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  • Hafid Soualhine added an answer in Vaccines:
    Can BCG be used as a therapeutic vaccine ? Can booster shots be used ?

    Very rare studies are reported that have investigated role of BCG as therapeutic vaccine after TB infection. Can Single or booster dose of BCG be used as therapeutic vaccine alone with drug combination?

    Hafid Soualhine

    Aeras in Bethesda are trying to prime/boost the BCG immunization using BCG and recombinant protein expressing AG85 A and B, and rv3407.

    By the way ther are looking for a scientist in this field 

  • Janet Hanson added an answer in ESL:
    What are the theoretical and empirical relationships between developing a multicultural view in schools and a growth mindset?

    Researchers recently focus on studies for developing growth mindset in schools. A review of the literature suggests the processes and variables involved in a growth school mindset may be similar to those that develop a group open to a multicultural view in schools. Does anyone have articles referencing studies connecting multicultural views in schools or ESL teacher development with Dweck's concepts of growth school mindset? Thank you in advance.

    Janet Hanson


    I appreciate the new resource you provided and the many kind words you have given me. I will read the resource and am certain I will find it useful and enlightening as always.

    Kind regards,


  • Bryan Gordon added an answer in Rock Art:
    What do you believe is the most reliable and valid means to date rock drawings (petroglyphs)?

    Do you believe in portable XRF dating of desert varnish?

    Do you think that associated dates for single component sites spatially associated with the rock art are reasonable?

    What techniques have you used?

    How have you attempted to obtain chronological controls?

    Bryan Gordon

    Well said, Alicia: Each pictograph or petroglyph must be evaluated for possible dating on its own merits. I chose micro-stratigraphy because most people can do it with very simple equipment. Bryan.

  • Roberto Fiorenza added an answer in Water Splitting:
    How do I calculate the quantum efficiency in a typical photocatalytic water splitting experiment?

    The formula is:

    QE= 2 (number of evolved hydrogen molecules) / number of incident photons.

    1. In particular how determinate the number of incident photons? 
    2. There are some review or papers that reported the typical QE range?
    3. Some papers give the  hydrogen production results in umol/h other in mmol/h other in umol/gcath, what is the correct way?
    4. I have made some exsperiment with the volumethic method but I obtained results of hydrogen rate in mmol/h. A lot of papers are on the contrary in umol/h. Considering that I didn't use a sacrificial agent what mistakes Can I have made?
    Roberto Fiorenza

    Thank you for your useful response.

    To calculate the H2 rate I oblviously considered that the Vtot= VH2+ VO2 and that VO2= 1/2 VH2. So VH2= VTOT* 2/3 considering the density of H2= 0.0899 gr/l I have the moles of H2....but obtaneid mmol

    Maybe there are other parametres that I haven't consider.....

  • Ryan Denomme added an answer in Protein-Peptide Interaction:
    Why does protein-peptide interaction show significant binding in dot blot analysis but fails to show it in Surface Plasmon Resonance (SPR)?

    Dear All

    No binding between 38kDa protein and 12AA peptide was demonstrated using Surface Plasmon Resonance (SPR), whereas specific binding and strong interaction was observed in Dot Blot analysis .
    What are the reasons you can think about that showing positive results in Dot Blot but not in SPR?



    Ryan Denomme

    Hi Avner,

    In our experience that should not be too small to measure on most SPR instruments. The more important parameter is the ratio of the molecular weights of the analyte and ligand. For your case, 1200Da/38,000DA = 0.032. So the amount of response you can expect for perfect 1:1 binding is 0.032 * amount of ligand immobilized. So for example if you immobilized 1000 RU of ligand you should expect 32 RU max response from your analyte. You can use this to estimate if you are below the detection limit of the instrument based on how much ligand you have immobilized.  

    If you are in the detectable range and still not seeing any binding, you could try changing the density of ligand (higher and lower), to see if this has any impact. Definitely trying other types of immobilization is another thing we would suggest. You could also try changing buffer conditions. Maybe there is some kind of charge repulsion between your analyte and the chip surface, so adding more salt might help, just as an example.  

  • Jacek Wydrych added an answer in Employee Timetabling:
    Can someone recommend me software that can be downloaded for preparing composite timetables for courses ran in at least four faculties?

    Timetabling for courses run each semester in the various Departments of the University has always taken us days. Does someone know of a software that can help us fast tract our timetabling for each semester? We have developed one, but it has not been too helpful.
    Education, timetabling

    Jacek Wydrych

    Good day

    Staff of My University (Opole University of Technology), use program celcat.


