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Why does spider angioma appear only on a skin of the upper part of a trunk in cirrhosis?
Have you seen other location of this sign?
Spider angiomas on skin correspond to gastropathy, enteropathy, colopathy that occur internally in the GI mucosa in cirrhosis and portal hypertension and the pathogenesis are the same i.e.increased amount of large number of vasodilators in the portal circulation that are not metabolised by the cirrhosed liver. Most probable cause of location in the superior vena cava drainage area in that maximum blood in the portal circulation that cannot go through the liver due to fibrosis reach the systemic circulation through the SVC as has been documented in the pathogenesis of esophageal varices in addition to the vasodilation.Following
What does the negative sign mean in Langmuir's isotherm?
This is langmuir' equation
Qe = QmbCe / (1+bCe)
where as Qe= heavy metal adsorbed to adsorbent (mg/g)
Qm = maximum adsorption capacity (mg/g)
b= langmuir 's constant
Ce =equilibrium concentration of heavy metal solution (mg/)
when i set it as LINEAR
1/Qe = 1/Qm + (1/bQm)(1/Ce)
when i plot 1/Qe againt with 1/Ce
i got y = 81.6X -6.8
and i am wondering
1.what does it mean with this negative sign (-6.8)
when calculate the intercept Y = 1/Qm
2. i need to calculated
intercept Y = 1/Qm = 1/-6.8 so Qm = -0.14?? or only 1/6.8
Thank you for you help :))Following
Is there any pre-layout method to determine the bitlines/wordlines capacitances of a SRAM cell/Array for a given technology node ?
Since sometimes we don't have layout drawing tool for the given technology node (say 22 nm or 16 nm) .
And also it is very difficult to draw layout to determine these capacitance especially when we only concentrate on spice simulation of the circuit. Is there any analytical method
Please refer to the book in Title: CMOS VLSI Design: A Circuits and Systems perspective
By: Neil E. Weste and David M. Harris
Chapter 2 and 4Following
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.
There is clearly a misunderstanding between us.
I didn't ask you for references supporting your specific hypothesis that thalamus is a 'center of consciousness' or even "the central receiver for sensory input , the central hub that directs etc".
I asked you for references supporting the hypothesis that there could be a 'center of consciousness'.
But, now, you say you no more support it (!).
So, the discussion is over now.Following
How to run a quantile regression with instrumental variable but the endogeneous variable is not a dummy in STATA?
When using the quantile regression to estimate the effect of the number of bidders on final price in online auctions, the number of bidder is an endogeneous variable. I decide to use the duration of auction and peak time dummy as the instrument variables. How to run such quantile regression in STATA when the endogeneous variable does not take the value of 1 or 0?
there are two methods first you solve the IV problem in OLS frame work then use QR other method is direct in QR using stataFollowing
How can I extract a biosurfactant produced by bacteria in a suspension? How do I test the activity of this biosurfactant?
this bacterial suspension is grown on MSM liquid added to the crude oil (1%)
Hi, I agree with Mr. Haytham M. M. Ibrahim, but i want to add some point. :
First we have to remove the bacterial cells by centrifugation (10,000 rpm 4oC, 20 min ) then add 6N HCl to reduced the pH of supernatant to approximately 2.0 this will precipitate the biosurfactant. Keep the the acidified suspension in the refrigerator 4oC overnight. then centrifuge again and keep the mass ( partially purified biosurfactant) remained at the bottom of tube. now you can dissolve it in ethyl acetate and start thin layer chromatography with different solvent systems including hexane/ ethyl acetate or chloroform/ methanol/distilled water.Following
What is the interpretation of humps (broad peaks) in a XRD pattern which repeat themselves in a exact range?
We are using RF magnetron sputtering for coating VANADIUM (30-50nm) on various types of substrate. After obtaining the XRD results, there are two humps with wide range. Despite their different intensity in different samples, they have quite exact points for rising and falling in every cases. So I don't think that they are due to amorphous property of sample. These humps also are independent of grain size of coated vanadium since the AFM images shows different grain sizes for different samples, while there is no change in the hump ranges.
Attached, there is a XDR pattern of one of the samples to show these humps.
