Thermal losses in sealed, gas-filled flat plate solar collectors

A sealed space between absorber and cover glass makes it possible reducing the influence of humidity condensate and dust at the same time as the enclosed space can be filled with a suitable gas for lowering the losses. This paper is about the size of the losses in these collectors. A calculating model of a gas-filled flat plate solar collector was built in Matlab with standard heat transfer formulas. It showed that the total loss can be reduced up to 20% when changing to an inert gas. It is also possible using a much shorter distance and still achieve low losses at the same time as the mechanical stresses in the material is reduce.

Life, death, and subjectivity : moral sources in bioethics

"This book presents an exploration of concepts central to health care practice. In exploring such concepts as Subjectivity, Life, Personhood, and Death in deep philosophical terms, the book aims to draw out the ethical demands that arise when we encounter these phenomena, and also the moral resources of health care workers for meeting those demands."--BOOK JACKET.

The sources of stress experienced by professional Australian footballers

Previous studies looking at the sources of stress in sport have generally overlooked the unique experiences of professional athletes participating in team sports. This paper describes the results of a qualitative study aimed at identifying the sources of stress experienced by a cross-section of professional Australian footballers. Players from two Australian Football League clubs took part in the study involving in-depth, one-to-one interviews and focus group discussions. The results revealed that players identified sources of stress that went beyond those associated with the competitive event (such as poor performances) and included a lack of feedback, difficulty balancing football and study commitments, and job insecurity. The influence of both competition and non-competition sources of stress parallels previous research involving non-professional athletes and indicates that the entire sporting experience needs to be taken into account when developing stress management strategies.

Are information sources associated with Australian`s beliefs about the necessity of meat?

The aim of this study was to examine whether use of and trust in health, food, and nutrition information sources are associated with the belief that meat is a necessary dietary component. Over 700 South Australians participated in a questionnaire survey that included questions on frequency of use of and level of trust in information sources, vegetarian status, meat beliefs, and demography. It was found that information sources are associated with the belief that meat is necessary, since they
accounted for over 40% of the variance for all respondents. The most important associations were: lack of use of unorthodox sources; trust in orthodox sources; trust in advertising and the mass media; and trust in and use of social sources. There were differences in which predictors were important, however, depending on the respondent's sex, age, and vegetarian status. The implications of these observed communities of interest for health promotion are discussed.

Two sources of Michael Polanyi`s prototypal notion of incommensurability: Evans-Pritchard on Azande witchcraft and St Augustine on conversion

Michael Polanyi argues in Personal Knowledge (1958) that conceptual frameworks involved in major scientific controversies are separated by a `logical gap'. Such frameworks, according to Polanyi (1958: 151), are logically disconnected: their protagonists think differently, use different languages and occupy different worlds. Relinquishing one framework and adopting another, Polanyi's scientist undergoes a `conversion' to a new `faith'. Polanyi, in other words, presaged Kuhn and Feyerabend's concept of incommensurability. To what influences was Polanyi subject as he developed his concept of the logical gap? The answer, as unfolded in this article, is twofold: Evans-Pritchard's Witchcraft, Oracles and Magic among the Azande and the Confessions of St Augustine.

Sources of doubt, sources of duty: HLA Hart on international law

In many ways HLA Hart’s critical analysis of the concept of law, with its repudiation of simple command theories of legal obligation, is at the same time a critique of the notion of state sovereignty. It is therefore an adumbration, if no more, of a radical reconceptualisation of international law, one which redefines the distinction between municipal and in-ternational jurisdiction. This paper is an exploration of what Hart could or ‘should’ have said about international law, based as much as possible on what he did say about international law and law in general. After some introductory comments it outlines Hart’s general analysis of law, with particular reference to the relevance for our understanding of international law.

