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  • Thomas Walther added an answer in GaN:
    What happens to GaN film on sapphire or Si 111 when it is sulphidised at 850°C?

    Is GaN film stable at such high temperature in sulphur ambience?

    Thomas Walther · The University of Sheffield

    That may depend on the environment you use and for how long you treat the sample. Kumar et al., Current Appl. Phys. 14:3 (2014) 491-5 showed dipping GaN samples in ammonium sulphide diluted in aqueous and alcoholic solvent produced increased Schottky barrier heights at room temp. For long, high temp. anneals S may diffuse into the GaN and eventually through the GaN into the Si substrate and cause reactions there.

  • Asma Mansoor added an answer in Poetry Writing:
    Can anyone suggest poems that deal with Human-Animal conflict, or similar other issues relating to animals / birds?

    I would locate reading of human-animal conflict in the broad purview of eco-aesthetics or ecocriticism. Poems that deal with the animal worls in my view most often contain an ecocentric worldview. When human-animal conflict arises, what actually happens is a conflict between two prominent worldviews, viz., ecocentric and anthropocentric. The changing patterns of urbanization, consumerism and materialism makes our world more susceptible to such conflicts. I think poetry is a suitable literary poem to search for expressions on such conflicts. Can anyone throw more light on this issue? 

    Asma Mansoor · International Islamic University, Islamabad

    Read "Pike" by Ted Hughes. He writes such poems with animals as his subject, but it also depends on how you define the word "conflict".

  • Gudrun Lang added an answer in HCC:
    What is the yellow/green pigment (PAP stain) in these macrophages from pleural fluid?

    I recently observed many macrophages containing yellow/green colored material in PAP stained pleural fluid cytology from a 46-year-old male patient who has a history of HCC with pleural effusion. He got TACE for the HCC several times. He also has liver cirrhosis due to HBV infection. Is this material bilirubin pigment? I have not seen this kind of pigment in pleural fluid cytology. Any comments or personal experiences to share please?

    Gudrun Lang · Allgemeines Krankenhaus Linz

    Have you done alternative stains on this material? Giemsa, PAS ? it would be interesting if this is a proper colour of the macrophages or just a matter of binding Orange G (out of the PAP-stain).
    If it is bilirubin, there is a stain called "Hall" or "Fouchet"  to show liver-pigments.

  • Simple random sampling with replacement applications?

    Can anyone share to me some applications of simple random sampling with replacement in real life scenario? to be more specific in agriculture where this design is used? 

    Muhammad Sohail Amjad Makhdum · Christian-Albrechts-Universität zu Kiel

    Plz find enclosed.

  • Sk Jahiruddin asked a question in NAMD:
    What is the main difference between equilibration and production run in NAMD?

    I am not understanding the parameters need to change in equilibration and production run conformation files. NAMD tutorials file always use "reinitvels" to equilibrate and that also in a same conformation file. Is the approach OK? Should I just take binvelocities from equilibration file and make a run? Should anything more to be changed? I'm attaching a sample conf file as provided in NAMD tutorial. Experts please help.

  • Khalid Iqbal added an answer in Health and Wellness:
    Is anyone working with patient communication skills training, particulary for adolescents?

    I'm working on curriculum for high school health and wellness classes.

    Khalid Iqbal · khyber teaching hospital

    Actually my work is on Type I diabetic patients and with positive family history. As far as counselling techniques and its effectiveness is concerned i can add.. for curriculum i have less experience.

  • Roman Kubrin added an answer in pH meter:
    Is there pH lower to zero and higher to 14 ?

    If we use pH meter for concentrated  strong acid, the pH comes in negative value.  However I did not experience more than 14 pH.  But is it possible, I like to know.

    Roman Kubrin · Empa - Swiss Federal Laboratories for Materials Science and Technology


  • What should be the weightage accorded to the list of publications in assesseing a teacher/researcher for selection/ promotion in service career?

