485 research outputs found
Psychotic symptoms in young adults exposed to childhood trauma - A 20 year follow-up study
Full text linkChildhood adversity has been shown to increase the risk of psychotic symptoms in adult life. However, there are no previous studies looking at the association between experiencing a natural disaster during childhood and the development of psychotic symptoms in young adulthood. Eight hundred and six bushfire-exposed children and 725 control children were evaluated following the 1983 South Australian bushfires. Five hundred and twenty nine (65.6%) of the bushfire group and 464 (64%) controls participated in a follow up study 20 years later. Childhood data on emotional and behavioural disorders and dysfunctional parenting was available. The adult assessment included the Australian National Health and Well-Being psychosis screen and detailed information about trauma, childhood adversity and alcohol and cannabis abuse. 5.6% of subjects responded positively to the psychosis screen and 2.6% responded positively to a further probe question. Psychotic symptoms were more common in subjects exposed to a greater number of traumas, and were associated with higher rates of childhood adversity, emotional and behavioural disturbance, dysfunctional parenting, and alcohol and cannabis abuse. Subjects exposed to bushfires as children did not have a greater risk of psychosis. Our results indicate that exposure to multiple traumas, rather than a single major trauma, increases the risk of later psychosis.Cherrie Galletly, Miranda Van Hooff, Alexander McFarlan
Pathways to Care, Mental Health and Wellbeing Study
No full textForbes D, Van Hooff M, Lawrence-Wood E, Sadler N, Hodson S, Benassi H, Hansen C, Avery J, Varker T, O, Donnell M, Phelps A, Frederickson J, Sharp M, Searle A, McFarlane
Mental Health Prevalence and Pathways to Care Summary Report, Mental Health and Wellbeing Study
No full textVan Hooff M, Forbes D, Lawrence-Wood E, Hodson S, Sadler N, Benassi H, Hansen C, Grace B, Avery J, Searle A, Iannos M, Abraham M, Baur J, Varker T, O, Donnell M, Phelps A, Frederickson J, Sharp M, McFarlane
PIV measurements of opposing-jet ventilation flow in a reduced-scale simplified empty airplane cabin
Full text linksponsorship: The Research Foundation - Flanders (FWO) is gratefully ac-knowledged for their financial support of the PhD fellowship of Jo-Hendrik Thysen (project FWO 1150617N) , the post-doctoral fellowship of Twan van Hooff (project FWO 12R9718N) , and the funding for the development of the experimental set-up (FWO 1518517N) . The authors are grateful to Airbus for supporting the measurement campaign. Special thanks go to Jan Diepens, Geert-Jan Maas and Stan van Asten, members of the Laboratory of the Unit Building Physics and Services at Eindhoven University of Technology, and Ad Holten, member of the Laboratory of the Fluids and Flows (F&F) section at Eindhoven University of Technology, for their valuable contributions. (Research Foundation - Flanders (FWO)|FWO 1150617N, Research Foundation - Flanders (FWO)|FWO 12R9718N, Research Foundation - Flanders (FWO)|FWO 1518517N)status: Published onlin
A field study on Sumatran orang utans (Pongo pygmaeus abelii Lesson 1827) : ecology, behaviour and conservation
No full textThe results of a three year research project on the ecology, behaviour and conservation of the Sumatran orang utan are discussed. The 150 hectares Ketambe study area lie within the boundaries of the Gunung Leuser. reserve in Aceh Tenggara, and consists of mixed rainforest typical of hilly regions.The orang utan's food is irregularly distributed in quantity, space and time within this area. Although the orang utan is frugivorous he also eats leaves, insects, 'bark' and several other less important foods, such as bird's eggs. By far the largest part of the 114 food plants collected is typical primary rainforest growth. Figs make up an important part of the diet, particularly those known as the 'strangling' Ficus spp. As the fruiting seasons of the various strangling fig species are staggered over the whole year, and such trees are often enormous in size, they form particularly suitable food sources. Orang utans appear to have a good topographical knowledge of their 'home range'. There are indications that fig trees bearing ripe fruits are sometimes found by using the flight paths of flocks of hornbills, which also feed on figs. With respect to figs in particular, the orang utan must compete for its food with many other species, notably primates.The study area was regularly used by 22 individually recognized orang utans. Both males and females live in homeranges which overlap considerably and are 2-10 km sq. in extent. The population density of the Ketambe area is considerably higher than that reported for other areas in Indonesia, being approximately 5 individuals per square kilometre. Orang utans live a 'limited gregarious' lifestyle, that is, adult males spend the largest part of their time alone, and avoid encounters with other adult males. The adult females and their offspring stay together for the first 4-5 years of life (the birth interval is at least 3 years.). Adolescent social groups form after the mother-offspring bond becomes weaker. This social phase continues for each individual until either (a) the sexual dimorphistic characteristics of males are clearly distinguishable (at approximately 15 years of age), or (b) the female's first young is born (approximately 10 years of age). Adults also have social moments in their lives. Several individuals in an area can come together to form a 'temporary association' in certain fruit trees. It may be seen from their behaviour that they know each other well and that a network of relationships exist which is partly based on competitive dominance. A peaceful co-existence between adult males however, has not been observed; meetings between adult males had invariably an agonistic character. The sexual behaviour of the orang utan is roughly divisable into: (a) 'raping' of some females by sub-adult males; and (b) cooperative matings, where females often take the intitiative by presenting themselves to, usually, adult males. It appears that only the latter makes an essential contribution to reproduction.The social behaviour of the orang utan is considered and described in detail. Comparison of the behavioural repertoire of this species with that of the (gregarious) chimpanzee shows that the two species are closely related. There are clear differences in social organisation, however, which appear to be mainly of degree, rather than of