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- 1What is the best subcellular fractionation protocol for suspension cells like human AML cell lines?
I am working with human AML cell lines and need to find out the best cellular fractionation protocol for these kind of cells
Check the references to these papers if they help you:Following
- 5How do I recognize mitochondrial swelling?
I am evaluating the anticancer effect of natural products from plants against breast cancer cells. One of our compound induces cytoplasmic vacuoles. I performed immunofluorescence staining using calnexin antibody to observe ER swelling. The result showed that the vacuoles are originated from ER. But, I need to detect whether mitochondrial swelling is also there or not. To analyse this, I stained cells with Mito-tracker red dye and observed under fluorescent microscope. The thing is I couldnt differentiate the normal and swollen mitochondria. It would be much thankful if someone suggest me any tips for the same.
The attached article could may be help you.
- 1Co-transfecting plasmids - how much transfection reagent to use?
I am co-transfecting NIH3T3 cells with two plasmids (rasV12 mutant + gene of interest) for a transformation assay. My question is: how much reagent (FuGENE HD) should I use? I typically use a 3:1 reagent:DNA ratio for single transfections. But as I am adding twice the amount of DNA in total, should I use a 3:1 ratio for only one plasmid or both plasmids? Out of situations A and B below, which would you recommend?
Situation A: rasV12 (1 ug) + Gene X (1 ug) = 3 ul FuGENE HD
Situation B: rasV12 (1 ug) + Gene X (1 ug) = 6 ul FuGENE HD
I would recommend B. If you use a 3:1 ratio (reagent:DNA) then it is 3 times the amount of transfection reagent per total amount of DNA.
- 6Equivalence relation in TU gamesHow do you define an equivalence relation over the set of imputations in a TU game?
Thanks for this answer.
Is there any research that link Nash equilibrium to cooperative games? I am interested in the topic.
The idea I had about the equivalence relation was to setup a solution concept in that framework based on the following Shenoy's (1980) idea : during the bargaining process, "a player who makes a proposal should not cooperate in any effort to defeat his proposal"Following
- 4Which buffer or reagent should I use for harvesting avain macrophages after 2 or 3 days of culture (so very adherent cells) ?
After 2 or 3 days of culture, I didn't succeed in harvesting live monocytes/macrophages without any compound adding ?
I thought that Trypsin will be too agressuive for my cells, Is there other agents for cells detachment ?
Make sure to use non-tissue culture-treated plates while culturing your cells if you're not already, then the removal should be much easier.Following
- 3Is there a way in which we can extract the mathematical model equations from process modelling software like Aspen Plus and Aspen Hysys?
Is there a way in which we can extract the mathematical model equations from process modelling software like Aspen Plus and Aspen Hysys.
The equations may be the differential equations that define the system
they are MESH (mass energy summation &energy balance equations). based on my low knowledge of process simulators (hysys), no such way is existed for simple users to see the equations. in the higher versions, i do not know.Following
- 1While making of mounts for EPMA, my epoxy is getting lodged with SiC powder during grinding. Is there a way to avoid that?
SiC is getting lodged in the epoxy mount and the sample. I wanted to know if the same effect of thinning the epoxy to expose the samples can be achieved by some other method.
My first impression is that the epoxy mount has not completely cured or that the epoxy itself may be old or contaminated. I have made thousands of epoxy mounts and at times one will not cure completely. I blamed this on incomplete mixing before pouring. For critical applications, it is best to do a trial mount to make sure the epoxy cures completely. Another cause of SiC particles embedding in the epoxy mount is excessive pressure and/or too coarse of SiC paper during grinding. You do not state whether the sample is metallic or non metallic. For critical applications I have started with very light pressure 320 grit paper and then to 400 and then 600 grit. From there its diamond and 0.05 um alumina.
Is your epoxy room temp curable or does it require some moderate heat to cure? It can make a difference in curing results. Mixing the epoxy under a heat lamp can help in complete homogeneous product. Maybe you should try a new batch of epoxy to see if it cures better. If you have any further questions, you can contact me at email@example.com
- 4How a perturbation can be identified during the manufacturing scheduling process ?
