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- 7I want to wash my leucocytes cells with HBSS and adjust to 10 viable cells per mL.Could anyone explain to me how to practically do this?
I want to wash my leucocytes cells with HBSS and adjust to 10 viable cells per mL.Could anyone explain to me how to practically do this?
My above protocol assumes that we know enough about our cells of interest to be able to do single cell plating as was first done by Puck Marcus and Cechuria for Hela cells. If the cells need to condition the medium, then one can grow the cells at higher voncentrations, filter the medium to re move cells and plate at lower concentration in a mixture of fresh and conditioned medium. If one is not doing single cell plating, one cannot measure clonogenicity or reproductive integrity, except by much less precise indirect methods.
Thanks to Prof Gerwick and Dr. Prinholata da Silva for their kind comments.Following
- 1Is it possible to write custom User subroutines for ABAQUS based on UEXTERNALDB?
I would like to write a user subroutine that modifies the boundary conditions of a job at each increment, based on values it receives from a TCP/IP socket connection. The first problem/question is:
Can I write custom user subroutines for Abaqus other than the default ones or can I modify the UEXTERNALDB to call a "TCP/IP socket server module" to wait for data at a port, then use the data to modify the boundary conditions and then output the resulting displacement data as the response to the external client. The reason for this complexity is to allow me get this data as soon as it is ready instead of waiting for the files to be written to disk and accessing the obd.
You can use UEXTERNALDB to wait for external data (as long as you run on a single processor, otherwise, I'm not sure).
If you want to change things inside your model, you then have to communicate the input to other subroutines (like user-defined boundary condition), usually via a COMMON block.Following
- 12How can i reduce the stress on a ultrasonic device?
I am attempting to create a ultrasonic device which consist of a stepped horn connecting to a transducer and a blade using aluminium instead of the standard material (titanium). However, i am getting a stress of 790 Mpa and the tensile strength of aluminium 6061 is about 200-300 Mpa. Please let me know if anyone knows any ways of reducing stress in ultrasonic devices.
I don't see the surfaces in red. Can you describe where these are and post another image showing these more clearly?
For your initial FEA, you should analyze without any supports (i.e., completely free) to get the true frequencies and then harmonic analysis with stresses. After the horn has been optimized as you desire, you can then add the support and optimize it also. (I assume by "support" that you mean an external support structure rather than boundary conditions. In either case, the initial FEA model should be completely free.)
What is the purpose of the groove?Following
- 3The most reliable indicators of nutritional status in birds?
Based on your experience, what do you think are the most reliable indicators of nutritional status in birds?
I would like to measure them in both adults and nestlings of seabirds.
Many thanks and best regards
The power of birds can be when it have long song and many birds sounds... It's can be indicate the nutrition and energic status of birds.Following
- 4Anyone knows records of Heliothis subflexa on cultivated tobacco plants?
The larvae of Heliothis subflexa feed exclusively on fruits of Physalis species, the only known hostplant record in United States. I found larvae of H. subflexa feeding on Nicotiana tabacum (Solanaceae) in Colombia. This competes for food with Heliothis virescens, a related species.
Thank you very much for the excellent thesis work about Heliothis subflexa and the records on Nicandra in Perú. I found another record of H. subflexa on tobacco in Kentucky, United States
- 7How do I prepare Amberlite XAD-4 resin to use in separation?
I am trying to prepare Amberlite XAD-4 resin prior to using in a column. I cannot find the basic procedure for preparing the resin when it comes straight from Sigma before packing the column. Any suggestions? Thanks!!
