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- Fuzzifier importance in Fuzzy clustering.
I would like to know what is the importance of the fuzzifier parameter in fuzzy clustering algorithms like c-means? I understand that it determines to which level clusters can overlap. However, I see that we should not artificially select a value of fuzzifier as in C-means, because the real overlapping of clusters may be less or more than that value, which may affect the accuracy of the clustering process. So, regardless of C-means algorithm which uses the value of the fuzzifier in its mathematical formula, is fuzzifier in fuzzy clustering really important? Is it recommended that someone uses a clustering algorithm which drops the idea of fuzzifier?
Hello Dania, Please go through these links these may help to you,
- Do you use movies in teaching?
The use of movies provides educators with a valuable tool and means a break to traditional teaching methods.
What do you think about that? Have you ever used movies as a teaching tool? Please, tell us about your opinion and your experiences.
I have used You Tube clips in my undergraduate classes. This source is enthusiastically used by students to explore additional examples on their own.Following
- Does anyone have any experience with membrane protein reconstitution in phospholipid bilayer- choosing lipid mixtures?
My actual task is to incorporate some membranes proteins (multipass, 7TM, singlepass) into liposomes and nanodiscs.
Native membranes are polarized structures with different lipid composition. In liposomes and nanodiscs this state is not possible to obtain so I have to make decision which lipids or lipid mixtures I am going to use as a medium for my proteins.
I wanted to ask if anybody has some experience in protein incorporation into lipid structures.
Do you know any database describing lipid-protein interactions? How do I know If I should use pure lipids or natural extracts an what kind?
First thing that comes to my mind is protein pI. Should I pick negatively charged membrane for proteins with pI>8 and neutral one for acidic proteins ?
I would be grateful for any help.
Our incorporation is for other purposes. We need it for structural studies and phage display. Problem is that I have small amounts of my proteins so it is not possible to test different lipid mixtures. I have to choose them very wisely not to lose my targets.
I have some lipids from Avanti e.g. E.coli polar lipids, egg PC, POPC, DMPC, sphingomyelin, DOPC a probably few more.
I just want to know if there are any general guidelines for choosing lipids.
Let's take an example of bacteriorhodopsin, 7TM protein, pI~5.5. Do you think I can use E.coli polar lipids, which are composed majorly of PE, but also have a lot of negatively charged PG and cardiolipin? Or maybe I should use egg PC with neutral polar groups? I may assume that negatively charged protein will repel negatively charged lipids and it can affect its stability. Did you meet this problem, anyone?Following
- Is HRV an accurate tool to quantify training load in athletes?
In my experience we've found interesting data, especially in soccer players. We are trying to identify HRV changes as a biomarker in the control of weekly training load impact before soccer games.Following
- Could anyone give me the technical specifications for quarantine detection and identification of apple scab( venturia inaequalis)?
In China , apple scab do occur occasionally in a few areas, but we have little experience, want to find the the international standard as a reference, and makes the national standard for quarantine detection and identification of venturia inaequalis.
thanks a lot for your reply. And could you please give me the email of Professor Xiangming Xu and Kent, U.K. - East Malling .
Thanks agian for your help!
Zhengzhou fuit research Inst. of CAASFollowing
- Do you think that employee gender may affect organizational commitment?
Some studies have proved that female employees are more committed to work than male employees, while other studies proved that male employees are more committed. What is your opinion.
I strongly agree @ Monica & J Perriot. In my point of you female employees are more committed their work than male employees.Following
- How can I conjugate a steroid with metal nanoparticles?
How to conjugate or anchor steroid with metal nano particles? Any reference to modify the nano particles surface to conjugate steroids?
Dear Fabrizio Chiodo
Thanks a lot for your answer and references.Following
- When I run the Lee-Strazicich unit root test (two break unit root test), the LS test has no critical values for my little sample, what should I do?
The LS test has the critical values, and they did this simulation with one hundred samples. But my sample size is about fifty, could I still use the LS test's critical values? Or should I do the simulation to get my critical values?
Could anybody tell me that I can use the critical values in which condition? Can I use it when my sample sizes is above 100? Or do the simulation when the sample sizes is below 100? How can I get across the idea of critical values with 100 samples by simulation?
yes, I have read the paper. The empirical research part of this paper, there are about 125 observations, similar to their simulation's sample size. But some paper use this method with only 50 observations, and still use the paper's critical values, is that normal?
- What type of question can be asked from XRD during viva?
Can anybody help me out?
What are the reason for getting background noise in the XRD pattern?Following
- How many cells should be seeded for immunofluorescence?
