Q&A

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  • Axel Hugelmann added an answer in Photovoltaics:
    Are there hidden and yet untouched forms of energy in photovoltaics?

    It is widely agreed that the average energetic input from solar irradiation on the planetary surface is 1000 W/m² and that a PV panel, depending on it's efficiency ratio, transforms a part of this electro-magnetic energy into electric energy. The question is what happens to the difference between the harvested and the transformed energy?

    A part of it is transformed into heat energy obviously, but is this effect strong enough to explain the difference or could there otherwise be "hidden“ and "yet untouched“ forms of energy?

    Axel Hugelmann · Wirtschaftsuniversität Wien

    Dr. Prof. Zekry, Dear Chittesh,

    thank you for your supportive words. So far I can only say that we charged from PV panels and thermo-electric generators without current. It is now up to us to fully understand the underlaying processes and energy transformations.

    If anybody has input for me especially in the area of ionic charging of rechargeable batteries I'd be glad to read.

  • Barbara Goodrich added an answer in Qualia:
    What role has anticipation in consciousness?

    Philosophers says the brain is an anticipation machine. I miss this statement in the present discussions of consciousness on RG. Is there any interrelation of consciousness, Qualia and anticipation?

    Barbara Goodrich · University of Colorado

    Thanks for the replies!  Louis, if you are not already familiar with Michael Thaut, you might find him useful, too.  His 2005 Rhythm, Music, and the Brain explores his use of music to help Parkinson's patients recover more initiative in motility.  It sounds as though you are working with Steven Mithen and Ellen Dissanayake.  I was thrilled to find these while writing an article (due out in January) on the perception of time and anticipation in music.  (My punchline is that aesthetic experiences of apparent timelessness ironically reveal how much consciousness relies on memory, anticipation, motility-based "purposiveness," and their interactions through time.) 

    I like that your approach would subvert further the old atomistic notion of personal identity, since objects and even organisms could be functioning as parts of more than one nervous system simultaneously.  Not only does this seem plausible in systems terms, but, amusingly, it's how musicians subjectively experience playing or singing together.  And I do think that humans can get some limited sense of a non-human's experience by synchronizing breathing and pulse rates, though this sense isn't quantifiable or always reproducible.  I'm assuming this occurs via subconscious inferences as to what would make one's own biological oscillations take those patterns, though perhaps there is a different connection.  In any case, it may explain how pleasantly hypnotic we find purring cats.    Am I understanding this right?  

    Again, thanks for your time, you all.

  • Raouf Guirguis added an answer in Virus:
    Is there any antibody against high risk Human papilloma virus HPV which crossreacts with other high risk HPV types?

    I need to find an antibody to detect high risk HPV types in one go using western blot. could you kindly let me know if there is any company can provide this antibody?

    Raouf Guirguis · Georgetown University

    Dear Nadia, you can try Santa Cruz Biotechnology, Inc. they offer a broad range of HPV antibodies. You can hen select HPV antibodies from several monoclonal and/or polyclonal HPV antibodies.  View detailed HPV antibody specifications by linking to the specific product blocks. Select appropriate HPV antibodies for your research by isotype, epitope, applications and species reactivity. HPV gene silencer products in siRNA, shRNA Plasmid, shRNA Lentiviral Particle and CRISPR/Cas9 Knockout Plasmid formats are also available.  Here is their website address: www.scbt.com/table-hpv.html

    Regards,

    Dr. Guirguis

  • Contract company to do a small animal study?
    Do any of you know whether you can get a research animal facility to perform a small study on rats (edit: not mice)? I really would like to do an ulcerative colitis rat model that are divided into 4 groups with 8-10 animals per group. These groups are bound to receive a compound that inhibits T-cells. This should be done compared to placebo and standard mesalazine. The compound have been used before and are without adverse effects.

    I would really love if it was possible to pay a research facility (company) to perform the study and after a 2-4 week study the animals / large intestine could be shipped to our lab for further qPCR analysis.