    Working examples you may check on our site:


  • سليمان الحزار asked a question in Soil:
    Can someone to get answer for these question?
    1. determine factor of safty of slope
    2. assuming drained soil conditions
  • Stam Nicolis added an answer in Quantum Gravity:
    Is there any theory of quantum gravity which is fully constructive, i.e. explains curved space-time?

    Does any current candidate theory of quantum gravity aim to, or claim to, construct or explain the curvature of space-time?

    My understanding is that quantum gravity theories are classified as background dependent or independent, according to whether they are formulated such that the depend on the shape of space-time or not.  This is *not* what I am asking.  I am asking whether they give an account of the cause of curvature of space-time.

    Stam Nicolis

    Discretization of spacetime requires a prescription for summing over the discrete geometries. This has been extensively studied for many years and the results are that a scaling limit, for four dimensional gravity, seems quite elusive. The scaling limit of this procedure would amount to a quantization of gravitational fluctuations.   There's no point in discretizing spacetime other than the description of quantum fluctuations-the statement is grammatically and syntactically correct, but empty of any content otherwise.  A sharp cutoff would break diffeomorphism invariance for gravitational interactions and Lorentz invariance for the other interactions-the effects would not remain confined to trans-Planckian scales. In fact what Sakharov does in the paper is identify one energy (or length) scale, where quantum and gravitational effects become comparable. However a cutoff does not imply that spacetime becomes discrete at that scale. It simply implies that, hitherto, unknown effects haven't been taken into account. 

  • Hafid Soualhine added an answer in Macrophage:
    How can we explain the role of mycobacterial proteins altering cytokine profile of host and increasing intracellular survivability of mycobacteria?

    We are working on two Mtb proteins : one induces IL6& TNF-a, 2nd protein induces IL10 & reduces IL6, TNF-a level when interacted with macrophages, both proteins helps Mycobacteria to  survive inside macropahge. how can we explain this?

    Hafid Soualhine

    Hi Kumar,

    How do you assertain that both your proteins helps mycobacteria to survive ? did you measure the bacilli viability or cfu count ?

    If yes, there are several pathways involved, phagolyzosome maturation, several proteins produced or induced by Mtb to escape the maturation of this compartment, or the oxidative iNOS, or may be autophagy. Also some signaling pathways like Jak Stat,  TLR, NOD1 and 2.

    You can target each intracellular pathway to look where your proteins act exactly, if your proteins are not known to interact in the littérature it's interesting to verify.

    Look to our publications  to see some examples (deghmane et al.2007 and  Sun et al.2008)

  • Levan Tielidze added an answer in Trace Elements:
    Are there any books or articles about the basalt alteration in the ocean?

    I am willing to do some researches about the different kinds of alterations in the basalt in the ocean. And I want to know if there are some books or articles describing the changes of REE, isotope or major,trace elements during the alteration processes

    Levan Tielidze


    You should find

    "Oceanic Basalts" book

    Edited by Peter A. Floyd. Springer, 1991

  • Gert Nolze added an answer in Metals:
    Any advice on EBSD - pattern quality?

    What are the possible reasons of unvisibility of EBSD pattern? I have measured EBSD on substrate and subsequently on deposited layer (by PVD). There vere only some areas where the Kikuchi lines were visible (and indexed). The measurements were performed on as-deposited layer (with no treatment). It is not clear for me the reason why somewhere the kikuchi lines are quite clearly visible and on the other place they cannot be detected at all. I suppose that the layer should not be amorphous. Moreover the indexed areas have preffered orientation. I know that there are some factors influencing the pattern quality (e.g. dislocation density). Is it possible that the bcc metal has so much better conditions for diffraction in certain orientation? Or is there another possible explanation of such phenomenon?

    Gert Nolze

    You forget a very serious problem. If electrons interact with the material they loose energy and do not contribute anymore to the Kikuchi patterns visible on the screen. They exist (interfering with electrons of a comparable energy) but the major signal comes from electrons of slightly less energy as the initial. This is one reason why (visible) Kikuchi patterns are comparatively weak on a big background. On the other hand it means that only electrons very close to the surface can fulfill this condition and this again tells you that the bubble you mentioned is not that important as you think. it is existing, but the effective size for the formed signal is clearly smaller.

