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- 3I have a plant sample and want to find out the phytochemical constituent of its dried leaf. Is LC/MS of crude extract be right technique?
I want to do phytochemical screening of the plant. will lc/ms be the right technique to do it from crude extract. how to interpret LC/MS data?take care dehydration not more than 40 C, or 55 C under vaccumFollowing
- 3Please suggest whether the method is correct to determine encapsulation efficiency?
Please suggest whether the method is correct to determine encapsulation efficiency
ex. Suppose you added 100 mg of drug in formulation and total content of your formulation is 1000 mg including drug.
it means 1000 mg powder contain 100 mg drug.
If your yield is 500 mg,
it means theoretically
500 mg powder contain 50 mg drug.
50 mg powder contain 5 mg drug which corresponds to 100 % encapsulation
In order to check it practically,
Take 50 mg of formulation, dissolve it in solvent in which your drug and polymer is soluble and measure drug content
if you get 4 mg then
use formula: Practical Drug Content × 100/ Theoretical Drug Content
Encapsulation efficiency= 4 *100/5 = 80 %
Please suggest if it is wrong or right
- 11How can an educational institution at the university level help elderly people in the sphere of social and health care?
What are the options if there are possibilities for cooperation with certain institutions such as centers of social care or organizations of retired people? What kind of activities or workshops can be delivered having in mind the needs of social and cultural inclusion and a psychological and physical health of that kind of target population? The question targets elderly people as population, especially the ones that has been recently retired and have more free time then they are used to have, or the ones that are older and are not able to use technology or resources that are available by many social services. It is also very important to note that they may have specific health issues due to unhealthy nutrition habits or to their age. How can we, as educators, provide help and actively participate in improving their quality of life?
Thank you, once again, for your excellent ideas. You are so right! Elderly people are not always aware of the abuse, and the change of the approach should start from the educational system. I teach at the Faculty of education, and I think that there are so many things that may be done at the university level in the initial training of teachers in order to develop awareness of this kind of issues. In addition, the future teachers can work with younger students in the frames of moral education across the curriculum. It is a cycle, like everything in our lives!Following
- 1Regarding Software Maintainability ?
I have taken 22 different UML Class diagram( samples) of 2 different variables and first one contains 4 independent variables and second one contains 7 independent variables.In this situation can we apply ks test or which test can be applied in this situation?
Dear Bhawana Mathur,
Look the link. May be useful.
- 3Which one is best waterproof micro cam recorder for video shooting of treated fishes in aquaria for behavioural study?
Which one is best waterproof micro cam recorder for video shooting of treated fishes in aquaria for behavioural study?
» Sony RX100 III
» Canon G16
» Canon S120
» Olympus E-PL5Following
- 7Has somebody worked on related topics like motivations of social entrepreneurs creating social enterprises?
I'd love to share insights about social entrepreneurship, motivations regarding new venture creation, related literature, common methods, empirical data and analysis.
Glad to hear that you could find some more interesting titles in my Excel sheet. Thanks a lot for sharing the link, I can find the journal before February. I guess I need to wait for a few days until I have access to this article. The abstract sounds really useful for my research.
My research question at the moment is
"What are the motivations of social entrepreneurs to create a social enterprise?"
As this question is still very broad, I am doing the literature review to find the gap where I can contribute to. Meanwhile I also read about the methodologies, analysis, conclusions and future research sections.
This is my approach now: reading a lot from past articles to understand where the gap is and how I can approach it. So far, I found many articles asking this exact question and solved it in many different ways. I want to put it in the context in Germany as I could only find two articles in English. Will have a closer look at the German articles soon.
Due to my background in applied sciences, I face some challenges but I am slowly getting used to the academic approach, the expressions and way of thinking.
But I am still not sure whether there is a more effective way to find out what approach I will take to start the empirical research. It seems like a long way to go.
I wish you a lot of success with your research. Let me know if I can support you somehow.
- 69Does the detection of primordial gravitational waves really imply that gravity is a quantum particle interaction, and the existence of gravitons?
Does the indirect detection of primordial gravitational waves really infer that gravitational effects result from a quantum particle interaction, necessitating the existence of a mediating graviton to exchange energy among particles of matter (Krauss and Wilczek, 2014, http://arxiv.org/abs/1309.5343)? Or, more simply, is it merely evidence that at primordial mass-energy densities and distributions gravitational mass-energy/dimensional spacetime distortions can be produced at quantum scales?
