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- 5How do I calculate effective dielectric constant for a coplanar waveguide (CPW) and other related structure including antennas?
How do I calculate effective dielectric constant for a coplanar waveguide (CPW) and other related structure including antennas? Can you give me some reference.
If you do not want to use softwares such as MicroWave Office, you could use the coplanar mapping techniques to estimate the effective dielectric constants surrounding your coplanar geometry. There is a very useful text book on this topic, which covers many different CPW and microstrip configurations, where analytical conformal mapping expressions are presented:
N. S. Rainee, Coplanar Waveguide Circuits, Components, and Systems,
John Wiley & Sons, New York, USA, (2001)
- 13What are the best references in fictional literature to teach Philosophy of Science?
I intend to use classical books and stories to explore conceptual topics on Philosophy of Sciences. Can anyone suggest some references?
I am Japanese and not sufficiently understand Christianity. This"Ask a question" is about fiction but as Richard say "a philosophy based on ancient and medieval knowledge, and, on the other hand, the scientific method that was beginning to be applied in physics, chemistry and medicine"". But these two stream was theological experience are estimated for scientific ""paper. I recommend voltaire's "Lettre philosophiques (Philosophical letter-or letters Regarding the English Nation). In this book, modern physics' founder Sir Isac Newton is exactly introduced.Newton was now ascertained at the same time as an ardent alchemist. "He is a final alchemist of medieval or the father of modern science". Interestingly political thought of Lock also introduce in the same book. Bertrand Russel, novel winner of the British Empire, wrote very clearly and easy to understand. French and German translation continue to be published.Following
- 8What is the suitable method to evaluate "multiple management options" against multiple criteria/sub-criteria?
I am working on a framework to optimize surface water quality management strategies in catchments. I am looking for a suitable (simple as possible) method to evaluate the management options and rank them against fix cost/budget.
Did you think in MMwMf?. Is easy and maybe do you have a good answer.Following
- NewCan someone top help me to get answer for these question?
1-give an example of a zero dvisor in z=z3 and give a example of a non-zero divisor in z+z3(2)show that every group of order 21 have anormal subgrops of order 7#) find centerizer of(123) in s5(i.cs((123))=?(4) what is the cordinality of the conjwgacy class of s5 containing (123)?(FIND THE set or calcelate the cardinality )Following
- 9How can I clear plant powder from oil?
How can I macerate powder of a plant in a carrier oil and clear all of the plant powder from the oil?
I agree to all above answers. Only take precaution that as plant also contains natural oil that will also remove during this process.It is depend on extraction solvent used and temparature as well as time of extraction.Following
- 8How to define a new material model in DEFORM-3D FEM software?
We are performing turning simulation in Aluminum MMC composite reinforced with ceramic particles. What is the procedure in defining new material models for the cast MMC in DEFORM-3D? Valuable suggestion/procedures are needed at the moment.
Thank you all in advance.
Thanks a lot professor Mohamed Ibrahim Abd El Aal for your valuable suggestions.Following
- 4How do I calculate Kcat from Vmax and molecular weight of the enzyme?
Here is the case,
Enzyme (D) has Vmax value equals 813.7 U/mg, Km=3.9 mg/ml. Molecular weight 62 kDa.
The amount of enzyme used to determine these kinetics is 5 ug in 1 mL reaction volume.
I believed that i can do it as:
(Vmax/0.01612)/60 = 840 1/S.
0.01612 was obtained by dividing 1/62; as 62 is the molecular weight in kDa.
But when I refer to a few papers, I figure out that theis calculation misses something !!
I see now that the substrate concentration is measured in mg/ml because the substrate, agar, is heterogeneous in molecular weight. The catalytic rate, on the other hand, is measured in micromoles/min because the product, reducing sugars, can be measured in micromoles, using galactose as a standard.
The specific activity for the purified enzyme in the purification table, 517 U/mg, is not Vmax. The assay conditions used to measure the specific activity during the purification process (2 mg/ml) was lower then the Km (4.8 mg/ml), so the enzyme was not operating at Vmax.
