177 research outputs found
The concurrent effect of one bout aerobic exercise and short-term garlic supplementation on the lipids profile in male non-athletes
زمینه و هدف: بیماری های قلبی- عروقی امروزه به عنوان یکی از عوامل تهدید کننده سلامتی انسان ها بخصوص در بیماران کم توان ذهنی محسوب می شوند. این مطالعه با هدف بررسی تأثیر دوازده هفته تمرین هوازی بر نیمرخ لیپیدهای سرمی و توان هوازی دختران کم توان ذهنی غیر ورزشکار طراحی و اجرا شد. روش بررسی: در این مطالعه کارآزمایی بالینی،22 دختر کم توان ذهنی با میانگین سنی 5/0±38/23 سال، قد 6/4±161 سانتیمتر، وزن 73/6±15/61 کیلوگرم، نمایه توده بدن 19/4±68/25 کیلوگرم بر مجذور قد و با بهره هوشی50 تا 75 به صورت نمونه گیری در دسترس انتخاب و به صورت تصادفی در دو گروه تجربی (10 نفر) و شاهد (12 نفر) تقسیم شدند. گروه تجربی در یک دوره تمرینات هوازی به مدت 12 هفته، با شدت 60 تا80 درصد ضربان قلب ذخیره شرکت نمودند؛ ولی گروه شاهد در هیچگونه تمرینی شرکت نکردند. متغیرها در دو گروه، در دو مرحله ی پیش و پس آزمون مورد مقایسه قرار گرفتند. یافته ها: قبل از آزمون بین دو گروه از نظر سن، قد، وزن و شاخص توده بدنی تفاوت معناداری وجود نداشت (05/0P). میانگین نسبت محیط کمر به باسن، درصد چربی بدن، لیپوپروتئین- کلسترول با چگالی بالا بین دو گروه تفاوت معنی دار ی نشان داد (05/0>P). نتیجه گیری: براساس نتایج این مطالعه فعالیت هوازی می تواند متابولیسم لیپوپروتئین ها را تغییر داده و سبب کاهش عوامل خطر ساز بیماری قلبی- عروقی در دختران کم توان ذهنی شود
Outcomes of Adult Patients with Small Body Size Supported with a Continuous-Flow Left Ventricular Assist Device
There is insufficient data on patients with small body size to determine if this should be considered a risk factor for continuous-flow left ventricular assist device (CF-LVAD) support. We sought to evaluate survival outcomes, adverse events, and functional status of CF-LVAD patients with body surface area (BSA) <1.5 m2 in a large national registry. Adults with BSA < 1.5 m2 (n = 128) implanted with a HeartMate II (HMII)-LVAD from the Interagency Registry for Mechanically Assisted Circulatory Support registry from April 2008 to December 2012 formed this cohort. Outcomes were compared with HMII bridge to transplant (BTT) and destination therapy (DT) post approval studies. The majority of patients were female (n = 106, 83%). A total of 64% (n = 82) were implanted for BTT and 36% (n = 46) for DT. The median BSA (range) was 1.44 (1.19–1.49) and 1.45 (1.25–1.49) m2 for BTT and DT, respectively. Overall survival 1 year post implant was 81% ± 5% for BTT and 84% ± 6% for DT. The most common adverse events for BTT and DT patients were bleeding (0.91, 0.88 events/patient year) and driveline infection (16%, 0.28 events/patient year). Six months post implantation, 87% of BTT and 77% of DT patients were New York Heart Association functional class I or II. Post implant survival, functional status improvement, and adverse event profile for adult BTT and DT HMII patients with BSA < 1.5 m2 are favorable and comparable with outcomes published in the overall patient population
Preliminary Mean-line Design and Optimization of a Radial Turbo-Expander for Waste Heat Recovery Using Organic Rankine Cycle
AbstractThis study presents an optimized modelling approach for ORC based on radial turbo-expander, where the constant expander efficiency is replaced by dynamic efficiency and is unique for each set of cycle operating conditions and working fluid properties. The model was used to identify the key variables that have significant effects on the turbine overall size. These parameters are then included in the optimization process using genetic algorithm to minimize the turbine overall size for six organic fluids. Results showed that, dynamic efficiency approach predicted considerable differences in the turbine efficiencies of various working fluids at different operating conditions with the maximum difference of 7.3% predicted between the turbine efficiencies of n-pentane and R245fa. Also, the optimization results predicted that minimum turbine overall size was achieved by R236fa with the value of 0.0576m. Such results highlight the potential of the optimized modeling technique to further improve the performance estimation of ORC and minimize the size
Characterization of Pharmaceutical Tablets by X-ray Tomography
Solid dosage forms such as tablets are extensively used in drug administration for their simplicity and large-scale manufacturing capabilities. High-resolution X-ray tomography is one of the most valuable non-destructive techniques to investigate the internal structure of the tablets for drug product development as well as for a cost effective production process. In this work, we review the recent developments in high-resolution X-ray microtomography and its application towards different tablet characterizations. The increased availability of powerful laboratory instrumentation, as well as the advent of high brilliance and coherent 3rd generation synchrotron light sources, combined with advanced data processing techniques, are driving the application of X-ray microtomography forward as an indispensable tool in the pharmaceutical industry