Add the resin as a slurry in water. Fill the column to only 50 - 60%, to allow room for backwash. Drain water level to 2 - 5 cm above the top of the bed. Start by backwashing the resin, to remove air pockets and any fines. To do so, pump water from bottom to top at a rate sufficient to expand the bed.(see Figure 4 of the link Bruce sent). Allow the bed to expand to the top of the column, then stop water flow, allow the bed to resettle, then again drain until the level is 2 - 5 cm above the top of the bed. Next rinse with ethanol (or other suitable polar solvent) for 90 minutes at 2 - 2.5 bed volumes (BV) per hr (top to bottom). Displace the ethanol with water (30 minutes, 2 - 2.5 BV/hr), then rinse with water for one hour at 8 - 10 BV/hr. Repeat these steps twice (total of three), then do a final backwash. Now your column is free of preservatives, residual monomer, fines and air pockets, and it's ready to go.Following
- 8How to remove RNaprotect from lysited cells before RNA extraction?
my samples are disrupted cells in RNAprotect + PBS. I have tryed to perform RNA extraction using Trizol but i get litle RNA concentration and pourly clean. Any suggestions about removing the RNA protect? Thank you
sorry, i meant 100ng to the rt reactionFollowing
- 39Who is a sycophant? Is sycophancy an Art?
We see sycophants in all the fields - political, social, administrative ......
Do you think it is an art that is harmless or something that harms the organisational culture severely.
What kind of sycophants are prevalent in your part of the world.
Sycophancy is flattery and stooge. Only the one who do not want to work hard use the art—selling dignity for benefit.Following
- 99+Is Chalmers' so-called "hard problem" in consciousness real?
In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?
“Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."
Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".
Personally, I agree with Stanislas Dehaene's opinion.
Shown below is the distribution of the % of filter-cells with activation levels within 10% of the observed peak/winning response in a face recognition test of my cognitive model. This is taken from “Sparse Coding of Faces in a Neuronal Model: Interpreting Cell Population Response In Object recognition” on my RG page. It seems to conform to a typical Poisson distribution. Is this relevant to your math model of cognitive processes?Following
- 1Problem with solving zero size elements near the notch in mesh during analysis?????
I have modeled a piping component (half model) with a surface notch upto 4 mm whereas the total thickness is 14.69 mm in abaqus. My job is to find out the stress intensity factor and strain energy using CONTOUR INTEGRAL. Here I attach the error in pic. can u pls let me know how to solve it????
NOTE : I have Tetragonal mesh as only option for meshing in which some of the regions around the crack tip were found to have zero size elements
As the manual (analysis, section 11.4.2) states
"can be used only with two-dimensional quadrilateral elements or three-dimensional brick elements when used with the conventional finite element method;"
So you simply have to re-mesh your structure using quads/bricks in the region of your crack tip.
For better resolution of stress fields, it may be helpful to use a quarter-point mesh, see the subsection
Constructing a fracture mechanics mesh for small-strain analysis with the conventional finite element methodFollowing
- 4Is it correct practice to measure effect of BMI on pregnancy outcome?
Many researchers measure BMI during time of delivery. IS it correct practice? because if you want to see effect of BMI on pregnancy outcome then we have to use BMI of woman before attainment of pregnancy...need some experts advice regarding this...
Dear Dr. Patel,
Obesity is directly connected to bad obstetric outcomes.
A well known complication is shoulder dystocia, and diabetes, but there is research supporting that higher BMI- especially in obese range- may increase cerebral palsy in infants.Following
- NewWhy is using system-GMM so complicated and confusing?
I may incur the wrath of very senior colleagues on topics relating to using system-GMM, but I've come to my wits ends and to be honest, right now I am very, very confused.
I'm using Stata13 and I actually thought I am good with GMM (yes, with difference-GMM)...but applying sys-GMM to my model is going the wrong way.
Having read materials relating to GMM and particularly David Roodman's paper several times, I've tried to set up my model using the format stated in the paper, but my results are getting awry.
It's either the Hansen test statistic is hitting the 'implausible' 1.000 mark, while the Sargan seems reasonable (0.794) and we're told that the Hansen-J statistic is more robust...so attempt to correct the H-J, got me confused the more!
Please I need assistance...I have an unbalanced panel data set. T=45, N=1620, the variables are lnFDI (dep. var) while the explanatory variables are lngdp, lngdppc, credit, natural resources and trade openness.