    As I told you, the map collected 3 years ago was measured at Ti with 20kV, 80nm step size and a hit rate which is higher than 90%. It is the microstructure after spark erosion of Ti, therefore the different phases and the bend surface. And the literature gives enogh examples where microstructures have been scanned in high resolution. I don't think that I need to bother you with my own measurements. Nevertheless, I attached a link where framboidal pyrite has been scanned with 60nm step width. And such measurements have been done by the Liverpool group ten years ago as well at the same sample...and it was C-coated! FeS2 should be comparable to Ti and no exclusive material. As you can see, we even can recognize without any problem a non-existing 4-fold symmetry for the cubic phase. If you need more examples...no problem. Minerals, meteorites, metals and alloy...whatever you want :-).   

  • Sergei A. Ostroumov asked a question in Aquatic Ecology:
    What is the cost of good freshwater?

    When I asked this question, nobody gave me a clear answer.

    Key words: water quality, water supply, monetary assessment, economics of natural resources, aquatic ecology, unsolved problems, water reslources, freshwater

  • Levan Tielidze added an answer in Paleoceanography:
    Can anyone provide a reference for age profile data of the IODP 311 Expedition?

    Can anyone provide a reference for age profile data of the IODP 311 Expedition?

    Levan Tielidze

    Hi, maybe you can find some interesting for you



  • Sergio Kogikoski jr added an answer in PLGA:
    What is the affect of water in PLA, PLGA and PCL gels?

    I would like to have your opinion. 

    I would like to prepare PLA, PLGA or PCL gel. I need to add some water (not necessary a big amount) in the organic solvent used to dissolve polymer.

    I will dry the gel using supercritical CO2 or lyophilisation. 

    What do you think the addition of water will induce as result?

    Sergio Kogikoski jr

    You could think that water would first form the hydrogel that you are preparing, and second it could probably enhance the intermolecular bonds formed in your gel, what could make everything a little bit more strong, is that a good answer? or do you need something more specific?

  • Sasa R. Pavlovic added an answer in TRNSYS:
    How can I model solar parabolic Dish collector in TRNSYS?

    How can I model solar parabolic Dish collector in TRNSYS?

    Sasa R. Pavlovic

    Dear Sir, thank you very much...

    I think it's very difficult to model this system in Matlab,, modeling- optical ray tracing analysis and thermal modeling of dish type solar collector

    Are you using MATLAB?

    Thank you!



  • Paul Rutland added an answer in Primer Sequences:
    Please I have primer sequences , how can I determine the MW of primer?

    I have primer sequences but Idont have any information about the Molecular weight?

    Paul Rutland

    you could add the bases and multiply the molecular weight of each base by the number of bases but its easier to use online calculators such as oligocalc below . If you have ordered primers the company information sheet almost always has the MW on it somewhere as does the tube that the original primer comes in


  • Irka Hajdas added an answer in Accelerator Mass Spectrometry:
    Which benthic foraminifer is suitable for AMS dating?

    Which benthic foraminifer is suitable for AMS dating?

    Irka Hajdas

    Dear Tina, all foraminifera shells that are younger than  50000 yrs can be dated using C14 method --AMS allows analysis on few mg of benthic shells (any type) can be used for analysis. One of the very first publications is given as an example. 

    best, Irka

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: In this paper the potential of AMS 14C dating of shells handpicked from deep sea sediments is explored. We show that while the age difference between planktonic (surface dwelling) and benthic (bottom dwelling) shells must carry information regarding paleocirculation rates, this message is likely obscured by effects associated with the coupling between bioturbation and dissolution and between bioturbation and abundance change. It is also possible that the 14C/12C ratio in planktonic shells was initially not identical to that in surface water and that the 14C/12C ratio in benthic shells was initially not identical to that in bottom water. These and other biases will plague all attempts to extract the desired information regarding circulation rate changes over the last 20000 years. However in sorting them out, much will be learned about the origin and history of the calcite particles found in deep sea sediments.
      Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms 11/1984; 5(2-5):331-339. DOI:10.1016/0168-583X(84)90538-X
  • Ibrahima Youm added an answer in Surface Chemistry:
    How can I prepare samples for analyzing surface chemistry of nanoparticles using ATR-FTIR?

    I found in literature that FTIR can be used to study the surface chemistry of nanoparticles. Can someone describe in detail how to prepare samples for this measurement?

    Thank you!

    Ibrahima Youm

    For ATR FTIR with powdered sample, you should place the sample on the surface on the crystal. The sample is well packed on the crystal to cover it.

    PS: Make sure the crystal is clean before starting any analysis. 