Later in the paper, values of Km and kcat/Km are reported, with no data shown. Presumably these numbers came from a Michaelis or Lineweaver-Burk plot. Km (agar) = 4.8 mg/ml and kcat/Km = 390 (mg/ml)-1-s-1. Therefore, kcat = 390 x 4.8 = 1872 s-1.
I suppose the conversion of agarose mg/ml to mM is based on an average molecular weight.Following
- 3How do Reactive oxygen species affect the activity of a immobilized enzyme [Magnetic nanoparticle bound enzyme]? How we can prevent this?
How the Reactive oxygen species affect the activity of immobilized enzyme? The enzyme immobilized onto megnetic nanoaprticles.
How we can prevent this problem?
Dear ASHOK, we need more precision to answer this question. In general, ROS can oxidize the so called reactive cysteine in certain amino acids leading to conformational changes which may affect the type of interaction with the nanoparticule. To avoid this, adding antioxidants in the preparation is the simple solution.Following
- 97Why is there something instead of nothing ?
LET US START BY WHAT Robert Adler WROTE ON 6 NOVEMBER 2014--:
People have wrestled with the mystery of why the universe exists for thousands of years. Pretty much every ancient culture came up with its own creation story - most of them leaving the matter in the hands of the gods - and philosophers have written reams on the subject. But science has had little to say about this ultimate question.
DO YOU REMEMBER THIS OLD QUESTION OF MINE :--
Mohamed El Naschie asked a question in Quantum Physics:
Banach tarski is hardly used as much as should. why ?Banach-Tarski theorem and Cantorian micro space-time
MS El Naschie - Chaos, Solitons & Fractals, 1995 - Elsevier
... Given two solid spheres A and B of different radii, it is possible to decompose them into the same
finite numbers of ... sets and immensely complicated for n>3 that give rise to the strange conclusion
THE ANSWER OF THE PRESENT NEW QUESTION MAY BE VIA THE BANACH TARSKI THEOREMFollowing
- NewDo I include the baseline value of the outcome variable as one of the repeated outcome measures in a Generalised Estimating Equation analysis?
I am doing a Generalised Linear Model analysis(GEE) and need some advice. I am comparing two well-randomised groups for an outcome measured at 5 follow up points, and the only real difference between groups is the baseline value of the outcome variable. I want to know if I should include the baseline measure of this outcome as one of the 'repeated measures' or just use it as a covariate. I suppose my lack of understanding of how GEEs work is the issue here. If it works by comparing the regression lines (over time) between the two groups (and thus the comparison is simply of the gradient of the lines) then it makes perfect sense to include the baseline measure in with the 5 follow up measures. But if there is also some comparison of the absolute magnitudes of the outcome variable at each time point in each group then including the baseline in the repeated measures would surely be a source of bias: the baseline difference could potentially contribute to any conclusion of a difference at follow up (or might eradicate any true difference). So do I include the baseline measure in the 'repeated measures' or do I just include it as a covariate? I'm using SPSS by the way. Thanks in advance!Following
- 2Which is the best material for application in high temperature receiver coating?
Looking for application in solar thermal technology as receiver in Concentrating Solar Thermal (CST) Systems
Pyromark 2500 is the most common material used for central tower CSP systems. A paper surveying its properties is Ho et al (2013) http://dx.doi.org/10.1115/1.4024031.
Lower-temperature systems such as parabolic troughs, with evacuated tube receivers, typically very high-performance selective surface coatings. These coatings are not air-stable however, and depend on the vacuum for their durability.Following
- 99+How would you consider the collapse we are currently entering into?Historians and economists have recently focused on the collapse of economies, societies, cultures, and even civilizations. The ongoing crises seem to be closely intertwined. The diagnostics are clear enough. However, little if at all about space solutions. How do you see this?
