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  • Anil Thakur added an answer in Himalayas:
    Need help in identification of attached Himalayan fern please?

    Place of collection: (Western Himalayas) Muzaffarabad, Pakistan. Altitude: 2000m; Time of collection: July-August

    + 1 more attachment

    Anil Thakur

    It is Polystichum species. You can check in some local Fern Flora.

  • Uma Jadhav added an answer in Space:
    Is comfort important than the space in architecture?

    Dear Researchers,

    Comfort and Space are two important qualitative aspects in architecture, where comfort leads to Physical behaviour and Space leads to Psychological behaviour - what is more important in architecture - Physical Comfort or Psychological needs of Space? 



    Uma Jadhav

    Thank you so much Napoleon Ono Imaah, Oluwafemi Samson Balogun, Miguel A. Callejas, Marković G. Đoko for sharing your perspectives on the subject.

  • Tirtha Das Banerjee asked a question in Butterflies:
    Any suggestion on removal of peripodial membrane from insect larval wing discs?

    I am doing in-situs on butterfly wing discs. The peripodial membrane is a big hurdle, as it must be removed to get good signals. Right now I am relying on mechanical removal of the membrane which is not very efficient and most of the time I am damaging the discs. Any suggestion is appreciated.

  • Krishnan Umachandran added an answer in Survey Research:
    Are "perceptions" survey research or case study or both?

    I have found that there is a "fine line" between examining "perceptions" of a specific group about a phenomenon using a questionnaire or doing so thru a case study using interviews. Which method is more appropriate for examining "perceptions"?

    Krishnan Umachandran

    Case studies may be quite exaggerating like a shadow, which the real count of quantity in a survey may not project, but can flow another thought process..

    For Example - see the picture enclosed (zoom and watch, the real camels are bright ones)

  • Sunita Gaind added an answer in TGA/DSC:
    Is is required to perform TGA-DSC for soil samples to measure the organic matter loss,or just the TGA analysis is sufficient?

    I have found from few literature s that TGA/DSC is just a comparison to calculate the organic matter loss.

    Thank you.

    Sunita Gaind

    Thermo-gravimetric analysis (loss on ignition at 550 oC for 4 h ) itself gives the information on loss of organic matter.

  • Afshan Shirkavand added an answer in Femtosecond Lasers:
    What optic can I buy to tightly focus a 1550 nm laser?

    This is more of a practical question about what optics are on the market. I have a 1550 nm femtosecond laser in fiber (100 fs pulses, 200 mW, 100 MHz, spectrum ~1500-1600 nm). 

    I'd like to focus this laser as tightly as possible (for coupling into hundred-nm-scale waveguides). Currently, we are using an aspheric lens from Thorlabs with NA=0.6.


    I've gotten quotes for custom aspheric lenses with NA>0.6, but they are very expensive. Is there anyway to beat NA of 0.6 without spending many thousands of dollars? 

    Afshan Shirkavand


  • Luisiana Cundin added an answer in Waveguides:
    Hi every one, Can any one tell me how to analyze the mode profile of waveguide structure. Means how to understand which mode is TE or TM ?

    Hi every one, Can any one tell me how to analyze the mode profile of waveguide structure. Means how to understand which mode is TE or TM  from FDTD solution?

    Luisiana Cundin

    Read Jackson's Electrodynamics,  section on waveguides gives a complete explanation, also, Balanis' book, "Advanced Engineering Electromagnetics".

    + 2 more attachments

  • Swati Asani added an answer in Proteins:
    What is the rationale behind fasting mice before sacrifice and what is the ideal time of fasting?

    It is a common rule to faste experimental mice overnight (~12h) before sacrifice. Does the fasting has any effect on the expression of Tight-Junction proteins affecting the gut-permeability?

    Moreover, what purpose does it serve when the animals are faste overnight? Its obvious that the effect would differ mouse strains (like ob/ob & c57bl6/J), but what is the general effect of fasting?

    Thanks :)

    Swati Asani

    Dear Priyankar,

    The ideal fasting period would be 12 h (overnight) as suggested by Mr. Saikat.

    However, to my experience, sacrificing at a fed or fasting state would depend on the kind of parameters you wish to study. for eg., if you want to study glucose transporter translocation or glucose uptake, you need to sacrifice animals at fed state. whereas, if you want to study parameters such as lipolysis or gluconeogenesis (which would be active at fasted state), you need to sacrifice animals at fasted state.

    Best luck!

  • Sachin Kumar Tripathi added an answer in Mississippi:
    Riverbed depth profiles of coastal rivers?

    I am looking for riverbed depth profiles of the downstream tract of major rivers. I am interested in the last few 100s km from the coast where river process interact with marine processes and backwater effects.  

