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  • Paul C. Lyons asked a question in Sequencing:
    What kind of a shell fauna would you expect if the red clystone came from a freshwater lake in the Middle Pennsylvanian of eastern North America?

    The basic sequence is  repeating sequence of cobble conglomerate, coarse-grain arkosic dark gray sandstone with planar cross-bedding  that is topped a clay drape with ichnofossils (nsects mainly), and red claystone with  scarce terrestrial Middle Pennsylvanian plant megafossils.

  • Mohamed El Naschie added an answer in Differential Geometry:
    If scalar curvature of a manifold is greater than zero, can we say that Ricci curvature is greater than zero ?

    If scalar Curvature of a manifold is greater than zero, can we say that ricci curvature is greater than zero ?

    Mohamed El Naschie


  • Abdul Ghafoor added an answer in Chemical Analysis:
    Are there any correlation between nitrogen, potassium and phosphate concentration in plant tissue?

    I want to estimate the concentration of potassium and phosphate in plant tissue with non destructive method or using nitrogen content as base of independent variabel in mathematic modeling so I don't need to used chemical analysis.

    Abdul Ghafoor

    N and P definitely have relationship as both are structural component of  plants, while obviously K (an ion not the structural part of plants) does not have significant relationship with these two ions. But since all the three element are essential for healthy metabolic functions in plants, must be related indirectly. 

  • Vadivel Sampath asked a question in Observation:
    Is there any difference between CV and Resume?

    In my observation I do not find any specific format either for Resume or CV.

  • Sandeep Roy Sarkar added an answer in SPSS:
    How can I do Hotelling’s T-square?

    How can I do the Hotelling’s T-square - for pair-wise comparisons of mean somatotypes of various age groups, between boys and girls.

    Can I calculate using SPSS.

    Is Hotelling,s Trace is same like Hotelling's T-square.

    Sandeep Roy Sarkar

    Dear Dr. Morse,

                SPSS will give Hotelling's Trace, and it has to convert to Hotelling's T^2 as follows:

    Multiplying Hotelling's Trace by (N - L), where N is the sample size across all groups and L is the number of groups, gives a generalized version of Hotelling's T^2.

  • Khalil El-Saghir added an answer in Teaching English as a Foreign Language:
    What role does learning about culture have for both the knowledge and motivation of EFL students?

    Most people seem to agree that learning about culture is part of learning a language, but the better we understand the ROLE that learning about culture plays, the more focused we can be about what parts of culture to teach.

    How important is learning the cultural meaning behind idioms?  How important is cultural knowledge for increasing motivation to learn?  Are there other benefits to teaching about native speaker culture?

    Khalil El-Saghir

    As Jeffrey alluded above and based on my own experience, I strongly believe that language and culture are inseparable and that the acquisition of one inevitably entails some level of transfer of the other. The construction of meaning, in EFL context, is normally fraught with ambiguity that is mainly due to cultural differences. Over time, the meaning is reconstructed via social and cultural interactions. It is thus highly important to incorporate variable aspects of cultural materials in the teaching of English to EFL students.

    On the other hand, the inclusion of EFL students’ own cultural contents in the curriculum, as Debra noted, may be highly motivational to the learners as they discuss and debate issues of personal interests. Choosing such cultural materials, however, may be a daunting and even controversial task. How can we be sure that they truly represent the mainstream culture and not some extreme yet vocal elements of those societies or those who are antagonist to the said culture? Take, for example, Islamic or Arabic cultures. Given the current political environment, it is rather more likely to find content materials that are on the outliers rather than the norm!

  • Vadivel Sampath asked a question in Mother Tongue:
    "Teaching Practical English Language Skills to ESL Learners" (Using Interactive practical Activities) Discuss the scope and possibilities on it?