I would like to know, the practical automated tools or approaches used to identify the presence of disturbances (machine breakdown, late arrival of tasks ....) during the manufacturing process ?
I have been working in wide range of technology in the cereal processing field from the manual control up PLC and remote control .
when we were working manually we record the down time and the root cause which machine of the system. at the end of the month we report and analyse the collected data. to be considered in the maintenance schedule
the old automated control system is connected with a PC which calculates the down time some of the wok is completed as described above
in the PLC any single machine has its own history of breaj downs , maintamance schedule and description of maintenance process...... etc
if understand the question
- NewMicrobiota-gut-brain axis, biodiversity, affect regulation and social neuroscience -- some hypothetical implications. Any critiques?
I'm very interested in the assertion that human homeostasis has to be understood within the multi-scale social and ecological (and chronobiological and cultural) contexts within which we're embedded. Here's one attempt at drawing conclusions from a constellation of articles. Feedback would be much appreciated.
- Increasing evidence suggests that ecological biodiversity is essential to microbiome diversity and health: Logan, A. C. (2015). Dysbiotic drift: mental health, environmental grey space, and microbiota. Journal of physiological anthropology, 34(1), 1. also: Logan, A. C., Jacka, F. N., & Prescott, S. L. (2016). Immune-Microbiota Interactions: Dysbiosis as a Global Health Issue. Current allergy and asthma reports, 16(2), 1-9.
- Microbiome-Gut-brain axis communication is essential to physiological health and has also been demonstrated to play a key role in mental health: Dinan, T. G., Stilling, R. M., Stanton, C., & Cryan, J. F. (2015). Collective unconscious: how gut microbes shape human behavior. Journal of psychiatric research, 63, 1-9.
- It is fairly well-accepted that the vagus nerve is a primary channel of gut-brain axis communication: Forsythe, P., Bienenstock, J., & Kunze, W. A. (2014). Vagal pathways for microbiome-brain-gut axis communication. In Microbial Endocrinology: The Microbiota-Gut-Brain Axis in Health and Disease (pp. 115-133). Springer New York. (Though other gut-brain pathways operate in parallel - see: "Collective Unconscious" article.)
- The vagus nerve is also believed to have played a critical role in the evolution of social relationships and interpersonal co-regulatory strategies: Porges, S. W., & Furman, S. A. (2011). The early development of the autonomic nervous system provides a neural platform for social behaviour: A polyvagal perspective. Infant and Child Development, 20(1), 106-118.
- A recent article suggests social proximity has microbiota advantages, which confer energetic and immune benefits: Stilling, R. M., Bordenstein, S. R., Dinan, T. G., & Cryan, J. F. (2014). Friends with social benefits: host-microbe interactions as a driver of brain evolution and development. Front Cell Infect Microbiol, 4, 147.
- Research on Social Baseline Theory offers evidence that energy conservation and energy homeostasis are also among key benefits conferred by social proximity, whereas social isolation, conversely, causes stress which results in higher consumption of energy: Ein-Dor, T., Coan, J. A., Reizer, A., Gross, E. B., Dahan, D., Wegener, M. A., ... & Zohar, A. H. (2015). Sugarcoated isolation: evidence that social avoidance is linked to higher basal glucose levels and higher consumption of glucose. Frontiers in psychology, 6.
- Recent research demonstrates that energy homeostasis is mediated by the gut-brain axis and influenced by microbiota: Bauer, P. V., Hamr, S. C., & Duca, F. A. (2015). Regulation of energy balance by a gut–brain axis and involvement of the gut microbiota. Cellular and Molecular Life Sciences, 1-19.
- There is also evidence that metabolic homeostasis is also mediated in the brain: Steinbusch, L., Labouèbe, G., & Thorens, B. (2015). Brain glucose sensing in homeostatic and hedonic regulation. Trends in Endocrinology & Metabolism, 26(9), 455-466.