General relativity very successfully describes gravitation as a dimensional distortion of spacetime (corresponding length contraction and time dilation) in the presence of condensed mass-energy. However, quantum theories describe the direct exchange of material force energy among particles of matter, mediated by boson particles. There is strong motivation to integrate gravitation, which is conventionally considered to be the fourth force interaction of matter, into the framework of quantum theory. However, no mediating graviton particle has been detected.
Please see http://www.nature.com/news/how-to-see-quantum-gravity-in-big-bang-traces-1.13834 http://www.eurekalert.org/pub_releases/2014-03/nsf-nrs031814.php, http://www.nature.com/news/b-mode-1.14884 http://www.nature.com/news/telescope-captures-view-of-gravitational-waves-1.14876 http://physicsworld.com/cws/article/news/2014/apr/10/have-galactic-radio-loops-been-mistaken-for-b-mode-polarization
http://www.nature.com/news/milky-way-map-skirts-question-of-gravitational-waves-1.15181 http://news.sciencemag.org/physics/2014/05/blockbuster-big-bang-result-may-fizzle-rumor-suggests http://www.nature.com/news/gravitational-wave-discovery-faces-scrutiny-1.15248 http://www.nature.com/news/no-evidence-for-or-against-gravitational-waves-1.15322 http://arxiv.org/abs/1405.5857 http://arxiv.org/abs/1405.7351 http://www.nature.com/news/big-bang-finding-challenged-1.15352 http://www.nature.com/news/big-bang-blunder-bursts-the-multiverse-bubble-1.15346 http://news.sciencemag.org/physics/2014/06/bicep2-paper-published-big-caveat http://physics.aps.org/articles/v7/64 http://physics.aps.org/articles/v7/65 and http://www.gravityresearchfoundation.org/pdf/awarded/2014/Porto_2014.pdf.
Also see http://www.nature.com/news/full-galaxy-dust-map-muddles-search-for-gravitational-waves-1.15975 and http://arxiv.org/abs/1409.5738.
No-the detection relies on classical properties of gravity. While gravitational waves are described as coherent superpositions of gravitons, the ``shot noise'' of gravitons isn't detected this way.Following
- 90Who would fund this falsification of GRT?Excellent suggestion, but it would never get funded, because it would falsify GRT. Light is a wave, not a particle and thus is unaffected by gravitation. A ref you might like to cite:
Dowdye, Edward Henry, Jr., 2009, Astrophysical Evidence Clearly Shows no Direct Gravitation-Electromagnetism Interaction (http://www.extinctionshift.com/SignificantFindings.htm), in Volk, G., Proceedings of the Natural Philosophy Alliance, 16th Natural Philosophy Alliance Conference: Storrs, CT, Natural Philosophy Alliance, Mt. Airy, MD, v. 6.
you raise a serious question about research in physics and I subscribe also your criticism towards GR. Myself elaborated a critical theory not only towards GR, but also towards other theories of modern physics (SR, QM, SM) that are the basis of the present postmodern and mainstream physics. Now we are attending the usual din by newspapers, journals, televisions, websites about the last discovery of mainstream physics: gravitational waves. Mainstream physicists talk and write about fusions of black holes, of gravitational effects, of gravitational waves and all this would be happened billions of wears ago at unimaginable distances form the Earth. But many of those postmodern physicists are unable to understand gravity that is present under their feet. I subscribe what you write about the importance of the interpretation of an experiment that goes beyond the same experiment that is a cold fact if it isn't interpreted justly. Wrong interpretations happened very often in past time starting from the Michelson-Morley experiment, that represented the origin of modern and postmodern physics, until the most recent experiments. I agree with you: experiments are important but their interpretation is still more important: this truth isn't understood fully by postmodern physicists. Force of mainstream physicists consists above all in the fact that they are united to support in dogmatic way the same theories while alternative scientists are divided to propose different critical theories. In fact for instance you propose the existence of gravitons that have in your theory a largest speed that is much greater than the speed of light. Instead I am not convinced about the existence of gravitons even if I subscribe the speed of light may be exceeded. Until critical and alternative physicists are divided about innovative theoretical proposals the mainstream physics will prevail always.
- 2Any trained FACS coders out there?
I'm currently doing a research project on the facial display of complex emotions using FACS. It involves assigning FACS codes to a number of still pictures of posed emotional expressions. I've successfully completed the FACS coder training, but ideally, I need someone else to independently verify my coding. I'd be happy to reciprocate by helping out with any coding needs that you might have yourself.
I'm a certified FACS coder.
Feel free to contact me either here or at S3731873@unige.itFollowing
- 2In any boulder stream will the sediment be more affected by the shielding effect or by the large coherent structures generated by boulders?
