or disagreement for the following statements?

    The self-confidence
    - Make from a sparrow to a hawk
    - Make from rose a garden .
    - The dream becomes true.

    Brenda Jacono · Cape Breton University

    Yes I agree with your points. As for the bit dealing with birds, I agree with Bob. I would say to that point that we come as eagles not sparrows, but through life circumstance can tend to become sparrows. Eagles can also end up as big fish not minnows.

  • Colin Zhang added an answer in Spectroscopy:
    Can any researcher help me the testing of electroabsorption(EA) spectroscopy of photocell or only in EA spectroscopy?

    I want to use EA spectroscopy for the measurement of build in potential of metal/oxide/metal structure.

    Colin Zhang · Simon Fraser University

    surface analysis may work

  • Manisha Rao asked a question in Exosome Isolation:
    How to isolate circulating DNA from human serum without lysis buffer?

    I am working with exosomes isolated from human serum.I want to isolate circulating DNA from human serum as well, but without disintegrating the exosomes. This means, I have to avoid using any sort of detergent/lysis agent. Any suggestion is appreciated

  • Pejman Abbasi added an answer in Acinetobacter:
    How can i identify acinetobacter baumannii by biochemical tests?
    I'm going to identify acinetobacter baumannii in my lab.
    Pejman Abbasi · Professor Alborzi Clinical Microbiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.

    TSI: aik/aik, citrat: +, non_ motile, indol -, Danase: - , oxidase: - , lactose non fermentation in MAC media,multi- drug resistance , usually acinetobacter baumannii was sensitive to colistin and polymyxin B.

  • Pir Asmat Ali asked a question in Araneae:
    I required papers on spiders (araneae) of Tobacco plants. ?

    please send me pdf if some one have in his PC or have worked.

  • Farid Alisafaei added an answer in Shape Memory Polymer:
    Can anyone provide the UMAT subroutine with some explanation/tutorial about how to use it in conjunction with ABAQUS?

    Hi, I am working on shape memory polymers and their glass fiber composites. I need to analyze their thermomecahnical behavior in structural application. At the moment I need to use ABAQUS for the analysis which needs the user material define subroutine UMAT. It will be very helpful if any one can provide me with the UMAT and some explanation/tutorial about how to use is in conjunction with ABAQUS.

    Farid Alisafaei · University of Wyoming

    Hello Wessam,

    Attached, please find a tutorial on writing user subroutines in abaqus (including UMAT), in case you have not already found it.

    Below, there is also a link where you can download several UMAT codes (including elasticity, plasticity and visco-plasticity problems). These UMAT codes are all explained in the following book:

    "Introduction to Computational Plasticity" by Fionn Dunne and Nik Petrinic. 

    Link to UMAT code:

    http://www.eng.ox.ac.uk/NP/ICP/

    Best Regards,

    Farid

  • Anthony Simon asked a question in Tigers:
    Is the threat of wrongful trading a paper tiger?

    Is the threat of wrongful trading in the insolvency act a paper tiger?

  • Hamdy Elsaid abd elhamed Elnawasry asked a question in Jamaica:
    Why sprinters of Jamaica the first in Athletics World Championships and the Olympic games?

    I want to know is this superiority due to environmental factors or the type of food or particular training method

  • Courtney G. Collins asked a question in Respiration:
    Could anyone point me to protocols for running substrate induced respiration (SIR) via lab flask incubations on a LICOR-8100A?

    I am trying to get a sense of how long I should run the LICOR after glucose addition to get a good estimate of CO2 flux. These are dry alpine soils with low OM. 

  • Aftab Alam added an answer in HEPES:
    How can I calculate the quatity of HEPES needed for my medium (ATCC DMEM 30-2002)?

    How can I calculate the quatity of HEPES needed for my medium (ATCC DMEM 30-2002)?

    Aftab Alam · National Centre For Cell Science, Pune

    DMEM uses a sodium bicarbonate buffer system (3.7 g/L), and therefore requires a 5–10% CO2 environment to maintain physiological pH.

  • Rodrigo B. Singer added an answer in DNA Barcoding:
    Does anybody have information about plant DNA barcode as tool for identification of illegal traffic of endangered species?

    I am looking for information about plant DNA barcode as tool for identification of illegal traffic of endangered species. Thank you very much in advance.

    Rodrigo B. Singer · Universidade Federal do Rio Grande do Sul

    I think Barbara Gravendeel and her colleagues can help you. Below there is a link to a paper of them. All the best!

    https://www.researchgate.net/publication/278317555_Conservation_of_Endangered_Wild_Harvested_Medicinal_Plants_Use_of_DNA_Barcoding

  • Geetak Gupta added an answer in AlGaN:
    Why don't the electron from the surface donor states recombine with the +ve polarization sheet charge in the AlGaN-side in the interface in AlGaN/GaN?