Thanks for your comment. And what I was discussing was only the political or economic collapse of empires, and the whole discussion of collapse by environmental events, is a whole other volume, like Jared Diamond's book COLLAPSE,
Or the story of the Indus Valley Civilization that had about five million people living in about 1,000 cities, that disappeared 3,000 years ago so completely, we still do not know where these people came from, or where they went to after they abandoned their cities, or how they lived because we still cannot read their script?
So if we look at the environmental-impacted collapses, say from permanent drought, like the Maya of Central America or the Anasazi of the US Southwest, or the Sabeans of Yemen after their dam broke, that could cause a more immediate abandonment or death of an empire, rather than the slow and natural birth, growth, aging and passing away of a civilization that can take hundreds to many hundreds of years to proceed.Following
- 5What is the difference between descriptive research and experiment research design?
What is the difference between descriptive research and experiment research design?
In addition to answers as already provided, you may be interested to look at the three types of research approaches: exploratory, descriptive and causal. Experimental design may fall under causal research. Please check the following link to a web-text, chapter 1, click on Step 3. Hope it helps.Following
- 3How to write code for POTENTIAL FIELD method in path planning?
Dear madam/ sir , I am working on path planning. I need how to write a code for POTENTIAL FIELD method if you have any code please share me.Mail: [Personal information removed by administrator]
You can use this code http://forum.unity3d.com/threads/ai-influence-maps.145368/
However, for potential fields you will have to use vectors instead of scalar values per cell of the grid.Following
- 2Any 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?
Yes, he said the right thing. If you are not aware of the exact weighing factors, can use AHP.
It depends on the issue you work. if you have contacts with the experts in the field, who is familiar with the study area, you can get the weighting values for each factors you used in the analysis.
- NewHello! can anyone give me the codes for enter spoken words into Matlab?
In need it for my computing projectFollowing
- 2What is the best method of mapping in Arcgis?
I am doing salinity mapping in coastal aquifer. I want to know which is the best method used for mapping...
What actually you want to do with the data? Can you explain little more, then we can put more accurate and clear suggestions.
You can use either the vector (shapefile) based mapping or can interpolate using the raster options ( spatial analyst) in ArcGIS.
If you are taking the point based observation better is the spatial interpolation ( eg. IDW, or Krigging), to get the spatial distribution of salinity over the region. You can use the study area extent as limiting boundary.
Hope this will help you.
- 1Can As2Se3 be deposited onto germanium strip waveguide?
Hi,colleagues. I want to know if As2Se3 (or As2S3) material can be deposited onto germanium strip waveguide? If so, is this process compatible with CMOS process?
Can anybody help answer this question?Following
- NewAny conclusion on judge whether a symmetric matrix with zero diagonal entries is positive definite or not?
Say A=B*B^H (^H means conjugate transition)
C=A - (diagonal of A).
So C is a symmetric matrix which diagonal entries are all 0.
I wondering whether there is any study on how to judge C is positive definite, or not
- 3Which is the correct way to calculate the topographic wetness index with ArcGis?
I need to calculate the wetness index with ArcGis. I know there are a lot of different way to estimate it. I have filled and projected my digital terrain model to obtain (with the hydrology tool) the flow accumulation map. Then I have used the wetness index formula:
Unfortunately I still have negative values.
Can someone help me?
I suggest you to use SAGA -an open source software.
You can see the excellent results of almost all topographic / terrain variables ( morphometric as well).
Finally you can take all the results to ARGIS.
Here the link
- 5What is the effect on the CIC to be determined at different pHs ammonium acetate?
CIC is being determined in soil and clay fraction. First we wash the floor with sodium acetate three times, then three times with alcohol and finally we washed with ammonium acetate to quantify the amount of sodium.