Boulder streams contains the boulders of large size and have high velocities, there is a probability that due to the presence of large boulders, sediment will suffer the covering or shielding provided by these boulders to the sediments on the bed but also these boulders will help in generating large vortical or coherent flow structures which from the suggestion of literature helps in lifting of sediment from bed, my simple question is that which will prevail in boulder stream; shielding effect or large coherent flow structures?
Dear Mr. Sharma,
although it is very dificult to distil the essence out of your problem precisely, I would like to give you general piece of advice. Have a careful look at all those books and papers dealing or adressing so-called braided-stream drainage systems. Among those I would like to direct your view to the Scott-Type and Donjek-Type named according to Miall´s classification scheme from 1977. Here you will find a first-hand information and it will perhaps help you fine-tune your question. Afterwards, it will be easier to address this issue.
- 4Is Coefficient Alpha Robust to Non-Normal Data?
Would you like to help me? I have a question about a reliability test with non normal data distribution.
I have a data, N = 992, p values = 0.000 sig (Shapiro wilk / K-S). I use Likert scale, I use Cronbach Alpha to measure a reliability, and I use corrected item-total correlation for validity. But I have a doubt whether Is that a proper method or not.
Nunix W. Frentyna
Dear Peter, Dear Rainer, Dear David.
I apologize for the late response and thank you very much, it's really a great help for me. I'm really grateful for your kindness.
Thank you again, have a nice day and God bless you.
Nunix W. Frentyna.Following
- 95Can we design the orbit of a satellite with Einstein’s curved space?I think that the most successful theory of gravity is that the orbit of planet can be explained with this theory and the orbit of satellite was designed with this theory. To design an orbit of a satellite, the three of the factors of the orbit: 1) The radius, 2) The inclination angle, 3) The eccentricity, must be calculated. And, the Newtonian theory of gravity is the only theory that can calculate the three factors. In another words, if there was not the Newtonian theory of gravity, the orbit of the satellite could not be designed. It was known that, from Einstein’s field equation, the orbit of planet can be deduced. And it was used to explain the advance of the Mercury perihelion. But, I cannot find the method to calculate the three factors with Einstein’s field equation.
Kåre, you allways make me read! :-)Following
- 2I'm getting numerical singularity and excessive distortion error when I'm compiling UMAT with Abaqus. Can anyone please help me with this?
I'm working on the cyclic behaviour of soil using Cam clay model. For the material part, I found a umat code. When I ran my job without linking (using in built clay plasticity), I'm getting reasonable results. But when I'm linking with the UMAT, it is not even taking geostatic step and is showing excessive distortion. I'm attaching my .inp file and the umat code along with this. Please go through it and suggest me where I'm going wrong.
If this is your first attempt at using UMAT, try putting in elastic properties first/ print out a message from UMAT just to check the rest is working. Actually this is good advice even if it isn't your first shot at using UMAT.Following
- 2What are the physical and chemical properties of dead sea mud?
Dead sea is the lowest region in the world,and its very important to study the physical and
chemical properties of the dead sea.The properties of dead sea mud is investigated in many parts of the world,and we are asking for many researchers to undertake this question,and calling for many researchers to contribute to my question.Some researchers
were investigated for three different locations on the
astern shore of the Dead Sea . Due to its mineralogical
ntents, Dead Sea black mud replenishes the skin
inerals essential for renewal and regeneration by
moving toxins and dead cells with an exfoliating action.
cleans, purifies, and rejuvenates skin tissue giving a
righter complexion [3-4]. Black Mud also stimulates
lood and lymph circulation, increasing Oxygen intake and
raining trapped fluids. It is therefore effective in treating
llulite and in alleviating arthritic and rheumatic
Different skin care products, bath salts, and cosmetics
rge amount of this mud has to be collected, using
ecial scoops, from different locations on the shore of the
ead Sea, then transported by trucks to the company site
here the mud is pretreated and packed in small portions,
en shipped to different manufacturers.so how can we use this dead sea muds for medical and industrials?
Dear Alasadi Sir,
Please go through the following paper for the answer:
Khlaifat, Abdelaziz, Al-Khashman, Omar and Qutob, Hani (2010). Physical and chemical characterization of Dead Sea mud. Materials Characterizations 61(5): 564-568.
Dr. Arvind SinghFollowing
- NewWhy I get wrong sized band after heat shock transformation?
Hi dear scientists
I really need your advice. I want to clone my gene by length of 750 bp in pET 22 But I faced a trouble.
