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  • Bob Loynes added an answer in Egyptology:
    Are these 2 black areas in the orbit pathologies or are they normal?
    I'm researching mummies and I am trying to find pathologies for my study. I am not sure whether it is the angle of the x ray causing these 2 circles in the orbit or whether it is an anomaly.
    Bob Loynes · The University of Manchester

    I agree with all the above answers.  These foramina are normal anatomy.

    Having CT scanned 8 of the mummies in the Liverpool Museum, I'm interested to know which mummy this is.  There also seem to be significant abnormalities in the rib cage.

    Feel free to contact me through my Manchester email address.


  • Humphrey Lumadede Mudoga asked a question in Lignin:
    Measurement of LIGNIN

    How do I go About to measure amount Lignin in bagasse or other materials


  • Pushpendra Singh added an answer in Graphene:
    Please explain this paragraph related to graphene

    Graphene is composed of sp2-bonded carbon atoms arranged
    in a two-dimensional honeycomb lattice.
    The lattice can be seen as consisting of two interpenetrated
    triangular sub-lattices, for which the atoms of one sub-lattice
    are at the center of the triangles defined by the other with a
    carbon-to-carbon inter-atomic length, a(C–C), of 1.42A°
    . The unit
    cell comprises two carbon atoms and is invariant under a
    rotation of 120 degree around any atom. Each atom has one s orbital
    and two in-plane p orbitals contributing to the mechanical
    stability of the carbon sheet. 

    how they contribute mechanical properties, 

    Pushpendra Singh · Indian Institute of Technology Roorkee

    thanks Mr. Kien-Cuong Pham for your answer, it helped me good

  • How many lags are to be taken for valuing the granger causality test?

    She is doing research on  cross listed stocks ( ADRs , GDRs) for valuation purpose she is using granger causality test through E views software, to compare the companies local and international stock market price. For that she need suggestion, of how many lags to be taken into consideration for the above test,

    Philippe de Peretti · Université de Paris 1 Panthéon-Sorbonne


    I guess a two-step methodology should be used. Using a level VAR, try a lot of lags, and keep only those having spherical distrubances (Normal, no ARCH, no Autocorrelations....). Then among all this models, choose the one having the minimal AIC, or better the minimal AICc. Please note that using the AIC alone does not guaranty that residuals are correct, hence the two-step approach.



  • Paweł P Łabaj added an answer in Microarray:
    Software for cross-platform microarray results comparison


    I am looking for a software allowing the user to compare the results of microarray experiments, but taking into account different platforms. I mean to compare results from i.e. Agilent and Affymetrix arrays.

    I have found MicroarrayRUs, but it supports only Affymetrix, and Illumina. 

    I will be grateful for any suggestions. 

    Paweł P Łabaj · University of Natural Resources and Life Science Vienna

    Comparison of different (microarray) platforms is a goal of the MAQC/SEQC consortium:


    In 2006 a special issue of Nature Biotechnology was released containing set of publications dedicated to this topic:


    You will not find there any software but rather description of metrics which could be used for a such comparison (more less as described by Michael).

    Extension of this to RNA-Seq has just been published by the way:


  • Antonio Ariza added an answer in Imidazoles:
    Why the protein moves Zig Zag way in the SDS-PAGE?

    I have loaded protein sample eluted from Ni-NTA column with different concentration of imidazole. I have found that the migration of of protein sample in 12% SDS-PAGE is not smooth or in a straight line. It is running in zig zag direction! why is it so? Is it because of excess charge present in the sample due to presence of imidazole and salts during purification process? How should I avoid it?

    Antonio Ariza · University of Oxford

    I have never had problems with high salt or imidazole myself and my samples usually range from 0 to 0.5 M imidazole with 500 mM NaCl. I have even run samples with 2 M NaCl + 1.5 M NaBr on gels (but these didn't have imidazole in them) and they tended to look a little bit smeary compared to the low salt samples, but other than that they were fine (definitely no zig zags in my experience).

    My guess is that your samples might not have been sufficiently denatured (incorrect loading buffer composition or not heated for long enough), which can also get worse if there was no DTT in your loading buffer. If some of your proteins oligomerise and there is no reducing agent and proper denaturation, then they'll form multimers, partial multimers and aggregates that will give you extra, unexpected bands and smears. Even if your protein of interest doesn't need reducing to run as a monomer on an SDS PAGE gel, there are other proteins that co-elute with your protein in some of the washes and these might need reducing so as not to spoil the gel. So always add fresh DTT to you samples after you add the loading dye (I don't tend to add DTT to my stock of loading buffer as I keep it at room temperature and the DTT would go off after a few days) and then heat for at least 5 minutes (some commercial buffers only need 3 minutes and the samples look worse if you heat them for too long, so read the manufacturers instructions).