    Is this possible? If possible, then a Europe based company.
    Simona Marie Asinovski · New York University

    Dear Dr. Hansen, 

    I'm from Science Exchange, and we have 63 research animal facilities, than can perform a wide variety of experiments, including CRISPR, Xenograft studies and Animal Behavior Analysis. 

    https://www.scienceexchange.com/browse?category=animal-model

    Let me know if that helps, we'd be happy to help you find the best lab. 

  • Jahangir Abdi added an answer in Stromal Cells:
    Is there a human bone marrow stroma cell line for B cell development from CD34+ cells?

    I am trying to study B cell maturation in vitro, and have found some (older) literature which shows people have done this by putting CD34+ cells from cord blood onto human bone marrow stromal cells (Comparative studies of different stromal cell microenvironments in support of human B-cell development).

    However, I would like to have a cell line instead of having to buy and isolate bone marrow stromal cells. Does anyone know of a HUMAN cell line that supports B cell development?

    Jahangir Abdi · University Health Network

    Yes!, that's right. If  your plan were on mice models the life would be much easier, good luck with your endeavor anyways!

  • David Wells added an answer in FDM:
    What size of bone scaffolds is appropriate?

    There are some articles that has reported the fabrication of bone scaffold via fused deposition modeling. Also the total size of the scaffold in these articles is about 5*5*5 millimeter. I don,t have any information about the positions that scaffold is implanted and also the size of these positions.

    Does anyone know about the sizes that are appropriate?

    Actually I can't fabricate a scaffold with the available FDM machine and I need grater sizes. 

    Thanks for your kind attention.

    David Wells · North Dakota State University

    External sizing is not so important.  The 'correct' size is what fits the application.  The difficulty lies in structuring the internal sizing (i.e., porosity and pore size).  Here, one needs to learn what size channels are most conducive to osteoinfiltration.  Our studies suggest that about 4x to 8x cell diameter is most suitable.  However, these dimension may be sensitive to the depth of infiltration (of cells into implant) wanted.  Deeper infiltration seems to warrant wider initial openings.  Another very important factor is the continuity of internal pathways.  Sharply twisting pathways seem to be somewhat inhibiting to deep osteoinfiltration.  Overall porosity seems to be more influenced by needs for structural strength and stability.

  • How to identify 'parasitism' in practice?

    The definition of parasitism implies that some living beings named 'parasites' take energy for individual survival at costs of living beings named 'hosts'.

    Terminology 'host' might give the impression to 'non-specialists', like tourists, that parasites are always mentally invited to take energy. In addition, humans often give 'energy' (e.g. blood) without knowing the true identity of receivers, thus without having access to perceived costs or benefits involved.

    How to make practically a distinction between 'taking', 'giving' and 'sharing' in Parasitology or Sociology when mental states of actors are ignored?

    Francesca Cansani · University of Applied Sciences and Arts of Southern Switzerland

    Parasitism as it is called

    1. Today, and

    2. as it is perceived both by the Object of Parasitism,

    3.1. and by any Observer which is neither affectionate to the so called Parasite, nor to the Object of Parasitism, or,

    3.2. which is affectionate to the Object of Parasitism,

    4.1. can be considered the Phenomena where the Parasite take Profit of a Situation, harming the Object of Parasitism unconsciously, or

    4.2. consciously, which is when the Parasite meets an Object which needs a Hand,  instead of asking itself ''how can I help?'', the Parasite says ''let's take Profit from the Object's Weakness or Situation of Need!''.

    5. The main Question remains: is the appearent [see 2. and 3.] Parasite conscious of what it is doing? Is the Parasite conscious that it is harming the Object of Parasitism [the Host]? Isn't it conscious? [See 4.]

    6.1. If the Answer is that the Parasite is unconscious [see 5.], maybe the Parasite should not be called a Parasite anymore, or an Adjective should be added to the Word which describes it [i.E. unconscious Parasite],

    6.2. if the Answer is that the Parasite is conscious [see 5.], maybe the Parasite should be called a Parasite, indeed, and maybe an Adjective should be added to the Word which describes it [i.E. evil/unethical/amoral/immoral Parasite].