    We know that most of the 2DEG-electrons in the undoped AlGaN/GaN heterostructure comes from the surface donor states (UK Mishra et. al and Guang et. al.). These electrons are driven by the electric field due to two sheet charge at the AlGaN-surface (-ve) and the interface (+ve). Now, when the electrons from the surface donor states travel to from 2DEG, they have to go past the +ve sheet charge in the interface (AlGaN-side). Why don't the electrons recombine with the +ve sheet charge before getting confined into the GaN side of the heterostructure and forming 2DEG?  

    Geetak Gupta · University of California, Santa Barbara

    Theoretically, spontaneous polarization is a bulk property of the material. So even if have just bulk AlGaN or bulk GaN, there should be polarization. This means that accumulation of electrons and holes should happen at the ends of the crystal. Confinement can happen at the ends as the carriers will be sitting against the vacuum energy level. If you make an ohmic contact at the two ends, it might behave like a p-n junction.

    However, I think these are hypothetical scenarios because it is literally impossible to have surfaces without surface states. Also making ohmic contacts is also a tricky concept and will introduce complications. In the end, both ohmic contacts and surface states can change the properties at the surface. It is therefore extremely difficult, if not impossible, to detect such charge separation in bulk polar materials. Therefore, typically we only discuss polarization at heterojunctions.

  • Gedion Firdawek asked a question in Management Control:
    What are the management control mechanisms for effectively and efficiently managing budgets in an organization?

    What are the management control mechanisms for effectively and efficiently managing budgets in an organization? 

  • Michał Stępień added an answer in Soil Organic Matter:
    Where can I find 'official' standards for organic matter levels in arable soils and in forestry?

    The best would be UK standards.

    Defra and lab gives target levels but I cannot find what they are depending on crop/climate/soil type.

    Thank you!

    Michał Stępień · Warsaw University Of Life Sciences

    Dear Thomas, according to my observations in Poland, for arable soils, 5% of organic matter would indicate excess of water (in other words - insufficient aeration). Some information about percentage od soil with different humus content classes you can see in the paper I attached (about Poland and Baltic Sea), table 2.8, page  74 and 75 (or 76-77 according to the file) you can see, that about 47% of Polish soils have "average" level of organic matter between 1 and 1% of it (0,58-1,16%C). It is interesting to compare Polish and Peruvian critical levels:

    low <1% (Poland), <2% (Peru),

    average 1-2% (Poland), medium 2-4% (Peru)

    high 2-3% (Poland), >4% (Peru)

    very high >3% (only Poland)

    And now, I saw, that there is an error in Peruvian table "alto" (high) should be changed by "bajo" (low) and vice versa :-(. Well errors are common, in some Polish documents also exist... (and not only Polish).

    When considering target values, they should/must be different depending on land use, soil texture and other factors, as it was written in other answers. In sandy soil it is impossible to increase C content significantly even using 100t/ha of farmyard manure (it would be illegal- Nitrate Directive), because in such soil organic-clay complexes cannot be formed and other form of organic matter is easily mineralised.

    Other interesting aspect - in

    Nair P., K., R. 1993. An introduction to agroforestry. 489ss, dostępny pod adresem:
    http://www.worldagroforestry.org/units/library/books/PDFs/32_An_introduction_to_agroforestry.
    pdf?n=161

    in table 14.3 it can be seen, that high organic matter content i so considered a limiting factor. It probably refers to organic soils, but, perhaps also some mineral ones?

  • César Calvo Lobo added an answer in Physical Therapy:
    How do I measure cervical lateral tilt and Axial rotation in spasmodic torticollis patient?

    I am providing physical therapy treatment in addition to Botox injection for a patient with Idiopathic Spasmodic Torticollis. I would like to know any valid method to determine the cervical lateral tilt and axial rotation..

    This patient presents with combination of right cervical lateral tilt with left rotation.

    I find difficult to measure it. since, it is not isolated movement.

    César Calvo Lobo · European University of Madrid

    I attach a very interesting paper in relationship with your question:

    Pang D. Atlantoaxial rotatory fixation. Neurosurgery. 2010 Mar;66(3 Suppl):161-83.

  • Marques Jackson asked a question in Trizol:
    How do I get a greater yield in a RNA isolation of the Hypothalamus?

    I am having trouble getting a better yield for my RNA extraction. I use the Trizol reagent protocol for isolation of RNA in my Rhesus Macaque brains. Some issues I have include not getting a pellet after removal of the aqueous phase, and having to re-centrifuge the supernatant of my sample. I originally practiced the protocol using Cerebellum and would receive an initial yield of about 100 ng/ul, and following the re-centrifugation of the supernatant would usually get a yield anywhere between 750-1000 ng/ul. Now I have moved on to harvesting the Hypothalamus but have received substantially lower yields and I have had to re-centrifuge the supernatant multiple times.