    Millions of research publications have been reported containing erroneous/ wrong / false results (while still many such others might have gone unnoticed!).  Lot many of these have even been reported to have (proudly) enjoyed the reputation of winning various levels of recognition including globally prestigious awards.

    Keeping this in mind, should, in your opinion, the number of publications supersede (and negate) the entire gamut of one's contribution in deciding the suitability of a person for a job. It may further be kept in mind that such a selection (assessing the lifetime performance of a candidate through a 15-20 minute interview conducted by a 4-5 member team, all of whom need not themselves be suitable for participating in such a crucial process) has a potential to influence the entire course of life of all the candidates, whether selected or not).

  • Nicolaj Mahlstedt added an answer in Oil and Gas:
    What are the best choices for modeling sub-sea oil and gas release?

    Many scientists around the world have researched the field of oil and gas release in marine environment.

    What are the best choices for modeling of sub-sea oil and gas release?

    Nicolaj Mahlstedt · Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ

    It probably depends on the available data...

    Paper by Berbesi et al., it is uploaded here on research gate, perhaps you can find some good ideas.

    Methane leakage from evolving petroleum systems: Masses, rates and inferences for climate feedback


  • Marta B Evangelista added an answer in Macrophage:
    Any recommendations for assay kits to measure ROS in macrophages using FACS?
    I would like to measure general ROS levels in bone marrow derived macrophages using FACS. There are several assays around and I´d like to know which are easy and reliable. This one seems to fulfil those criteria: ENZO total ROS detection kit (ENZ-51011).

    Also, what´s the general view on plate-reader vs FACS based detection?

    Hi all. I am just reading this discussion over the measurements of ROS on macrophages and have a couple of questions as I am trying to interpret my data and why the assay I have used did not work out and I would be very happy if some of you could get back to me.

    @Steven: I have used to detect ROS production in naive monocytes as well as macrophages the CellROX Deep Red from Molecular probes that apparently it is possible to be used for fluorescent detection as well as for imaging analysis and FACS as well.

    In the lab, I've tried in 3D LPS stimulation 100 ng/mL for 30 min and did not get any good results.

    Then we tried to use in 2D 200 ng/mL for 24h stimulation.

    I saw you mentioned you have used 100ng/mL for 8h.

    Do you have any idea about this? Did you ever tried to use this CellRox and measure fluorescence only? Thanks!  

  • What is external and internal resitance, when the specicific ion is adsorbed in a porous material ?

    It is related to the pore diameter and the size of the ion which enter in to the pores of the material besides the surface adsorption. Usually the stirring increases the rate of adsorption in to the pores of the material.

  • Burhan Udin added an answer in Tourism Marketing:
    Can anyone suggest studies on self-regulation in the tourism market?

    E.g. there are tourism associations which provide rules for classification of hospitality enterprises, quality certificates for tour guides etc. I am interested in particular in comparision studies between such organizations and state regulation.

    Burhan Udin · Stie Perbanas Surabaya

    We can refer to regret and affective forecasting

    Wilson, T. D., & Gilbert, D. T. (2005). Affective forecasting: Knowing what to want. Current Directions in Psychological Science, 14(3), 131-134.
    Wilson, T. D., Wheatley, T., Meyers, J. M., Gilbert, D. T., & Axsom, D. (2000). Focalism: A source of durability bias in affective forecasting. Journal of Personality and Social Psychology, 78(5), 821-836.
    Zeelenberg, M., & Pieters, R. (2000). A theory of regret regulation 1.0. Journal of Consumer Psychology, 17(1), 3-18.

    Thought they may  fit with self-regulation.

  • Michael Patriksson added an answer in LINGO:
    For a beginner in Linear Programming, which algebraic modelling language do you recommend most? GAMS Vs. IBM OPL?

    I am a beginner in my field and I would like to formulate and solve a Mixed-Integer Linear Program to optimize a supply chain superstructure (facility location, technology selection, etc). What Algebraic Modelling Language do you recommend the most? It seems to me that IBM OPL and GAMS are the most frequently used in Literature , with LINGO just behind them. What do you think? 