Any ideas on how to arrange these in Stata using xtabond2?....I've already used pooled OLS and Fixed Effects estimators I only need the sys-GMM estimation to support my argument...and honestly, I think GMM is really complicated (my opinion, though).
- 21Can the concept of reflexivity be applied to migration at large rather than limiting its application to the lifestyle migration?
My Ph D supervisor who is a sociologist, is asking me to consider Giddens' concept of reflexivity in analysing migration phenomenon. I don't have a sociology back ground, but from the initial reading it seems to me that it does make sense to assume that migrants do make a "reflexive assessment" of the opportunities related to migration. However, I don't think that this is a process that should apply only to middle class skilled migrants who want to change their lifestyle. In ultime analysis all migrants being these unskilled or not, low or upper income, move because they make an assessment of their current situation and believe that they will be better off in another place
I apologise for multiple-posting - this is more technological glitch rather than a discursive attempt to monopolise a conversation, of which the original question asked has been lost. For that I apologise to Bruno.
Ricardo - I am not a leftist: yes, I am in support of multiculturalism but I also see its weaknesses as a concept (which hardline left-wingers would not see). My research looks at the threats of diversify in rural Britain so as to help promote greater, and better integration rather than live in an in-flux, protean world of fear and risk. By no means is in support of any agenda!
Furthermore, what is this nonsensical talk of a Western cover-up to excuse the actions of specific groups? Ricardo, I hate to tell you but there is no such thing. People's recursive actions (both discursively or tacitly) have consequences and/or global implications. The migration of specific people to certains parts of the world and the actions they do is just one of them. I do not condone the raping of anyone by anybody - just be careful not to villify specific groups of people because the world does not need to become any more uglier than it already is.Following
- 8Does anyone know of reports indicating that the cattle tick (Rhipicephalus microplus) affects dogs?
Or maybe you have experience about these ticks developing in dogs?
Thanks a lot!!
Es gibt Arbeient auf die der Index-catalogue of Medical and Veterinary Zoology von 1974 verweist.
Díaz-Ungría, C. (1957A): 457-46 (Bos taurus, Equus caballus, Connochaetea gnu, Canis familiaris, hombre; Venezuela)
Ressang, A.A. ; Fischer, H. & Muchlis, A. (1959a) 55-99. Equus caballus, cattle, Bubalus bubalis, Sus ssp., Canis familiaris; Indonesia
Seddon, H.R. (1947A) 1-41, horse, ox, sheep, dog, pig, rabbit, kangoroo, wallaby (Australia)
Maa, T.C. & Kuo, J.S. (1966A), 373-413 Bos taurus, Bubalus bubalus, Canis familiaris, Macaca cyclopis, Sus scrofa taivanus; Taiwan
Cassamagnaghi, A. et al (1951A) - Bos taurus, Equus caballus, Canis familiaris, Cervus campestris, Uruguay
Boero,m J.J. (1955A): Homo sapiens, Bos taurus, Bos indicusw, Equus caballus, Ovis aries, Capra hircus, Canis familiaris u.a.; ArgentinienFollowing
- 4Why do I get difference in Copy Number estimation (software via Excel)?
I would like to understand calculations made by qPCR software. I create a standard curve in Excel with same parameters as in software with equation for my target: y=-1.571ln(x)+39.433 and calculate CN from exactly same Ct (same decimal places).
x (CN)=((y(Ct)-39,433)/1.571)^e; where (e=2.71828183), and after normalization against used amount (ng) and genome size, I get average CN=8.69, but software result is 8.71.
Then I try equation used in the software : Ct=m[log(Qty)]+b, from that x=10^((Ct-b)/m), where b is y-intercept (= 39.433 in this case); m=slope. I get similar results, but not exactly the same average: CN=8.72.
where I'm wrong? are there additional corrections or coefficients usually used in the qPCR calculations by software for absolute quantification?