- Another recent article demonstrates the reciprocal adverse effects of social stress on the microbiome, which also negatively impacts health: Bharwani, A., Mian, M. F., Foster, J. A., Surette, M. G., Bienenstock, J., & Forsythe, P. (2016). Structural & functional consequences of chronic psychosocial stress on the microbiome & host. Psychoneuroendocrinology, 63, 217-227.
Some possible conclusions:
- The microbiome-gut-brain axis has to be understood as embedded within a social and ecological context.
- Ecological stress (e.g. loss of biodiversity) and social stress (e.g. isolation) both adversely affect microbiome health, which has reciprocal adverse effects on both biological and psychological homeostasis.
- Affect regulation and gut-brain axis regulation share common neural pathways and may have co-evolved.
- The microbiome-gut-brain axis may play a larger role in the homeostatic regulation of social relationships that is currently understood.
Thoughts? (Note: this post does not address the chronobio aspects of these interactions, but circadian rhythms also play a mighty role in the above. See also: https://www.researchgate.net/post/What_are_the_multi-scale_links_between_homeostasis_energy_conservation_entrainment_well-being)
Your feedback would be much appreciated. Thank you.
- 1How to calculate selectivity index without % cell inhibition and IC50 ?
How to calculate selectivity index without % cell inhibition and IC50 ?
Well, you need two, ideally parellel, dose-response curves. It's really best to use summary statistics such as IC50s for the selectivity index. You don't necessarily need to use the IC50 if you have plateaueffects or the like that make it difficult to estimate, an IC 10 might also work.
If you can't fit a proper simoidal curve you could also estimate from any linear parallel part of the two curves.Following
- 2Can anyone suggest possible solutions for cell culture contamination problem?
We seem to have a very serious problem in our cell culture lab. Lately, we haven't been able to culture cells due to contamination by bacteria. The cells are thawed in one day and the next day, although cells are apparently ok, there are already some bacteria in solution. In two days we have a cloudy medium. We always throw away all contaminated flasks and also medium and plastics that were used at the same time the contaminated cells were in culture. Everything else, including incubator and flow chambers were sterilized before thawing new cells. All the protocols were revised to assure aseptic technique and only experienced workers are handling the cells. Initially, we thought there was a contamination problem with our stock, but it seems that no matter which cell line we use, we always get contamination. This has never happened before in our lab.
Can you give me some advice of how to handle this situation? Is there anything else we should be doing?Thank you for your help! We only have bacterial contamination. We are now trying to narrow down the hypothesis for the source.Following
- 1Necropsy protocols for terrestrial tetrapods?
I am looking for published necropsy protocols on model terrestrial tetrapod species (mammal, bird, reptile).
I am also looking for literature on the scientific use of necropsy data in conservation or general ecology.
Any info out there?
Please see for necropsy of birds:
AVIAN NECROPSY MANUAL FOR BIOLOGISTS IN REMOTE REFUGES
BY THIERRY M. WORK, DVM
U. S. GEOLOGICAL SURVEY NATIONAL WILDLIFE HEALTH CENTER
HAWAII FIELD STATION http://www.nwhc.usgs.gov/hfs/Globals/Products/Sea%20bird%20manual%20english.pdfFollowing
- NewWhen the significant differences (P value less 0.05) should be consider as clinical important (seriously) ?
Are there certain factors could make the statistical significant ( p value less than 0.05) clinically important as larger sample size or randomized controlled clinical studies?Following
- 1What is the species of this gastropod found from near an estuary mouth?
Recently a flood occurred in a city (India) which is located near an estuary. Will this species be pure terrestrial gastropods, estuarine gastropods or marine gastropods. I am confused totally. But I found from an estuary mouth without meat (empty shell).
Looks like a frreshwater PLANORBIDAE speces, but i´m not so shure because of the caracteristics of the specimes, we need more details on this things... (I could say is Planorbula cf. armigera (... but it´s not shure))Following
- 2How would a therapist utilize Motivational Interviewing with a client with substance use problems when the therapist has to play dual roles?
Dual role- Therapist abiding by the spirit of MI at the same time being on a multi-disciplinary team that confrontation is used frequently to point out substance use.
