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  • David Farringdon Spencer added an answer in Plasmids:
    Does anybody know about sequences of plasmid pLG270 ?

    I am trying to insert the yeast YEplac 195 promoter to pLG270 but I can not find the sequence of plasmid.

  • Jasmina Đeđibegović added an answer in Metabolics:
    What is the impact of significantly reduced sodium Ingestion on NIS?

    Suppressed or reduced iodine intake (in humans) has an effect on the efficiency of NIS.  Has anyone studied the effect of reduced sodium intake on NIS in patients?  Thanks.  Hypothesis: Reduced sodium intake may tend to initiate metabolic inefficiency leading to weight gain and perhaps obesity.

    Jasmina Đeđibegović

    NIS stands for the  sodium/iodide symporter on the basement membrane of thyroid follicular cells, where it allows for iodide uptake.

    The system co-transports two  Na+ ions along with one I- ion, with the transmembrane sodium gradient serving as the driving force for iodide uptake. So, it's efficacy depends on sodium gradient on the membrane, which is well controlled in normal physiological state (by Na+/K+-ATPase). It does not seem realistic that somewhat reduced sodium intake would significantly affect the iodine uptake in the thyroid gland (how low exactly you plan to go with this sodium reduction?). At the population level, sodium chloride (salt) is the main iodine source in many regions worldwide, so reduction in iodized salt intake would result in both reduction in sodium and iodine (the iodine reduction being far more relevant in this respect).


  • Sudarson S. Sinha added an answer in FITC:
    Can any one give the protocol for labeling of proteins with rhodamine, FITC and cy3 or cy5 for FRET studies ?

    I want to study protein protein interactions using FRET. So can you give me suggestions regarding which labeling agents are better to use for labeling specific residues of proteins. Which cross linker is easy for the studying of protein-protein interactions?

  • Omar Carlo Gioacchino Gelo added an answer in Adult Attachment:
    What are the main theories and studies about attunement in infants and (especially) in adults?

    I use the word 'attunement', but I am well aware that various terminologies have been employed to indicate almost identical concepts: mirroring, affect mirroring, affect attunement, etc. so all theoretical perspectives are welcome!

    Omar Carlo Gioacchino Gelo

    ...this is very interesting

  • Sarah Ahmad asked a question in Tourism:
    What are the urban tourism in deprived neighbourhoods

    what are the urban tourism in deprived neighbourhoods

  • Girdhar Singh Deora added an answer in Cyclodextrin:
    Can I use Cyclodextrin to improve the solubility of a compound?

    Dear Researchers,

    This is Giri from University of Queensland, Australia. I want to increase the solubility of a chemical compound so, I can use it for animal studies. This compound is water as well as DMSO insoluble. Can you please suggest me whether I can use cyclodextrin to improve the solubility of this compound? If yes, then which is the suitable method for this process?

    Thanks and Regards, Giri

    Girdhar Singh Deora

    Dear Contributors, Thanks a lot for all your suggestions.  

    @Dr Laszlo Jicsinszky-thanks for your detailed explanations about use of cyclodextrin (CDx). I tried HP-CDx to make a complex with my compound.

    @Prof Jasmina Khanam-Thanks for your suggestions. yes, I'm going through literature for the better understanding of this phenomena.

    @Prof Anwar A Hussain-Thanks for your suggestion.

    My apologies as this is a commercial sensitive project so can't share the compound structure.

    a quick query again, is it required to be in solution form for both CDx and compound to form a complex?

    My compound is insoluble in most of the organic solvents except DMF (m.p. 182 degree C). I dissolved both CDx and comp in DMF - then mixed together and added water - it looks a clear solution but still need to analyse by spectroscopic methods to confirm.

    Thanks, Giri

  • Jeffrey La Tourette asked a question in Physical Properties:
    What is a "highly filled material"?

    I sent an inquiry to a polymer company asking if they had a material that satisfied certain requirements with regard to its physical properties. In their response (see below), they used the term "highly filled material".

    "Unfortunately we do not have material fullfill that requirements in terms of impact data...I guess the best fit for your request could be a composite or highly filled material"

    Does anyone know what this term means?