    Michael Patriksson · Chalmers University of Technology

    For our computer exercises and projects we use AMPL, linked to CPLEX through model and data files. The syntax is quite natural, and we seldom - if ever - have any problems. 

  • Do dehydrated ginger rhizomes and dehydrated tea leaves contain glutathione?

    Some plants are known to contain glutathione. Do dehydrated ginger rhizomes and dehydrated tea leaves contain glutathione? Supporting literatures will be appreciated.

    Solomon Akinremi Makanjuola · Promasidor Nigeria Limited

    Hello Aldallal. Thanks for your response. You just confirmed my findings. I did a study to screen for glutathione in dehydrated ginger samples but the result was negative. 

  • Christina Stoeckle added an answer in Eosinophils:
    Do I need to add glucose to RPMI 1640 for eosinophils culture in a 12 well plate?

    I'm trying to culture eosinophils (from mice) in a 12 well plate in order to extract all proteins after 24h. I use RPMI 1640 without glucose. do I need to add glucose? What does everyone else do in order to keep them alive cause I don't seem to have enough proteins after bradford and I tried to double the amount of eosinophils in a well but still got the same results? Are they dying? What do I need to do in order to keep them alive?

    Hadas :)

    Christina Stoeckle · Universität Bern

    Dear Hadas, I recommend counting the cells before plating at least 1 Mio cells/condition. This should give you enough for a Western blot. Also, please keep in mind that PMNC contain neutrophils as well as eosinophils. The easiest way to check your eosinophil vs neutrophil content is to do a cytospin followed by e.g. DiffQuick staining.

    Good luck

  • What are the differences between pragmatics and discourse analysis?

    Does any of them include the other? If not, how much do you find them related?

    Antonella Strambi · Flinders University

    Am I the only one who believes that discourse analysis is a method, or an approach, while pragmatics is a discipline? Please don't take this as a challenge, it's a genuine question. I may have misunderstood this relationship for years :-)

  • Ji Ryong Cho added an answer in Surfaces:
    How do you estimate the diameter of a surface dent left by a ball pressed against a flat surface?

    Consider a small ball made of very hard material and pressed against a flat surface made of a relatively soft material. When plastic deformation occurs, the ball leaves a circular dent on the flat surface. Given the magnitude of the contact force, is there an analytical model to estimate the dent diameter?

    If not, which software is recommended for this type of simulation?

    Ji Ryong Cho · Inje University

    Hi, again. I've checked your reply. 

  • Ricki Allardice added an answer in Earthworms:
    Vermi-compost vs. thermo-compost: which one is better as a soil amendment?

    It is a common belief that vermi-compost (compost made with earthworms) is better than thermo-compost (microbial decomposition with temperatures as high as 60 0C)  in quality and soil amendment properties. I wonder if there is strong scientific evidence to support such a claim.

    Ricki Allardice · Stellenbosch University


    I've attached a paper that should answer your question. The authors compared composing and vermicomposting of municipal biosolids as well as backyard vermicomposting. They found that vermicompost contained higher mineral nutrients, increased microbial populations and activity in the soil and increased rye grass biomass when compared to thermophyllic compost. The authors do also state though that comparisons cannot be drawn across the board, since source material plays such a key role.  However other authors have found composts to contain more mineral nutrients than vermicompost. I think it is safe to say though that vermicomposts contain a greater abundance and diversity of microbial life than thermophillic composts. 


    I agree that leachate derived from vermicomposts is rich in mineral nutrients, however it is also anaerobic, providing a good breeding ground for many plant pathogens. If this can be overcome through aeration perhaps then this resource can be utilized more effectively? Leachate is also very rich in dissolved carbon and humic/fulvic acids. Currently this is an aspect of vermicompost research that has been largely ignored but definitely warrants further attention because if you combine the potential benefits to plant production of leachate and vermicompost you may well have a product that is highly competitive with chemical fertilizers. What do you guys think?