Which one is better to be used chamber slides or coverslip?
Although the dilutions vary for primary antibody or secondary antibody as company differs Any suggestions regarding dilutions Sherry.What i found in literature is 1:100 primary and 1:50 secondary.Following
- Cluster Shape.
What makes some clustering algorithms capable of detecting non convex or arbitrary cluster shapes? For example, K-means cannot detect arbitrary cluster shapes, while other algorithms can. What is the reason behind that?
Thanks for the question, I am currently working on clustering algorithms myself.
Identifying clusters of arbitrary shapes require information regarding pairwise connectivity between each point in the dataset. The k-means do not cluster based on this measure hence it doesn't cluster non-convex dataset.
The k-means defines a cluster based on its distribution around a point - rather a globular area around its prototypes. while this allows it to have a rather cheap cost in both time and memory, k-means sacrificed the computation for pairwise distances between point, which limits it to find convex clusters.
One approach to extend the k-means ability to non-convex clusters is to use kernel method, but the kernel k-means has been shown to closely resemble the spectral graph, and it is not cheap either.
In order to cluster non-convex shapes, one needs to measure the distance (proximity) between each point in the dataset. Graph methods are rather expensive for this reason and therefore are not as scalable as k-means.
Recently there are approaches using consensus clustering / ensemble clustering. They use multiple runs of partitional algorithms (e.g. k-means) and graph / linkage clustering methods. This way, k-means can be used to cluster non-convex dataset. If you're interested you can read more on ensemble clustering.Following
- Is your country at a risk from transboundary pollution?
Transboundary pollution (pollution that crosses the boundaries of a nation) is the pollution that originates in one country but is able to cause damage in another country’s environment, by crossing borders. Pollutants can travel through pathways such as wind, dust particles, flow of rivers, ocean currents, and via seabirds. The long-range transport of air pollution has been recognized as an important factor affecting health of ecosystems and human. Transboundary flows of pollutants occur between states of a country, between closest neighbouring countries, as well as between continents.
Persistent organic pollutants (POPs) (e.g. dioxins, furans, PCBs, and some organochlorine pesticides) can be transported over long distances in the atmosphere, resulting in widespread distribution across the earth, including regions where they have never been used. Coal-fired and oil-fired power stations, and mobile sources, such as cars, ships and aircraft emit a complex mixture of pollutants, including sulphur dioxide and nitrogen oxides (the precursors to acid rain). These air pollutants can also be transported over hundreds or even thousands of kilometres, for example, it is reported that much of the pollution emitted in the UK travels across the North Sea and is deposited in Scandinavia (as acid rain). The Arctic is supposed to be a pristine environment, however, in recent years; several types of contamination have been found in the arctic (e.g. heavy metals, POPs, radioactive) which are transported to the Arctic by winds, rivers and ocean currents. Smoke haze (dust, smoke and other dry particles) due to land clearing and ‘slash and burn’ agricultural practices in Indonesia has been a perennial problem in the southern ASEAN region causing much environmental damage in Singapore, Malaysia, Brunei, and Southern Thailand.
Owing to their toxicity, the POPs can pose a threat to humans and the environment (POPs bioaccumulate in human and animal tissue, in food chains, also an endocrine disruptors). Acid rain causes acidification of lakes and streams and contributes to the damage of trees at high elevations and many sensitive forest soils. Acid rain accelerates the decay of building materials and paints, including irreplaceable buildings, statues, and sculptures that are part of nation's cultural heritage. Sulfur dioxide and nitrogen oxide and their particulate matter derivatives—sulfates and nitrates—contribute to visibility degradation and harm public health. Air pollution from open burning can cause serious health problems and damage the environment. Children, the elderly and those with existing health problems are particularly vulnerable to smoke from open burning.
To control the spread of transboundary pollution the United Nations Economic Commission for Europe (UNECE) implemented the Convention on Long-Range Transboundary Pollution (1979).The Minamata Convention on Mercury is an international treaty designed to protect human health and the environment from anthropogenic emissions and releases of mercury and mercury compounds. The Stockholm Convention on Persistent Organic Pollutants is an international environmental treaty, signed in 2001 and effective from May 2004, that aims to eliminate or restrict the production and use of persistent organic pollutants (POPs).The ASEAN Agreement on Transboundary Haze Pollution is a legally binding environmental agreement signed in 2002 by all ASEAN nations to reduce haze in south-East Asia
Question: Is your country at a risk from transboundary pollution?