I’ve digested cloning plasmid(pGH 8) then extracted my gene using bioron gel extraction kit. After that I’ve done similar process for digested pET 22. Then I’ve read 260 od for each one and then perform ligation according to Neb formula for 2 hours at 22® C. In addition to check if ligation was successful I’ve done a PCR. PCR product size shows that ligation is done correctly. Then I transformed 15uL of my ligation product to 50uL of BL21 competent cell using EMBL heat shock transformation protocol. After that I want to screen correct colonies using pcr but unfortunately all colonies give bands with wrong size. Our pcr product size should be 939bp but as you can see no band at this region are available.(fig 1)
In addition pcr condition are set up as you can see its performance in detecting intact pET 22 in BL21(fig 3)
I repeat this process with another vector called pET26(fig 2)Following
- 11PV vs CSP solar technologies?
The energy demand has increased exponentially during the last decade and should reach 50 TWh in 2050. It is admitted that in the future, renewable energy sources should replace fossil fuels and reduce GHGs emissions which are responsible of climate change. The huge solar potential is pushing investments toward CSP and PV technologies . The two technologies are now in an open competition but PV is still leading with a comfortable ranking as a third source of Renewable energy. CSP technology still needs technical and economical improvement although it’s thermodynamically consistent.
thanks for your interesting answer details. But I know that particles in a sandstorm (for example) infiltrate every tiny space. It is a good concept for small and medium PV plants but for large scale PV power plants what will happen with production and maintenance costs?Following
- 3What are the UML diagrams that are popularly used with Agile Processes?
List of useful UML techniques for agile processes
Good work syed. Glad to see the comments from someone from my ex.work place. I was attached with APIIT (2001-2006) and used to teach UML based modules thereFollowing
- 3Does the Energy-dispersive X-ray spectroscopy (EDX) provide the chemical composition of the material as metals or metals oxide?
Does the Energy-dispersive X-ray spectroscopy (EDX or EDS) provide the chemical composition of the material as metal or metal oxide? i.e the results obtained from the EDX are in percent for metal or for metal oxide?
I found in different published papers that the data obtained from EDX are in % of metals and other papers as % metal oxide. When we use it as metals and when as metal oxide?
Is the following sentence right or false? EDX determines the chemical composition of materials as metals and exposes them as oxides but it doesn't mean that they are oxides. Many thanks for your reply.
EDS gives you only atomic composition. It can tell you that the sample contains, for example, oxygen and a metal, and the proportion between them.Following
- 4Do you know the best methods/techniques and tools to test the theory of acceptance and use of technology?
I have extended the UTAUT2 model and I have already developed my model hypotheses. I read about various methods/techniques used such as (Factor Analysis, Partial Least Square (PLS), Structure Equation Model (SEM), Regression Analysis) and tools such as (SPSS, Smart-PLS, Mplus, R, PLS-graph, AMOS). But I am not sure which one to use.
Please I would like some advice about recommended techniques and tools. I am really looking to find out what you consider to be the most efficient method and your rationale as cost and time are limited factors.
The book by Hair et al (**) is an excellent source for using the highly popular technique of PLS-SEM (coupled with the tool SmartPLS). It also includes guides you in selecting the right method for your research problem and setup (e.g. when you can use PLS SEM or Covariance-based SEM, or others.).
** Jr., Hair, et al. (2013), "A Primer on Partial Least Squares Structural Equation Modeling (PLS-SEM). SAGE Publications, Inc,Following
- 8Does the capital structure of a listed company affect its market value?
If yes, How? If no, Why?
In general, the decisions of capital structure are important. M&M (1958), argue the irrelevance of the financial structure regarding the impact on the firm value, in an "ideal world". Harris and Raviv (1991) believe that the leverage decreases due to profitability. The pecking-order theory (Myers and Majluf, 1984) maintains that firms with greater profitability require a lower amount of debt since they generate more internal resources to finance investments. By contrast, the trade-off theory suggests a positive relationship between profitability and debt, because the most profitable businesses have a lower probability of financial distress (Fama and French, 2002).
With regard to growth opportunities (as measured by market-to-book ratio or Tobin’s Q), there are divergent arguments regarding the sign of the relationship with leverage. While the arguments of the agency theory imply a negative relationship between growth and leverage (Jensen, 1986), the pecking order theory suggests both a positive and negative relationship. Myers (1977), for example, argues that the relationship is negative, as firms with high growth opportunities are more risky, since they have more volatile earnings and therefore have difficulty accessing low-cost credit. Even Fama and French (2002) maintain that high-growth businesses use less debt. By contrast, Myers (1984) argues that firms with high growth opportunities may use more debt to reduce costs arising from informational asymmetries and to send out a signal to the market with regard to the quality of investments. In empirical terms, while Michaley et al, (2015) found a positive relationship between leverage and growth opportunities, other studies found a negative relationship (e.g. Rajan and Zingales, 1995).
