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- 3HOw to check Mediation by one variable between two other variables, eg Mediating role of X ON A and B using SPSS?
How to do this in SPSS
You are most welcome.Following
- 1Could anyone please guide me about the lowest bounds on the masses of scalar and pseudo scalar?
Some of the flavor calculations put very stringent bounds on the masses of the additional scalars. I just want to confirm the lowest bounds on them.
this is a very model-dependent question. In particular, you have not specified the representation (i.e. the charges) of the scalars you are looking for.
Example collider limits can be found on pdgLive:
However, there can be many other limits e.g. from consistency arguments on the scalar potential or from LFV or similar.
Thus, I am afraid, there is no simple answer in case you were asking for only two numbers.
- 5How can I predict the ribosome binding site in bacteria using PC?
I'd like to ask You: does anyone know a software for finding a ribosome binding site? Let's say where in this sequence GAATGTTTCAGCCTTAGTCATTATCGACTTTTGTTCGAgtgGAGTCCGCCGTGTCACTTTCGCTTTGGCAGCAGTGTCTTGCCCGATTGCAGGATGAGTTACCAGCCACAGAATTCAGTA is Shine Dalgarno sequence? It is sequence od dnaA gene of e.coli (small letters = start codon).
Thanks for your good suggestion in advance.
You can also try the RBS Calculator in prediction mode. Go to https://salislab.net/software/reverse, copy/paste your mRNA sequence into the box, and click 'submit'. In your results, you'll see the predicted translation initiation rates for each of the start codons in your inputted mRNA sequence. The model takes into account all known biophysical interactions between the ribosome and mRNA.Following
- 6What is the phenomenology of law?If there is such a thing as law (or music to which it is analogous), what else is true?
Is a translation to English available? If not, I have someone who may be willing to help me.Following
- 4Are there any pitfalls one should be aware of when using maximum likelihood?
When estimating a given model's parameters, is there any condition that makes maximum likelihood undesirable and/or inneficient? In such a case, which would be the better method?
What kind of models are you considering? To use MLE you need to know the probability density function and you have to assume random sampling. The classical example is when estimating the parameters in a regression model (the coefficients and the variance of the error term). There is an old theorem that shows that the MLE estimator is the same as the least squares estimator(s) when the response variable is multivariate normal. This result is related to but not the same as the discussion of whether the MLE is consistent.
Your question is posed in the "geostatistics" forum but the assumptions pertaining to kriging are quite different and in general MLE would not be applicable.Following
- 1What software can I use to apply autoregressive conditionally heteroscedastic model on my data?
I never used any statistical software before and I have been working with excel only, I would be thankful if you could suggest something easy to use for a beginner.
I suggest that you try PSPP. It is an open source alternative (clone) of the commercial SPSS software for statistical (and other) analysis.
You can find the download link in the description below.
Also, there is a quick tutorial available on the second link that will help you get started with PSPP. It is really for the first steps. To learn how to get your data into the sheet and how to perform simple transformations, mapping and analysis.
If you want to get into details and nuances of the program, I suggest that you check out the third link, which is the near-complete documentation index.Following
- 99+The gravitational redshift is a phenomenon based on gravitational time dilation, don't we want to exclude definitely any loss of energy of photons?
The gravitational Redshift is a phenomenon which is directly related to the time dilation of the atomic clocks in a gravitational potential. Somebody still gives the interpretation of an energy loss of photons in a gravitational potential.
If the interpretation is due the exchange of net amount of energy with the gravitational field while crossing different gravitational potentials, treating the radiation as being massive while travelling, such hypothesys has to be excluded. The results of the PRS experiments verify (1+gh/c2) as being the frequency shift ratio, and since in both cases (lossive and clock hypothesys) the same shift is predicted, one of the two interpretation has to be discarded.
Lev Okun invited to perform such a sharp distinction more than 15 years ago, discarding forever the gain or loss of energy of the photons as measured always in the same RF.
The two interpretations cannot be considered alternative views of the same phenomenon and the net electromagnetic energy exchange with the gravitational field during the transit has to be discarded and is not certainly supported by the GRT.
The Clock hypothesys is verified also in the experiment of Vessot and Levine by testing the Schwartschild solution . It is also verified that when clocks are in sync in a gravitational potential, due to the compensation of the kinetics, there is not redshift at all, In other words, although there is a different gravitational potential between the emitter and the observer, there is a specific point along the ballistic motion where no redshift is observed or present, and no time dilation between the emitter and observer is present according to GRT.