(Any weblinks or references relevant to transboundary pollution or any regional or international treaties to reduce transboundary pollution would be much appreciated)
You have identified a very important global transboundary pollutant-plastic. Plastic in the oceans caused killing of birds and fish. In addition, fish ingesting plastic may cause accumulation of toxins and thereby pose a risk to human consumers from consumption of seafood contaminated with plastic!Following
- What parameters should be checked in sensitive analysis for supply chain network design?
When do we need to do sensitive analysis and what relationship and parameters should be check in supply chain network design?
when we have a input parameter with variety options ,do we need to check its affect?,also sometimes I have seen some researchers check the relation between some other parameters in sensitive analysis.Following
- How do I pair two different survey instruments in SPSS to run descriptives and correlations analysis?
I am a senior student at the University of Aruba. Consequently, I am writing my thesis about the impact of leadership behaviors on trust from the subordinate perspective and how that trust relationship in turn, influences the subordinate citizenship behaviors from the supervisors perspective. Therefore I have developed two different survey instruments. My question is as follows: for the data analysis, what are the different ways to pair the two surveys in SPSS for descriptives and correlations analysis?Following
- Could you explain mouse yolk sac formation, maturation and degradation during embryogenesis? I need to know more about the yolk sac, but the papers that I have found talk about haematopoiesis or macrophage origin, and I want to know about the timing/factors involved in yolk sac formation/biology.
Check out the following BMC Dev Bio paper, even though it focuses on amnion formation. Movie, too!
Amnion formation in the mouse embryo: the single amniochorionic fold model
Paulo NG Pereira13, Mariya P Dobreva13, Liz Graham4, Danny Huylebroeck23, Kirstie A Lawson4 and AN Zwijsen
- When quantitative and qualitative results does not match and is contradictory, what to do in a mix method research design?
What can be good strategy when the quantitative and qualitative results differ in mix-method settings? Keep it in the same article or separate the results and prepare two different manuscript for different outlets?
Muhammad - I do feel for your plight. Of the two mixed-method approaches i.e 'simultaneous' and 'sequential', it sounds like you have opted for the wrong approach. If you had chosen sequential, which is usually the 'safer option', then you would have avoided this. Ethically-speaking, if you started, conducted and got approval for this study as a mixed-methods approach - then you are more obliged to publish it as such within a single publication. On the other hand, in my mind, it is not wrong to publish findings separately - as long as each article identifies that 'it is part of a wider mixed-methods' study - but that 'these particular findings are more appropriate for this journal'.Following
- Who is your favorite character in world history and why? There are many persons who made or change some aspect of the world history
@Nageswara Rao Posinasetti has a good idea in pointing to a number of persons that he considers important characters in world history. I also think that there a number of characters in world history that tower above the rest in one way or another. Here are some of my choices, limited to the last 130 years:
> Som Naimpally because he is a great teacher as well as a great mathematician. See, for example, S.A. Naimpally, Proximity Spaces, Cambidge University Press, 1971: http://ebooks.cambridge.org/ebook.jsf?bid=CBO9780511569364
> Anna DiConcilio because she is also a great teacher and great mathematician. See, for example, A. DiConcilio, C. Guadagni, Bornological convergences and local proximity spaces, Topology and Applications 173, 2014, 294-307:
> Gerald Beer, because of his ground-breaking work on convex sets and closed sets, epitomised by his book Topologies on Closed and Closed Convex Sets, Kluwer, 1993: http://www.amazon.com/Topologies-Closed-Convex-Mathematics-Applications/dp/0792325311
> Felix Hausdorff, who introduced vector spaces, important distance measures, set theory (as we know it nowadays), and topology, all in his 1914 Mengenlehre book. See F. Hausdorff, Grundzuge der Mengenlehre, Leipzig Viet, 1914:
> Paul Halmos, who introduced finite-dimensional vector spaces and made a number of important discoveries concerning Hilbert spaces. See, for example:
P.R. Halmos, Finite-Dimensional Vector Spaces, Springer, 1958:
> R.R. Phelps, who introduced proximinal sets and a number of important results concerning nearest point sets that are convex sets in vector spaces. See, for example, R.R. Phelps, A representation theorem for bounded convex sets, Proceedings Amer. Math. Soc., 1960:
> V.A. Efremovich, who, during the early 1930s, introduced proximity spaces in the context of what he called infinitesimal geometry and giving axiomatic approach to the study of the nearness and remoteness of sets.
> Henri Poincare, who, starting in 1895, informally introduced tolerance spaces and paved the way for a formal view of similarity and suggested an approach to describing tolerance classes in a physical continuum.