Hi again Angelika,
variation of 100 copies out of a total of 4000 (or more) represents 2.5% (or less)... Is this not acceptable? Don't forget quantification is made from experimental Ct data input on a linear y-scale transferred onto a logarithmic x-axis (so any experimental error on Ct becomes exponential on CN: this is the 2.5% variability on your CN). To illustrate, let's say you calculated once CN=4000 copies, it means you actually measured Ct= -1.571*(ln4000)+39.433=26.403. If CN was 4100, it means Ct was 26.364... How different are 26.403 and 26.364? It's around 0.1%...
Finally, If your data comes from different plates, first you have to normalize the results from each plate (towards internal standard) before any further calculation.Following
- NewWhat is the upper limit of temperature and density in a supernova explosion
For heavy and superheavy element synthesis in supernova, the r-process nucleosynthesis is studiedFollowing
- NewWhich steps should be followed to integrate two different software process models to each other?
Recently, I am working on my course project, the topic is the creation of a new hybrid software process model by integrating Scrum and Team Software Process (TSP). Integration of these two models will be based on the SEMAT Essence Kernel Framework.
I am wondering:
- Which steps should be followed for this integration (like determination of the roles and artifacts in these two models)?
- What should be the criteria to decide on good sides?
Thanks in advance!Following
- 2Though both are required, among IL-6 or TGF beta which is important for Th17 pathway intiation?
Though both are required, among IL-6 or TGF beta which is important for Th17 pathway intiation?
Thank you sir.Following
- 1Which Blocking Buffer should be used for Mesenchymal stem cell (MSC) flow cytometry?
We want to do flow on MSC isolated form Umbilical Cord Blood for surface markers. for reducing background staining I think we must use blocking buffer. What is the ptotocol and components of blocking buffer for MSC flow?
MSCs don't have FcRs so you should be fine with any protein that blocks aspecific protein adsorption site. In practice I would do 0.1 - 0.5% BSA or 2 % FCS (but you could also use casein, it really doesn't matter). For primary, early passage MSC cultures you may have to deal with residual macrophage contamination they are also plastic adherent, but won't proliferate, so you 'lose' them by competition). In that case you might consider using some FcR blocking reagent.
For flow background staining isn't a huge problem usually, so you'll be fine if you remember to use a proper isotype.Following
- 1Can anyone help me with interpretation of Moran's I correlogram for a model residuals?
I am trying to test my preliminary MaxEnt model residuals for spatial autocorrelation in order to decide whether I need to rarefy my presence points. Since the data came from multiple sources (mostly literature and museum records), it is obvious that these records were gathered through different sampling effort and somewhat clustered in space. From the other hand, the species is rarely collected throughout its range (I have only about 300 points) and I would like to retain for modeling purpose as many records as I can. The method I use follows Nunez & Medley, 2011, who propose calculating Moran's I at multiple distance classes with SAM software. However, I am having troubles with interpretation of the results. Attached you can find the correlogram I am getting in SAM. From what I can see in the results, the first and the highest Moran's I value = 0.475 (p=0.005) is at distance of 64.007 and the rest has much lower values, with most of them being negative. Does that mean that my presence points can be filtered at minimum distance of 65 km or they are OK and show only weak SAC? I read somewhere that only significant values greater than +-0.5 or +-0.7 can indicate serious spatial pattern. Am I getting it right?
Another related question is: why the correlogram shows Distance units instead of km? I am choosing the Geodesic coordinate system when loading my data but the program keeps showing the distance in units...
I am absolutely newbie to SDM and spatial statistics, so any help/tips will be greatly appreciated!
In general, Moran's I can also be interpreted as slope of a linear regression line with the dependent variable y and the independent variable (regressor) W*y, where y is the vector of observations and W is a row-standardized spatial weighting matrix. For instance, one could choose W as row-standardized matrix of W_tilde, where w_tilde_ij = 1 if the distance between region i and region j is between 0 and 1km. In that case, the first entry of the matrix product W*y would coincide with the average of all observations, for which the distance from the first region is smaller than 1km. The second entry would be the average of all observations closer than 1km from the second location/region, and so forth. To summarize, W*y are the average observations within a distance in the interval (0km, 1km]. Of course, one could also choose any other interval.