  • Carlos Eduardo Maldonado added an answer in Earth:
    Has anyone worked on how extremophiles process information?

    Extremophiles -bacteria and archaea- are fundamental for the understanding of life on Earth - and most probably beyond the Earth. The knowledge about higher or superior living forms surpasses, by and large, the knowledge we have about extremophiles.

    To be sure, one salient feature of life is that living beings do process information. Whereas much research has been carried out regarding mammals and plants, very little or nothing has been said in respecto to the various extremophiles (acidophilus, etc.).

    I am trying to do some research on this issue. Could you please help me? Thank you very much.

    Carlos Eduardo Maldonado

    Thank you very much dear Artur. I have already found her here on RG... Gonna read about her publications.

  • Mario Fragoso Saavedra added an answer in Cell Culture:
    In cell culture, what does yeast contamination look like?
    I observed a flask of fibroblast cells under the microscope the other day and I noticed lots of globule-like bodies located all around the membranes of many cells. At first I thought they were lipid droplets, but they all seemed to be on the membrane of the cells rather than in the media. Could this be yeast? I've begun treating them with extra amphotericin B. These are the only cell lines we have.
    Mario Fragoso Saavedra

    Does anybody have an image (or at least a description) of fungus-contaminated DMEM media?

  • Michael Sankey added an answer in Andragogy:
    Is there any research out there about heutagogical practices in indigenous contexts?

    Heutagogy, a branch of Andragogy. Hase and Kenyon (2000) first proposed heutagogy as they believe that adult learning is learner led as opposed to teacher led.

    Michael Sankey

    As we know many adult students are internally, or intrinsically motivated, believing that education has a specific purpose, hence motivation them to perform and be willing to sacrifice both time and energy to do well (a key plank of Heutagogy). From the psychological side of the fence this is all tied up with Self Determination Theory (Ryan & Deci, 2000), or SDT, and Social Capitol Theory (Kickett, 2012), or SCT. 

    What we have found with our research with Indigenous Australians is that we need to be looking at and practices associated with identity forming and relatedness, as they apply to learning and teaching. Particularly in our context where students need to also experience this in the formal online environment, but are not necessarily comfortable in these environments that can sometimes be quite depersonalising.

    Not surprisingly, we also found that relatedness is understood in various ways across cultures: for example, in relation to kinship and country in Indigenous contexts (Martin, 2003), through social capital theory (Coleman, 1988), and in online environments through networked learning (Goodyear, Jones, Asensio, Hodgson, & Steeples, 2005) and connectivism (Siemens, 2004).

    However, relatedness in this context refers to the trust and reciprocity that is developed in bonding, binding and linking relationships (Woolcock & Narayan, 2000) between people, mediated inside and outside of virtual learning environments, and designed to affirm cultural and racial identity and practices. The conceptual location where these ideas and practices are negotiated and reframed is what Nakata calls the “cultural interface” (Nakata, 2007). 

    Our experience Australian indigenous students indicates that online learning spaces are not generally conducive to the sorts of relatedness upon which their lives depend. Also, representation of identity within the online environment is an essential prerequisite for establishing connections. However, opportunities to develop an online identity within our units/courses are at best ‘ad hoc’ and the extent to which students are prepared to reveal their identities depends on a range of factors including the extent to which others in the environment are ‘known’.

    The yearning for connection in online learning environments contrasts with the sense some students have of this environment is a ‘formal’ environment, rather than a ‘social’ one, and where the mechanisms for making connections (such as online discussion forums) are not designed in ways that can draw Indigenous students into the learning environment, or seen to be connected with other parts of their lives.

    Importantly, from a design perspective, many learning design models that guide the development of online learning spaces and learning interactions have very little focus on ‘relationship’ focusing more on ‘connectedness’ around a concept, and where this does exist, it is mainly in the context of teacher-student processes and interactions around a learning scenario, rather than around identity.