    ---

    Dear Marcel, you asked about BloodTransfusions: I must admit that I've lately asked that to myself as well.

    I have no Answer, and though,

    I am sure that within the Medical Domain there are sincere and honest  Practices,

    as well as lucrative. let's say, less sincere and honest ones.

    The Question of the Object of Transfusions [the Donor], which cannot be called a Host [like the Being UNVOLUNTARILY hosting a Parasite] is:

    do I have to keep giving my Blood, because of the sincere and honest Practices,

    or do I have to quit giving my Blood, because of the lucrative and less sincere and honest ones?

    While the, let's say, Parasite in this Case is or the honest Receiver [and therefore he/she is not a Parasite: the Donor has freewillingly given his/her Blood],

    or the dishonest Receiver, which is practically one with the dishonest Practice [see above], [and therefore he/she is a Parasite (see 6.2.)].

    ---

    As I already stated in another Comment, the Aim ''Equanimity'' may guide us!

    Hopefully, such a, let's say, Mantra, might help us to resound [please refer to the Resonance Principle] with it and to meed equanimous People and Situations and Practices.

    ---

    Equanimity: where is it, who practices it, what about Parasites and Hosts [is their, let's say, Relation or OneWay Relation, based on the above mentioned Mantra, or else?]. How could an equanimous World look like? From the Point of View of the Subjects, of the Objects and of the Observers [if not even, of, let's say, God (an impersonal supernatural Principle, which vivify us and surpasses us)]?

    Sorry for the pragmatic versus philosophical versus spiritual Mix: I can't help without.

    ---

    Happiness inside/outside to Every1.

  • Waleed Khadr asked a question in Molecular Biology:
    Molecular biology

    can you please any one explain for me the best protocol for synchronization of  C.elgans.

    thanks

  • Elnaz Ghanbary added an answer in Stereo Vision:
    How can I measure 3D coordinates of a target, using a camera?

    Hello,

    How can I measure 3D coordinates of a target, using a camera?

    I have an emphasis on depth information.

    Should I just utilize stereo vision (two cameras)? Isn't it more difficult to calibrate two cameras than one?

    Can I use any other ways? Can you please assist?

    Elnaz Ghanbary · University of Tabriz

    thank alot

  • Do you have experience in and are interested in a possible collaboration in research on "approaches to learning"/ "approaches to teaching"?

    Dear colleagues, 

    I am interested in conducting research on the "approaches to learning" (SAL, Students' Approaches to Learning, Biggs, Marton, etc.), or "approaches to teaching" (Trigwell, etc.) line of research  with international partners, or maybe participating in a project already underway. So far I have analysed the approaches to teaching of secondary education trainee teachers in my home country (Spain), but would like to broaden my horizons. Would anyone be interested in a possible collaboration?

    Alva Helena de Almeida · Unified Health System, São Paulo, Brasil

    I have experience in teaching adults, health workers, from the view of the critical pedagogy. I am interested on a colaboration.

  • Muhammad Anwar added an answer in Cooling:
    Why is radiation pressure force non-conservative?

    Due to the non-conservative nature of radiation pressure force, it can be used for the cooling of atomic motion.

    Muhammad Anwar · National Institute of Lasers & Optronics

    In magneto-optical traps, the radiation pressure forces are responsible which arise from the spontaneous emission processes and therefore the terms like non-conservative and dissipative etc. In optical dipole traps, the forces are reactive and arise from the stimulated emission processes and therefore these are conservative force traps. Stephen! we are only discussing and sharing how we look at the processes. We might be different and even wrong. And one should not be impressed by very high impact factors and also one should look down upon the new researchers. Thanks and Good Luck.

  • Marco Laredo added an answer in Aging:
    Does anyone have a model of studying aging in cell lines?