Drs Ghafoor and Dr.Pal,the description given Ms Ronni matches with sodium acetate method of Bower et.al 1952. The same method is available in US salinity laboratory hand book no.60.It also available in many other sources. As for my experience this method works well in neutral to alkaline soils.At pH 8.2 the calcium carbonate in calcareous soils may not interfere with this method. As pointed out by Dr.Pal ,CEC estimation by ammonium acetate method is at pH 7.0 only,not at different pHs.It is well known that in calcareous soils the ammonium acetate dissolves calcium carbonate and leads to over estimation of exchangeable Ca.Recently limed soils may create more problems than agged carbonates. Upto soil pH 7.5 small amounts of lime in soil may not pose problem in CEC estimation.In acid soils ammonium acetate method overestimates the CEC as pH dependent sites are also included in estimation and a separate method is needed for acid soils.In heavy metal polluted soils sodium or ammonium acetate may not be able to replace exchangeable di or trivalent ions .So the CEC is under estimated.In heavy clay soils especially in sodic soils the stirring/shaking and centrifugation with sodium acetate may give some problem.Following
- NewWhat are the possible reasons of getting very low or no transformants during cloning?
Is it okay to heat shock the E. coli competent cells at 45°C for 50 minutes?Following
- NewAre still relevant quite recent views that antiparkinsonian drugs have no clinically significant drug-drug interactions at CYP?
Some data on catechol O-methyltransferase inhibitors and dopamine agonists all refer to in vitro studies of the drugs. As for in vivo situations, for example, a synthetic ergoline dopamine agonist cabergoline has a high affinity for D(2) receptors indicated for use in both early and advanced Parkinson's disease and in hyperprolactinaemic disorders. Following oral administration, peak plasma concentrations of cabergoline are reached within 2-3 hours. Over the 0.5-7mg dose range, cabergoline shows linear pharmacokinetics in healthy adult volunteers and parkinsonian patients. Cabergoline is moderately bound (around 40%) to human plasma proteins in a concentration-independent manner; concomitant administration of highly protein-bound drugs is unlikely to affect its disposition. The absolute bioavailability of cabergoline is unknown. Cabergoline is extensively metabolised by the liver, predominantly via hydrolysis of the acylurea bond of the urea moiety. Cytochrome P450-mediated metabolism appears to be minimal. The major metabolites identified thus far do not contribute to the therapeutic effect of cabergoline. A significant fraction of the administered dose undergoes a first-pass effect. Less than 4% is excreted unchanged in the urine. The elimination half-life of cabergoline estimated from urinary data of healthy subjects ranges between 63 and 109 hours. Mild to moderate renal and hepatic impairment, administration of food and the use of concomitant antiparkinsonian medications, such as levodopa and selegiline, have no effect on the pharmacokinetics of cabergoline.Following
- 20Want to identify these uploaded pictures of fungus ??
Please help me to identify these microscopic fungus pictures. Their scientific name according to their morphology.
- NewWhich of the two culture media is good for the growth of Staphylococcus aureus? The Mannitol Agar or the Tryptic Soy Agar?
I am confuse which of the two culture media is the best for the growth of S. aureus.
Experts, I need your help. :)
Thank you. :)Following
- NewDo you know some free software available for genetic parameter estimation for dummy variables?
For dichotomous variables (0/1) there are some packages available to estimate variance components
Please read the following:
Population Genomics Software
21 novembre 2013 ( dernière mise à jour : 4 avril 2014 )
ABC4F : Approximate Bayesian Computation for F-statistics
A free software that estimates F-statistics using dominant data. The method implemented in ABC4F corrects for the ascertainment biases that characterise AFLP markers. This program is distributed under the terms of the GNU General Public Licence (GPL).
Windows binary : ABC4F.zip
Source code : ABC4F_src.zip
The method is described in the following publication :
Foll, M, M.A. Baumont and O.E. Gaggiotti, 2008. An Approximate Bayesian Computation approach to overcome biases that arise when using AFLP markers to study population structure.Genetics, 179:927-939.
BayeScan : BAYEsian genome SCAN for outliers
Downloads ands informations on BayeScan website
A free software that identifies outlier loci. It’s applicable to both, dominant and codominant data. This program is distributed under the terms of the GNU General Public Licence (GPL).