    The hypothesis of the proposed research is “Learning English language can be easy more of practical than theory”. The probe will be on accessing the available practical teaching methodologies (like swimming) without any books and finding the result. The students in general have the fear of grammar before learning a language. In my observation language can be taught like their mother tongue. A baby learns the language without any grammar or intention. Likewise, language can be taught and grammar may be corrected later which is my argument. When a grocery store keeper acquires the language easily (practical learning), students miserably fail to communicate even after 15 years of study approximately. (Preschool, School, College) Almost everybody forgets the subject we studied either in school or college but we remind how to play chess or cycling. In my firsthand knowledge along with teaching experience I have observed that English is taught as a subject rather than a language. As a result, it is decided to probe into this practical method of teaching English to ESL learners.

  • Abdul Ghafoor added an answer in Colloid Chemistry:
    What is the difference between CEC and surface potential of a colloid?

    Soil Colloids

    Abdul Ghafoor

    Cation Exchange Capacity: Key Points

    I.            Cation exchange capacity (CEC) is the total capacity of a soil to hold exchangeable cations.

    II.            CEC is an inherent soil characteristic and is difficult to alter significantly.

    III.            It influences the soil’s ability to hold onto essential nutrients and provides a buffer against soil acidification.

    IV.            Soils with a higher clay fraction tend to have a higher CEC.

    V.            Organic matter has a very high CEC.

    VI.            Sandy soils rely heavily on the high CEC of organic matter for the retention of nutrients in the topsoil.

    Surface charge density (SDC) is defined as the amount of electric charge, q, that is present on a surface of given area, A:  then SDC = q/ A

    Zeta Potential Defined

    The electrokinetic potential between the surface of the colloid and any point in the mass of the suspending liquid is referred to as the surface potential.

    Any molecule covalently bonded to the surface move with the particle when it diffuses or is induced to move electrophoretically in an applied electric field. When wetting, dispersing or stabilizing agents are strongly adsorbed onto the surface, they too move with the particle. Counter-ions very near the surface, perhaps within the first nanometer or two also move with the particle. Finally, solvent molecules are sometimes also strongly bound to the surface.

    However, at some short distance from the surface, the less tightly bound species are more diffuse and do not move with the particle. So another imaginary yet useful theoretical layer is defined: the shear plane. Everything inside the shear plane is considered to move with the particle; everything outside of the shear plane does not. In other words, as the particle moves it shears the liquid at this plane.

    The zeta potential is defined to be the electrostatic potential difference between an average point on the shear plane and one out in the liquid away from any particles.

  • Pratim Parash Kalita asked a question in Static Analysis:
    When does Dynamic analysis give values of results less than 85% than that of the values obtained by static analysis?

    Is the structural orientation/ form/issues responsible for such a condition? 

  • Shyam Kondeti added an answer in Wireless Sensor Network:
    What are the new research areas in wireless sensor networks?
    I want to know about new emerging research areas in wsn.
    Shyam Kondeti

    Sujject me some  Topic  for research in wireless network

  • Angamuthu Manikandan added an answer in Soil Chemistry:
    When soil solution is concentrated four times, will K-Ca activity ratio in solution change?

    As we know that activity ratio is K /Ca or K /Ca+Mg  is influences soil solution.

    Angamuthu Manikandan

    Thank you Sir,

    As per example provided by Abdul Sir and Subba Rao Sir Formula

    I had solved the problem


    K = 4 mmol/L, Ca = 8 mmol/L, Mg= 6 mmol/ L then activity ratio of K -Ca  is = K/Square root of Ca+Mg = 4/Square root (8+6) = 4/3.74= 1.06

    , when conc increased 4-time, then

    K = 16 mmol/L, Ca = 32 mmol/L, Mg= 24 mmol/ L then activity ratio of K - Ca is = 16/square root (32+24) = =16/7.48= 2.13.

    Hence we can say as doubled K-Ca activity ratio.

  • Nidhi Sahu asked a question in Intelligence:
    How can we relate spirituality to enhance research skills of PhD students ?