A Graph based architectural (re)configuration language
For several different reasons, such as changes in the business or technological environment, the configuration of a system may need to evolve during the execution. Support for such evolution can be conceived in terms of a language for specifying the dynamic reconfiguration of systems. In this paper, continuing our work on the development of a formal platform for architectural design, we present a high-level language to describe architectures and for operating changes over a configuration (i.e., an architecture instance), such as adding, removing or substituting components or interconnections. The language follows an imperative style and builds on a semantic domain established in previous work. Therein, we model architectures through categorical diagrams and dynamic reconfiguration through algebraic graph rewriting
Ventricular Assist Device implant (AB 5000) prototype cannula: In vitro assessment of MRI issues at 3-Tesla
Feasibility and efficacy of bypassing the right ventricle and pulmonary circulation to treat right ventricular failure: an experimental study
<p>Abstract</p> <p>Background</p> <p>Right ventricular failure (RVF) and -support is associated with poor results. We aimed for a new approach of right - sided assistance bypassing the right ventricle and pulmonary circulation in order to better decompress the right ventricle and optimize left ventricular filling.</p> <p>Methods</p> <p>From a microaxial pump (Abiomed), a low resistance oxygenator (Maquet and Novalung) and two cannulas (28 and 27 Fr) a system was set up and evaluated in an ovine model (n = 7). Connection with the heart was the right and left atrium. One hour the system was operated without RVF and turned of again. Then a RVF was induced and the course with the system running was evaluated. Complete hemodynamic monitoring was performed as well as echocardiography, flow measurement and blood gas analysis.</p> <p>Results</p> <p>The overall performance of the system was reliable. Without RVF no relevant changes of hemodynamics occurred; blood gases were supra normal. In RVF a cardiogenic shock developed (MAP 35 ± 13 mmHg, CO 1,1 ± 0,7 l/min). Immediately after starting the system the circulation normalized (significant increase of MAP to 85 ± 13 mmHg, of CO to 4,5 ± 1,9). Echocardiography also revealed right ventricular recovery. After stopping the system, RVF returned.</p> <p>Conclusions</p> <p>Bypassing the right ventricle and pulmonary circulation with an oxygenating assist device, which may offer the advantages of enhanced right ventricular decompression and augmented left atrial filling, is feasible and effective in the treatment of acute RVF. Long time experiments are needed.</p
4D microvelocimetry reveals multiphase flow field perturbations in porous media
Many environmental and industrial processes depend on how fluids displace each other in porous materials. However, the flow dynamics that govern this process are still poorly understood, hampered by the lack of methods to measure flows in optically opaque, microscopic geometries. We introduce a 4D microvelocimetry method based on high-resolution X-ray computed tomography with fast imaging rates (up to 4 Hz). We use this to measure flow fields during unsteady-state drainage, injecting a viscous fluid into rock and filter samples. This provides experimental insight into the nonequilibrium energy dynamics of this process. We show that fluid displacements convert surface energy into kinetic energy. The latter corresponds to velocity perturbations in the pore-scale flow field behind the invading fluid front, reaching local velocities more than 40 times faster than the constant pump rate. The characteristic length scale of these perturbations exceeds the characteristic pore size by more than an order of magnitude. These flow field observations suggest that nonlocal dynamic effects may be long-ranged even at low capillary numbers, impacting the local viscous-capillary force balance and the representative elementary volume. Furthermore, the velocity perturbations can enhance unsaturated dispersive mixing and colloid transport and yet, are not accounted for in current models. Overall, this work shows that 4D X-ray velocimetry opens the way to solve long-standing fundamental questions regarding flow and transport in porous materials, underlying models of, e.g., groundwater pollution remediation and subsurface storage of CO2 and hydrogen
- …