    The points presented below highlight the social aspects of learning and the need for an institutional level approach to support holistic learning environments.  It can be as simple as incorporating some concepts by which relatedness is achieved, particularly for Indigenous students, or it could be extended to incorporate other systems within the VLE that are aligned with the LMS such as an ePortfolio, an internal social networking tool, or/and allowing for the syndication of information from certain social media sites. Regardless of how it is conceived the following recommendations came out of our research:

    At an Institutional level:

    • Engagement with a suite of technologies to facilitate the development of comprehensive student and staff profiles (identity), along with a openness to receive external social networking feeds.
    • Train staff in the notion of digital and social networking literacy and on how to facilitate student engagement, based on a centralized profile (identity). 
    • Establish and support specific online spaces for Indigenous students (and other defined groups), within the institutional community site, to facilitate the networking across the institution.

    At a Unit level:

    • Ensure the design of unit environments can facilitate the use of, and align with, student profiles. 
    • Train and support students, early in their engagement with the institution, on how to represent themselves in their university based profile (identity). This requires a level of sophistication and may, for example, address ways to encode Indigeneity that may not be visible to non-Indigenous students or staff, if this is desired.

    These recommendations provide a means to integrate concepts and practices aligned with ‘relatedness’ into HE institutions, to create friendlier and safer online spaces for Indigenous, and indeed for all students, in order to enhance the experience of online learning.

    I'm happy to supply the references separately, to save space here. However, the pear this research is based on will be published next week and i can forward you the link, once live.



    Associate Professor Michael Sankey
    Learning Environments and Media
    University of Southern Queensland, Australia

    Alison Reedy (First Author)
    Office of Learning and Teaching
    Charles Darwin University, Australia

  • George Stoica added an answer in Scopus:
    When is the time to Withdraw a Manuscript in a "Decent" Journal?

    Dear Colleagues

    I want to hear opinions regard the issue of long peer-review processes of journals that are considered good (indexed in SCI/Scopus/Medline). Recently I had to withdraw a manuscript from "Public Health", which spent more than 6 months in peer-review, until we decided to withdraw it.

    Is there any time limit currently recommended to do this. Was 6 months too much?

    Thanks for your comments.

    George Stoica

    Dear Alfonso,

    I had such an experience with the Journal of Mathematical Economics and my paper "Relevant coherent measures of risk"; if you go to my RG webpage, you can see that, between the "received date" and "accepted date" there are almost 3 years! I was patient with them, because this journal is the right place for my paper, but this was my first and last paper submitted to that journal.

    Sincerely, George

  • Hayk L. Khachatryan added an answer in Electrodeposition:
    Why has Fe diffused from substrate to the Co-W coating after heating at 600 °C for 4 hours? Why is Fe higher on top of coating than in the coating?

    I produce Co-W alloy coating on mild steel from electrodeposited and then the coating was heated in vaccum at 600 °C for 4 hr.The EDS of cross section of coating shows that the concentration of Fe is very higher on the top of coating than in the coating!!i dont know what happened. please help meCo-

    Hayk L. Khachatryan

    Diffusion of Fe-ion in the pure Co (single crystal) is very low, e.g. at 808oC it measured to be D=7.2*10^-14 (cm2/s). So, Dr. Verlotski observed correctly, in the lower temperature diffusion would be negligible and not measurable. However the grain boundaries may promote diffusion and it can be calculated by equation manifested in the article (please refer to link).


  • Dr Haider Al-Ani added an answer in Geotechnics:
    Wha are the possible research topics if somebody wants to work with expensive soil???

    I am doing Msc in geotechnical engineering.i want to work on expansive soils please give me some ideas how to proceed in this topic as alot of work has already been done on expansive soil.please give me some suggestion.i am confused in selecting my msc research topic.


  • Leonard Oremont added an answer in Abaqus:
    Is surface or general contact suitable for studying stresses using the finite element method?

    Hi everyone

    I'm doing FE simulation for Press-braking operation in 3D. I want to study the stresses through the thickness of the plate. I use shell element.

    However, the case of applying surface or general contact is still not clear to me. So, could anyone tell me which one is suitable for my simulation? and how to apply it?

