998 resultados para INTERNAL GRAVITY-WAVE
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We develop several results on hitting probabilities of random fields which highlight the role of the dimension of the parameter space. This yields upper and lower bounds in terms of Hausdorff measure and Bessel-Riesz capacity, respectively. We apply these results to a system of stochastic wave equations in spatial dimension k >- 1 driven by a d-dimensional spatially homogeneous additive Gaussian noise that is white in time and colored in space.
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We prove a characterization of the support of the law of the solution for a stochastic wave equation with two-dimensional space variable, driven by a noise white in time and correlated in space. The result is a consequence of an approximation theorem, in the convergence of probability, for equations obtained by smoothing the random noise. For some particular classes of coefficients, approximation in the Lp-norm for p¿1 is also proved.
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Optical imaging techniques are well suited for following the dynamics of physiological processes in living cells. Total internal reflection fluorescence (TIRF) microscopy based on evanescent wave illumination (EWi) allows spectacular, real-time visualization of individual vesicle movements, fusions, and retrievals at the cell surface (i.e., within 100 nm of the plasma membrane). TIRF microscopy is an ideal approach for studying the properties of exocytosis and recycling in cultured astrocytes, particularly because these cells have a rather flat surface and contain secretory vesicles with sparse distribution. Among all populations of secretory vesicles, we focus here on synaptic-like microvesicles (SLMVs). We illustrate how TIRF microscopy using EWi is useful to study exocytosis and recycling of SLMVs at the single-vesicle level and, when combined with epifluorescence illumination (EPIi), can provide detailed information on the kinetics of exocytosis, endocytosis, and re-acidification at the whole-cell level.
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J Clin Hypertens (Greenwich). 2012;14:773-778. ©2012 Wiley Periodicals, Inc. Postmenopausal women are at greater risk for hypertension-related cardiovascular disease. Antihypertensive therapy may help alleviate arterial stiffness that represents a potential modifiable risk factor of hypertension. This randomized controlled study investigated the difference between an angiotensin receptor blocker and a calcium channel blocker in reducing arterial stiffness. Overall, 125 postmenopausal hypertensive women (age, 61.4±6 years; systolic blood pressure/diastolic blood pressure [SBP/DBP], 158±11/92±9 mm Hg) were randomized to valsartan 320 mg±hydrochlorothiazide (HCTZ) (n=63) or amlodipine 10 mg±HCTZ (n=62). The primary outcome was carotid-to-femoral pulse wave velocity (PWV) changes after 38 weeks of treatment. Both treatments lowered peripheral blood pressure (BP) (-22.9/-10.9 mm Hg for valsartan and -25.2/-11.7 mm Hg for amlodipine, P=not significant) and central BP (-15.7/-7.6 mm Hg for valsartan and -19.2/-10.3 mm Hg for amlodipine, P<.05 for central DBP). Both treatments similarly reduced the carotid-femoral PWV (-1.9 vs -1.7 m/s; P=not significant). Amlodipine was associated with a higher incidence of peripheral edema compared with the valsartan group (77% vs 14%, P<.001). BP lowering in postmenopausal women led to a reduction in arterial stiffness as assessed by PWV measurement. Both regimens reduced PWV to a similar degree after 38 weeks of treatment despite differences in central BP lowering, suggesting that the effect of valsartan on PWV is mediated through nonhemodynamic effects.
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A common training plan in general internal medicine was a brave enterprise started in 2011 in accordance with the common objectives of the Swiss Society of General Medicine and the Swiss Society of Internal Medicine. The next challenge will be the dissolution of the two Societies and therefore the creation of an unique new association in 2015. This is an extraordinary opportunity to bring together the specific qualities of each association and to create a new society. Issues, objectives and secondary benefits expected from the creation of the largest national society of a medical discipline are explored as a joint discussion in this article.
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Proponents of microalgae biofuel technologies often claim that the world demand of liquid fuels, about 5 trillion liters per year, could be supplied by microalgae cultivated on only a few tens of millions of hectares. This perspective reviews this subject and points out that such projections are greatly exaggerated, because (1) the pro- ductivities achieved in large-scale commercial microalgae production systems, operated year-round, do not surpass those of irrigated tropical crops; (2) cultivating, harvesting and processing microalgae solely for the production of biofuels is simply too expensive using current or prospective technology; and (3) currently available (limited) data suggest that the energy balance of algal biofuels is very poor. Thus, microalgal biofuels are no panacea for depleting oil or global warming, and are unlikely to save the internal combustion machine.
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General internal medicine (GIM) has flourished in the United States (U.S.). Unlike other subspecialties of internal medicine, however, GIM's evolution has not been global in scope, but rather appears to have occurred in isolation within countries. Here, we describe international models of GIM from Canada, Switzerland, Australia/New Zealand, Argentina, and Japan, and compare these with the U.S. model. There are notable differences in the typical clinical roles assumed by General Internists across these 7 countries, but also important overlap in clinical and academic domains. Despite this overlap, there has been a relative lack of contact among General Internists from these and other countries at a truly international GIM meeting; the time is now for increased international exchange and the "globalization" of GIM.
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Clinical practice in internal medicine has fundamentely changed over the last decade. Our knowledge has dramatically improved and we are facing new types of patients. Their number is increasing, they are older and suffer from increasingly complex medical conditions. The society has evolved as well therefore transforming our daily practice. This implies important modifications of our role and new challenges. We must also develop new aspects of our practice such as recognizing our errors, quality of care, quality of education, ethics, new strategies for taking care of the patient all this in parallel with continuous education. Our role as (general practitioner) is of utmost importance since it enables us to keep the "big pictures" in a more and more specialized environment.