I think, and it´s my idea, based in many years of working in teams and with substance abuse clients, that de rules of the multidisciplinary team must be followed and elicitated when it´s needed, so if you have to confrontate with the client you do it.
In the other hand, like opening a parenthesis, you go ahead wtih MI goals.
As you asume, it´s a Dual Role you have to play, one as MI Therapist, the other as part of a team.
- 4Any articles or researches about interaction in kindergarten?
I want to stimulate the interaction between children with language problems during play. Searching for teacherskills to stimulate interaction during playtime in kindergarten (4-6 yrs old)
You can look into IDP Website. IDP -Persons Project - Children and Childhood. Link attached.Following
- NewHow can I get the moment at the top of the steel section in a composite beam??
How can I get the moment at the top of the steel section in a composite beam??Following
- 2How frequent is coexistance of rheumatoid arthritis and psoroasis?
how frequent are the existence of RA and psoriasis. Is HCQS or hydroxychloroquine justified in the condition?
I think you are asking for the frequency of coexistence of true rheumatoid arthritis with psoriasis, rather than psoriatic arthropathy? There may be literature on this but the problem is that ascertaining the existence of true RA in the presence of psoriasis is not straightforward. Rheumatoid factors and ACPA occur in a small percentage of normals so could occur alongside psoriatic arthropathy.
The only time I have been convinced that I knew that an arthritis was true RA in the presence of psoriasis was in a case with typical rheumatoid nodulosis and RF. I only saw the one case in thirty odd years.
In practical terms relating to hydroxychloroquine, I think you are entitled to go on probabilities. If an inflammatory arthritis is associated with RF and or ACPA and does not have DIP involvement then if you feel hydroxychloroquine is a reasonable choice for RA (I was never very convinced) then it is probably still reasonable if the patient also has psoriasis. Without autoantibodies or nodules the chances must be that you are dealing with psoriatic arthropathy and I know of no theoretical or practical evidence for hydroxychloroquine being useful there.Following
- 4Which borer diatmeter is suitable for obtaining tree cores (minimally intrusive) conaining enough sap water for stable isotope extraction?
I want to identify tree water sources in selected trees over an entire growing season, preferably monitoring the same trees. As I will not have access to suberized branches in most cases, I'm considering to take multiple cores from a single trunk (up to 5 times). Unfortunately, this method is rather intrusive, and hence I'd like to use the smallest borer diameter possible to allow extraction (via cryogenic vacuum distillation) of an adequate amount of sap water, while keeping damage at a minimum.
I'd appreciate any comments on or experience with repeated trunk sampling (effects on sap flow, mortality) and which borer and coring depths can lead to adequate results.
Thanks in advance.
Thank you all for your input - much appreciated. I've decided on getting a large diameter (12 mm). I will hopefully be able to test short-term effects of repeated coring before starting the field season.Following
- NewIs there a relationship between verbal reasoning test outcome and language skill of the mother?
Could anyone advise if there is literature on the relationship between child’s verbal reasoning score and the language ability of the primary carer (mother) at the age of 11 years old? The mother is not a native speaker of the language in which she communicates with the child (English) and in which the verbal reasoning test is taken by the child. Thank you!Following
- 1Does someone who had worked with vectors to analyse nutrimental status in plants know if there is a software to create this kind of graphs?
I would like to draw the vector graphic according to the metodology descrited by Haase and Rose, 1995 (Vector analysis and its use for interpreting plant nutrient shifts...). Thanks.
Graphical vector analysis is available in freeware r-software.Following
- 1Dielectric constant from complex impedance spectroscopy??
i have been performed complex impedance spectroscopy and want to know that how i can find dielectric constant (real and imaginary parts) from impedance data??... what is the method to find dielectric constant from impedance data?
Have you tried to convert impedance to dielectric? if not, try using E = 1/(jwZ), w is radial frequency. For more help, I suggest looking up Prof. A. Lasia's "electrochemical impedance spectroscopy and applications" I think it is available via research gate.Following
- NewIs there anything known about the properties in cis and trans polymers?