There are many others.Following
- Is anyone interested in exploring the perception of fragility? The market of fine products sometimes offers extremely fragile items. Fragility can be observed not only in sculptures but in utilitarian objects as well, such as wine glasses. The one shown here is hand made and needs extreme care to wash. This is impractical. Why do people want impractical objects, when there are durable ones?
As a person who senses and notices the various qualities of objects, please explain if fragility can offer aesthetic appeal to you. Do you perhaps respond to fragile things as something to be careful with, or as having a particular appeal, or to care for?
I’m interested in personal opinions only. There is no need to guide me to any literature.
• Associated concepts: Airy, Diaphanous, Ethereal, Light, Soft, Transparent, Delicate, Tenuous.
• Some Examples: china , porcelain , crystal, tiny birds, newborn baby, a dandelion (the round puff) , silk, flower, insect wings.
Nelson, Are you telling me that my ideas will inspire a publication when you say?
"If I were to write a monograph about him, it could easily bear the title, "Silva or the perception of the fragile."
"Before reading your genial thread, I never realized this.
if I had a Ph.D. candidate right now looking for a thesis topic, I would recommend his perception of fragility."
I thank the praise, if but if my research (Exploring the Perception of Fragility) inspires a publication the idea must be credited to my name and my RG question. :)))))Following
- Does anyone else have problems growing NK92-MI cells after freezing?
I'm a grad student in biochemistry and now trying to grow NK92-MI cells from ATCC but they all die by day 3. Cells were frozen in 90%FBS/10%DMSO at a cell density of 2x10-6, thawed and seeded at 2.5x10-5 cells/ml following ATCC protocol. I'm using alfa MEM supplemented with L-glutamine, 2-mercaptoetanol, folic acid, inositol, 12.5% HS and 12.5% FBS.
I have some questions...
1. Should I feed at day 2 or rather let them settle after thawing and feed at day 3?
2. I'm spinning down to remove all DMSO after thawing and resuspending with fresh media to seed. Should I not spin down?
3. Is there any other media they grow better with?
4. What growing rate should I expect?
Thank you in advance ,
- What butterly is this?
Can an entomologist please tell me what species of butterfly this is?
This is definitely a European hawk moth (Sphingidae), Deilephila elpenor known in English as the Elephant Hawk Moth. The "elephant" name derives from the extraordinary appearance of the larva (it is actually a snake-mimic) but naturalists in Britain do sometimes refer to the moth as the "pink elephant" (this is a joke: there is a tradition in Britain that alcholics who are suffering from delirium tremens suffer hallucinations in which they see pink elephants). The species is common through much of Britain, and is spreading northwards as the result of global warming.
So I agree entirely with Pavel Jakubek.Following
- What method is employed to check the structure/molecule stability?
Recently I was encountered with a problem where structure shown in figure is not able to get converted to any product. May be possibly due to its resonance effect or any other effect between the neighboring groups (cyano and amino). Neither cyano group is reactive nor amino group is reactive. Do I have any alternative option to prove this hypothesis via any computational software/webserver/informatics/molecular modeling, that the concern molecule is highly stable or inert for any reaction Even I don't know which software is better for these calculations.
Any other relevant information regarding the query will be helpful.
Please suggest me a way to solve this problem.
Dear Gergely Juhasz,
The software links you have provided were not working. How to get them kindly send me other different links to download.
waiting for your possible reply.......Following
Primordial germinal cells (PGCs) do not have the history of origin and migration. Some literature's said PGCs are arise from mesoderm, other literature said PGCs from ectoderm or endoderm or embryogenesis.
From Saitou et al., Development, 2012 on mouse PGCs:
"PGC specification takes place in the most proximal epiblast in response to bone morphogenetic protein (BMP) signalling from the extra-embryonic ectoderm at ∼E6.0 (Lawson et al., 1999) (Fig. 2A,B). At this stage, epiblast cells are still pluripotent but are being propelled towards somatic fates and are in the process of losing their pluripotency (Kurimoto et al., 2008)."
Today's standards for tracking stem cell fate in organismal systems are higher than simply a molecular one. We impose standards on what we produce. So, why don't we have common standards?
For example, should we want to track cell behaviors and know molecular information at the same time?Following
- From powder xrd data, it is possible to find unit cell parameters?
To find a,b,c values and angle for the compound using powder xrd graph
thanks for your link. I have got it downloaded. can you suggest me any manual or method to be followed to calculate the lattice parameters. I have one more question to you, can we caluclate structural parameters like bond length and bond angles using powder xrd? kindly reply
- Does psychological ownership affect employee productivity?