    I have already found data for the Mekong, Mississippi and Yangtze rivers. Could you recommend where I can find data for other rivers?

    Sachin Kumar Tripathi

    Yes, we do have the longitudinal profiles data, but they were recorded within the creek channels and is not  representing the whole scenario of the river course. 

  • Jagannath Panigrahi added an answer in Ellipsometry:
    Oscillator function model for eosin yellow?

    We have a film of eosin yellow dye on glass substrate. We have tried building genosc model using Lorenz and GLAD. Also tried those of other polymers. But we are not able to fit the ellipsometry data. Any suggestions please.

    Jagannath Panigrahi

    Thank you very much sir for all your time. Will do as you suggested.

  • Snehaa Chandrakumar asked a question in Competent Cells:
    Can anyone help me in ruling out the issues in cloning siRNA into mammalian vector?

    Dear Researchers,

    I have been trying to clone my siRNA which has miR155 backbone into modified pcDNA3.1. I start with annealing of oligos followed by restriction, ligation (1:3 vector-oligo, 16 deg C overnight) and transformation. I don't find any troubles with the controls (Competent cells, undigested vector as negative control, restricted vector control and a check plate) I have used. I couldn't get positive clones in my target genes even after many trials. I will be glad to have solutions from any experts. 

    Thank you in advance

  • Tanuja Kosuri added an answer in Ammonia:
    Does ammonia evolve from a solution of NH4CL?

    Dear all,

    As per the literature NH4Cl when dissolved in water, its pH needs to be increased beyond 8.5 and preferably 10.5 (by addition of CaO) so that NH4+ is converted to NH3 and evolution occurs.

    My questions to you all is if I dissolve NH4Cl in water (to say 1000 ppm concentration) and heat this solution to 70-80 C, does heating also promote some losses of NH3?

    Tanuja Kosuri

    Thankyou Mohit ji, Prem Baboo ji and Mushtaq Ahmad ji for your valuable answers and clarifications

  • Sanjay Kumar asked a question in Distillation:
    How can we make a dilute solutions of antibodies in ppb range without wasting distilled water or other solvent ?

    Rapid diagnostics

  • Marcel M. Lambrechts added an answer in Tamil:
    Why is there an interval of (more than/only) 30.000 years between the first visible traces of art and writing?

    The first signs of art date from more than 30.000 years ago (e.g. cave art) whereas the first signs of writing (e.g. Tamil) appeared let say ca. 5000 years ago?

    Any idea why artistic humans waited such a long period before they decided to start writing?

    Marcel M. Lambrechts

    Do you mean that the rate of language change differs between languages (e.g. Tamil versus other)? Why then?

  • Ashish Bohre added an answer in Oxidants:
    How CO2 work as a source of oxygen in oxidation reaction?

    In many oxidation reaction researcher utilize CO2 as a source of soft oxidant. Can anyone  show me the mechanism? 

    Ashish Bohre

    Dear Prof. Smith, Prof. Geletii and Dr. Mavlyankariev,

    I really appreciate your suggestions.


  • Faheem Khan added an answer in Sugarcane:
    All bout Nitrogen in Sugarcane Field?

    Would anyone suggest me suitable techniques for nitrogen examination in sugarcane field ?

    Actually, I am working on a project to examine the presence of nitrogen in a sugarcane field.

    Kind Regards

    Faheem Khan

    Many Many Thanks Arvind Singh.

  • Himanshu Joshi added an answer in VMD:
    Problem in running VMD on Ubuntu.
    After installation of VMD, it showed: VMD installation complete. Enjoy!
    However when I tried to run it in terminal it shows: > rlwrap: command not found > /usr/local/lib/vmd/vmd_LINUX: command not found. What should I do?
    Himanshu Joshi

    Hi Rofiques,

    Why don't you edit the file as super user (root), I hope that will fix the permission issues.

  • Bahaa H Abdella added an answer in Taq Polymerase:
    Why is the ng more accurate than Sanger sequencing in generating sequences?


    I heard that the ng sequencing is more accurate than the Sanger sequencing in generating sequences. For example I heard that if I want to sequence a bacterial gene that I previously amplified with the Sanger method, the final sequence might  contain bases that are mutated because of the action of Taq polymerase. With the ng method this does not happen because you don't perform the PCR but sequence all the genome extracted by the bacterium.Even in case of mutations, the contigs will be generated based on the average of the sequence of the reads for that sequence. I did not understand very well what it means.. Do you have an idea?

    Thanks in advance.

    Bahaa H Abdella

    simply, I can say that Targeted resequencing by NGS machine takes short fragments of the DNA around 200bp to be sequenced, these fragments and each copy of it is sequenced then it has to be aligned with each other to generate the full fragment. think if you sequenced the same read more than 10 times could be a risk for nucleotide change only from Taq polymerase action?