    Thank you in advance.....

    Leonard Oremont

     Yes, though as usual you will have to model the problem well.  Contact between two deformable bodies as done for example in Abaqus ends up calculating the forces between the two meshes in contact at the node levels so that they are in static or dynamic equilibrium -depending on the analysis type selected; therefore, in the end, you may think of these forces as loads on the individual parts,  and the resulting strain & stress fields may be used for your purpose.  On your problem, friction is very important and regrettably contact is much more difficult to resolve when friction is involved, yet doable.

  • David Farringdon Spencer added an answer in PCR:
    Could any one give some advise on amplifying DNA extracted from paraffin embedded tissue?

    I have added DTT to the extraction buffer, and or I have boiled DNA prior the PCR reaction,  I have also used kits and no-kits for the extraction but the PCR results are still poor.

  • Sanat Kumar Mishra asked a question in Transmission Line:
    How does the transmission line parameters vary with cable length?


    While modelling a transmission line, I have considered L',R',C',G' are the inductance per unit length, resistance per unit length, capacitance per unit length and conductance per unit length respectively.

    However, I don't know how does these parameters vary if the length of the transmission line is increased (say doubled).

    Kindly clarify.

    Thank you.

  • Hassan Sheikh added an answer in Nanoindentation:
    How can obtain the Elastic modulus for unknown material by nano indentation?

    The Elastic modulus E can be obtain by this equation, (1/Er)= (1-V2)/E + (1-Vi2)/Ei Here,Vi and Ei are Poisson's  ratio and modulus of Elasticity for the indenter. V and E are the Poisson's ratio and modulus of Elasticity for tested material. By the above equation for known material V and Ei ,Vi ,Er we can easily determine the Elastic modulus of the material. However for the unknown material if the Poisson's ratio is unknown then how can i get modulus of elasticity for that materials.

    Hassan Sheikh


    Please read these references

    [1] J. Hay, “Introduction to Instrumented Indentation Testing”, Nanomechanical Characterization of Materials by Nanoindentation Series: EXPERIMENTAL TECHNIQUES, pp. 66-72, 2009.

    [2] J. Ramirez, “Nanoindentation Fracture Toughness”, NANOVEA, 2010.

  • Ahmad Zafari added an answer in Annealing:
    How is the grain growth exponent found?

    Hi All, 

    The following equation is suggested to estimate grain size changes due to grain growth during annealing

    Dn - D0n=K(t-t0)

    I have seen in many papers that the n is obtained by plotting ln(D-D0) vs ln(t-t0), but isn't this wrong?? How can the equation above be rewritten as 


    This is correct only if D0 is much smaller than D, so Dn -Don ~ Dn

    But, if Do is not that small compared to D, how "n" is calculated??

    I would be grateful if you would clarify this issue for me. 

    Thanks in advance for helping. 

    Ahmad Zafari

    Thanks everyone for your helpful comments

    Dear Mourik, 

    Would you please explain what physical considerations are required? it was mentioned in one of the papers Bhaskaran posted here that D-D0 is equal to kt1/n (i.e. D-D0=kt1/n) simply because there is a linear relationship between ln(D-D0) and lnt.

    One more question. According to my data, plotting ln(D-D0) vs lnt resulted in n = 2, but the K value I found from D-D0=kt0.5 was different from D2 - D02=K(t-t0), why is that? if these two equations are approximately equal, there should not  be a big difference between K values obtained from them.

  • Jaime Pinzon added an answer in Vascular Biology:
    What computer program should I use to compare plant communities?

    I'm doing an inventory of vascular plants in a piedmont gorge (USA) and I'm going to do some transects for community comparisons and analysis. I'll compare communities on different facing slopes and of different elevations. I hear R is the go-to program but are there any other tools I should consider?