Later attached: XRD patterns for naked Si, SiO2/Si substrates and XRD system configuration details.
Maykel, we are not using the GIXRD analysis. Our system works with conventional θ/2θ scanning method.Following
What is your experience about devices for dissection of liver parenchyma ?
What about Harmonic scalpel, Ligasure, Radiofrequency, Cavitron ? Which do you prefer ? Why ? and When ?Following
Can anyone suggest the bibliography for relation between national spatial planning and urban expansion?
I am interested by the postcommunism evolution.
Thank you, but for the moment I am engaged in sveral project with topics not related to topical issue.
All the best.
How do countries promote their heritage tourism through GIS applications?
The discussion is about GIS applications used by different countries for promoting their heritage tourism. Everybody is welcome to share opinions and expertise.Following
Controlling any non-zero active or reactive power during short circuit conditions?
when we used the droop control method for power sources, controlling any non-zero active or reactive power during short circuit (grid voltage equals zero) results in infinitely high currents, which is avoided when controlling the active and reactive current directly.
dose any one explain difference between the active and reactive power control in contrast to active and reactive current control?Following
Can anyone help me with the construction of Lyapunov function for non-linear systems of differential equations?
I am currently working on my masters thesis "Mathematical modelling of Leptospirosis". I have this serious problem with the construction of lyapunov function to investigate the stability of the system, as it is known that there is no exact method for the construction of lyapunov for non-linear systems. Thanks
Could you give more details please!Following
How can I normalize an ELISA?
I used positive and and negative serum for optimizing an ELISA, but there is a difference between each sample. The total antibody content is different from person to person.
So, it is not convenient to compare direct absorbance values obtained for serum samples. The values should be normalized for analysis. How can I normalize the OD values obtained for different serum samples?
Actually I want to know , What is your aim? In an ELISA you are taking Positive and Negative serum Sample. Titre of both and many other will differ. If you want to normalize the 'titre'" you have to take a control pool serum (that should from all category) in all plate and convert OD in to ELISA unit. If you want to declare positive or negative from the OD value you have select a cut off value negative. That can be done by pooling 10-12 mean OD + 2SD of negative samples. Further if you want to quantify the antibody, you have to take a known (quantitatively identified) serum. Then you convert then to quantity as ng/ml or pg/ml.Following
Are there any calcineurin pathway studies in prion infected laboratory animals?
Can anyone suggest some Antibiotics that alters calcineurin levels in brain?or any drug that can change levels of pCREB and pBAD levels in brain?
PLoS Pathog. 2010 Oct; 6(10): e1001138.
Published online 2010 Oct 7. doi: 10.1371/journal.ppat.1001138
Calcineurin Inhibition at the Clinical Phase of Prion Disease Reduces Neurodegeneration, Improves Behavioral Alterations and Increases Animal Survival
Abhisek Mukherjee et al
Prion diseases are a group of infectious neurodegenerative disorders producing a rapid and devastating clinical deterioration. The disease is 100% fatal and affected patients usually die within one year from the appearance of the first clinical alterations. Currently there is no treatment available for these diseases. The main goal of this study was to show that inhibition of the brain phophatase calcineurin is a therapeutic target for prion diseases. We show that calcineurin is hyperactivated as a consequence of endoplasmic reticulum stress produced by accumulation of misfolded prion protein. Treatment of animals showing the symptoms of prion disease with the calcineurin inhibitor FK506 resulted in a substantial decrease in the severity of clinical signs, an increase in animal survival and a reduction in brain degeneration. These findings indicate that calcineurin might play an important role in prion-induced neurodegeneration and inhibition of this phosphatase might represent a promising novel approach for prion disease therapy.Following
Is there any information on linear ordered topological structures?
Could linear ordered topological structures, I am looking forwards to expertise this fileld which became actual since falling past XX, be related to your subject I believe, differential geometry? Just can find Differential Manifolds, Brickell F. and Clark, R. S. in my library say, times where I was a student ... Thank you.
Thank you, dear Yuriy, I believe I possibly can obtain the paper. I found an application of Schauder basis, linear funct. analysis, to a difficult problem in general topology. Wickstead, Vector and Banach Lattices I could obtain the pdf. through the googleFollowing
Is there a solid counter-argument against Dingle's old objection to Relativity Theory?