The idea of the plot, which you have attached, is to assume that the weighting matrix W depends on the distance interval, i.e., Moran's I is calculated for several "distance classes" (e.g., (0km,1km], (1km,2km], (2km,3km], ...). I am not familiar with the SAM software, so you should check, which distance intervals are assumed to calculate the Moran's I (red dots). The intervals could also be (0,1km], (0,2km], (0,3km], and so on. For instance, If the first interval is (60km, 65km], Moran's I indicates that the spatial correlation is 0.475 between all locations, which have a distance between 60km and 65km.
If the distance between all your locations can take only a discrete number of values (e.g., 60km, 170km, 300km, ...), it is not necessary to consider the "distance classes". In that case, Moran's I can be calculated for each of the possible distances (and I suppose, it is represented as red dot in the shown figure).
In order to check whether this spatial autocorrelation is significant, you should calculate confidence intervals. The mean and the variance of the Moran's I statistic can easily be calculated (cf. also: "On the Asymptotic Distribution of the Moran I Test Statistic with Applications", Kelejian and Prucha (2000)). Regarding your plot, I suppose that Moran's I differs significantly from zero, if the red dot is outside the red 95%-confidence band around zero.Following
- 4How can I find the koyna-1967 earthquake time history for the station near the koyna dam in India?
I have trying to find out time history data for Koyna Earthquake. Can someone help me? I searched in " http://ngawest2.berkeley.edu " and " strongmotioncenter.org/vdc " and I found nothing. I need the the station data near the dam
The digitized data (manual) was published in BSSA in 1967. I remember this was at unequal intervals. Later I think it was interpolated to equal time steps. I will search my collection for a copy if available.Following
- 16Who knows the properties and the working principle of this circuit?
Recently I came across with the shown circuit.
It has some interesting properties. Is there anybody who has used such a circuit already? Both opamps are assumed to be ideal.
Pros and cons?Following
- NewHow can spin glass and spin ice can be experimentally distinguished?
How can spin glass and spin ice can be experimentally distinguished?Following
- NewCould we estimate the total calculation time for VASP?
I want to know when my job for VASP will finish.
I know how long time it spent from OUTCAR but I want to estimate the CPU time (or real time) it needs for a job when it is executing before the finish.
I can't find the solution from googling...Could I know it?
- 4Does anyone know academic papers on learning about oneself?
Does anyone know articles / academic papers on learning about oneself?
Academic learning is analyzed frequently focused on knowledge about the external world. Simultaneously, it practiced personal development. Also, psychological therapy facilitates learning about their own values, behaviors, attitudes and their changing. Does anyone know academic papers showing this process from the perspective of factors, conditions or mechanisms of this type of learning (learning about oneself)?
Thank for your help!
In relation to learning about oneself, there are two tools a colleague and I suggest people to use. The first is the Critical Incident technique as proposed by Broomfield and the other one is the Cooperative Development Theory designed by Edge. Both are really useful and simple to administer. The benefits go beyond the profesional scenario and the sense of improvement is felt almost immediately. For the implementation of the technique, you need to count on your students, whereas for the implementation of the theory, it is good to have at least one teacher (though a group of teachers work better) who are motivated to listen to you without judging your views.Following
- 2What is the feasibility of implementing simulation research studies among novice nursing students?
What is the feasibility of implementing simulation research studies among novice nursing students?
Yes, I agree with Paul that simulations would be very feasible with your nursing students. Just remember that you may need to incorporate the use of technology in your simulations, so be aware of the cultural relevant of your choice of videos, graphics, and other media used. I have attached a short article that I hope would be of some use in planning to use technology in your simulations.
- 11Does anyone know a measurement method to measure a surface shape?
Does anyone know a measurement method to measure a surface shape with 65m diameter from 50m away? The operation temperature is about -40-60 c，the accuracy is about 0.1mm RMS?
You could take one or more UWB (Ultra-Wide Band) senors. By them you can measure the diameter and the deepness - thus in 3D - from an arbitrary position of your object, up to apprx. 100m.Following
- 99+Is it time we shift emphasis from technological solutions to climate change & focus on the 'Human Dimension'?