    Jaime Pinzon

    Yes, R has very powerful tools that will allow you perform multivariate analyses, biodiversity analyses, etc. There are several packages that will help you to answer these types of questions, for instance, vegan and labdsv have many functions for common community-level analyses, indicspecies for analyses of indicator species, vegetarian for diversity analyses, iNEXT for rarefaction, etc...I guess it'll depend on your research questions and hypothesis that you can choose what types of analyses you can carry out. Beware that R is not very friendly, you need to know about programming and the learning curve is somewhat steep; however, if you learn R language, you can perform pretty much anything you wish. You move away from windows-based software where you click, click and get an output but you'll have absolute control of what you are doing. I suggest you to read Brocard et al. 2011. Numercial Ecology with R. Springer, for an excellent introduction about R and multivariate analyses.

  • Ted Swift added an answer in Statistical Testing:
    What does that mean when my time series data have serial correlation? Can I proceed to next test or stage?

    I have run serial correlation test using Ljung-box Q statistics, and the results show that my data has serial correlation. Can it effect my data and is there any problem if I proceed to next regression?

    Ted Swift

    ARIMA  means Autoregressive integrated moving average. An "ARIMA model" approach enables you to examine the model's residuals, actually quantify the serial correlation (if any), and correct for it in test statistics. If the proper textbook isn't handy, a Google search on "ARIMA model" or "ARIMA residuals", in association with your favorite analysis software, will help get you on the right track. Different software will implement ARIMA models differently, of course. It sounds like the software you're using is at least conscious of the existence of autocorrelation. Andrey makes a good point: "Real world" data are only rarely well-behaved, and violating the normality assumption will also throw off validity of statistical tests that assume or require normality. This is less of a problem if you are using nonparametric tests, but still a good idea to stay alert.

  • Attila Haris added an answer in Entomology:
    Anybody has these works in his institution's library?

    Anybody has this works in his institution library? and could he check or photocopy only few pages for me? (if yes, I will provide data).Please help.

    FRENZEL S F Dissertatio de insectis Hungariae cum nive delapsis Wittenberg, 1673

    DAN. GUIL. MOLLERUS : Meditatio de insectis quibusdam Hungaricis prodigiosis, anno proxime praeterito ex aere una cum nive in agros delapsis (Franco-furti ad Moenum) 1673

    Waiting for your help

    Attila Haris

    Dear Matthew and Mark,

    "he librarian does locate, scan and e-mail specific pages on request."

    This is the problem...

    If you don't know this work, (as I don't), .generally librarian are not able to select one or 2 pages to scan  which I really need. But a research entomologist from a museum simply could check the  book and could decide within few minutes and could answer: "hi Attila, I checked these works and in the first book there is nothing  you really need  but in the other  book  i found 2 pages you need for your research...."  

    So, I can not expect that librarian chechk these work for me neither want him/her to scan the whole book only to check and decide wether the book is relevant for me or not :))

  • Michael R. Hughes asked a question in Wrist Joint:
    Does anybody have a reliable (reproducible) method for flushing synovial fluid from mouse ankel joints?

    I'm trying to do flow cytometric analysis of the inflammatory cell infiltrate in the arthritic joints in mice.  I've been targeting the ankle and "wrist" joints. I've tried to wing it (flushing with 1 mL PBS/2 mM EDTA/10% FBS using a 25G needle) but the variability from mouse to mouse is very high.  I haven't found an article that describes the precise methodology for flushing the joints for flow or cytokine analysis. Does anyone have a protocol they trust?

    With thanks,


  • Lior Kornblum added an answer in Pt Nanoparticles:
    Can anyone tell me why attachment of Pt nanoparticles on TiO2 shows metallic behavior when record temperature dependent electrical characteristics?

    In case of TiO2, behavior is semiconducting, but in case of TiO2/Pt, it become metallic.  

    Lior Kornblum

    How were the particles "attached" ? What is the geometry? Do you have any structural information such as HRSEM? What's the nominal nanoparticle density? What's the magnitude of the room temperature sheet resistance?

    A possible explanation would be that the nanoparticles are so dense that their conductivity percolates; this would be characterized by a very low resistivity and it could be easily proved/disproved with structural analysis.

    Alternatively, if the "attachment" process involves high temperatures, or plasma, you may have introduced defects into the TiO2, which could sometimes act as dopants and possibly exhibit metal-like behavior at some conditions, as suggested in the previous comment.