    I am attempting to study the effects of aging on a range of proteins in specific cell line. Can anyone suggest any method they may have used in the past?

    Thank you

    Marco Laredo · Center for Research and Advanced Studies of the National Polytechnic Institute

     Hi!

     I work with fibroblasts from patients with Hutchinson-Gilford Progeria Syndrome (HGPS), you can get them from the Coriell Institute.

    https://catalog.coriell.org/0/Sections/BrowseCatalog/DiseaseDetail.aspx?PgId=403&omim=PRO17667&coll=  

    I hope this helps!

  • Giorgio R Merlo added an answer in RNAseq:
    How to perform RNAseq statistics?

    RNAseq delivers gene expression data from experiments with several biological replicates for two or more conditions. Once you have the processed gene expression data comparisons between conditions can be performed and the genes selected should be weighted for the probability that they appear differentially expressed by chance. Which approaches to do that are there? Is Significance Analysis of Microarray (SAM) the right choice?

    Giorgio R Merlo · Dulbecco Telethon Institute

    Ulli, io non sono esperto di questo, however there is a guy quite knowledgeable on this. Can contact him, he does RNaseq analyses every day.

    raffaele.calogero@unito.it

  • Patricia Balaresque asked a question in Chimpanzee:
    Are the arms of the Y-palindromes correctly phased for chimpanzee?

    Hello everyone, Are the arms of the Y-palindromes correctly phased for chimpanzee? For humans, since physical and deletions maps exist, arms of the Y-palindromes are phase along the chromosome, but what about in chimpanzee?Thank for your answers.

  • Can someone help with converting DICOM files to NIFTI?
    Using dicom2nii or MRIConvert to convert DICOM images to NIFTI I get an error about unsupported transfer syntax. MRIConvert website states that it only supports certain syntaxes (1.2.840.10008.1.2 and 1.2.840.10008.1.2.1). The images I have specify UID starting with 1.2.840.11.... Did anyone have a similar problem and perhaps found a solution?
    Amir Zolal · Technische Universität Dresden

    Mohamad:

    I don't know what Olga uses but for me

    find . -printf "~/dcmtk/bin/dcmdjpeg %p %p \n" |sh

    run in the DICOM directory works anytime without the need for a script. Do substitute the path for dcmdjpeg with your own though. 

  • Carlos G Perez-Garcia added an answer in VMAT:
    Why in western blot, every protein that I have checked appears in the same molecular weight?

    I have checked Cg A, Vmat 2 AQP4 from CSF.. and all of them appears at 50KD. I don't know what is going on.

    Carlos G Perez-Garcia · Salk Institute

    Hi Leandro, you are probably detecting non-specific bands, you can start by changing the dilution of your secondary antibody, also use washing with TBST and either BSA or powder milk, that one works fine for me. A more suitable option is to use a light chain specific antibody to avoid detection of the heavy chain ~ 50 KDa that always give you a lot of noise. Goodluck. Saluda a Agustin de mi parte, un saludo , Carlos

  • Does anyone sell extra fine point ethanol-resistant markers anymore? Ones that are truly resistant to 70% ethanol?
    Just to clarify, I'm not talking about the "fine" point markers. They are simply too large for putting a lot of material on the top of an Eppendorf. In the photo, it's the marker on the right, which was sold as "extra fine" but is seemingly no longer sold. I have tried a couple of alternatives that have ended up smudging when exposed to 70% ethanol.
    Nilgun Tasdemir · Cold Spring Harbor Laboratory

    I requested pen samples from Aspen Surgical and a rep was kind enough to send me some. I just tested them and the Securline Black Lab Marker (Fine tip. Ref: 1400-20-PDC) is the only pen I found to be ethanol resistant so far. Writes very nicely too. Fine tip not extra fine but still does a decent job. Definitely ordering some!

  • Hadis Motaghi asked a question in Decision Trees:
    Pruning of decision tree?

    do you implement pruning of decision tree in mattlab?and if possible, please help

    Thanks?

