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Heat transfer and turbulent flow characteristics over pocket cavity in the junction part of an outlet guide vane in a gas turbine

A pocket cavity is generated when the Low Pressure Turbine (LPT) is connected to the Outlet Guide Vane (OGV) in the rear part of a gas turbine engine due to the different conjugate diameters. This kind of pocket cavities, due to the high Reynolds number and the specific shapes, are hardly investigated in previous researches. The heat transfer distribution and fluid flow over the pocket cavity have

Intersexual competition in a polygynous mating system

In the facultatively polygynous European starling (Sturnus vulgaris) males attract from one to four mates. Males gain by mating polygynously because they produce more offspring by doing so. This is true also genetically, since polygynous males on average father the same proportion of offspring as monogamous males. However, the marginal benefit of attracting additional mates is negatively affected

Changes of community composition at multiple trophic levels due to hunting in Nigerian tropical forest

Hunting in tropical forests decimates large mammals, and this may have direct and indirect effects on other trophic levels and lead to trophic cascades. We compared replicated sites of hunted and protected forests in southeastern Nigeria, with respect to community composition of primates, other mammals, birds, plant seedlings, and mature trees. We make predictions regarding the community compositi

Psychometric analysis of the Salutogenic Health Indicator Scale (SHIS) in adolescents

Aim: The aim of this study was to test the psychometric properties of the Salutogenic Health Indicator Scale (SHIS) in an adolescent population. Methods: The investigation was performed among Swedish students aged 13-15 years (n = 817; 58% girls). The SHIS was assessed for respondent acceptability, and its psychometric properties were evaluated according to classical test theory (regarding unidime

Friendship trust and psychological well-being from late adolescence to early adulthood : A structural equation modelling approach

Aims: This study explored the sex-specific associations between friendship trust and the psychological well-being of young Swedes from late adolescence to early adulthood. Methods: A random sample of native Swedes born in 1990 was surveyed at age 19 years and again at age 23 years regarding their own well-being and their relationships with a maximum of five self-named peers. The response rate was

Time to amyloid positivity and preclinical changes in brain metabolism, atrophy, and cognition : Evidence for emerging amyloid pathology in alzheimer's disease

Background: Aβ pathology is associated with longitudinal changes of brain metabolism, atrophy, and cognition, in cognitively healthy elders. However, Aβ information is usually measured cross-sectionally and dichotomized to classify subjects as Aβ-positive or Aβ-negative, making it difficult to evaluate when brain and cognitive changes occur with respect to emerging Aβ pathology. In this study, we

NOx-Conversion and Activation Temperature of a SCR-Catalyst Whilst Using a Novel Biomimetic Flash-Boiling AdBlue Injector on a LD Engine

Yearly 3.3 million premature deaths occur worldwide due to air pollution and NOx pollution counts for nearly one seventh of those [1]. This makes exhaust after-treatment a very important research and has caused the permitted emission levels for NOx to decrease to very low levels, for EURO 6 only 0.4 g/kWh. Recently new legislation on ammonia slip with a limit of 10 ppm NH3 has been added [2], whic

Potential for irradiation of methane to form complex organic molecules in impact craters : Implications for Mars, Titan and Europa

The release of methane from crater sites following meteorite impact is a possible consequence of the thermal alteration of organic matter, or tapping of reservoired gas of biogenic or abiogenic origin. At least the latter is feasible on Mars. Methane and higher hydrocarbons are susceptible to polymerization and precipitation by radioactive minerals. Where such minerals are present in impact target

Severity of mild cognitive impairment in early Parkinson's disease contributes to poorer quality of life

BACKGROUND: Poor quality of life (QoL) is a feature of people with Parkinson's disease (PD) who develop dementia. The relationship between mild cognitive impairment in PD (PD-MCI) and QoL is less clear. To address this, we studied the impact of varying severities of cognitive impairment on QoL in a cohort of non-demented patients with early PD.METHOD: Patients with newly diagnosed PD (n = 219) and

Time course of dopamine neuron loss and glial response in the 6-OHDA striatal mouse model of Parkinson's disease

The 6-hydroxydopamine (6-OHDA) neurotoxic lesion of the midbrain dopamine (DA) system is one of the most widely used techniques for modelling Parkinson's disease in rodents. The majority of studies using this approach, however, largely limit their analysis to lesioning acutely, and looking at behavioural deficits and the number of surviving tyrosine hydroxylase (TH)-stained cells in the midbrain.