Herbert Dingle's argument is as follows (1950):
According to the theory, if you have two exactly similar clocks, A and B, and one is moving with respect to the other, they must work at different rates,i.e. one works more slowly than the other. But the theory also requires that you cannot distinguish which clock is the 'moving' one; it is equally true to say that A rests while B moves and that B rests while A moves. The question therefore arises: how does one determine, 3 consistently with the theory, which clock works the more slowly? Unless the question is answerable, the theory unavoidably requires that A works more slowly than B and B more slowly than A - which it requires no super- intelligence to see is impossible. Now, clearly, a theory that requires an impossibility cannot be true, and scientific integrity requires, therefore, either that the question just posed shall be answered, or else that the theory shall be acknowledged to be false.
Yes there is not carrier at all in the QE.Following
Can anyone suggest me a good Ab to stain CYP11A1 (cytochrome P45011a1) on tissue?
I have a problem. I'm trying to stain CYP11A1 on Mouse tissues embedded in parrafin or frozen but I can't find a good Ab.
I tryed 3 different Ab on mouse testis and adrenal gland (positive control) embedded in paraffin or frozen in OCT . I changed many protocols (antigen retrival, blocking, Ab concentration, washing buffers, timing, etc etc) I wrote to all techical support and to authors of papers who used the same Ab but I never was able to obtain a good and specific staining (low signal and high background).
These are the Ab I used:
- Abcam cyp11a1 ab 75497
- Santa cruz cyp11a1 (D-16) sc18040
- Proteintech 133663-1-AP
Can you suggest a different Ab to use?
Maybe the link below is helpful for you to find an appropriate antibody:
Regarding the ab´s you tested:
- The abcam-ab is reactive in human tissue only. Maybe that´s the reason why you can´t establish it on mouse tissue. Usually Abcam antibodies are good and their technical support is also helpful.
- Personally, I don´t like santa cruz abs. They tend to be unspecific. So I wouldn´t spend more time in establishing this one...
- The Proteintech ab, has not been tested in IHC as stated on their website. It could be difficult to get this one to work.
Could anyone help me with Huntington's disease dataset or at best ,where can i get dataset.?
I completed my academic master's project.......I designed a small tool for Huntington disease prediction. I need Huntington dataset containing age and age of onset to proceed validation or modelling using fuzzy neurons.....could you help me with dataset or at best ,where can i get dataset.
Thanks and Regards,
Genotyping and clinical examination determined that 171 participants were presymptomatic gene carriers (PSGCs) and 414 participants were non-gene carriers (NGCs). The PSGCs performed significantly worse when compared with the NGCs on the digit symbol, picture arrangement, and arithmetic subscales of the WAIS-R (p<0.02) and for the physiological measures: button tapping, auditory reaction time, visual reaction time with decision, and movement time with and without decision (p<0.05). Although no PSGCs had sufficient neurological findings to warrant a diagnosis of Huntington's disease on clinical examination, the PSGCs had more frequent possible or definite abnormality for oculomotor function, chorea, muscle stretch reflexes, gait, and station stability, and rapid alternating movements (p⩽0.02)
J Neurol Neurosurg Psychiatry 2000;69:773-779 doi:10.1136/jnnp.69.6.773
Subtle changes among presymptomatic carriers of the Huntington's disease gene
S C Kirkwooda et al
There are studies that analyze the dynamics of fluids in the carotid arteries?
Even through computational analysis, comparing patients with or without carotid plaque? ThanksFollowing
How can we calculate malondialdehyde (MDA) contents ?
I have noted absorbance at 600, 532 and 450 nm for MDA, but, unable to calculate it. Would anyone please like to guide me based on information provided ?Following
Can anyone help me with DNA not dissolved in water when extracted from Ascochyta?
Whenever I do DNA extraction from Ascochyta, at a stage when I want to dissolve the DNA in water, the DNA is partially or do not dissolve at all. Anyone may help me?
@ michael, i will try ur suggestions might help.
