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Total artificial hearts (TAHs) are required for the treatment of cardiovascular diseases. In order to replace the native heart a TAH must provide a sufficient perfusion of the human body, prevent blood damage and meet the implantation constraints. Until today there is no TAH on the market which meets all constraints. So the purpose of this paper is to design a drive in such a way that the operated TAH meets all predefined constraints.

The drive is designed in terms of weight and electric losses. In setting up a cost function containing those constraints, the drive design can be included in a optimization process. When reaching the global minimum of the cost function the optimum drive design is found. In this paper the optimization methods manual parameter variation and differential evolution are applied.

At the end of the optimization process the drive's weight amounts to 460 g and its mean losses sum up to 10 W. This design meets all predefined constraints. Further it is proposed to start the optimization process with a parameter variation to reduce the amount of optimization parameters for the time consuming differential evolution algorithm.

This TAH has the potential to provide a therapy for all patients suffering from cardiovascular diseases as it is independent of donor organs.

The optimization-based design process yields an optimum drive for a TAH in terms of weight and electrical losses. In this way a TAH is developed which meets all implantation constraints and provides sufficient perfusion of the human body at the same time.

This study aims to pilot test a new multi-component worksite intervention for weight loss in a primary healthcare setting.

This randomized trial involved 88 participants (43, 45; intervention, control group). The intervention group enrolled in a 12-week lifestyle program that involved modification of dietary intake by community Registered Dietitian (RDs) and increasing high-intensity interval training (HITT) with motivational interviewing (MI) to support changes. The control group received traditional counselling and weekly aerobic exercise from Medical Officer and physiotherapist. The primary outcome measure was the changes in body weight. Secondary measures were changes in blood pressure, fasting blood glucose, fasting blood lipid and dietary changes. Assessments were repeated at a three-month interval.

There was a significant reduction in body weight and waist circumference within groups. Intervention group demonstrated a significant improvement in all cardiometabolic risk factors. This study showed that primary healthcare setting can be successful locations in promoting short-term health benefits. RDs were more successful and HITT appeared to be a favorable workout with MI in achieving drastic weight loss.

The short-term worksite intervention and not recording of body composition were the major drawbacks in this study.

The efficacy of multi-component worksite intervention (Diet–HITT–MI) in primary healthcare setting has not been clearly defined.

Gamification elements have been increasingly used in online weight-loss communities to help users lose weight. The purpose of this paper is to systemically examine whether and how social interactions influence users’ continued participation in the context of online weight-loss competitions (OWCs).

This study empirically investigated sustained involvement in OWCs using a Cox proportional hazards model. Additionally, the research utilized a text-mining technique to identify various types of social support and explored their roles in sustaining participation behavior in OWCs.

Community response both within and outside OWCs positively influence users’ continued participation in OWCs. Moreover, whereas emotional support and companionship received within OWCs have a greater impact on users’ continued participation than informational support received within OWCs, informational support received outside OWCs has a greater impact on users’ continued participation than emotional support and companionship received outside OWCs.

This paper highlights users’ social needs in OWC engagement and provides empirical evidence on how different types and sources of social support influence continued participation behavior in OWCs. The research additionally provides management implications for online health community service providers.

Ideally, there is no wear in hydrodynamic lubrication regime. A small amount of wear occurs during start and stop of the machines and the amount of wear is so small that it is difficult to measure with accuracy. Various wear measuring techniques have been used where out-of-roundness was found to be the most reliable method of measuring small wear quantities in journal bearings. This technique was further developed to achieve higher accuracy in measuring small wear quantities. The method proved to be reliable as well as inexpensive. The paper aims to discuss these issues.

In an experimental study, the effect of antiwear additives was studied on journal bearings lubricated with oil containing solid contaminants. The test duration was too long and the wear quantities achieved were too small. To minimise the test duration, short tests of about 90 min duration were conducted and wear was measured recording changes in variety of parameters related to weight, geometry and wear debris. The out-of-roundness was found to be the most effective method. This method was further refined by enlarging the out-of-roundness traces on a photocopier. The method was proved to be reliable and inexpensive.