I also suggest to read Strebulaev, I.A., and Yang, B. (2013) The mystery of zero-leverage firms. Journal of Financial Economics, Volume 109, Issue 1, pp. 1–23.Following
- 1In R, is there any way to read data from the second, third,... sheets of .csv file?
In R programming, I need to import data from excel file. I converted it to .csv file so that the data import bacame fast. But the next problem came as to I was unable to read data from the sheets except the first one. Is there any way to tackle this? My major concern is that importing large amount of data from excel file takes more time as i have data in only the first two columns. Other columns are left blank.
Actually, csv files only have one sheet. You have to separately save the contents of each sheet - meaning, you'll have a separate csv file for each sheet.Following
- 1Is it possible for bacterial contaminated plant to grow healthy after sterilization?
For the past 4 months, i have been dealing with micropropagation of Neolamarckia cadamba plantlets. The plants have grown healthily with no sign of contamination. However, since the start of the new year, my plants have been contaminated by bacteria. I tried sterilizing them with bleach, ethanol and sterile distilled water. Still, contamination occured. And one time i tried cutting off part of the plants that have been contaminated, it was good for a few days. No contamination observed. But contamination happened again after a couple of weeks. Just recently, i tried again the sterilization method for my contaminated plants. So far, there is no contamination.
But i am concerned whether my plants will grow to be healthy again. The leaves have started to brown and wilting.
Microbial contaminated plant may not be a good explant for subculturing unless there is scarcity of procuring fresh explant material. There may be some endophytic bacteria? or fungi which may be present in the explant themselves which may not be eliminated by external sterilization. May be you could try to identify this bacteria and add antibiotic in small doses if it is helpful. Change of media or some other earlier study reference may be helpful to overcome the hurdle.Following
- 2How to calculate beats per minute (bpm) in sound?
I have a WAV file and I would like to know how to measure the tempo in bpm unit
This can be simply find using DAW s (digital audio workstation)using time warp too..........Following
- NewI did my Mphil from Sweden, Is it mandatory to take IELTS and GRE for admission in PhD Marketing Program in all the English countries?
While teaching at various universities, I have been advised by many of the colleagues that i must go for any English country. I came to know that IELTS and GRE is not required by many European universities but if one has been teaching, learning and working by using English language then any Non-English country may not be a competitive advantage in terms of pursuing PhD. Please guide in this respect !Following
- NewHow do i correct conflict in caledar in aquacrop model and how to calibrate aquacrop model and get statistical analysis for the years calibrated for?
I have created all the files for climate, crop, soil and initial conditions ( KEEP button is selected), for the project I have created multiple run successive years, my day 1 after sowing is 1st October 1979 and is to simulate up 28th January 1980 which makes 120 days to rich maturity for maize. the model is suppose to run up to 1989 that is 10 years, and is linked to the growing cycle, after selecting the project created the model says there is conflict in calendar so I wonder where I have made the conflict because my day 1 after sowing is 1 October even when selecting the crop file.
when I run the model I get statistical analysis for the first run, in the second run and those that follows there re no statistical analysis because it says limited informationFollowing
- 1Do you think CSR has to be the same meaning in all countries?
CRS has a lot of approaches, my question is if you think CSR has to be the same meaning (not practices) in all countries?
No, I would say certainly not. With a lot of differences between countries, their specific contexts and cultural factors, I would be really surprised if the answer to your question would be positive.Following
- 1How can calculate the total refractive index of a doped material?
if the susceptibility of materials A and B given by X1 and X2 (kappa), respectively, what will be the total refraction index if A be doped by B?
I have found some text. Especially the last one - Relation between nonlinear refractive index and third-order susceptibility in absorbing media - seems to be able to give answer to your question. There are of course some links which can be useful too.Following
- 1How can we differentiate among `Randomness`, `Uncertainty`, and `Stochasticity`?
Operational research, probability, stochastic optimization, stochastic process, probabilistic scenario.
Have a look at the following references:
- 1Are there any measurements to measure international opportunity recognition?
I am looking for measurements that measure international opportunity recognition regarding to entrepreneurial alertness, systematic search, prior knowledge and social network.
Thanks for your help
I believe you should refer to measures used in Global Entrepreneurship Monitor project. They are far from being perfect (in my opinion), but they are intended for cross country comparisons, so they should suit you.Following