The method is described in the following publication :
Foll, M and O.E. Gaggiotti, 2008. A genome-scan method to identify selected loci appropriate for both dominant and codominant markers : A Bayesian perspective. Genetics, (in press).
BIMr : Bayesian Inference of imMigration rates
A new Bayesian method to identify the environmental factors that influence recent migration. BIMr is a free software that makes inferences about recent proportions of immigrant genes in subdivided populations and that identifies the environmental factors that are responsible for observed gene flow patterns.
Linux binary : BIMr-linux-i686.tar.gz
Mac OS X binary : BIMr.dmg
Windows binary : BIMr.zip
Source code : BIMr-src.tar.gz
Corresponding instructions are given in themanual.
BIMr is distributed under the terms of the GNU General Public Licence (GPL) and is available for all three major platorms.
Contacts : Pierre Faubet and Oscar Gaggiotti
The method is described in the following publication :
Faubet P. and O.E. Gaggiotti, 2008. A new Bayesian method to identify the environmental factors that influence recent migration. Genetics 178 : 1491–1504.
COLONISE is a user-friendly Microsoft® Windows software for the study of colonisation events in natural populations. It determines the composition of the newly colonised population and makes inferences about the factors that influenced individuals to establish a new population. COLONISE uses a hierarchical Bayesian model to combine multilocus genotype data with demographic and environmental data, and a reversible jump MCMC algorithm to perform posterior density estimations. The software is written in C and C++ for the graphical user interface. It integrates a tool to draw posterior density functions (histogram, running mean, traces, etc.) and to estimate parameters from them (mean, mode, variance, HPDI etc.)
Windows binary : Colonise.zip
This program is distributed under the terms of the GNU General Public Licence (GPL).
The method is described in detail in the following publication :
Gaggiotti, O. E., S. P. Brooks, W. Amos and J. Harwood, 2004 Combining demographic, environmental and genetic data to test hypotheses about colonization events in metapopulations. Molecular Ecology 13 : 811-825.
The software is described in the following computer note :
Foll, M., and O. E. Gaggiotti, 2005 COLONISE : a computer program to study colonization processes in metapopulations. Molecular Ecology Notes 5 : 705-707.
GENBMAPis a user-friendly Microsoft® Windows software for the study of the spatial genetic structure. The method is essentially descriptive, and allows an user to analyze genotypes and geographic coordinates simultaneously through a two dimensional graphical representation. GenBMAP provides a basis for the interpretation of the genetic structure of a population.
Contacts : Alain Cercueil, O. François and S. Manel.
GESTE : GEnetic STructure inference based on genetic and Environmental data
GESTE is a Bayesian method to evaluate the effect that biotic and abiotic environmental factors (geographic distance, language, temperature, altitude, local population sizes, etc.) have on the genetic structure of populations. It can also be used to study spatial population processes, such as range expansions, by simply introducing longitude and latitude as the explanatory variables.
GESTE estimates FST values for each local population and relates them to environmental factors using a generalized linear model. The method requires genetic data from codominant markers (e.g. allozymes, microsatellites, or SNPs) and environmental data specific to each local population. The software is written in C++ and integrates a tool to draw posterior density functions (histogram, running mean, traces, etc.) and to estimate parameters from them (mean, mode, variance, HPDI etc.).
This program is distributed under the terms of the GNU General Public Licence (GPL).
Windows binary : GESTEv2.zip
The method is described in the following article :
Foll, M., and O.E. Gaggiotti, 2006. Identifying the environmental factors that determine the genetic structure of Populations. Genetics 174 : 875-891.
ISIF : In SIlico Fingerprinting
ISIF (In SIlico Fingerprinting) : A free user-friendly software that performs in silico AFLP (can also be applied for DART or RAD).
The program runs under windows and needs the Microsoft .NET Framework version 2.0 (freely available at http://www.microsoft.com/downloads ).