I'm doing a research on sinapinic acid. Apparently there is something strange in the DSC results. It rises then is it flat and then rises again more. There are also some signs by HPLC. The problem is I can't find a lot about cis en trans in polymers.Following
- NewWhat is the stable orientation for CuO ?
I need to create CuO surface for which the CuO unit cell is need to be cleaved along stable orientation.Following
- 53Is there Godel's Incompleteness Theorem in Physics like in Mathematics?
The holy grail of Physics is the Unification Theory called by Weinberg as the "Final Theory". When finally discovered, perhaps it can:
1. Unify all fundamental forces in nature.
2. Explain the Hierarchy Problem
3. Explain all Cosmological Problems
5. Gives us the right Quantum Interpretation
but can such theory derive all fundamental dimensionless constants in nature out of pure number and explain the true nature of time?
However, as you see by some previous posts (e.g., Ludmila Pozhar and K.Kassner), your forcing to distinguish between language and propositional calculus (or formal logic) is non well accepted.
Furthermore, when one has a mathematic physical theory we get a structure endowed by a PDE. Then with respect to this structure one can define a (formal) logic and many important aspects of this theory can be obtained by considering this logic. This means that in a structure one can identify a logic structure.
Therefore, your claim:
' I think we should distinguish logic structure from the structure under consideration...'
is correct, but they can be related.
By conclusion to mathematic physical theories we can apply Goedel's incompleteness theorems in extended sense without any trouble on possible equivocations.
- 1Does anyone know of instruments to measure near and far transfer in learning?
Do any such tests exist?
I taught Maths and Science to Grade 10 boys. One morning in the pink-walled Maths classroom I taught simplification of equations by dividing by common factors. The boys understood this and were able to do the exercises.
I had the same boys in the following period without a break. This was a Science lesson in the blue-walled Science classroom. I wrote a chemical reaction on the board and asked the boys to simplify. They could not do so. When I hinted to them that I had just taught them how in the previous period, the boys howled out: “But Sir, you can't do that, that's Maths”!
Did the boys have to walk far? No. They were physically close, adjacent and had walked about 5 metres.
Did these boys have time to forget? No. It took them 1 minute to reseat. They were temporally close.
Did the different colour of the walls influence the boys negatively? No. They were both pastel shades.
In spite of the nearness in space, time and psychology, why did transfer of learning not occur? I thus doubt that there is such a thing as near and far learning or that the changeover point could ever be quantified.Following
- 3Does anyone has references (besides designing interactions book) about the technique 'guided fantasy', by Tim Mott and Larry Tesler from the 70s?
I have been interested in this technique for a deeper understanding of the mental model of graphic designers and managing procedures of their studio management, but all descriptions of the technique I have found are resumed in Bill Moggridge's book "designing interactions"
Thank you Alma Rose Snyder for your interest in my question. This technique that has the same name is different. It focus on education, creativity stimuli and psychologic recovery. This is not what I am looking for.
The technique invented 1973 by Larry Tesler and Tim Mott were used for user experience investigation in technology innovation situations. It is related to user research, mental models and usability.
I have progressed in my research regarding the technique and I am applying it with design managers. Hopefully, I will publish something about it in 2017 (HCII).
- 7Do you know any record about tsunamis in South Atlantic?
I would like information about tsunamis in South Atlantic.
You may like to have a look at this link for Tsunami affecting South Atlantic:
- 1Good papers that compare growth factor signaling responses over multiple cell lines.Often growth factor signaling is studied and ultimately modeled in individual cell lines. I am looking for studies were a number of cell lines were treated with on or more ligands and the responses were evaluated for all lines. In addition, I am looking for recent papers where growth factor signaling was modeled in multiple cell lines and general rules and regularities about signaling responses were extracted.
The literature of ErbB signaling alone is vast and I worry that I am missing interesting papers on PubMed or Google Scholar. Thanks for your help.
I am not sure that the attached article can be of help.
It is an old article (> 20 years!!) and indirectly relating to "growth factor signaling".
- 1Explain about Epoxidized Soybean oil Acrylate Polymer?
Polymer Properties (Physical & Chemical)
How it is different from other polymers? fibres ?
Thanks In advanceFollowing