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AASHTO has a standard test method for determining the specific gravity of aggregates. The people in the Aggregate Section of the Central Materials Laboratory perform the AASHTO T-85 test for AMRL inspections and reference samples. Iowa's test method 201B, for specific gravity determinations, requires more time and more care to perform than the AASHTO procedure. The major difference between the two procedures is that T-85 requires the sample to be weighed in water and 201B requires the 2 quart pycnometer jar. Efficiency in the Central Laboratory would be increased if the AASHTO procedure for coarse aggregate specific gravity determinations was adopted. The questions to be answered were: (1) Do the two procedures yield the same test results? (2) Do the two procedures yield the same precision? An experiment was conducted to study the different test methods. From the experimental results, specific gravity determinations by AASHTO T-85 method were found to correlate to those obtained by the Iowa 201B method with an R-squared value of 0.99. The absorption values correlated with an R-squared value of 0.98. The single operator precision was equivalent for the two methods. Hence, this procedure was recommended to be adopted in the Central Laboratory.
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INTRODUCTION: To compare the power spectral changes of the voluntary surface electromyogram (sEMG) and of the compound action potential (M wave) in the vastus medialis and vastus lateralis muscles during fatiguing contractions. METHODS: Interference sEMG and force were recorded during 48 intermittent 3-s isometric maximal voluntary contractions (MVC) from 13 young, healthy subjects. M waves and twitches were evoked using supramaximal femoral nerve stimulation between the successive MVCs. Mean frequency (F mean), and median frequency were calculated from the sEMG and M waves. Muscle fiber conduction velocity (MFCV) was computed by cross-correlation. RESULTS: The power spectral shift to lower frequencies was significantly greater for the voluntary sEMG than for the M waves (P < 0.05). Over the fatiguing protocol, the overall average decrease in MFCV (~25 %) was comparable to that of sEMG F mean (~22 %), but significantly greater than that of M-wave F mean (~9 %) (P < 0.001). The mean decline in MFCV was highly correlated with the mean decreases in both sEMG and M-wave F mean. CONCLUSIONS: The present findings indicated that, as fatigue progressed, central mechanisms could enhance the relative weight of the low-frequency components of the voluntary sEMG power spectrum, and/or the end-of-fiber (non-propagating) components could reduce the sensitivity of the M-wave spectrum to changes in conduction velocity.
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The Swiss postgraduate training program in general internal medicine is now designed as a competency-based curriculum. In other words, by the end of their training, the residents should demonstrate a set of predefined competences. Many of those competences have to be learnt in outpatient settings. Thus, the primary care physicians have more than ever an important role to play in educating tomorrows doctors. A competency-based model of training requires a regular assessment of the residents. The mini-CEX (mini-Clinical Evaluation eXercise) is the assessment tool proposed by the Swiss institute for postgraduate and continuing education. The mini-CEX is based on the direct observation of the trainees performing a specific task, as well as on the ensuing feedback. This article aims at introducing our colleagues in charge of residents to the mini-CEX, which is a useful tool promoting the culture of feedback in medical education.
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BACKGROUND: We have developed a nonviral gene therapy method based on the electrotransfer of plasmid in the ciliary muscle. These easily accessible smooth muscle cells could be turned into a biofactory for any therapeutic proteins to be secreted in a sustained manner in the ocular media. METHODS: Electrical conditions, design of electrodes, plasmid formulation, method and number of injections were optimized in vivo in the rat by localizing β-galactosidase expression and quantifying reporter (luciferase) and therapeutic (anti-tumor necrosis factor) proteins secretion in the ocular media. Anatomical measurements were performed via human magnetic resonance imaging to design a human eye-sized prototype that was tested in the rabbit. RESULTS: In the rat, transscleral injection of 30 µg of plasmid diluted in half saline (77 mM NaCl) followed by application of eight square-wave electrical pulses (15 V, 10 ms, 5.3 Hz) using two platinum/iridium electrodes, an internal wire and an external sheet, delivered plasmid efficiently to the ciliary muscle fibers. Gene transfer resulted in a long-lasting (at least 5 months) and plasmid dose-/injection number- dependent secretion of different molecular weight proteins mainly in the vitreous, without any systemic exposure. Because ciliary muscle anatomical measurements remained constant among ages in adult humans, an integrated device comprising needle-electrodes was designed and manufactured. Its usefulness was validated in the rabbit. CONCLUSIONS: Plasmid electrotransfer to the ciliary muscle with a suitable medical device represents a promising local and sustained protein delivery system for treating posterior segment diseases, avoiding repeated intraocular injections.
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This review is based on five articles published in 2006 and dealing with therapies in general internal medicine: in case of acute non complicated rhino-sinusitis, the use of topical corticoids in mono-therapy is indicated; cross-reactivity between penicillins and cephalosporins is less frequent than established so far. In our daily practice we should be more "pro-active" in prescribing probiotics which have proved their efficacy in the prevention of antibiotic-associated diarrhoeas; an antibiotic treatment of three days is recommended in case of non complicated cystitis in women less than 65 years of age. Finally, every patient treated with bisphosphonates must be regularly followed by a dentist.