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Mechanical circulatory support (MCS) devices can bridge the gap to transplant whilst awaiting a viable donor heart. The Realheart Total Artificial Heart is a novel positive-displacement MCS that generates pulsatile flow via bileaflet mechanical valves. This study developed a combined computational fluid dynamics and fluid-structure interaction (FSI) methodology for simulating positive displacement bileaflet valves. Overset meshing discretised the fluid domain, and a blended weak-strong coupling FSI algorithm was combined with variable time-stepping. Four operating conditions of relevant stroke lengths and rates were assessed. The results demonstrated this modelling strategy is stable and efficient for modelling positive-displacement artificial hearts. [ABSTRACT FROM AUTHOR]

Objective: To define the cellular basis for immune enhancement by a probiotic lactic acid bacteria strain (Bifidobacterium lactis HN019); and to determine whether immune enhancement can be optimized by delivery in oligosaccharide-enriched low-fat milk. Design: A double-blind, three-stage before-and-after intervention trial. Setting: Taipei Medical College Hospital, Taipei, Taiwan. Subjects: Fifty healthy Taiwanese citizens (age range 41-81; median 60) randomly allocated to two groups. Interventions: In stage 1 (run-in control stage) all subjects consumed reconstituted low-fat milk (LFM) for 3 weeks; in stage 2 (probiotic intervention) subjects consumed B. lactis in LFM (group A) or B. lactis in lactose-hydrolysed LFM (group B) for 3 weeks; in stage 3 all subjects returned to non-supplemented LFM for a further 3 weeks (washout stage). The innate immune functions of two different leucocyte types (polymorphonuclear (PMN) cells and natural killer (NK) cells) were assessed at four time points via in vitro analyses on peripheral blood samples. Results: While consumption of LFM alone had no significant effect on immune responses, stage 2 results indicated significantly enhanced PMN cell phagocytosis and NK cell tumour killing activity following consumption of milk containing B. lactis. These increases levelled off following cessation of B. lactis consumption, but remained above the pre-treatment values. Increases in PMN and NK cell activity were greatest among subjects who consumed B. lactis in lactose-hydrolysed LFM. Conclusions: Dietary consumption of the probiotic bacterium B. lactis HN019 enhanced immune function of two different types of leucocytes; the degree of enhancement was increased by consuming B. lactis in an oligosaccharide-rich substrate. Sponsorship: Financial support was provided by the New Zealand Dairy Board. Descriptors: Bifidobacterium lactis; LAB; probiotic; PMN cells; phagocytosis; NK cells, Introduction Lactic acid bacteria (LAB) are common and natural inhabitants of the human gut microflora. LAB are also abundant in fermented food products, especially dairy products such as yoghurt and [...]

Objective: To determine the effects of dietary consumption of Bifidobacterium lactis (strain HN019, DR10[TM] on natural immunity. Design: A randomized, double blind, placebo-controlled clinical trial. Setting:: Janeway Medical Centre, Memorial University, St Johns, Newfoundland. Subjects: Twenty-five healthy elderly volunteers (median age 69 y; range 60-83 y). Interventions: Twelve control subjects consumed 180 ml low-fat/low-lactose milk twice daily for a period of 6 weeks; 13 test subjects consumed milk supplemented with 1.5 x [10.sup.11] colony-forming units of B. lactis twice daily. Indices of natural immunity, including interferon production, phagocytic capacity and phagocyte-mediated bactericidal activity, were determined via peripheral blood at 0, 3, 6 and 12 weeks post-trial commencement. Results: Subjects who consumed milk containing B. lactis for 6 weeks produced significantly enhanced levels of interferon-alpha, upon stimulation of their peripheral blood mononuclear cells in culture, in comparison to the placebo control group who received milk alone. There were also significant increases in polymorphonuclear cell phagocytic capacity among test group subjects, following consumption of milk supplemented with B. lactis, while individuals who consumed B. lactis-supplemented milk or milk alone showed enhanced phagocyte-mediated bactericidal activity. Conclusions: The results demonstrate that dietary consumption of B. lactis HN019 can enhance natural immunity in healthy elderly subjects, and that a relatively short-term dietary regime (6 weeks) is sufficient to impart measurable improvements in immunity that may offer significant health benefits to consumers. Sponsors: Financial support for this project was provided by the New Zealand Dairy Board. Descriptors: Bifidobacterium lactis; LAB; natural immunity; interferon-alpha; phagocytosis; health; elderly, Introduction Lactic acid bacteria (LAB) are among the most numerous of the commensal microflora inhabiting the human large intestine. LAB are generally thought to play an important role in the [...]

This paper describes a digital technique for protecting power transformers. The technique uses positive- and negative-sequence models of the power system in a fault-detection algorithm. While phase voltages and currents at the transformer terminals are used to detect fault, no information concerning parameters of the transformer and power system is required. The performance of the proposed technique was studied for a variety of operating conditions using data generated by emtp simulations. The impact of ratio-mismatch and saturation of cts on the performance of the technique was also examined. Results indicate that the proposed technique is stable during these conditions. Keywords: Power transformer, Current transformer saturation, Differential protection, Microprocessor-based relays.

Teleost fish, Pseudogobius olorum in Swan Estuary, Western Australia, spawn both in spring and autumn, and the biannual spawning is probably due to an increase in water temperature over the last few thousand years. The progeny of the spring-spawning group spawn in the next autumn and those of the autumn-spawning group spawn in the following spring. Growth of the spring progeny is quick between late spring and mid-autumn, and that of the autumn progeny is slow during winter and fast during spring.