The relative absorption of fatty acids in brown trout (Salmo trutta) fed a commercial extruded pellet coated with different lipid sources

The objective of the present study was to investigate the fatty acid absorption capabilities of brown trout (Salmo trutta) fed commercial extruded diets. Five commercial extruded pellets, different only in the lipid sources used for fat coating, were tested on juvenile brown trout for 45 days. The trout were reared in fresh water at 14.6 ± 0.4° C and 7.7 ±
0.3 mg/l, temperature and dissolved oxygen, respectively. The tested lipid sources were fish oil, canola oil, oleine oil, swine fat and poultry fat. After the adaptation period faeces were collected by gently stripping from naesthetized fish. Fatty acid analysis was performed on experimental diets and on collected faeces to evaluate the relative absorption capabilities of the trout digestive system with respect to each detected fatty acid. The use of the relative absorption efficiency (rAE) was opted to evaluate the intrinsic capability of each fatty acid to be absorbed. Brown trout showed a
specific preferential order of absorption of the fatty acids, preferring shorter over longer chain fatty acids and preferring the more unsaturated to the more saturated fatty acids. The fatty acid that showed the best relative absorbability was the C18:4n-3 (rAE = 5.14 ± 0.72), which has a fairly short carbon chain, but at the same time a high unsaturation level, followed by the C18:3n-3 (rAE = 3.38 ± 0.30). The fatty acid that showed the worst relative absorbability (rAE = 0.21 ± 0.02) was C24:1n-9.

A comparison of the sources and nature of body image messages perceived by indigenous Fijian and European Australian adolescent girls

Australian and Fijian adolescent girls reported on the influence that sociocultural factors, including parents, peers, and the media, had on their body image attitudes. It was expected that messages that promote a thin body would be less prevalent among Fijians, as their cultural traditions place more importance on robust body sizes. An inductive thematic analysis of the girls’ semi-structured interviews indicated that both Fijian (n = 16) and Australian (n = 16) girls (aged 13–17) reported messages from similar sources, which included parents, siblings, and friends/peers. Australian girls consistently reported messages that reinforced thinness. On the other hand, Fijian girls reported messages that emphasized both thinness and robustness. The discussion focuses on the conflict between Western ideals and cultural Fijian traditions and the implications for culturally sensitive interventions.

Effects of dietary lipid sources on flavour volatile compounds of brown trout (Salmo trutta L.) fillet

The high cost and unpredictable availability of fish meal and fish oil (FO) forced feed mill companies to look for alternative ingredients for aquafeeds. In this study, the effects of alternative dietary lipid sources [FO as control, canola oil (CO), oleine oil (OO), poultry fat (PF) and pork lard (PL)] in trout feed on flavour volatile compounds occurring in brown trout (Salmo trutta L.) fillet were evaluated after 70 days of feeding (rearing temperature 14.6°C). Total amounts of volatile compounds identified were higher for fillets of fish fed diets containing only FO as lipid sources. Total amount of alcohols and aldehydes of the fillets were linearly directly related to the percentage content of polyunsaturated fatty acids (PUFA) n-3 of brown trout flesh. The use of alternative dietary lipid sources, modifying the fillet fatty acids composition, affect the total amount of volatile compounds and, changing the relative amount of each volatile compound, affect the flavour of the fish flesh.

Effects of alternative dietary lipid sources on performance, tissues chemical composition, mitochondrial fatty acid oxidation capabilities, and sensory characteristics in brown trout (Salmo trutta L.)

The efficiency of five dietary lipid sources (fish oil as control—C; canola oil—CO; poultry fat—PF; pork lard—PL; and oleine oil—OO) were evaluated in juvenile brown trout (58.4±0.7 g) in an experiment conducted over 70 days at 14.6±0.4 °C. The best growth was observed in fish fed the C diet whereas the PL diet fed fish had the best feed utilization. Significant differences in carcass and muscle proximate composition, but not in liver, were noted among fish fed the different dietary treatments. The fatty acid composition of muscle largely reflected that of the diets, while total cholesterol was not affected. The atherogenicity and the thrombogenicity qualities of the trout flesh were modified by the lipid sources. Sensory analysis did not show any significant differences among the cooked fillets with respect to dietary treatments, while in uncooked products, some significant differences were observed. The carnitine palmitoyltransferase I and II (CPT-I and CPT-II) activities of liver and white muscle were assayed for a better understanding of the potential β-oxidation capability of the different dietary lipid sources. The hepatic, but not white muscle CPT-I and CPT-II activities were affected by dietary treatments. This study showed that alternative lipid sources could be used effectively for oil coating extruded diets for brown trout.