quality. The social organisation of an animal must be a factor that fits its situational (i.e. environmental) context, but is based on phylogenetic characteristics. Comparison of the habitats of these two apes reveals that they both live in a similar ecological condition with respect to food. The reasons for the exceptional life-style on the part of the orang utan are possibly to be found in the predation pressure the species is exposed to, particularly by man. Man has been present in regions of South-EastAsia since the Pleistocene. It is plausible that the orang utan has been persecuted by man continuously from this time. A comparable influence on the chimpanzee is much more recent. The orang utan is the heaviest arboreal creature and has an exceptional social organisation for a primate. If it may be assumed that high intelligence is a biological outcome of complex group life then, on grounds of intelligence, and from the distinct social organisation and current arboreal life-style it maybe postulated that the orang utan has evolved from a groundliving social ape. This original form was supplanted from its niche by a better adapted ground-living social ape, that is, man. It is possible that a stricly arboreal life style for an animal as heavy as an adult orang utan is not compatible with a social life-style. Moreover, it is likely that refraining from a high degree of sociability and inconspicuousness are the best strategies against human predation.Since one possibility is that the hunting pressure in ancient (and current) times had a great influence on the biology of the orang utan, I have paid particular attention to hunting behaviour in hominids. At present, this form of threat is overshadowed by excessive habitat destruction. Cultivation in connection with the explosive population growth in Indonesia, together with the commercial timber concerns, affect the tropical rainforest ecosystem in such proportions that even reserves are threatened. Despite being protected since 1932, the orang utan is a severely endangered species. Rehabilitation of orang utans is a conservation action directed at reducing the still ongoing hunting pressure. This is despite the fact that there are clear risks in this to the wild population. These risks can be negated by confining rehabilitation projects to areas lacking a wild orang utan population.The orang utan is a component of an intact ecosystem and it is of utmost importance that the emphasis of nature conservation schemes is placed on the totality and balance of the tropical rainforest ecosystem. Every form of commercial exploitation within this ecosystem is incompatible with the proposed goal of preserving the system. The removal of components (e.g. 'selective logging' or 'selective hunting') does real damage to the balance of the system.An orang utan who lives in an exploited forest is in principle of equally small biological value as an orang utan in a zoo; it is a, debatably essential, biological solution that does not correspond to the set of conditions originally operating in its natural selection
Cross-ventilation in a generic isolated building equipped with louvers: wind-tunnel experiments and CFD simulations
Full text linkNatural ventilation can be used to improve indoor air quality, remove contaminants from spaces and to remove heat from a building during the day, or during the night. In some cases, openings for natural ventilation are equipped with shading devices – such as louvers – to reduce solar heat gains while allowing natural ventilation. This study presents wind-tunnel experiments and computational fluid dynamics (CFD) simulations of a cross-ventilated building equipped with louvers. Four opening positions are studied: (i) openings in the center, (ii) upper or (iii) lower part of the windward and leeward facades or (iv) one opening in the upper part of the windward facade and one opening in the lower part of the leeward facade. The 3D steady Reynolds-averaged Navier-Stokes (RANS) simulations are performed with three turbulence models (RNG k-ε, SST k-ω, RSM) and validated with the wind-tunnel experiments. The experimental results show that the largest velocities occur in a building with openings in the upper part of the facade. The best agreement with experimental data is provided by RSM. In addition, CFD simulations for buildings without louvers are conducted for the same opening positions to evaluate the effect of louvers on the dimensionless volume flow rate, age of air and air exchange efficiency. The highest dimensionless volume flow rate at reduced scale (0.69) is obtained in the building with louvered openings in the upper part of the facade and the highest air exchange efficiency is achieved for a building with louvered openings in the center of the facade (45%)
De toekomst van flexibele arbeid: hoe flexibel is Nederland?
No full textEen beeld wordt geschetst van hoe werkend Nederland omgaat met flexibiliteit. Flexibiliteit is onontbeerlijk in deze tijd van globalisering en toenemende concurrentie. De vraag is hoe men daar vorm aan kan geven. Aan ondernemers is gevraagd hun eigen beleid terzake onder woorden te brengen. Specifiek is gevraagd naar de rol die zij toebedelen aan flexibele arbeid in de meest brede opvatting en uitzendarbeid in het bijzonder. Desondanks pakken de meesten van hen dit nog vrij traditioneel en op ad hoc-basis op. Een goed doordacht beleid ontbreekt vaak. De plannen voor de toekomst zijn ambitieus, met name de middelgrote bedrijven willen hun flexibele schil sterk uitbreiden. Een externe partner kan goed van pas komen om dit proces in goede banen te leiden. De gepresenteerde resultaten zijn doorspekt met voorbeelden uit de praktijk, waarin vooruitstrevende bedrijven een zeer uitgesproken visie hebben op flexibiliteit binnen hun eigen bedrijf. Ook zijn er sprekende praktijkvoorbeelden opgenomen over strategische samenwerkingverbanden tussen werkgevers en uitzendorganisaties
Ventilatie bij lage luchtsnelheden
No full textGoede ventilatie van gebouwen en vervoersmiddelen is niet alleen van belang voor onze gezondheid en ons comfort, maar ook voor energiezuinigheid en duurzaamheid. Mengventilatie, gebaseerd op de
toevoer van verse lucht bovenin een ruimte, wordt bet meest toegepast (figuur ia en ib). De impuls van de toegevoerde Iucht zorgt ervoor dat de verse lucht zich mengt met de in de ruimte aanwezige lucht, waarna de gemengde lucht wordt afgevoerd. Dat mag een eenvoudig proces Iijken, maar ondanks veel onderzoek, zijn er nog altijd heel wat vragen onbeantwoord
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