Study revealed that the most commonly used wear measurement techniques such as weight loss, roughness changes and change in particle count were not adequate for measuring small wear quantities in journal bearings. Out-of-roundness method with some refinements was found to be one of the most reliable methods for measuring small wear quantities in journal bearings working in hydrodynamic lubrication regime. By enlarging the out-of-roundness traces and determining the worn area of the bearing cross-section, weight loss in bearings was calculated, which was repeatable and reliable.

This research is a basic in nature where a rudimentary solution has been developed for measuring small wear quantities in rotary devices such as journal bearings. The method requires enlarging traces on a photocopier and determining the shape of the worn area on an out-of-roundness trace on a transparency, which is a simple but a crude method. This may require an automated procedure to determine the weight loss from the out-of-roundness traces directly. This method can be very useful in reducing test duration and measuring wear quantities with higher precision in situations where wear quantities are very small.

This research provides a reliable method of measuring wear of circular geometry. The Talyrond equipment used for measuring the change in out-of-roundness due to wear of bearings indicates that this equipment has high potential to be used as a wear measuring device also. Measurement of weight loss from the traces is an enhanced capability of this equipment and this research may lead to the development of a modified version of Talyrond type of equipment for wear measurements in circular machine components.

Wear measurement in hydrodynamic bearings requires long duration tests to achieve adequate wear quantities. Out-of-roundness is one of the geometrical parameters that changes with progression of wear in a circular shape components. Thus, out-of-roundness is found to be an effective wear measuring parameter that relates to change in geometry. Method of increasing the sensitivity and enlargement of out-of-roundness traces is original work through which area of worn cross-section can be determined and weight loss can be derived for materials of known density with higher precision.

This paper aims to determine the best conventional degumming technique for use by rural farmers practicing Eri silk fiber production in Kenya.

Three conventional silk degumming methods (water, soap and alkali) were analyzed under the factors, namely, time, pressure and degumming media, following the multilevel factorial design of experiments. The effect of variables on degumming weight loss was determined. The effects of the conventional degumming methods that produced complete sericin removal on chemical structure, surface morphology, thermal properties, crystallinity and fiber strength on Eri silk fibers produced in Kenya were then determined. The optimal degumming condition was then evaluated.

Soap and water degumming led to incomplete sericin removal. Alkali degumming media had the most effect, especially when pressure cooked at 103 kPa. Increasing time during alkali degumming beyond 30 min did not to have any major difference on degumming loss (at p 0.05). There were no major changes in chemical and thermal properties after degumming. However, the tensile strength and elongation deteriorated especially on alkali medium. Decreasing degumming time in alkali medium from 120 min to 30 min reduced the strength loss from 45% to 33%. Optimal degumming was found to be in an alkali media at 103 kPa for 30 min.

There is very little information available on Eri silk fibers produced in Kenya. Results of this study provide an optimized conventional degumming procedure suitable for small scale farmers in rural areas practicing Eri silk fiber production.

We evaluate the hypothesis of temporal stability in risk preferences using two recent data sets from longitudinal lab experiments. Both experiments included a combination of decision tasks that allows one to identify a full set of structural parameters characterizing risk preferences under Cumulative Prospect Theory (CPT), including loss aversion. We consider temporal stability in those structural parameters at both population and individual levels. The population-level stability pertains to whether the distribution of risk preferences across individuals in the subject population remains stable over time. The individual-level stability pertains to within-individual correlation in risk preferences over time. We embed the CPT structure in a random coefficient model that allows us to evaluate temporal stability at both levels in a coherent manner, without having to switch between different sets of models to draw inferences at a specific level.

To provide an overview of recent research that collectively demonstrates the potential for peanuts as an aid to weight management.

Research on nuts and their effects on health has been plentiful in recent years. This short literature review focuses principally on that research relevant to peanuts.

Epidemiological and intervention studies have provided useful information on the beneficial effects of nuts, including peanuts in relation to weight management and obesity. This has served to overturn the perception that peanuts, due to their fat content, should not be included in weight loss diets. Furthermore, that, for effective weight management, a moderate fat diet, that includes peanuts, may be more effective for both cardiovascular health and weight management.