    I hope this can help

  • Ebot Walter Ojong added an answer in Oxidative Stress:
    What are the best medical laboratory parameters (biochemicals) used in estimating oxidative stress index?

    I intend to estimate serum oxidative stress index using total antioxidant capacity and total plasma peroxidase. I'll welcome reference articles

    Ebot Walter Ojong

    Thanks C. Udenigwe and Samuel Wu.

  • Selina Cheung asked a question in Precognition:
    Any research or theories that support/go against the hypothesis that 'psi' is primarily an unconscious process?

    I'm looking for any research/theory regarding psi (telepathy, clairvoyance, PK & precognition) as an unconscious process... or research/theories that says its a conscious process or states otherwise


    i really appreciate it 

  • Michael Schmitt added an answer in Silica Nanoparticles:
    How to determine the HLB value of nanoparticles functionalized with fatty acids?

    I synthesized silica nanoparticles and functionalized them with fatty acids and I need to know how to obtain the HLB value. I read that i need to prepare different solutions of know HLB value, and if the emulsion is maintained for at least 24h, my nanoparticles have the same HLB value. 

    Is that the way I'm supposed to do it, or is there any other way to determine it?

    Michael Schmitt

    I am not familiar with the hydrophilic-lipophilic balanc for particle dispersions but you have to monitor not not to remove the modification (the particle is an "acid" oxide). I suggest using an alkyl-silane which will result in a covalently linked modification. You may also check the modification by IR as performed within the reference.

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: The migration and transport of polymerization initiators are problematic for commercially used polymerization procedures. For example, UV printing of packaging generates products with potentially harmful components that come in contact with food. Enlarging the size of the initiator is the only way to prevent contamination, e.g., by gas phase transport. In this manuscript, the synthesis and advanced and full analyses of novel nanoparticle-based types of non-migration, fragmenting and non-fragmenting photo-initiators will be presented in detail. This study introduces non-fragmenting/“Norrish type II” and fragmenting/“Norrish type I” ZnO nanoparticle-based initiators and compares them with two commercial products, a “Norrish type I” initiator and a “Norrish type II” initiator. Therefore, inter alia, the recently developed analysis involves examining the solidification by UV-vis and the double bond content by Raman. Irradiation is performed using absolute and spectrally calibrated xenon flash lights. A novel procedure for absolute and spectral calibration of such light sources is also presented. The non-optimized “Norrish type II” particle-based initiator is already many times faster than benzophenone, which is a molecular initiator of the same non-fragmenting type. This experimentally observed difference in reactive particle-based systems without co-initiators is unexpected. Co-initiators are normally an additional molecular species, which leads to migration problems. The discovery of significant initiation potential resulting in a very well-dispersed organic-inorganic hybrid material suggests a new field of research opportunities at the interface of physical chemistry, polymer chemistry and engineering science, with enormous value for human health.
      Nanoscale 04/2015; 7(21). DOI:10.1039/C5NR00850F
  • Witold Orlik added an answer in Alpha:
    Calculating Cronbach alpha in R

    Does anyone know how to calculate the Cronbach alpha in R?

    Witold Orlik

    Hello there, 

    I have never used R so I am not sure if it is helpful, but please see the attached file (page 2) and also video link.

    Best wishes

    + 1 more attachment

  • Ala Bahaaldin asked a question in PEAKS:
    The situation described below were encountered while carrying out EDX in the SEM. Give brief explanations outlining the reasons for each case ?

    The sample analyzed is a Si-Ge alloy thin –film (few 100 nm tick) deposited epitaxially on a Si-substrate. At 20 KeV primary beam energy the Ge K (9.8 KeV) and Ge L( 1.2 KeV) characteristic X- rays are weakly excited, while the Si K (1.7 KeV) is strongly excited. When the primary beam energy was reduced to 5 KeV the Ge K X-rays were no longer detected and the intensity of Ge L increased with respect to Si K X-rays.

    For an Fe-rich alloy the EDX spectrum acquired with a long time constant showed the Fe K X-ray peak at 5.9 keV as well as another peak at 11.8 KeV. When the time constant for acquisition was shortened this second peak virtually disappeared.

    A Mo-containing alloy that had been in long term operation in a sulpher-rich environment was analyzed for  its chemical composition. The Mo concentration calculated using Mo L ( 2.3 KeV) X-rays was consistently higher than that calculated using Mo Kα (17.4 KeV) X –rays even after ZAF corrections were applied.

  • Mokonen Merga Iticha asked a question in Hydro:
    How we perform effect of climate change on hydro logical extremes for a given river basin using only statistical down scaling method?