  • Faez Iqbal Khan added an answer in Gromacs:
    With regards to Gromacs Radius of gyration, how do I analyse the data?

    Does anyone know how to analyse the plot obtained from gyration? I know what it means but I'm not sure how to use this measure or interpret data? I run MD for a protein in complex with DNA.

    Faez Iqbal Khan · Durban University of Technology

    g_gyrate -s XXXX.tpr -f XXXX.xtc -o gyrate.xvg

  • Remi Cornwall added an answer in Annular Flow:
    Why does my MATLAB 1D simulation of two-phase annular flow in a vertical 9.5m pipe stop at less than 1m?

    After coding the the mass and momentum conservation equations for a 1D air-water annular two-phase flow model in a 9.5m vertical pipe using a three-fluid model (for liquid film, gas, and droplets) in Matlab and solving with the stiff ODE solvers ode23s and ode15s, the integration only proceeds for less than 1m of the 9.5m. Has anybody done similar work, and any suggestions on how to get better results? Thanks.

  • Johan van der Dennen added an answer in Sculpture:
    Do you know any masterpieces of art which are devoted to anti-war themes?

    One of the main tasks is to cultivate peacemakers. Anti-war arts (painting, sculpture, literature, music, photo) can be helpful in upbringing future generation. Cultivating a culture of peace through awareness of genius message (implicit and explicit) is important in schooling. We are going to research the sources, organize the conference and stage one of the creative works. We will be thankful for every contribution.    

    Johan van der Dennen · University of Groningen

    Besides the well-known Goya's "Los desastres de la guerra", and Picasso's "Guernica", there are a number of lesser-known anti-war paintings, which I attach: (1) Pieter Bruegel's "Dulle Griet"; (2) a series of engravings by Callot; (3) Otto Dix "Triumph of Death"; (4) Peace allegories by Rubens and Tintoretto; and (5) Da Vinci's "Pazzia bestialissima".


  • How do I use amber to add NaCl?

    Hi, everyone

      I want to simulate a biomolecular system with certain ionic strength using amber software, but the tutorial did not tell me how to add NaCl using tleap. Someone told me to use this command "addions REC Na+ 5 Cl- 5". And another one told me to use" addions REC Na+ 1 Cl- 1

       addions REC Na+ 1 Cl- 1

       addions REC Na+ 1 Cl- 1

       addions REC Na+ 1 Cl- 1

       addions REC Na+ 1 Cl- 1". That is, it has to add the ions one by one. So, which one is right, or whether neither is right? Can anyone give me some suggestion?

    Gloria Fuentes · RIKEN

    you could use the autoionize plugin in VMD


    and convert the files to amber format

  • Fredrick Johnson J added an answer in Glass:
    How to measure the temperature inside the vacuum chamber from outside through viewing port.

    I have a vacuum chamber and i want to measure the temperature inside. I have KF-50 flange glass viewing port but glass absorbs IR and IR thermometer does not works through glass. Can anyone suggest how can I measure the inside temperature (Temperature of Interest: Room temperature to 350 Degrees Celcius).

    Fredrick Johnson J · Indian Institute of Technology Madras

    When measuring the temperature of glass with an infrared thermometer, both reflectance and transmittance must be considered. By carefully selecting the wavelength, it is possible to measure temperature of both the surface and at a depth of your vacuum chamber. When taking measurements below the surface, a sensor for 1.0, 2.2, or 3.9 μm wavelength need to be chosen. You can try with the fluke non contact type thermometers where the above conditions will satisfy.  

  • A. Sepehri added an answer in Cosmology:
    Can the initial singularity be removed from cosmology models?

    In a rather old paper, Michael Heller argues that in certain cases it is possible to remove the initial singularity from cosmology models. He discusses b-boubdary and noncommutative geometry. So what do yo think?

    A. Sepehri · Shahid Bahonar University of Kerman

    It seems that both Big Rip and Big Bang singularities can be removed in string theory. For example, if we construct our universe in string theory, we can predict all future events.

