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The purpose of this paper is to introduce the RWTH's total artificial heart, ReinHeart, focusing on the design of the unique drive system.

The force characteristics of the drive have been simulated in a finite element (FE) approach. Additionally the coppler losses within the motor coils have been predicted based on the FE‐simulation. Both results are compared to laboratory measurements of a prototype to validate the design.

The presented results show a good correlation between simulation and measurement and proof the applicability of the new design drive system.

The used hydraulic models of the cardiovasular system used as a load for the device are not fully validated with data from living organisms. Therefore, further in vivo trials are needed.

The high force density of the drive allows its integration into a fully implantable, total artificial heart, in order to significantly improve durability. This hopefully will extend the indication for artificial hearts as alternatives to transplantation.

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.

Studies problems related to modelling, control and monitoring of circulatory systems with an artificial heart. First, presents a pulsatile model of cardiovascular systems. This model has a well‐grounded physiological basis and includes several reflex control systems, such as baroreceptor feedback loops, and nonlinearities of vessel compliance, which are inherent in the body. In addition, develops a model of an artificial heart. Based on these models, proposes a pulse frequency modulated (PFM) control scheme for the circulatory systems with an artificial heart. This scheme enables us to regulate the blood pressure and volume of the circulatory systems properly. To monitor the behaviour of the circulatory systems with an artificial heart an observation scheme is finally presented, with which the blood pressure and stroke volumes of the circulatory system can be estimated by using only the measurements of the driving pressure of the artificial heart.

The purpose of this paper is to investigate the numerical fluid-structure interaction (FSI) framework for the simulations of mechanical behavior of new vortex generators (VGs) in smooth wavy fin-and-elliptical tube (SWFET) heat exchanger using the ANSYS MFX Multi-field® solver.

A three-dimensional FSI approach is proposed in this paper to provide better understanding of the performance of the VG structures in SWFET heat exchangers associated with the alloy material properties and geometric factors. The Reynolds-averaged Navier-Stokes equations with shear stress transport turbulence model are applied for modeling of the turbulent flow in SWFET heat exchanger and the linear elastic Cauchy-Navier model is solved for the structural von Mises stress and elastic strain analysis in the VGs region.

Parametric studies conducted in the course of this research successfully identified illustrate that the maximum magnitude of von Mises stress and elastic strain occurs at the root of the VGs and depends on geometrical parameters and material types. These results reveal that the titanium alloy VGs shows a slightly higher strength and lower elastic strain compared to the aluminum alloy VGs.

This paper is one of the first in the literature that provides original information mechanical behavior of a SWFET heat exchanger model with new VGs in the field of FSI coupling technique.

The purpose of this paper is to describe a design process for a drive of a ventricular assist device (VAD) under the consideration of constraints given by the application. In this case, these constraints are the possibility to implant the VAD system, providing a sufficient perfusion of the human body and cutting down development costs.

In the described approach an optimization algorithm is integrated in the initial stage of the design process for a drive system.

During simulations the optimum drive design under the implantation constraints of the given VAD system is found. The key constraints of this design, which are torque, axial force and losses, are validated during initial test bench measurements of a drive prototype.

The described design process enables an optimum drive design from the beginning of a VAD development. This reduces the time to initial and chronic in vivo test, which are required to be approved for the market later. Therefore, this approach cuts development and device costs. Additionally, this design process can be transferred for the design of other drive concepts and applications.

The developed and proved method in this paper enables a competitive and reliable drive design.

The purpose of this study was to fabricate silicone products that had different hardnesses and moduli, thus partially addressing the limitations of homogeneous materials whose deformation depends on altered structure or dimensions, and to provide new dimensions for the design of silicone soft structures.

A soft material three-dimensional printing platform with a dual-channel printing capability was designed and built. Using the material extrusion method, material screening was first performed using single-channel printing, followed by dual-channel-regulated printing experiments on products having different hardness and modulus values.

The proportion of additives has an effect on the accuracy of the printed product. Material screening revealed that Sylgard 527 and SE 1700 could be printed without additives. The hardness and mechanical properties of products are related to the percentage in their composition of hard and soft materials. The hardness of the products could be adjusted from 26A to 42A and the Young’s modulus from 0.875 to 2.378 Mpa.

Existing silicone products molded by casting or printing are mostly composed of a single material, whose uniform hardness and modulus cannot meet the demand for differentiated deformation in the structure. The existing multihardness silicone material printing method has the problems of long material mixing time and slow hardness switching and complicated multi-extrusion head switching. In this study, a simple, low-cost and responsive material extrusion-based hardness programmable preparation method for silicone materials is proposed.

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE) applications in different fields of biomechanics between 1976 and 1991. The aim of this paper is to help the users of FE and BE techniques to get better value from a large collection of papers on the subjects. Categories in biomechanics included in this survey are: orthopaedic mechanics, dental mechanics, cardiovascular mechanics, soft tissue mechanics, biological flow, impact injury, and other fields of applications. More than 900 references are listed.

Purpose: Evidence of adverse health effects of artificial trans fatty acids (TFAs) have accumulated since 1990s, yet TFAs are widely used by several food manufacturers around the world. This review aimed to: ascertain the available evidence of the known unfavourable biochemical properties of artificial TFAs, their metabolic functions and health consequences; estimate their average intake levels and trends in different countries in order to critically evaluate whether more action is required to eliminate them from the diet. Methodology: The published evidence was searched by employing: Medline, Pubmed, InterScience, BioMed Central and Annual Reviews. Findings: With reference to human health, evidences from epidemiological, retrospective and observational studies revealed that the consumption of TFAs could outweigh the health risks posed by saturated fat consumption. The main health concerns included unfavourably altered blood cholesterol concentrations, insulin resistance, foetal brain and neural disturbances, proinflammatory and carcinogenic responses. Great variation exists in the global trends of industrial TFAs intake, being low in Mediterranean region, Japan and Scandinavia and high in parts of United States of America and Iceland. Besides the intense use of TFAs by food manufacturers and in eateries, the use of TFAs in food products is often poorly regulated and ill‐informed to consumers. Value: Since competitive alternatives to TFAs have made them non‐mandatory a broad public health intervention at government level to regulate or completely eliminate them from the national diet is warranted.

The Report of the Royal College of Physicians (London) and the British Cardiac Society issued in April last was the product of a joint working party, whose aim was to formulate the best possible advice which can at present be given to medical practitioners towards the prevention of coronary heart disease. It caused quite a stir, particularly its dietary recommendations, and the mass media made the most of it, more from inferences drawn from the measures recommended than from the report itself. Now that the sensation of it has gone and the dust has begun to settle, we can see the Report contains nothing that is new; it tells us what we have long known. Like the Horsemen of the Apocalypse, except that there are three of them, at least for the moment, the causative factors of the rising incidence of coronary heart disease, built into our affluent society, have been working their way at the heart of man for a good many years now.

The earliest law of the adulteration of food imposed divisions among the local authorities of the day in functions and enforcements; most of the urban and rural sanitary authorities possessed no power under the law. Provisions dealing with unfit food — diseased, unsound, unwholesome or unfit for human food — were not in the first sale of food and drugs measure and there duties were wholly discharged by all local authorities. Rural sanitary authorities were excluded from food and drugs law and boroughs and urban authorities severly restricted. Enforcement in the rural areas was by the county council, although local officers were empowered to take samples of food and submit them for analysis to the public analyst. Power to appoint the public analyst for the area was the main criterion of a “food and drugs authority”. The Minister had power to direct an authority with a population of less than 40,000 but more than 20,000 to enforce the law of adulteration.