    How we perform effect of climate change on hydro logical extremes for a given river basin using only statistical down scaling method?

  • Roberto Kasuo Miyake added an answer in Phlebology:
    Is Restless Leg Syndrome (RLS) a disease or just a misdiagnosis of vein insufficiency?

    1- Its said that RLS affects approximately 10% of people in the United States (American College of Phlebology "Healthy Veins Healthy Legs - A Patient's Guide to Phlebology). 

    2- Chronic Venous Disease (CVD) may occur without visible varicosities. Deep vein insufficiency, perforant vein insufficiency and saphenous insufficiency may be misdiagnosed by duplex ultrasound scanning (DUS). False negative are common and a physician without experience with phlebology may receive a negative DUS and conclude that there is no CVD.

    3- But then why would the patient improve symptoms when they start to loose weight, return to do physical activities and use compression stockings?

    4- We've been doing our own DUS since 2003 and the amount of patients that did a DUS and had false negative result is alarming.

    5- Other interesting data we collected in our clinic. We do DUS in 100% of the patients and 33% of the asymptomatic patients have at least one segment of long reflux on the saphenous vein. Clinica Miyake is a private clinic in Brazil devoted 100% fo Phlebology since 1962. More than 90% of the patients have aesthetic concern on the legs).

    6- Why would an asymptomatic patient have a long saphenous reflux and no symptoms? They normally are not overweight, exercise frequently, and have a good quality of life. Then the calf pumping compensate the reflux.

    7- a careful clinical history may detect that an "asymptomatic" patient have heavy legs and/or swelling in a long flight or long standing day. When finally resting the legs, the better circulation may cause symptoms known as RLS.

    8- Vein diagnosis is still improving. A perforant vein with 2mm diameter and no reflux detected by ultrasound may cause pain during palpation and we have seen for many years improvement after proper surgical ligation.

    9- patients with no reflux on the saphenous veins, no painful perforant vein but with telangiectasias and feeder veins may be diagnosed as RLS as well. Augmented Reality (Veinviewer) may help detect the feeder veins. After treating the telangiectasias and feeder veins, we've also seen symptoms such as aching, burning, heaviness and itching disappear after CLaCS treatment.

    + 2 more attachments

    Roberto Kasuo Miyake

    I truly believe that Research Gate will improve medicine Worldwide! Uncountable patients will benefit. Thank you for your clarification Stephen N Smith!

  • Masoud Ovissi added an answer in Mineralogy:
    What would be the best approach for finding the Genesis (Origin) of Copper deposit?


    I am making proposal on Aynak Copper Deposit, Afghanistan. The genesis for Aynak Copper Deposit is proposed as sediment hosted syngenetic deposit but there are some points (have Intrusion which is felsic to mafic in composition, also the source of magma is unknown whether it was fertile or not) which I think is epigenetic hydrothermal deposit.

    I have no idea what would be the possible approach (methodology) to find whether it is Hydrothermal deposit or not. Also mineralogical and geochemical investigation of both mineralized and unmineralized rocks would be helpful for finding the hydrothermal source?

    Best Regards
    Wasiq Lutfi


    Masoud Ovissi

    Dear Wasiq,

    Also you can find some data in attached report of British Geological Survey.

    Hope this file answer some of your questions.

    Best Wishes,

    Masoud Ovissi

  • Ana Nikoli added an answer in Flame Atomic Absorption Spectroscopy :
    Can anyone help with the analysis from determination of potassium in banana by Flame-Atomic Absorption Spectrophotometry?

    Could anyone help me to discuss about this figure. What is purpose ?

    ContrAA 700 AAS


    Nikolic Ana

    Ana Nikoli

    Thank you very much. 

  • Leighton Ellis added an answer in eLearning:
    What are the barriers to effective use of e-learning by academic staff and students?

    My focus is on Engineering Education. 

    Leighton Ellis

    Hi Pedro, 

    Thank you for your comments! 

    My focus is on BSc and MSc Civil Engineering students. At this point its looking at e-Learning in general. 

  • Asif Laldin added an answer in Allozymes:
    What are the Pro's and Con's of using Allozyme eletrophoresis for species assignment and population genetic studies?

    Allozymes were commonly used up to the late 1990s. 

    Aside from being a cheap and easy method to apply what are the other real benefits of using this method for population genetic studies. 

    What are some of the major draw backs?

    If you could direct me towards some literature I would be most grateful. 

    Asif Laldin

    Thank you for such a informative response. Many thanks!!