    Does anyone know what a typical yield for RNA in the Hypothalamus should be? Also, any suggestions on how to get a pellet would be greatly appreciated. I have increased the time and RPM's at which I centrifuge and am still not able to get pellet formation.

  • Ayan Mukherjee added an answer in Gas Detection:
    Can anyone give me the theoretical details of the gas sensing property of metal sulphides or oxide thin film?

    I want details of gas sensing details. If anyone can provide  vedio or animation vedio then it will be also great.

    Ayan Mukherjee · University of Burdwan

    I want to know about sensing property of CdS thin film in case of H2S sensing. Why CdS sense a particular gas and why not for others?

  • Miriam Aczel asked a question in Shale Gas:
    What do you think the biggest gaps or issues within the current regulatory framework for shale gas extraction / hydraulic fracturing in the UK are?

    For my MSc thesis, I am conducting an examination of the potential environmental and health risks or impacts of hydraulic fracturing.

    Using the recent U.S. experience as an analogue, I have examined potential risks to human health and the environment, and am analyzing the regulatory frameworks currently in place (in both the U.S. and UK) to manage these risks.

    The goal of this project is to identify gaps in the current UK regulatory framework for shale gas extraction, and to propose a series of policy recommendations with the aim of enhancing environmental and public health protection. 

  • Arno Gorgels added an answer in Event Horizon:
    What do you think about the S. Hawking`s idea of the solution of information paradox?

    "I propose that the information is stored not in the interior of the black hole as one might expect but on its boundary, the event horizon,"

    At Monday's public lecture, he explained this jumbled return of information was like burning an encyclopedia: You wouldn't technically lose any information if you kept all of the ashes in one place, but you'd have a hard time looking up the capital of Minnesota.

    The translations that occur form a sort of hologram of the original particles, Hawking said -- a hologram in the sense that 3-D information is recorded on a 2-D surface. When radiation leaves the black hole, it carries some of that information preserved on the event horizon with it.

    Arno Gorgels · Principia Naturae

    Dear Saeed, it is correct that long before gravitation becomes as strong as to crush the star's body, quanta as a resut of the compression take over and, in fact, gravitation plays no role any longer; in a way, it disappears until such time that the evaporation of the star in standard em-waves as well as em-waves, called background radiation has taken place and new matter appears. BH is in fact a birth process rather than a process of disappearing "all". 

  • Wangsa Tirta Ismaya added an answer in Recombinant Proteins:
    Can anyone suggest a tool to concentrate a recombinant protein after endotoxin purification?
    • Amicons (Millipore) are not endotoxin free
    • I need to concentrate form 1,5 ml to approx. 250 ul
    • It's a HisTag protein
    • The weight of protein is 53kDa
    Wangsa Tirta Ismaya · Dexa Medica

    what if you switch: concentrate the protein first with the amicon filter, then pass the protein concentrate through a endotoxin removal column (e.g. ET clean from asahi kasei).

  • Sunil Biala added an answer in Fish Toxicity:
    Can anybody tell me how to calculate LD10, 50 and 90 for fish toxicity analysis?

    fish toxicity analysis

    Sunil Biala · Khalsa College Amritsar

    I am working on biological treatment of industrial effluents especially effluents from textile and tannery industries. I then check genotoxicity of these in rats and also check on toxicity on fish. looks to be working somewhat on similar lines.....

    Where r u from?

  • Emmanuel Yujuico added an answer in Human Capital:
    Does a Public Human Resource Dataset exists?

    I want to analyze human resource data set to extract common features of human capital have left organization and to predict future turnover. I have a lot of literature texts on job leaving but I can't find any Public Human Resource Data Set for applying in Data Mining Algorithms.

    Can anyone suggest me a solution?

    Emmanuel Yujuico · The London School of Economics and Political Science

    I'm not sure if US data will work for you, but there are very large datasets available from the US Office of Personnel Management website. See the link below.

  • Ibrahim T. Nassar added an answer in HFSS:
    Frequency dependent surface impedance boundary in HFSS?

    Dear all,

    I want to know how to assign a frequency-dependent "impedance boundary" to a surface in HFSS. I know I can use the variable "Freq" , but what I have is tabulated values of the surface impedance Zs stored in a file "Re(Zs) and Im(Zs) vs. freq.", where Zs is the surface impedance calculated elsewhere using more accurate models.

    Ibrahim T. Nassar · ANSYS

    So the problem is resolved?

  • César Calvo Lobo added an answer in Shoulder Arthroplasty:
    How do I improve the motion of the hand behind the back in reverse shoulder arthroplasty?

    Change of humeral retroversion (20 into zero) matters? Subscapularis repair matters? 