    Research is a complex multi-factorial process that encompasses issues at all levels from that of individual students and supervisors, to available infrastructural support, to institutional and governmental policies, structures and procedures.Numerous factors have been identified significant predictors of successful completion of research Spiritual intelligence is the central and most fundamental of all the intelligences.Robert Emmons defines spiritual intelligence as "the adaptive use of spiritual information to facilitate everyday problem solving and goal attainment. some essential life skills  are very important for successful completion of research work like problem solving, decision making, information management, time management, creative and critical thinking etc. My area of study is how can we use concept of spirituality to enhance the research competence of PhD students? Any information or suggestion will be of great help.  Thanks and regards.

  • Ranjith Abeywickrama asked a question in Solvents:
    What is the correct methodology for bitertanol analysis in black tea using LCMS/MS couple with C-18 column and set (+)ve ESI mode ?

    Best solvents for A & B

    Solvent ratios

    time period

    retention time range

    Best solvent for black tea extraction

  • Mohd Arish added an answer in THP-1:
    Can anyone suggest NO assay for PMA induced THP-1 cell lines?

    few question to be answered

    1. what media to be used RPMI or DMEM media?

    2. do i have to pellet down cells before taking the reading?

    3. Can i make NO standard using culture media?

    Mohd Arish

    Thanks Bhai, cant we directly use 96 well plate for NO assay using ELISA as im working on differentiated THP-1 cells

  • Bhawna Gauri added an answer in Protein Digestion:
    How can I use fluorescamine for quantitation of total amino acids in a protein sample digested with 6N HCl?

    These are the samples on which hydroxyproline assay was performed. So the protein is digested with 6N HCl.
    Fluorescamine method won't give any significant readings

    Bhawna Gauri

    you can try boric acid buffer pH 9. Flurescamine gives maximum intensity at pH 9.0

  • Dingzhi Hu asked a question in Perceptual Learning:
    Feedback in constant stimulus method and perceptual learning?

    In constant stimulus method, will using feedback affect psychometric function? and will the time of the presentation of stimuli affect it?

    And another question is, is feedback necessary in pre-test and post-test of perceptual learning?


  • Chandrasekharreddy Guda asked a question in ArcObjects:
    How to identify and set reverse normals programmatically using Arcobjects?

    I am working a 3D-Buildings project, where deliverables are * .dgn and Esri Multipath, after conversion of *.dgn to multipath in ArcMap, noticed that few facades normals reversed ,results looks likes portions of the multipatch are missing. So, I have to fix those faces (inverted) programmatically. Please suggest how to fix these issues and also provide which interfaces can help to resolve these issues. please check attached image

  • Abdelrahman Mabrouk asked a question in Abaqus:
    Why stirrups are not working ??

    I made a  full model for a 4 point loading  RC beam  using ABAQUS and it gives very good results but it took too muck time. When i made the model for only quarter of the beam due to symmetry, shear failure happened because stirrups are not working !!! however the longitudinal reinforcement is working (i made all the reinforcement embedded) Can anyone help me ??

  • Rathan Samala added an answer in Hyperbolic Geometry:
    Can anyone suggest me how to find the solution of Inviscid Burger's equation with sinusoidal wave initial condition?

    Hyperbolic conservation laws

    Rathan Samala

    Thanks a lot to  all for  giving valuable information. 

  • Shahid Chaudhary added an answer in Lentivirus Production:
    Which one of the available commercial lentiviral production kit would be the best to work with and gives us the best results?

    With the available commercial lentivirus production kits, I would like to know which is the one best suits for the production of lentiviral particles to be transducted in tissue, with highest efficiency and high titre.

    Please suggest me whether we can clone our gene of interest in the vectors that would be provided in the kit. 

    Thank you.