    BTW, I would love to see a picture of that zig zag gel, if possible. :o)

  • Rekha Mittal asked a question in Solar Cells:
    How PbS nanoparticles in CdSe matrix leads to better absorption in solar cell?

    How solid solution of CdSe/PbS leads to optimum band gap?

  • Semantic Web

    there are several .rdf data sets. need to find their schema file
    (.owl). (.owl files are necessary for ontology alignment.)
    Do you know any tool which is to extract .owl file from RDF data set?

  • N. Venkatathri added an answer in Titanium:
    Has anyone used Titanium(IV) methoxide as a metal precursor?

    Or are the methoxides unlikely to be substituted?

    N. Venkatathri · National Institute of Technology, Warangal

    You have to specify, why do you want to use methoxide, why not isopropoxide.  We have used the latter one many times.  It is highly unstable.  If you keep at atmospheric air for more than specified time it will give respective oxides.

  • Mondeli Mngoma asked a question in Color:
    Natural Product Decomposition

    My mid-polar to polar fractions have decomposed from a golden-brown colour to green, blue, violet and black colours, but I can still see the separation of compounds via TLC profiling. What could this be caused by, and what does it show? Help please

  • Annamalai Nathan added an answer in Chlorophyll a:
    Whether chlorophyll traits are good for measuring drought tolerance ? If so which one is best among them in field for large populations ?

    So does anyone know among various chlorophyll traits (Chlorophyll A, Chlorophyll B, Total Chlorophyll and Chlorophyll A/B ratio), is there any one best trait that can be used for measuring drought or heat 

    Annamalai Nathan · Rubber Research Institute of India

    Chlorophyll fluorescence parameter, especially,  Phi PS II (light exposed quantum yield of PSII) is a  relevant parameter for the assessment of drought tolerant potential in many crops. Pulse amplitude modulated fluorescence (PAM) system is widely used for this measurement. Chlorophyll content/index  meter is a rapid system just to know the chlorophyll content or rate of photobleaching. Drought is little bit complex phenomena setting in field when cocomittant occurence of soil water deficit, high solar light, high temperature  and atmospheric VPD increase. Chlorophyll bleaching may  just occur due to high temperature or high light condition alone also, therefore, chlorophyll index  may not be considered for assessing the drought tolerence potential of any crop.

    Annamalai Nathan

  • Marianna Gardener added an answer in Actigraphy:
    What is the best method to understand sleep actigraphy in older people?

    I have completed a study with older adults in care homes monitoring sleep and light patterns using actigraphy. I have a mixed set of outputs - some with a regular sleep cycle and others more disrupted patterns. I'm trying to best understand sleep quality and the most relevant variables to extract from the software (Philips respironic actiwatch spectrum). I'm not sure if setting a custom interval would help best or if the pattern shown should determine how to look at the stats. Any thoughts of good references welcomed.

    Marianna Gardener · University of Portsmouth

    The attached study by van Dijk et al., (2012) may help shed some light.

  • How do public sector reforms help democratize the public sector governance?

    It seems to me that public sector reforms for last 30 years, or so, have been heavily inspired with the theories of economics. From design to evaluation, economics has influenced the study and practice of reforms. Aren't there non-economic aspects of reforms?

    On the other hand, democratization is obviously studied in political terms. Theories of democracies, mostly under representative, participatory and deliberative root, have been the coverage within the study of democratization. Aren't there other approaches (non-political) to study democratization?

    At any stage, it is possible to link the outcome of public sector reforms with the outputs of democracy. This drives me to ask: how do public sector reforms help democratize the public sector governance?

    John Richard Parkinson · The University of Warwick

    Thaneshwar, there's a big literature on the tensions between public administration / management and democracy, and the tensions within various reform movements. Deliberative democracy has been taken as one response to those tensions - check out my 2004 article in Public Administration for a quick outline of some of the issues; the bibliography will help too. Otherwise check out the work of Frank Fischer, Maarten Hajer, the more policy-oriented work of John Dryzek, Yannis Papadopoulos (excellent recent book), Rod Rhodes on the 'hollowing out' thesis... the list could go on. Other resources would be the Poltical Studies Association's Public Administration specialist group; and the annual Interpretive Policy Analysis conferences. 

  • George Asimellis added an answer in Anisocoria:
    How common is anisocoria post lasik? Is it due to suction?

    Anisocoria post lasik

    George Asimellis · LaserVision.gr

    is there any publication supporting this connection between severing corneal nerves and impact on pupilary reflex abnormalities?

  • Ahmed Ali added an answer in Species Specificity:

    I have a case of Rabdomyosarcoma (RMS) in a neonatal goat. I would like to do a confirmatory diagnosis using immunohistochemistry (IHC). My question is, whether IHT is species specific?. Can anybody help me?

    Ahmed Ali · Qassim University

    Thank you very much Dr Ivan for your important information, I may return for you again when I start with the protocol.