- 6Clipping rasters to polygon?
I'm trying to calculate the Leaf Area Index (LAI) of different vegetation species in each state in the US and I'm using a netcdf (.nc4) raster file for the LAI and a usual shapefile (with polygons) for defining the state boundary. I converted the net cdf file into a raster file using the "Make NetCDF raster layer tool". I'm using the Clip tool (< Raster Processing < Raster < Data management tools < Arc toolbox) in the arctool box to clip the raster layer and the polygons. So in this case, my output extent are the states that I choose from the shapefile and the input raster is the raster layer of course. I also checked the "Use Input Features for Clipping Geometry" option so that the raster dataset is clipped onto the perimeter of the shapefile.
Here is my question: Sometimes, there are additional pixels that are created in the output raster dataset, that are actually not present in the original input raster layer. And these pixels also have a value associated with it, which is a cause of concern since some states which should actually have a zero value in it, have a random number in the output file.
Could someone explain what's happening or the possible reasons for this?
I have GCM data in the form of netcdf data type .i want to extract my Area of interest by polygon.In arcgis 10.1I tried Spatial Analyst Tools -> Extraction -> Extract by Mask and clip tools but its not workingFollowing
- 7Does anyone perhaps have a mouse vessel/capillary isolation protocol which isolates both the vasculature AND associated mural cells?
I have been using a 40% Dextran gradient centrifugation protocol with HBSS to isolate mouse capillaries (from cortical homogenate) but have not found any of my pericyte or smooth muscle cell markers in my vascular fraction (or at least not to any where near as high a yield as in my parenchymal fraction). I would appreciate any insight/help. Thanks!
Would you be able to forward me a protocol? Thanks!Following
- 1How is the photocurrent with ohmic contact setup affected by Space Charge limited current?
We get photocurrent by substracting the dark current from the total current in presence of illumination. This approach works within the Ohmic regime where the dark current is because of thermal carriers (J=n*e*mu*E) and the photocurrent is because of the photogenerated carriers (Jph = Delta n*e*mu*E). Extend this to both types of carriers if you wish.
In dark, if we keep increasing the voltage, when the carrier transit time becomes smaller than the dielectric relaxation time, the current reaches into the Space-Charge-Limited Current regime where the current becomes carrier concentration independent (Mott-Gurney Law)
Since the dark current is already carrier concentration independent and depends on the internal field distribution because of the injected carriers (from injecting/ohmic) contacts, how does the small number of photoexcited carriers contribute to the photocurrent (remember the current does not depend on carrier concentration in SCLC)?
There are authors and papers performing photoconductivity experiments with ohmic contact to obtain mobility-lifetime product of the carriers using Hecht analysis where they use the concept of photocurrent saturation at high fields. Their high fields extend well over the voltage where the device actually gets into SCLC regime. Why don't these authors care about SCLC? does not SCLC interfere with photoconductivity?
The worst condition is when they talk about surface absorption case. In SCLC, the carrier concentration at the injecting surface is infinitely large. How does a small photo excitation of charge carriers at surface (where there are already infinite injected charge carriers) show a significant result for the photocurrent to be extracted? Or in other words, when there are already infinite injected carriers on the injecting surface, can we even excite more carriers with light?
Note: The space charge I am talking is not the space charge because of photogenerated charge carriers, but is because of the injected charge carriers from ohmic contact (Mott-Gurney law).
Can any one please suggest where I am going wrong in understanding, and/or give some references where photoconductivity and space charge limited current are described together?
With the space charge limited current (SCLC) method, one can calculate the mobility of a organic semiconductor with a simple IV curve. The SCLC is a description of a behavior of the voltage dependence on the current in a semiconductor. SCLC occurs when the charge carrier concentration is larger than the doping level or the free carriers in a semiconductor. This can happen by injecting charge carriers into the device. This current is dominated by the applied field, what one calls a drift current. The high charge carrier concentration affects the electric field distribution, which makes a feedback loop between the field and the current. This feedback mechanism is described in the relation called : Mott-Gurney law.
The simplest way to measure the resistance (R) of a device is with two contacting wires. By sourcing a current (I) one can measure the voltage (V ). After Ohms law R = V/ I the resistance can be calculated Two wire conductivity measurements can be accurate, but there are some issues.