    Shahid Chaudhary

    I agree with Jill Muhling. You can get all your lentiviral constructs plasmids off addgene and they will also provide you with range of plasmid encoding envelope of different viruses for higher transduction in variety of cells. Also you can clone your gene of interest in the plasmid vector provided simply by introducing restriction sites in the insert through PCR followed by cloning. Go for PEI mediated plasmids transfection in HEK293 cells for virus production and use PEGiT virus precipitation solution (system bioscience) for concentrating virus. I always get my virus titer in 1010-1011 range. 

  • Sharonah Esther Fredrick added an answer in Cross Cultural Studies:
    How can we decide whether to consider the variables as independent or moderator as in the case of Hofstede's cultural dimensions?

    How we can decide to consider the variables to be independent or moderator as in the case of Hofstede's cultural dimensions?

    Sharonah Esther Fredrick

    Wow, I find it a bit frightening that anyone would look at Wikipedia for serious academic information. Their articles are very inaccurate. Would you go to a biology aficionado if you needed an operation? Probably not, you'd go to a registered surgeon. By the same token, Wikipedia writers have no more authority in the Humanities than someone who just studied two years of biology would have in the event that he/she had to perform surgery.

  • Ishag Adam added an answer in Plasmodium:
    What are the differential features between Plasmodium ovale and P. vivax?

    Plasmodium specie in the thick and thin films are somehow difficult to differentiate.

    Ishag Adam

    Thank  you very much  Miles B Markus for this good point.

    Perhaps we have no  good experience with P. ovale infections as it is rare in our setting

  • Henrik Rasmus Andersen added an answer in Chlorides:
    Could ferric chloride be the course for my chloride problem? Is it dissociating may be?

    I use ferric chloride (FeCl3) as a coagulant in my effluent treatment. on one particular run the concentration of chloride ions is twice the chlorides in the feed. Why is this so? Why am I ending with a high concentration of chlorides at the end. other parameters like, pH, Conductivity, TSS, Turbidity, COD, and Sulphates concentration have been reduced quite significantly. Please help.

    Henrik Rasmus Andersen

    Ferric chloride is about 65% chloride by mass so if you are dosing 10 mg-Fe/L you can expect about 19 mg/L chloride increase. In practice a bit more can be expected as ironsalts for wastewater might not be 100 % pure.

  • Nishanth Gabriel added an answer in FGF:
    Which media is suitable to grow rabbit bone marrow MSCs?

    I have tried using DMEM (low glucose) and alpha MEM to grow MSCs isolated from rabbit. They are showing poor growth (means less cells were adhered and took long time to reach confluent). Later I tried DMEM/F12, and it was showing better growth but the cells are reaching senescence very early. I will be grateful if anyone can suggest the right culture media.

    Supplementing FGF in DMEM/F12 has been tried but the results are not so encouraging.

    Nishanth Gabriel
    Haven't worked with rabbit MSC but have worked extensively with human and mouse MSC. Check your serum. Some serum lots are better than others. These days you have MSC graded serums. Ask the vendor to get you a small sample to evaluate. Insist on checking the serum before ordering. Try isolating MSCs from younger animals. MSC seems to grow faster from young subjects. I always felt alpha MEM was way better than DMEM. So isolate cells from young animals, stick to alpha MEM and evaluate different serum at 15% dose. You can evaluate dose once you have got the optimum serum source.

    Another way is to screen the literature, make an excel and see what are the common media component as given in different papers. I did this when I was confused for MSC differentiation cocktail. And then I read what the role of each of those components in differentiation and made a good differentiation cocktail.

    Hope it helps.
  • Anand Pai added an answer in Aluminium:
    Any advice on Aluminium cast with polymer?

    Can Aluminium cast together with polymer material ( eg. PE or PP) to produce self lubricated composite by using sand casting route?

    Anand Pai

    Which polymer are you trying to use?

    Apart from evaporation, Some thermosetting polymers undergo charring and leave behind carbon. If you encapsulate the thermoset powder in aluminium foil ~ 0.5 mm thickness , preheat to 400-4500C, then disperse it during stirring of Aluminium melt, you may achieve a fair distribution of the charred particles within the Aluminium matrix. But I have my doubts on the improvement in self-lubricating property of such materials.