  • Z. Osmanov added an answer in Telescope:
    Does anyone know what is the minimum level for detectability of PeV photons by modern telescopes?

    One of the important questions concerning this topic is to know sensitivity of instruments - the minimum detectable flux.

    Z. Osmanov · Free University of Tbilisi

    I'll have a look the website of the conference when they put proceedings and publications. Many thanks for your kind attention and such a useful information. 

    Greetings

    ZO

  • Jerzy Mierzwa added an answer in Water Analysis:
    Dear friends, which brand Of IC systems is better, Dionex or Metrohm or another brand

    I want to do some water analysis and the results should be in ppb concentration , and I want to see which brand of IC is better or another system for analysis?

    Jerzy Mierzwa · Tennessee State University

    "thanks for all, actually, I worked on Metrohm system before but its results were in +- 5% with standard samples"

    There are several factors influencing analytical precision. So, it is not necessarily an instrument problem.

  • Samrina Ahmed added an answer in Mangroves:
    Can anyone provide methodology for crude leaf extract for antioxidant enzyme assays: SOD, CAT, POD, and non-enzyme antioxidants: ascorbic acid?

    I am working on enzymes in Mangrove plant. Different research papers show different types of procedure. I need easy one. Also,

    *Storage methods

    *How I'll confirm that extraction is 100% OK for my further estimations.

    *How much amount of extraction is required for determination of one enzyme.

    Samrina Ahmed · University of Karachi

    Thanks you both of them

  • In your country what energy source (residential use) is most used:NG or electric energy?Gas network has 100%coverage? What factors determine this?

    In São Paulo, the most important city in Brazil, there is a difference of nearly 100 years between the expansion of the electricity network and natural gas (NG) distribution pipelines.


    The gas only gained momentum since 2000, while the electricity followed the development of neighborhoods.


    The use of electricity Is still the predominant, based on the following factors:
    -The energy matrix based on the use of hydropower and on the electricity that they generated;
    -Electric energy tariff is still lower than gas;
    - Many houses and buildings have no facilities adapted to use gas.


    There are reports / papers on this subject?


    Thank you for helping!

    K. Sudhakar · Maulana Azad National Institute of Technology, Bhopal

    Both gas and electricity equally contributes to the residential sector in India.LPG gas is used for domestic cooking and electricity for lighting and conditioning

  • Maria Bettencourt Pires added an answer in Cadaver:
    Does anyone have experience with determining the Q-angle on cadavers?

    Good day.  I am interested on how one can accurately measure the Q-angle on cadavers, if this is even possible.  Also, if possible, state the name of the article that supports this notion.  

    Maria Bettencourt Pires · New University of Lisbon

    Thank you, dear colleagues, for presenting such interesting issues.

    As an anatomist, working in a warm European Country, it occured to me that maybe your problems will improve, if you modify your embalming technique, in the sense of avoiding dehydration of tissues, such as which is provoqued by formaline.

    In the Department of Anatomy of the Lisbon Nova Medical School, we have been testing and developping new embalming techniques that keep corpses with fresh appearance for a long time. Our embalming technique,with a modified mixture of Theil was improved with the innovating addition of an embalming perfusion pump developped in our University, which permits the perfusion of tissues with a computer assisted simulation of cardiac rythm. 

    This would allow you to spend more time for your studies in cadavers with a «near-live» embalmed state, as it permits us to use them in «hands-on» post graduation courses and surgical training courses, as we currently offer in our department.

    I reffer an article on these innovating techniques, by the Head of my Department, J. Goyri-O'Neill:, that you can find on Research gate:

    https://www.researchgate.net/publication/244479992_Improvement_of_the_embalming_perfusion_method_the_innovation_and_the_results_by_light_and_scanning_electron_microscopy

  • Does the surface roughness have an effect on thermal properties of thin film thermoelectrical materials?