The method and validation of the program is described in the following article :
Paris, M., Bonnes, B., Ficetola, G.F., Poncet, B.N., Despres, L. (2010) Amplified fragment length homoplasy : in silico analysis for model and non-model species. BMC Genomics 11:287.
The manual of utilisation is described in the following chapter :
Paris, M., Despres, L. (2012) In Silico Fingerprinting (ISIF) : A User-Friendly In Silico AFLP Program. In "Data Production and Analysis in Population Genomics" (Bonin A, Pompanon F eds). Methods in Molecular Biology Series, Humana Press. 888:55-64.
Computer program for parentage analysis (2002) Cercueil Alain, Eva Bellemain and Stéphanie Manel, Journal of Heredity, 93 : 458-459).
Contacts : Eva Bellemain and Alain Cercueil
A R script to evaluate AFLP electropherograms for phenotyping and marker selection based on peak height distribution and repeatability using blind controls.
The method is described in the following publication :
Herrmann D., Poncet B. N., Manel S., Rioux D., Gielly L., Taberlet P., Gugerli F (2010) Selection criteria for scoring amplified fragment length polymorphisms (AFLPs) positively affect the reliability of population genetic parameter estimates. Molecular Ecology 53:302-310.
WOMBSOFT linux et Mac
WOMBSOFTis a collection of R functions Wombling-based that analyse individually geo-referenced multilocus genotypes for the inferences of genetic boundaries between populations. The software produces two maps. The first shows the variations in systemic function and the variations in the mean direction of the gradient in the studied area. The second map represents candidate boundary elements that are significant at the chosen level. It can be used with codominant or dominant markers.
2- Program Genes
A Software in the Area of Genetics and Experimental Statistics
Hoping this will be helpful,
- 3What if we measure time difference in the electron double slit experiment ?
My question is about the famous double slit experiment used in Quantum physics. In this experiment, even a single electron is behaving as a wave until hitting the phosphorus plane. It seems that Hitachi have conducted this experiment by firing electron-by-electron.
My question is what would happen if the electron gun is displaced from the middle line so electrons paths get slightly different in length. in this case, electrons passing through different paths should require different time to arrive to the Phosphorus plane. Then by measuring the time difference we can know which path the electron has selected. I know that is is not allowed by Quantum physics, but the question is why?
AKRAM -- SEE ALSO http://www.degruyter.com/view/j/ijnsns.2005.6.2/ijnsns.2005.6.2.95/ijnsns.2005.6.2.95.pngFollowing
- 2Is it allowed to upload papers here, which are already published as articles?
I noted that many researchers upload their articles here on RG. I would like to do the same. But is it allowed to upload papers here, which are already published as articles if you don't have permission by the journals in which they were first published?
Kindly see the attachment and Researchgate links given below:
- NewIs there any other specific technique to identify microglia from mice brain other than Flow cytometry?
I usually look at microglia isolated from mice brain using the standard percol gradient method without using Collagenase/DNAse steps i.e. just meshing the brain with 10 ml syringe plunger and then layering 30% brain cell suspension on 70% percol. This is the way I look for infiltrating lymphocytes (CD45 Hi) and microglia (CD45 Int CD11b+ cells) by Flow cytometry. The method works well for analyzing infiltrating lymphocytes but for microglia, I get the fluctuating data for the mice even within the same group. Is there any other clean and better way to isolate and characterize microglia from mice brain? Waiting for your suggestions.Following
- 7What is the best procedure and condition to prepare hydrazide by reaction of ester and hydrazine?
any one that work before to prepare hydrazid by reaction of ester and hydrazine hydrate can help me that what is the best Procedure and condition to prepare hydrazid by reaction of ester and hydrazine hydrate .
i have acid ethyl ester and i try before :
solvent ester in absolute alcohol and then add hydrazine and reflux it
i Just prefer the hydrazide .. the problem was with hydra zen the reaction need new and fresh hydra zen ... its need = 1 hour reflux and put the round in the freezer
thx # Rokaia Abdullah
# Talaat I. El-Emary
Kirill I. PetkoFollowing