  • Ebrahim Osdaghi added an answer in Pathogens:
    Opportunistic Pathogen

    On what basis do we characterize a bacteria as an "Opportunistic Pathogen"?

    Ebrahim Osdaghi · Shiraz University

    Dear Gaurav

    The microorganisms which are not pathogenic on the healthy host in the natural conditions but are invasive and pathogenic on the host when it (the host) is in the unnatural conditions or was weakened by another pathogens are called as the opportunistic pathogens.

  • Markus J. Kögel added an answer in Polytopes:
    Is there some one working on the vertex enumeration algorithm or has Matlab program to enumerate vertices please?

    I need to enumerate all vertices of a over determined LP system and find the vertices of central polytope.

  • Mariana Ilieva added an answer in Zno Thin Films:
    Why does grain size decrease with thickness for ZnO thin films?

    Generally grain size increases with increased film thickness but it is decreasing in my case. What could be the probable reason for this?

    Mariana Ilieva · University of Ruse Angel Kanchev

    Dear Sharma, in order to answer your question, you must specify at least: 1. deposition method; 2. deposition conditions; 3. how do you achieve different coatings thickness.

  • How can I find university staff who are working on fish parasites?

    I'm searching someone who are working on Anisakid larvae in Melbourne.

    Olivera Bjelić-Čabrilo · University of Novi Sad

    You can contact professor dr Vera Nikolic on the Faculty of Biology, University of Belgrade. She work on fish parasite. Her e-mail adress is: vera@bio.bg.ac.rs

  • Bogdan Druga added an answer in Cyanobacteria:
    Can cyanobacteria grow on agar plates without carbon source?

    My cyanobacteria don't grow when I inoculate them to the agar plates from liquid medium. The difference between liquid medium and solid medium is only the presence of agar. Both liquid medium and solid medium are without carbon source. Even I inoculate many cells on agar plates, they turn white after several days. I am confused by this problem...

    Bogdan Druga · Institute of Biological Research

    Mine is a Synechococcus. Many cyanobacteria grow different on agar than on liquid media. For instance, Synechocystis PCC 6803 needs Difco Bacto Agar, but also sodium thiosulfate (about 3 gr / L) to be added for the solid medium. This could be another thing to keep in mind if your Anabaena will not grow well.

  • Raju Murugan added an answer in Aeroacoustics:
    How do I choose the time step for unsteady simulation especially for aeroacoustics related problems?

    I am planning to simulate the aeroacoustic simulation in fluent, to predict the acoustics terms like frequency , how to choose the time step size , because the unsteady problem is based on the timestep size. For closed pipes what kind of acoustics model is suitable.

    Raju Murugan · Indian Institute of Technology Hyderabad

    thank you Yoichi ando and Filippo Maria denaro

  • Samaresh Bera added an answer in Smart Grid:
    Making diverse in consumers demand helps reducing the maximum demand and alleviating overloads, but to what extent is demand diversifying possible?
    Since usually there is one extreme load peak, bearing in mind that a definite quantity of energy (MWh) is going to the consumers what ever the load curve shape is. To what extent is it possible to reshape the daily, monthly, and yearly load curve?
    Samaresh Bera · IIT Kharagpur

    Shiftable appliances can be scheduled to off-peak hours (lower price) to reduce energy consumption cost. I would suggest to read the following paper:

    M Erol-Kantarci, HT Mouftah, "Wireless Sensor Networks for Cost-Efficient Residential Energy Management in the Smart Grid", IEEE Transactions on Smart Grid, 2011.

  • Louxiang Wang added an answer in Sebum:
    How can I make an emulsifier without absorption in IR range (sebum-water mixture)?

    I would like to mix sebum lipids (triglycerides, fatty acids, squalene) and water. Does anyone know suitable emulsifiers that do not have absorption in the IR range (1700-1800 nm)?

    Thank you. Kind regards, Lutz

    Louxiang Wang · University of Alberta

    Nanoparticles are recommonded!

    Good luck

  • Isaac Tuffour added an answer in RNA Interference:
    Can Glutathione S-transferase down regulation cause mortality in hemipteran insects?
    RNA-induced silencing causing mortality of leaf hoppers.
    Isaac Tuffour · Noguchi Memorial Institute for Medical Research

    Generally Glutathione-S-Transferases (GSTs) are enzymes that catalyzes the conjugation of glutathione needed to mop up free radicals and Reactive oxygen species (ROS) generated as a  results of metabolism and other external factors. These ROS are damaging to several biological tissues. GSTs are also essential phase II drug metabolizing enzymes. Recent studies have shown that certain cancers and insects (e.g mosquitoes) have exploited overexpression of GSTs as resistant strategy towards therapeutic agents so as to enhance their survival.