@ Irfan, what you are saying is at the last step of DNA isolation, where TE buffer is used and stored as such. but my problems starts before that. after precipitating alcohol washing, and the dissolving with pure water. Here my DNA doesnt dissolve and face difficulty in subsequent RNAse treatment.Following
Concerning research in emotional responses to music, has someone done a study correlating musical devices and mental states in performance?
In my submission "A Brief History of Modulation in Musical Rhetoric and Brahms' Harmonic Ambiguity ", I identify the need for a study to correlate musical devices and mental states. The first step is to develop[ a catalog of such devices. These include among many effects, modulation (shifts in tonicity), silence, unison, changes in rhythmic texture etc.
By using the term "mental states", I choose a broader field than mere "emotion".
With an understanding of composition/improvisation (generative), there are a great many possibilities. Just within modulation, Max Reger has developed an extensive catalog of the devices, alas no mention is made of effect on an audience. Rameau in his treatise on Harmony discusses very briefly an emotional response to chromatic modulation (please see my article for the citation specifics; Reger is not cited in this paper yet. It remains in an unfinished form: more than a few citations TBD.
Gee, how do I put a citation here? - simple footnote:
Max Reger: Modulation (Dover Books on Music) Paperback 2007
Jean-Philippe Rameau: Treatise on Harmony Dover 1971
Study in the link seems to confirm the belief that music is a universal language.A language containing semantic structures that are comprehensible to a wide and diverse range of individuals.Musical devices are definitely an important unit of analysis in the analysis of a piece of music's semantic structure. Musical devices especially those related to the Baroque era may have a universal impact on the mental states with regards to "movement planning, memory and attention". Especially music's role in helping the brain to " foreshadow".Following
Any scientific research on self-determination theory (Deci & Ryan, 2000 ?
I'm working on an introduction program voor students at the age of 14/ 15 years old in Veldhoven Holland. I use the self-determination theory (Deci & Ryan, 2000) as my fundament in the program. Is there any scientific research that proves that their concept is working. It is evident based, but I can't find any proof.
Antoon van Wolferen
Thank you very much I will read them
have a nice weekend
Is 63.5% the optimal acid concentration for isolation of cellulose nanocrystals from MCC?
According to Bondeson, that used response surface methodology for optimization of the acid hydrolysis procedure for preparation of CNWs from MCC, the optimized treatment condition is as follows:
63.5% acid concentration (sulphuric acid)
temperature= 45 C
time= 130 min
however, some researchers believe that MCC will dissolve at this high acid concentration and as a result amorphous particles are formed and the yield is low. In an article, acid concentration 57-60 % and time 40-60 minute has been proposed as the optimal codition for the acid hydrolysis process.
Anyone familiar with diazonium coupling of silk?
I have done diaotization of light chain silk for modification of tyrosine present in it. I tried H1-NMR and ATR-FTIR on these modified silk. But no peak was observed, from dizonium salts in both of these characterization, Is there any technique to determine that silk material is diotized and %diaotization done after completion of experiment?
Diazonium salts with aliphatic substituent ( like in tyrosine) are unstable and rapidly lost nitrogen with building of alcohol (in water media). This is good method of R-NH2 -> R-OH transformation.
Dry diazotization (via Ar-NH2 -> Ar-N=S=O + NO+BF4- -> Ar-N≡N+ BF4- ) is known in aromatics but to be explored in aliphatics.Following
What is the relationship between hermeneutics, dialogue and multiculturalism in the context of modernity?
I need information on these issues and their conceptual relationship.
Hermeneutics, as the art of interpretation of the phenomenon helps us to appreciate the essence and explain the importance of dialogue and multiculturalism in the context of modernity.Following
How do coded apertures improve imaging resolution?
Why is it that we get a better resolution when using coded apertures as opposed to pixel-by-pixel imaging?
coded apertures are a Deconvolution technique, which uses a prior knowledge about the reconstructed signal.
see attached link for example.Following
Liver surgery: What is optimal simultaneous or staged liver resection?
Up to 15% of patients with colorectal cancer have synchronous liver metastases. Wich is optimal timing of hepatectomy ?
Thank you dear colleagues for your comments. The variety of your considerations underline the importance of experience as well as results reported in literatureFollowing