  • Jose-Luis M. Abboud added an answer in Gaussian:
    Hi, why is the proton affinity of ammonia higher than water? Also what is the significant aspect needed to be discussed?

    I did calculations by using G2 method and the result was 853.60 kJ/mol for amonia and 688.36 kJ/mol for water and the experimetal date of amonia is 853.6 kJ/mol and for water 691 kJ/mol ... I used G2 theory due to its  high accuarcy and the base was Optimize + Vib Freq - Gaussian 

    Jose-Luis M. Abboud · Spanish National Research Council

    Dear Dr. Albadran,
    Yes indeed, calculations with the G-n methods generally provide excellent agreement between experimental and computed thermodynamic data. However, reproducing these results do not give an "answer" to your questions. I think what you need is some sort of " conceptual model". I see an increasing tendency to believe that computations alone have some sort of magic power and this is no good.
    I suggest you to consider "old fashioned" things such as ionization energies, Pauling's electronegativity scale, etc.
    Good luck!

  • Regis Orobtchouk added an answer in Waveguides:
    In the layout optimization of an EO Modulator, is the effective area to be optimized related to the optical field or to the applied electric field ?

    I have to design the layout of an electro-optic modulator using a slot waveguide structure. In the papers from Christian Koos (Karlsruhe Institute of Technology), in particular Optics Express 15, N 10, p 5976 (2007), the modal effective area Aeff is the target of the optimization in order to increase the nonlinear effects. In the case of a slot waveguide, the Aeff within the nonlinear slot must be minimized. I'm wondering if this Aeff is related to the travelling optical field or to the applied electric field at the electrodes.

    Regis Orobtchouk · Institut National des Sciences Appliquées de Lyon


    If you look at the mode coupling theory, the variation of the propagation constant of the optical mode is proportionnal to overlap between a first quantity (a tensor of  the variation of the permittivity multiply by the electric field of the optical mode (Eopt)) multiply by the complex conjugate of the electric field of the optical mode (E*opt).

    The variation of the permittivity is given by the product of the electro-optic tensor and electric field of the RF signal (Erf). If we use only the r33 coefficient, the variation of the propagation constant is proportional to r33*Erf*Eopt*E*opt.

    This meens that optimization of the modulator involve the maximization of the overlap between the RF and optical mode.


  • Has anyone tried to use self-adaptation and self-organization at the same time in multi agent systems?

    Self-Organization has a bottom-up process and Self-Adaptation has a Upside-Down process. It may cause kind of conflict.

    Hadaytullah Hadaytullah · Tampere University of Technology

    Self-organising systems are one specialised branch of self-adaptive or self-* systems. A self-organising system is self-adaptive system too. Perhaps, you meant something else by "self-adaptive" in your question?

  • Thomas Walther added an answer in Thin Films:
    How can I cut glass substrates for coating?

    I make thin films and I use glasses as substrate. A single grid's dimension in my evaporation system is 16mm x 6mm. I work in 10-6 Torr vacuum.

    How can I cut my glasses with rectangular geometry?

    Thomas Walther · The University of Sheffield

    It's important the scratch extends to one side corner (where the crack should initiate from) and that you place the glass UPSIDE DOWN onto a slightly flexible substrate (e.g. a piece of cardboard or strong filter paper) rather than directly onto the flat and hard desk surface.Place another piece of cardboard on top and press hard on the front until you hear a click. Good luck.

  • Nada A Rasheed added an answer in LBP:
    What is the main idea behind using LBP for face recognition?

    What is the working technique of LBP for face recognition?

    The idea behind using LBP features is that the face images can be seen as a composition of micro patterns which are invariant with respect to monotonic gray scale transformations. Combining these micro-patterns, a global description of the face image is obtained.

    Nada A Rasheed · National University of Malaysia

    Hi Rakesh,

    you can depending on the color feature, where every one has property color different from to other ... good luck