    Since sputter deposition belongs to the group of plasma-assisted processes, next to neutral atoms also charged species (like argon ions) hit the surface of the growing film, and this component may exert a large effect. Denoting the fluxes of the arriving ions and atoms by Ji and Ja, it turned out that the magnitude of the Ji/Ja ratio plays a decisive role on the microstructure and morphology obtained in the film

    Tarik Ömer Oğurtani · Middle East Technical University

    Dear Dr.Skvortsov;  Thermal [W/ (m.K) and electrical [1/ (ohm.m)] conductivities are specific quantities, their values are independent from the dimensions and the shape of the material under questions. Phonon part of the surface thermal resistivity increases (conductivity La decreases) with the surface roughness. According to the formula I have cited  previously ZT  which is  inversely proportional with the thermal conductivity increases with the surface roughness!!!  

  • Philippe Joly added an answer in Freezing:
    How freeze MC3t3 cells

    proliferated cells are harvested. How do I freeze them?

    Philippe Joly · Université de Reims Champagne-Ardenne

    Dear Patricia

    My Protocol used with K562 cells HL60 et murine cells :


    Wash cells
    Put in: culture medium + 20% Serum fetal calf + 10% DMSO (dimethylsulfoxide)
    Surround cotton tube and freeze slowly at -80 ° C
    Two days after nitrogen liquid (-180 ° C)

    BUT As I do not know this line (MC3t3 cells) I would do a test

  • Alex Ray asked a question in Tissue Sectioning:
    Has anyone successfully stained for dendritic cells in paraffin-embedded tissue sections? If so, what/which marker(s) did you use?

    I am trying to stain for different immune cells in paraffin-embedded skin sections from mouse. We would like to stain for dendritic cells in addition to the other cells we have antibodies for.

  • Pedro M. Alcolado added an answer in Ecology:
    How can one quantify the heterogeneity in surface profiles?

    I welcome answers from different disciplines and for all different scales from (nano-micro) body part of an organism or metal surface to surface heterogeneity in topographic features

    Pedro M. Alcolado · Instituto de Oceanología

    I like the simple way of AGRRA methodology. From  10 m long transects  (each meter marked) the maximum Reef Relief is obtained within a 1m radius of the 1m-, 3m-, 5m-, 7m-, and 9- m marks along the transect line. For doing that, at each one of the 5 points measure the height of the tallest coral or reef rock above the lowest point in the underlying substratum. In other words, five positions are selected and within 1 m diameter of these positions, a measure si made from the deepest part of the relief and highest one using a pvc bube marked in cm. After a number of 10 m transects a number of 50 measures have been taken, which are averaged and  Standard deviation is calculaded. With these measures, rugosity can be compared among sites. Excuse me for my imperfect Englsh.

  • Shankhadeep Chakraborty asked a question in Modernity:
    Can arranging science debates be a good way to nurture the science talents in institutions?

    Science fairs, quizzes and exhibitions are already proved to be potential agents of nourishing the talents of students and encouraging them towards more discoveries in Science. Can Science debates be another such useful agent in modern day world?

  • What is the level of pain in post operative patients?
    Following major surgery.
    Richard E. Haas · WellSpan Health, York PA

    Postoperative pain is challenging, and is usually ranked with a Likert type scale ("Rate your pain from a level of 0 [no pain] to 10 [intense pain]") There are many ways to manage it including intravenous narcotics, non-steroidals, and pre-emptive analgesia. Preoperative nerve blocks will also improve pain relief.  I am attaching a brief article on opioids which is a bit dated, but you may find useful. 

  • Hasina Randrianaly added an answer in Ammonoidea:
    How can I calculate the length of the last whorl of ammonite, starting from diameter?

    The shell of ammonite may be considered a logarithmic spiral.

    Does some way exist to find the length of last whorl knowing the external diameter and the umbilical diameter? What kind of other measurements do I need?

    Hasina Randrianaly · University of Antananarivo

    Hi Andrea , If it is the last whorl, I think it is big enough