    However, you can try using graphite as a dry lubricant filler for Aluminium alloys in order to improve the self-lubricity of the composite.

  • Mohamed Aly Elkhodiry added an answer in Gold Nanoparticles:
    Can anyone recommend a software or script to create structure (.pdb or .gro or .xyz) files of surface-coated gold nanoparticles?

    I would like to do MD simulation of surface coated gold nano particles. I require structure file of surface coated gold nano particle. Can somebody suggest me any software or script to generate these structure. 

    Mohamed Aly Elkhodiry

    depends on your goal afterwards but consider COMSOL

  • Jibran Khan added an answer in Geoinformatics (GIS):
    Any advice in assigning weightage to the spatial layers for GIS based multi-criteria decision analysis?

    Considering the scenario of GIS usage for multi-criteria decision analysis to evaluate the land suitability, do you think is it appropriate to assign weightage to the spatial layers based on the published literature?

    Jibran Khan

    @Garcia and Vijith: I am trying to develop a land suitability map for the utility scale solar power plants for non-urban area of region of interest. The parameters to be considered are: slope, insolation, distance to roads etc. I will surely look into the material you suggested.

    I was wondering that the topography of any location does vary (and consequently the incoming solar radiation and climatic conditions) so assigning weightage to spatial layers based on published literature will be appropriate.

  • Ebenezer R.H.P. Isaac asked a question in Gait Analysis:
    What is the literal difference between gait and walking process?

    Though most most people use gait and walking interchangeably, Dr. M. Whittle in his book on Gait Analysis: An Introduction specifies a difference as

    "the word gait describes 'the manner or style of walking', rather than the walking process itself."

    How will you differentiate manner of waking from process of walking?

  • Jose Hodak added an answer in Copper Nanoparticles:
    I have synthesized copper nanoparticles by laser ablation in liquid. I want to find the concentration of the colloidal solution. Can anyone help?

    I have recorded the UV-visible absorption spectrum and have also calculated the average size using TEM.

    Jose Hodak

    In the case of copper, and since you know the average size, you may be able to estimate the average particle concentration if you know the total copper concentration in the colloidal solution. The most acurate way to do this, would be to use atomic absorption in a flame or if you have it available, use atomic absorption (AA) in  ICP (Inductively coupled plasma) . You may need to take your colloid, and convert all the copper into Cu+2. You may achieve this by adding nitric acid to  a known volume of the colloidal solution. Perhaps 40.0 ml of the colloid, place them in a 50.0 ml volumetric flask, and then complete with Conc. nitric acid, up to the 50ml mark. Leave it to react until all the copper is converted to copper ions (pale blue solution).  Then build a calibration curve. This calibration curve should has to cover a suitable range so that  the concentration and the absorbance of your sample fall in the calibration range. (initially you may try a 0-1000 ppm using 200 ppm increments. prepared using copper nitrate in nitric acid of the same concentration as that in the sample) For copper, in the AA instrument with a 10cm flame, set the monochromator to 280nm. using a hollow cathode lamp with a current of 5 mA and a slit of 1nm. For the flame, you may use acetilene(30psi)-air(8psi) mixture. Copper also has another absorption line at 324nm but i am not sire which one has the best sensitivity. However, i believe it should be easy to detect even 0.05ppm of copper using this technique). 

    Run them the 6 standards, trough the atomic absorption,, register the absorbance, build the calibration curve, then run your sample. If the absoerbance of your sample is too high make a dilution. If it is too low, make a new series of standars in the 0-100 ppm.  If you need to concentrate your sample, you may need to precipitate the copper in some way and use a centrifuge to collect the solid. Then,  you need to make a sample in a smaller volume by taking the precipitate back into a solution using conc. Nitric acid.   This is a crude protocole, but it will get you a good estimate of the concentration.