  • Andrew Paul McKenzie Pegman added an answer in Nematodes:
    Is there any chemical which will not affect nematode activity but can change the color of leaf extract from green to colorless?

    I am trying to test plant extract for nematode suppression but finding difficult to read the number of nematode due to green colour of chlorophyll.

    Andrew Paul McKenzie Pegman

    Chlorophyll content actually decreased in nematode-infected plants. But see answers to the question 'How to remove chlorophyll content from plant material during soxhlet extraction?' by Guru Cowder on this site.

    I hope this helps!

  • Krishnan Umachandran added an answer in Behaviorism:
    What's the best way to teach virtue?

    Aristotle believes the intellectual virtues are brought about my learning. The moral virtues are learned by habituation. But this doesn't explain the quality of virtue. If we take a look at the Spartans, which saved the Greek world, they didn't reduce their laws to writing, they kept them in their chest. Aristotle believes the final test of virtue is through war. Nietzsche believed that one had to suffer the mistrust of others and loathe oneself. Chaos had to be ever present with him. It's a sort of wisdom through suffering. So its not just about learning, but its also about walking the path. Plato, believes in early childhood development theory that is akin to behaviorism. Herodotus, in his work The Histories, believed that virtue doesn't need to be found on the battle field but through devotion. This is found in the famous Solon meeting with king Croesus. The example is Cleobis and Biton. What's your take? What would present the best quality of virtue within one?

    Krishnan Umachandran

    Teachers as role models to teach virtue, will be the best way to reach students

  • Yurii V Geletii added an answer in Drawing:
    Which software does scientist use to draw figure and scheme?

    Figure and mechanism like this:

    + 2 more attachments

    Yurii V Geletii

    ChemDraw is the classical software for chemists. The best softwares personally for me are the  softwares, which I know how to use them. 

  • Matt Kalinski added an answer in Special Relativity:
    Trouble understanding Einstein's time?

    I have trouble to understand what Einstein thought about time: Not the fact that a clock was told to give me what I have to think of time to be implies some trouble but the many-sided, blurred ideas we were told to represent Einstein's time (t to be at rest,t' to be in motion, 'same' events to be viewed from different places, etc.)

    (Side note: Douglas Hofstadter on IBM's Watson: If this is artificial intelligence any meat grinder would eat meat).

    Students today are given the light clock to play around with and to learn relativity. But this model (this interpretation of time of the moving system) clearly does contradict Lorentz transformation when applying the interpretation of t' to be the time related to x'~x-vt (time in motion).

    Matt Kalinski

    The concept of both Einstein theories both the general and special is that the space-time is the entity by itself no matter what someone measures or percepts with conscioussness, like a piece of paper which would be pinned to a wooden table and could rotate around a pin. It exists as a piece of paper by itself no matter what the ruler measures on it between drawn points. What is drawn there like points is rotating and so changing coordinates with respect to the coordinate system steady with the table. To derive the two dimensional coordinate transformation it is enough to assume that the Euclidean (normal life) distance d**2 = x**2 + y**2 is the invariant as it is. The special theory is exactly the same except that instead the Euclidean distance the space-time interval s**2 = x**2 - c**2 t**2 is assumed to be invariant and than one asks what is the transformation to preserve it. It turn out to be the Lorentz transformation. The time is simply a number of counts the physical device (mechanical or electronic) is counting between the events (classical measurements of something at places) and this number transforms according to the Lorentz transformation. Or simply the motion is interpreted as the observation that it is a super-rotation of such entity assuming that such interval must be invariant. Such entity is Minkowski space with strange (-) sign entering the forth coordinate, the time times the speed of light in the "distance" on it.

  • Kushal Agrawal added an answer in SMEs:
    What are the factors that influence the adoption of Cloud ERP among SMEs?

    Currently writing my master thesis on the topic, a survey for new age SMEs (SMEs incorporated on or after 2010) is ready to roll out this week in EU member states.

    Kushal Agrawal

    @Hai Ping Fung,

    Thank you for your reply.

    I did consider TAM model, but it does not satisfy the questions I am trying to answer because Cloud ERP's "perceived usefulness" and "intention to use" are already existing, but still the migration has not been that evident. Moreover, there are no good means to classify the factors as some factors may be or overlapping in nature or might have a high correlation.

    The Unified theory of acceptance and use of technology has its components in "intention and behavior" direction, however my idea was not to go in psychology direction but keep it strictly on technology and organizational side and therefore I used the TOE framework.

    However, this would be a nice way to cross verify the outcomes and may be future scope of research, but thank you for your reply. Do let me know your thoughts. Am sure you know about the TOE framework here is the link to it.