    César Calvo Lobo · European University of Madrid

    Dry needling of the subescapularis myofascial trigger points related with surgery can improve the signs and symptoms of the shoulder:

    Greiner SH, Back DA, Herrmann S, Perka C, Asbach P. Degenerative changes of the deltoid muscle have impact on clinical outcome after reversed total shoulder arthroplasty. Arch Orthop Trauma Surg. 2010 Feb;130(2):177-83.

    Wright T, Easley T, Bennett J, Struk A, Conrad B. Shoulder arthroplasty and its effect on strain in the subscapularis muscle. Clin Biomech (Bristol, Avon). 2015 May;30(4):373-6.

    Buckley T, Miller R, Nicandri G, Lewis R, Voloshin I. Analysis of subscapularis integrity and function after lesser tuberosity osteotomy versus subscapularis tenotomy in total shoulder arthroplasty using ultrasound and validated clinical outcome measures. J Shoulder Elbow Surg. 2014 Sep;23(9):1309-17

    Ingber RS. Shoulder impingement in tennis/racquetball players treated with subscapularis myofascial treatments. Arch Phys Med Rehabil. 2000 May;81(5):679-82.

    Shin HJ, Shin JC, Kim WS, Chang WH, Lee SC. Application of ultrasound-guided trigger point injection for myofascial trigger points in the subscapularis and pectoralis muscles to post-mastectomy patients: a pilot study. Yonsei Med J. 2014 May;55(3):792-9.

  • Chandan Joishi asked a question in Traps:
    What are EADs and AHTs?

    What does energy alternating defects and as-grown hole traps signify? Can anyone provide me with supporting materials.

  • Tarun Kanti Sarkar added an answer in Corrosion:
    What are the recent research interest and challenges in Green Inhibitors for corrosion control and protection of Metals and Alloys?

    Substantial research has been done on corrosion inhibition by plant extracts, my interest is in identifying associated challenges which will form the basis of my research focus.

    Tarun Kanti Sarkar · Indian School of Mines

    Green inhibitors are a need of the time. Research on corrosion has been an interesting topic for quite a long time. Recently many works are being done on the field of green corrosion inhibitors. Amino acid and carbohydrate compounds and glucose can be potent  corrosion inhibitors. I am attaching a paper, hoping that you find it useful. 

  • Shankar Subramanian added an answer in Rheumatoid Arthritis:
    What causes plasma to turn to a yoghurt-white color in a heparine tube (green top)?

    We received blood from a patient with rheumatoid arthritis and after centrifuging the sample we realized the plasma was yoghurt white in color. Is this a defected tube? It appeared too white to be due to hypercholesterolemia but perhaps it's possible. 

    Shankar Subramanian · Armed Forces Medical College

    Dear Marc Hilhorst,

    Such a opaque yoghurt like plasma is classically seen in hypertriglyceridemia. I recall a patient of HIV on protease inhibitors who had a milky serum and triglyceride levels of 1930 mg/dl. She responded very well to fenofibrate with TG levels settling to 185 mg/dl. The other causes of such high TG are usually familial syndromes.

    In a setting of rheumatoid arthritis, leflunomide has been known to cause life threatening hypertriglyceridemia and pancreatitis.

    Was this patient on leflunomide?

    regards

  • Rogerio Kwitko-Ribeiro added an answer in Metallurgy:
    What is the best current chemical metallurgy technique of beneficiation for magnetite ore?

    I am working on the beneficiation of magnetite ore and possible metallurgical testworks to reduce the levels of Si, P in the ore. Any new ideas from chemical metallurgy that can help us advance with this project? Grind size alone does not seem to solve the problem

    Rogerio Kwitko-Ribeiro · VALE

    Do you know if the magnetite has exsolutions of ilmenite? This will add a new contaminant to reduce: Ti.

  • Sepehr Rezaeimalek added an answer in Soil Improvement:
    What happens when polymer is added to soil?

    Hello everyone,
    I am currently working on the idea of using polymers on soil to improve the soil's mechanical properties. What I do includes mixing a polymer precursor called Diphenylmethane diisocyanate (MDI) with water and soil and then wait for the mixture to cure and solidify.
    What I know is that MDI and water perform a chemical reaction which makes polyeurea and emits carbon dioxide. The problem is that I do not know much about chemistry and 1- I want to know the exact equation of the reaction (the name and the formula of polyeurea, to be specific) and 2- I want to know whether or not any chemical bonding between the soil aggregates and the polymer happens or not.
    Is there anybody who could help me with this?
    Thank you very much in advance.

    Sepehr Rezaeimalek · University of Texas at San Antonio

    Thank you very much for your response. The challenge here is the variability of polymers and soil. What happens with one polymer and soil, may not be the case for other soil and polymer. I am biased that soil remains intact in terms of chemical activity with polymer, but proof is required for this and I am still thinking for solutions to ascertain a conclusive answer.