  • Thaer Al-Jadir added an answer in Metal Organic Frameworks:
    Is it possible that the amount adsorbed of carbon dioxide in MOFs for experimental measurements are significantly higher than the simulations?

    Sometimes, the amount adsorbed of polar gas such as carbon dioxide in MOFs for the experimental measurements are significantly higher than the simulations, Do you know why?  Note that the MOF in this case is not open metal.

    Thaer Al-Jadir

    Thanks Jonas Nyman for your answer. However, can you please explain more how the force fields with multipole electrostatics and the adsorption free energy would give more accurate results?

  • Manohar Sehgal added an answer in Heusler Alloys:
    How do I calculate the moment to half and full Heusler alloys in the slater Pauling rule?

    Please expalin with example

    Manohar Sehgal

     [i] It is the same - the one   reported in the literature as well as by your self:

         Mt = Zt − 18

    [a] The last column  gives Mt , the magnetic moment in BM[ Bohr Magneton]

    [b] The second last column represents 18.

    [c]The third last represents Zt.

    [d] Then comes the number of   valence  electrons in Sb[ 5s^2 5p^3], Mn[ 3d^5 4s^2] and in the  other transition metal:Ni, Pd, Pt, Co, Rh, Ir and Fe.

    [e] Ni, Pd,Pt – being  congeners well have the same  number of valence electrons(10) in nd. ns subshells

    [f] Co, Rh,Ir – being  congeners well have the same  number of  electrons(9) in nd. ns subshells.

     [g] Fe , as you know, is 3d^64s^2—there are 8 electrons.

    {2} I will appreciate  if you  compare these values with the ones reported in the literature.

    [3] I , humbly, wait for your  observations. Thks.

  • Rafik Karaman added an answer in Cephalexin:
    Is anybody interested in conducting in vivo kinetics studies (pharmacokinetics) for novel amoxicillin and cephalexin prodrugs?

    We have designed and synthesized a number of novel amoxicillin and cephalexin prodrugs and looking for somebody to carry out the in vivo studies for determining their pharmacokinetics parameters.

    Rafik Karaman

    Dear Anwar,

    Their bitter taste when administered in liquid preparation for pediatrics and geriatrics.


  • Ashutosh Dharap added an answer in microRNA:
    Is it better ti use triazole or total RNA or miRNA isolation kit to isolate miRNA (less than 200 nt) from serum or plasma?

    i want to know which method is suitable  to extract miRNA from serum or plasma use triazole or total RNA column spin or miRNA column spin isolation kit .

    many studies used the first first and the second and some used the third. i want th e more suitable as iam afraid because miRNA is small (less than 200 nt). iam not sure if the first and the second can isolate it . the third is expensive

    Ashutosh Dharap

    I have had consistently excellent results with the mirVana miRNA isolation kit (using cultured cells or tissues). It isolates total RNA, but has an optional step to enrich for small RNAs. The yield is very good.

  • Miquel À. Capó-Juan added an answer in Sport Psychology:
    What are the most common tests to measure the motivation for sport in disability?

    I think that  I could use:

    • Physical Activity and Disability Survey (PADS) (Rimmer et al., 1999)
    • BREQ-2 (Markland & Tobbin, 2004)

    Do you Know a better test?

    Miquel À. Capó-Juan


    First of all, thank you for your answer. Secondly, could you send me the questionnaire or tell me the author and their year of publication?
    Is this questionnaire validated in spanish language?

    Thank you.


  • Mahanadou Tembely added an answer in Markov Chains:
    Does somebody knows how to get the state transition probability matrix(Markov Chain) from the data of 1D and 2D random rough generated?

    Hello everybody, I generated a 1D and 2D random rough surface. I need to analyse these rough surface using Markov Chain.

    Mahanadou Tembely

    thank again for you quick answer.

    What you are saying make sens.It more applicable for discrete transition.

    I discretized  the surface generated using Matlab and from that I  need to get the state transition probability matrix(Markov Chain). Do you know a algorithm  to get this.