More definitive research to directly assess the effects of peanuts on energy balance and body weight is recommended to ascertain optimal quantities of peanuts that can be included in diets for both weight loss and weight maintenance. Plausible explanations for the absence of expected weight gain with regular nut consumption are reported and further research to explore these theories will be reassuring.

Inclusion of daily 1oz(30g) handfuls of peanuts within a moderate fat diet can be recommended as a useful means not only to improve diet quality but also to assist with weight management, due to their satiating effects.

This paper will be useful to health professionals and educators by highlighting how a convenient snack food, peanuts can play a beneficial role within a healthy diet for both cardiovascular protection and weight management.

The purpose of this paper is to evaluate Feel WonderFull Fitness (FWF), a program adhering to the Health At Every SizeTM (HAES) paradigm, on larger women's physical activity and psychosocial health. FWF was tailored to overcome barriers based on weight bias.

The study compared “overweight” and “obese” women in FWF to those not currently enrolled in formal exercise programs. Controls were divided into low physical activity (LPA) and moderate physical activity (MPA) conditions based on pretest exercise level. Outcome measures were collected at pretest and three months later at posttest.

FWF participants had the greatest gains in physical activity and demonstrated significantly greater improvements in depression than the LPA group. FWF and the MPA group showed more improved scores on perceived body attractiveness than the LPA group. Scores on an eating disorders measure improved for all groups, but somewhat more so for the FWF group. Improvements occurred in the absence of weight loss or decreases in body mass index and body fat percentage.

The study was based on a small, homogenous sample using a quasi-experimental design.

The study illustrates HAES strategies that practitioners might incorporate into various health and fitness settings.

The study highlights weight bias as a social justice issue and as a barrier to physical activity participation for larger women.

The study adds to a growing body of literature evaluating HAES approaches, with HAES representing a novel alternative to weight-loss interventions for improving psychosocial health among larger women. It also contributes to the literature on weight bias that has been understudied relative to bias based on other areas of difference.

In recent years, fire accidents in engineering structures have often been reported worldwide, leading to a severe risk to life and property safety. The present study is carried out to evaluate the performance of Ground Granulated Blast Furnace Slag (GGBS) and fly ash–blended laterized mortars at elevated temperatures.

This test program includes the replacement of natural river sand with lateritic fine aggregates (lateritic FA) in terms of 0, 50 and 100%. Also, the ordinary Portland cement (OPC) was replaced with fly ash and GGBS in terms of 10, 20, 30% and 20, 40 and 60%, respectively, for producing blended mortars.

This paper presents results related to the determination of residual compressive strengths of lateritic fine aggregates-based cement mortars with part replacement of cement by fly ash and GGBS exposed to elevated temperatures. The effect of elevated temperatures on the physical and mechanical properties was evaluated with the help of microstructure studies and the quantification of hydration products.

A sustainable cement mortar was produced by replacing natural river sand with lateritic fine aggregates. The thermal strength deterioration features were assessed by exposing the control specimens and lateritic fine aggregates-based cement mortars to elevated temperatures. Changes in the mechanical properties were evaluated through a quantitative microstructure study using scanning electron microscopy (SEM) images. The phase change of hydration products after exposure to elevated temperatures was qualitatively analyzed by greyscale thresholding of SEM images using Image J software.

The paper aims to describe the Taguchi design method-based abrasive wear modeling of in situ AlB2 flake reinforced Al-4Cu matrix alloy composites.

The abrasive wear behaviors of the composite samples were investigated using pin-on-disk method where the samples slid against different sizes of SiC abrasive grits under various testing conditions. The orthogonal array, signal-to-noise (S/N) ratio and analysis of variance were used to study the optimal testing parameters on composite samples.

The weight loss of composites decreased with increasing grit size and percentage reinforcement and increased with increasing sliding speed. The optimum test condition, at which the minimum weight loss is obtained, has been determined to be A3B3C1 levels of the control factors. Deviations between the actual and the predicted S/N ratios for abrasive weight losses are negligibly small with 99.5 per cent confidence level.

This paper fulfils an identification of Taguchi method-based abrasive wear behavior of AlB2/Al-4Cu metal matrix composites produced by squeeze casting under various testing conditions.