- Read more in this thesis: https://www.jku.at/JKU_Site/JKU/ipc/content/e166717/e180430/e180447/e180472/thesis-kraner.pdf
Where the experimental setup shows an equivalent circuit diagram of a 4 wire setup. R1 represents the resistance of interest. R2 and R5 includes the resistances of the cables to the current source A and the contact resistances from the wire to the devices. R3 and R4 refer also to the resistances of the contacts to the device and the cables to the voltage meter. In order to measure the resistance R1, the power supply (A) should regulate the sourced current accurately. This would make the voltage over the device independently of R2 and R5. To measure to voltage drop over R1 independently of R3 and R4, the internal resistance of the voltage meter (V ) should be infinite. In practice one can choose a voltage meter with a very high internal resistance or at least much higher than R1. With this configuration the calculated value of R1 is almost independent of R2 − R5, which is the purpose and advantage of the 4 wire conductivity measurement.
- 7How to distinguish shale from slab and rocks type between them ?
How to distinguish shale from slab and rocks type between them ? how to comfirm whether the low grade metemorphic mud-like rocks can generate gas or not ?
If I do not have a special reference book/paper, I would first consult the "Glossary of Geology" (or any other geosciences dictionary) for initial information. They commonly list key reference papers. I am sure there are sedimentary glossary or reference books, but as a metamorphic/structural guy, I don't own any of these.Following
- 4What are the new trends in Asphalt Modifications?
What Type of modifiers/Additives are in HOT research topics nowadays?
Nowadays, Microfibers play major role as asphalt binders/ mixtures modifiers.
Scientists and Engineers are trying to improve asphalt pavement performance and enhance the engineering properties, which are gained from the fibers; by control the fatigue and permanent deformation with increasing the resistance and increase the service life of asphalt, which is make the pavement more stable, durable and better moisture resistance.
there are a lot of microfibers in available in the market so you can check out..Following
- 1What's the best aggregation index in 3D environment?
I want to know what's the best index to measure the spatial clustering (aggregations) in 3D environnent.
Thank you in advance
Depends on the type of spatial data that you are working with...
So...what type of spatial data do you have?Following
- 2Can somebody Provide me the tutorial for the combustion in diesel engine using species model or non-premixed combustion model in Fluent ?
I am looking for some useful and step wise tutorial for the combustion of diesel in compression ignition engine. I am specifically looking for a combustion of diesel using Species model or non-premixed combustion model in Fluent.
I will really appreciate any help provided.
Thank you so much for your help. I really appreciate it.
- 15Is there any framework to develop an LGBT sensitive intervention?
I am currently working on developing an intervention to increase awareness about testicular cancer and other testicular abnormalities. I want the intervention to be LGBT sensitive. Is there any framework to guide my query? the educational intervention can be in the form of an app, a brochure, an e-brochure, and infograph etc.
- 4Does anyone know measures of gender essentialism, or lay theories of gender?
I want to measure peoples' conviction that typically "male" and typically "female" behaviour and skills are biologically based and fixed vs. culturally determined and malleable. It could be something akin to racial essentialism measures like the one below...
No, S. et al. Lay theory of race affects and moderates Asian Americans’ responses toward American culture. J. Pers. Soc. Psychol. 95, 991–1004 (2008).
The Lay Theory of Race Scale
1. To a large extent, a person’s race biologically determines
his or her abilities and traits.
2. Although a person can adapt to different cultures, it is
hard if not impossible to change the dispositions of a
3. How a person is like (e.g., his or her abilities, traits) is
deeply ingrained in his or her race. It cannot be changed
4. A person’s race is something very basic about them and
it can’t be changed much.
5. Races are just arbitrary categories and can be changed if
6. Racial categories are constructed totally for economic,
political, and social reasons. If the socio-political situation
changes, the racial categories will change as well.
7. Race does not have an inherent biological basis, and thus
can be changed.
8. Racial categories are fluid, malleable constructs.
- 5Can anyone send me references on gender and genius, creativity and aesthetics?
I am particularly interested in difference feminism (Kristeva, Battersby) etc.
- 5Are there any conceptual papers or literature review papers available for the topic of "gender studies" and children'consumption?
I am looking for papers which deal with the problem of gender and how this variable can condition the answer of kids and their consumption method.Following
- NewIs there any record of the positive effect of portfolio on learners speaking and communication skills?
I reviewed the existing literature about the effects of portfolio and I noticed that it has positive effect on reading comprehension and writing. Do you think that reflection on a paper can have positive effect on speaking and communication skills or no?Following
- 99+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?
Is it possible to evaluate fidelity and transparency of Rosetta Stone?