  • Kiruthika Sivaprakash added an answer in Agarose:
    Yellow residue/stain in agarose electrophorisis for HA molecular weight determination?

    I've been having a reocurring problem where after destaining my gels there's a large smear of yellow/ochre pigment left in the <500 kDa region (see attached picture). 

    Has anyone had this problem? I'm trying to figure out if it's a problem with the sample, the sample loading dye (bromophenol blue) or with the stain (stains-all). 

    Kiruthika Sivaprakash

    Bromophenol Blue is a size marker in Agarose gel electrophoresis and also a pH indicator. It turns yellow, below pH 3 (i.e) acidic condition.

    If your gel is 1%, then probably BPB runs at around 500bp.

    I would suggest you to check the pH of buffer before and after gel electrophoresis to well answer this problem.  

  • Joel Christie added an answer in iTRAQ:
    Detailed/modified protocols for membrane proteins before iTRAQ labeling due to difficulty in resolubilizing?

    I am working on membrane proteins from entamoeba histolytica. Im using membrane protein extraction kit from Calbiochem, and I did acetone precipitation because the protein profiles are better when I run SDS PAGE. But, I have a problem of difficulty in dissolving the precipitated pellets after acetone precipitation. I tried to directly dissolve the pellet right after acetone precipitation with dissolution buffer and denaturant from the iTRAQ kit (0.5M TEAB & 2% SDS), but it does not dissolve. According to the iTRAQ handbook, there is a table listing all the alternative denaturants and detergents that can be use without interfering the iTRAQ labeling, one of the alternative denaturant is using Urea (<1M). I'm confused whether is it replace the original protocol's (1 ul denaturant, which is 2% SDS) with 1ul Urea (<1M) buffer? Or additional of 1ul Urea (<1M) buffer with added 2% SDS?

    Besides, I saw a lot of researchers doing iTRAQ did desalting after tryptic digestion. Since the next step is iTRAQ labeling, so is it have to desalt the samples after tryptic digestion and before iTRAQ labeling?

    Also, I did cation exchange using ICAT cation exchange chromatography (Sciex, 0.2 ml Cation Exchange Cartridges, SKU #: 4326695), is it mentioned can clean up the samples by removing interference substances but I'm not sure is it includes desalting samples. If it does not, can I use the Pierce C18 desalting spin column? Will it affects any iTRAQ labeled peptides?

    Sorry for tons of questions, thanks in advance for all!!

    Joel Christie

    I don't think 1M urea will work, b'coz for me at times 6M Urea even has not worked and had to add 200mM DTT along with it and gentle heat were given in that kind of situation; so as Peter said try avoiding Acetone precipitation; if you can and look for something like buffer exchange using cut off membranes.

  • Kuo Zhang added an answer in Innovation:
    What are the novel ways of improving technology backed by innovative systems and approach?
    The purpose of analyzing a Technological Innovation System is to analyze and evaluate the development of a particular technological field in terms of the structures and processes that support or hamper it. Besides its particular focus, there are two, more analytical, features that set the Technological Innovation System approach apart from other innovation system approaches.
  • Amanda Bullock added an answer in History of Geography:
    Are there any instruments for measuring teacher self-efficacy in interdisciplinary subjects, preferably in the social sciences?

    At the University of Goettingen, we want to design a questionaire testing teacher self-efficacy beliefs among teachers, who might have to teach Politics, History and Geography as one subject.

    You feedback is much appreciated!

    Marcel Grieger

    Amanda Bullock

    You could also check out the work by Tschannen-Moran and Woolfolk Hoy (2001). They have a Teacher Sense of Efficacy Scale. 

  • Swati Asani added an answer in Golgi:
    Can Insulin be used as Golgi apparatus marker ?

    can I use insulin it self as a marker for Golgi in immunoflurecense or I need another marker to prove that the insulin signal I get is inside Golgi ? 

    Swati Asani

    Dear Ibrahim,

    I agree with Tausif Sir that you need to label Golgi apparatus with another specific marker especially when you want to prove that insulin is within Golgi apparatus. As insulin might also be present in secretory vesicles, to differentiate between the two another labeling is a must.

    All the best!

  • Mousumi Bhattacharya added an answer in Emerging Markets:
    Condition of stock market emerging market countries right now?

    Dear professor and colleagues, 

    I would like to ask you some paper or dissertation and workshop related to Condition of stock market emerging market countries right now. I mean that I would like to know the condition of stock market emerging market countries now. Please send me the best paper that was published the last five years between 2010 and 2015 and I would be really appreciated to you for helping  due to I am writing the first chapter my dissertation so I need diamond paper and dissertation and workshop. Thank you very much in advance for those who send it to me   

    Best regards,

    PhD student


    Mousumi Bhattacharya