    Over expressed GSTs contribute to insect and cancer resistance and survival in two ways:

    1. Increased levels of GSTs helps mop up reactive oxygen species that are produced as  a result of high metabolic activities thus protecting biological tissues from damage and enhancing survival.

    2.Insects and some cancers with overexpressed GST levels quickly metabolize therapeutic drugs intended for their destruction, into pharmacologically inactive forms thus leading to therapeutic failure.

    In the light of this most recent drugs are designed to either inhibit GST activity or down regulate GST expression so as to reduce resistance and enhance mortality of these cancers and insects

  • Hongyan Ma added an answer in Salts:
    Applying scope of corrosion inhibitors in steel-reinforced concrete

    As I know, NO2- salts and phosphate salts can be used as steel corrosion inhibitors in steel-reinforced concrete structures. I am not very clear about their effect mechanisms. Could anyone recommend references for their effect mechanisms? In addition, they are effective for inhibiting steel corrosion induced by chloride, but are they also effective for inhibiting corrosion induced by low PH value, e.g. carbonation?

    Hongyan Ma · The Hong Kong University of Science and Technology

    Dear Dr. Depentori, Thank you very much for your explanation and comments...

  • Suman Bhullar asked a question in Distributed Systems:
    Radial distribution system

    can we draw a simulink model of radial distribution system? i haven't seen any paper containing simulink model of radial distribution system  except some software .e.g. ETAP.

  • David Becker added an answer in Portraits:
    Documenting the red hair gene?
    I want to document the red hair gene using photography as a visual reference. Can anyone help with information on genetics, rarity and global distribution of this gene?
    David Becker · Technische Universität Chemnitz

    Hello Nadine Wood,

    because I'm also a bit interested in this topic, I have to offer some sources that might be relevant for you. Most of them are about genetic factors, global distribution and behavioral associations. Best wishes, DB.

    Andresen, T., Lunden, D., Drewes, A. M. & Arendt-Nielsen, L. (2011). Pain sensitivity and experimentally induced sensitisation in red haired females. Scandinavian Journal of Pain, 2, 3-6. doi:10.1016/j.sjpain.2010.08.005

    Binkley, C. J., Beacham, A., Neace, W., Gregg, R. G., Liem, E. B. & Sessler, D. I. (2009). Genetic variations associated with red hair color and fear of dental pain, anxiety regarding dental care and avoidance of dental care. Journal of the American Dental Assoiation, 140, 896-905.

    Frost, P. (2006). European hair and eye color. A case of frequency-dependent sexual selection? Evolution and Human Behavior, 27, 85-103. doi:10.1016/j.evolhumbehav.2005.07.002

    Little, A. C., Penton-Voak, I. S., Burt, D. M. & Perrett, D. I. (2003). Investigating an imprinting-like phenomenon in humans Partners and opposite-sex parents have similar hair and eye colour. Evolution and Human Behavior, 24, 43-51.

    Mengel-Jørgensen, J., Eiberg, H., Børsting, C. & Morling, N. (2006). Genetic screening of 15 SNPs in the MC1R gene in relation to hair colour in Danes. International Congress Series, 1288, 55-57.

    Sulem, P., Gudbjartsson, D. F., Stacey, S. N., Helgason, A., Rafnar, T., Magnusson, K. P., Manolescu, A., Karason, A., Palsson, A., Thorleifsson, G., Jakobsdottir, M., Steinberg, S., Pálsson, S., Jonasson, F., Sigurgeirsson, B., Thorisdottir, K., Ragnarsson, R., Benediktsdottir, K. R., Aben, K. K., Kiemeney, L. A., Olafsson, J. H., Gulcher, J., Kong, A. 1, Thorsteinsdottir, U. & Stefansson, K. (2007). Genetic determinants of hair, eye and skin pigmentation in Europeans. Nature Genetics, 39, 1443-1452. doi:10.1038/ng.2007.13

    Walsh, S., Liu, F., Wollstein, A., Kovatsi, L., Ralf, A., Kosiniak-Kamysz, A., Branicki, W. & Kayser, M. (2013). The HIrisPlex system for simultaneous prediction of hair and eye colour from DNA. Forensic Science International: Genetics, 7, 98-115.  http://dx.doi.org/10.1016/j.fsigen.2012.07.005

  • Ashish Patidar added an answer in Hemodialysis:
    What is best protein target for confirming an osteoblastic and osteoclastic phenotype ?
    Is one protein for each activity enough?
    Ashish Patidar · University of Hertfordshire

    Thanks Vivekanand for your reply. 

    I am looking markers for both formation and resoprtion and also for chondrogenic phenotype only. I understand that Bone Specific ALP is for bone formation. Any markers that will be expressed in in vitro cultured cells such Runx-2/cbfa-1, smad, BMPs etc will be great that could be detected with western blotting or Elisa.

    Thanks Again.