Wiki: " Fidelity (or faithfulness) and transparency, dual ideals in translation, are often at odds. A 17th-century French critic coined the phrase "les belles infidèles" to suggest that translations, like women, can be either faithful or beautiful, but not both.
Faithfulness is the extent to which a translation accurately renders the meaning of the source text, without distortion.
Transparency is the extent to which a translation appears to a native speaker of the target language to have originally been written in that language, and conforms to its grammar, syntax and idiom.
A translation that meets the first criterion is said to be "faithful"; a translation that meets the second, "idiomatic". The two qualities are not necessarily mutually exclusive."Following
- 1Why the increase temperatures absorption peak uv-vis protein bovine serum albumin reduced?
Effect of temperature on protein stability.
Whether due to decreased absorption due to temperature increase is related to the denatured of protein structure.
Please guide me.
How large is that temperature increase? Denaturation affects protein absorption spectra for sure, but your observation has most likely a much simpler reason. To figure out what is that, think about what quantities are determining the measured absorbance values. Which one is changing with temperature? How?Following
- 5What is at the top of your list for recommended reading on gender diversity and why (book or article)?
My goal is to get a cross-disciplinary perspective.Following
- 2Innovations & real penetrations of Technologies is relatively slow in Agrarian sector in comparison to Industrial or any other sectors? How to Perk up
Agriculture is a dominating occupation across globe and most important livelihood means at least for people living in developing nations.
Lot of innovative technologies are being evolved across the disciplines which have vast potential & applicabilities irrespective of discipline, where and for which it is developed.
What is needed is a fast Imagination, Recognition , Budding, Espousing, Expansion, and Penetration up to end client.
What I feel, is that ' It is being relatively slow in agricultural domain, where people still remains hesitant to change mind set, to have trust in new technology, to take risk..and they just wait and watch other sectors making faster experimentation in this regard. Life of technologies is shorter now a days, so by that time that technology gone...and so on..
Its a burning issue in my mind, looking into the prevailing situation of farmers specifically in tropical regions, where agriculture is still being taken as an art ...art of growing grains/crops to cater the feeding needs....not the smart business to grow income and live life of high standards...
I know its an unusual question..but I invite valuable feeds to enrich mine sphere ...
But I only partly agree. In present days agriculture is at cross roads. it has the extreme potential for being designated as biggest industry to cater items and services related to food and happy living environment. We need to change our mind sets from grassroot level to high policy makers and be more ready to accept and grasp technological innovations at same pace what other sectors are doing. Time has gone to do agriculture for meeting eating demands, its time for redesignating farmers as real agricultural business persons and harvest benefits , which are away from them because of enormous middlemen or breached policy links.Following
- 9What methods can be used to evaluate policy?
I'm looking for qualitative methods to evaluate policies concerning gender equality.Following
- 19What bible (old/new testament) says about the intersex?
Respected Scholars! What are the sayings/views about intersex and trans people (Jesus) an old/new Testament/Version? I am entire need of it for my research.
- 41What is the optimum sample size for factor analysis?Number of initially variables varies from 8 to 50. In some cases even it is more than 50. Let us assume if one has 20 initial variables, what will be optimal sample size for the purpose of collecting data.
Factor analysis (and also PCA) is a data analytic tool/method. As pointed out by Cameron Paul Hurst the use of EFA as an inferential method is questionable. Treating the data as a "sample" implies you are intend to apply the conclusion to the population from which the sample was drawn. However the derivation of the equations for EFA usually are not based on any statistical assumptions (although sometimes multivariate normality is assumed). EFA is best used to ask questions about the data set itself in which case the question of the sample size is not relevant. Finally EFA (and PCA) are multivariate methods and sampling design is more complicated in that case.Following
- 6Dear Colleagues. Could some body can help me to know or to have a good software for searching a differents conformers of a giving chemical structure?
Many thanks for your help.Following
- NewAny ideas how to neutralize Benzalkonium chloride (BC) in a solution ?
I want to use a particular compound to treat cells. The vehicle contains Benzalkonium chloride.(which is killing the cells). Any ideas how to neutralize the biological activity/toxicity of BC? I've tried using lecithin and Tween 80. They both kill cells. Running out of ideas. Thanks!Following
- 1Can foliar inoculation method can applied for post harvest fruits ?
i want to make spore suspension of my fungus
First make broth culture of your fungus in suitable media, then after centrifugation Vortex the ppt with 0.01% MgSO4 soln. Foliar inoculation method can be applied to post harvest fruits.Following