The actual legal ownership of employees can lead to better productivity. What about the psychological ownership?
If I understand literally the term owning properly, no person or organization should own a person of knowledge and skill or professional, psychologically or legally. Owning something is bound to do anything the owner wants on the owned according to the social definition and meaning of owning. But that is not what the relationship between an employee and an employer is. It is a relationship of mutual benefits - the employee offers his/her knowledge and professional skills and the employer pays for the service received. The employee does not own the employer psychologically or otherwise for the lack of knowledge and skill the employer has and seeking the skills of the employee, likewise the employer does not own any thing of the employee as well, unless the term has a different contextual meaning in the management sphere.
I propose that learnt and scientific communities should either use correct words of science with no ambiguity or should create our own words if the words available are wrong for contemporary usage due to connections to bad past events.
On time I heard Stephen Hawking (physicist and cosmologist ) talking about the cosmos and the possible things out there. He went on to say that we humans should go out and colonize galactic places and one day live there. I do like his scientific views and the possibilities regarding the outer universe but the term he used 'colonize" is something which has bad connotations in our world of earthly humans.
Assume as he wished, we went out there and landed in a beautiful and livable galactic place with a banner to colonize, but the inhabitants of that place are to be more advanced in every aspect (science, technology and their deep knowledge and understanding of the universe) and want to cooperate with us and help us adapt their places and start to teach us what their language, science and technology are and their understanding of the universe. But earthly humans landed there with a banner of searching for a colony to colonize and by the time they discovered the meaning of what a colony and colonize are, they will be outraged, although the earthly humans are inferior in current civilizations and understanding of the universe to list the few. Will they be happy then ?Following
- Does anyone have experience in Action Research Validity, Reliability & Generalisabilty?
These 3 issues are the major criticisms that AR faces in comparison with traditional research methodologies. What is your opinion about it?
Thanks Doreen - I like your spin on 'narrative creation'. Michael - I agree with your take on AR being 'practical'. Action research 'enjoys' the unenviable task of being 'difficult to locate' in the research world. Many people mistakenly cluster it under the qualitative paradigm - even if most of the study may be of a qualitative design. This, to me, is purely out of ignorance or comes from those with rigid, positivist 'blinkers' on - who cannot move beyond the fact that 'if it is not entirely quantitative - then it cannot be quantitative'. I personally look to the 'neutral ground' and classify it as a 'mixed-methods' and/or critical 'emancipatory' approach. For those that view it this way, AR may be viewed as a philosophical approach, and some even refer to it as the 'third paradigm'.Following
- Where can I find the Vermunt's Inventory of Learning Styles (ILS) (English Version) for my Research? There are many style inventories, but I am interested in learning style inventory, developed by Vermunt, specifically for higher education students. I want to check its cross cultural validity in south Asia.and utilize it in individual research.
thanks Stella Maris Vazquez
my email is email@example.com
- Why women have made so few major discoveries in theoretical physics in last 50 years?
Over last 5 decades women have made enormous progress in many fields of sciences such as biological sciences, chemistry, medicine, dentistry and veterinary science. In most of these fields women's college graduation rates now exceed men, sometimes by 2 to 1. However women's progress in physics in general and theoretical physics in particular has been rather modest. Here in US only about 20% of the PhD degrees in physics are awarded to women and almost all of these are in experimental fields.
This lopsided nature of women's achievement in physics comes into very sharp focus if one looks at the major discoveries - recognized by the awarding of Nobel prize - in last half century. No woman has won a Nobel prize in physics since 1963, even as the number of women college graduates have increased enormously since then in almost every field of science.
What is the reason for this phenomenon? Why have women completely failed to take their rightful place alongside men in theoretical physics?
I have to come to a conclusion that should have been blindingly obvious to me from the start - although you have all the external trappings of a scientist with a PhD etc, you are not really equipped with that most important characteristic needed in a scientist - an open mind. Your mind is completely closed against any argument or reason not familiar to you or outside your comfort level.
So it would be utterly pointless to carry on this debate any longer. Please do not bother to share any more of your Political Correct thoughts with me any more on this thread. It'll be a complete waste of time for me to either read them or respond to them
Let's move on. I am sure there are plenty of threads here on ResearchGate that could benefit enormously from your very peculiar way of looking at the world. I am sure my loss would be a great gain for other threads. By the way I would be watching your progress through the world of theoretical physics and I would be very curious to see what major discovery you are able to make, handicapped as you so obviously are, with a completely closed mind!!!
Guten tag herr Doktor.Following