Isn't the obvious solution and the elephant-in-the-room 'BETTER HUMAN BEINGS'? Shouldn't the focus be on better human beings rather than better technology? Why is it that everyone wants to develop better technology rather than focus on better humanity? Because no one has the answers and no one wants to change themselves? In environmental degradation, is it not obvious that nature can heal itself, if only left alone, and it is we humans who need regulation? Many natural parks managers do just that; seal off the area from human interference to let nature heal and recover. It is classified as 'Strict Nature Reserve"by IUCN. Complacency and inaction are not advocated here, as many have misunderstood, but the shifting of focus from technology to the human being. As technology is no match for human greed, isn't introspection & restraining ourselves more relevant than developing more technology, which caused the mess in the first place, by making it easy for a few to consume more? Since technology is only a short term quick fix which fails after a short time, isn't the real problem our addiction to material consumption & our lack of understanding about human nature? Isn't developing more technology sustaining the addiction instead of correcting it, leading to more complex problems later on, needing more complex technological quick fixes like higher drug dosages, more ground troops & equipment, (along with their debilitating side effects) in the future? Isn't this the vicious addiction circle we are trapped in? As researchers, do we merely buy more time with technology OR go to the very root of the problem, the human being?
A lot of hue and cry is made about climate change and the environment in general. Public and private money is poured into research to study its effects on the environment, sustainability etc. Should we study nature or ourselves?
" Our studies must begin with our selves and not with the heavens. "-Ouspensky
Human activities have been found to have a direct correlation to climate change and its impact on the environment(I=P x A x T, the Ehrlich and Holdren equation), in spite of what some complacent sections say to protect their own self interests.
We hardly know about Human nature. We can scarcely predict human behavior. We need to find out why we think like we do and why we do what we do and why, in spite of all knowledge and wisdom, consume more than what we need, in the form of addictions to consumption and imbalance not only ourselves but also the family, society and environment around us..
Humanity is directly responsible for all the unnatural imbalances occurring on the planet. Yet we refuse to take responsibility and instead focus on climate change, or fool the public exchequer with a 'breakthrough in renewable energy just around the corner'. We scarcely know what drives human beings. If we had known, all the imbalances around us would have had solutions by now, given the amount of money plowed into finding such solutions. Are we blindly groping in the dark of climate change because we don't know the answers to our own nature?
Is it not high time we focus on what makes us human, correct our consumptive behavior and leave nature to take care of climate change? Why focus effort on 'externals' when the problem is 'internal'- 'me'?
Aren't we addicts denying our addiction and blaming everything else but ourselves?
" We are what we Think.
All that we are arises with our thoughts.
With our thoughts, we make the world." - Buddha
IMHO, We don't need to save the World. It is enough if we save ourselves from ourselves. The need of the hour is not vain glorious interventions, but self-restraint and self-correction!
The Mind is the Final frontier.
"Why focus effort on 'externals' when the problem is 'internal'- 'me'?"
"Me" is only "me", not the humanity in general. Humanity is external in relation to me. For "me" controlling other humans is as hard as controlling environment. Buddhist approach is about everyone being responsible for his own spiritual evolution. If you really try to create a theory how to control mass (not your individual) behavior in order to make them be ecologically aware, you will see that it might be impossible on large scale (although it works in small groups).Following
- 4Do you have an overall ranking for departments and a comparison mechanism?
Our department, Family Medicine at the College of Human Medicine, at Michigan State University is wondering if you provide any kind of a global ranking information and if there's a way for us to collect that data and be able to compare across other departments of Family Medicine?
Thank you so much for taking the time to share this. I have shared it with the powers to be at my institution to see if they would be interested in pursuing this process. I really appreciate you input!.
- NewI am looking for a PhD position relevant to Supply Chain, Logistics Management or Operations Management. If you know of any please inform me?
I am looking for a PhD position relevant to Supply Chain, Logistics Management or Operations Management. If you know of any please inform me?Following