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Extending the time range of apatite (U-Th)/He thermochronometry in slowly cooled terranes: Palaeozoic to Cenozoic exhumation history of southeast Sweden

The use of (U-Th)/He thermochronometry in old slowly cooled terranes has long been debated. Hence, studies of natural setting are needed to verify the expected diffusivity behaviour of helium. Our results demonstrate that the (U-Th)/He method can be applicable to samples older than 200 Ma, and that available helium diffusion models can reproduce the results obtained from the age-vs.-depth trends.

Actions seen as demanding in patients with severe dementia during one year of intervention. Comparison with controls

Behaviours, viewed by nurses as demanding, performed by patients with severe dementia were investigated during one year of intervention. Supervised implementation of individually planned care and systematic clinical supervision were implemented on one experimental ward (EW) while another ward (CW) served as control. Each ward had 11 patients. At baseline and after 6 and 12 months of intervention s

Similitude of permeabilities for Ficoll, pullulan, charge-modified albumin and native albumin across the rat peritoneal membrane.

Abstract Aim: Compared to neutral globular proteins, neutral polysaccharides, such as dextran, pullulan and Ficoll, appear hyperpermeable across the glomerular filtration barrier. This has been attributed to an increased flexibility and/or asymmetry of polysaccharides. The present study investigates whether polysaccharides are hyperpermeable also across the continuous capillaries in the rat perito

Do adult and juvenile dunlins Calidris alpina form randomly mixed flocks during fall migration?

Many northerly breeding shorebird species show a separation in timing of adult and juvenile migration. If, in addition to genetic control of migration, learning from experienced conspecifics is advantageous, juveniles should join adult birds during their first fall migration when possible. We here present a method to test if juveniles mix with adults during the period of overlap during southward m

The near and far wake of Pallas' long tongued bat (Glossophaga soricina).

The wake structures of a bat in flight have a number of characteristics not associated with any of the bird species studied to this point. Unique features include discrete vortex rings generating negative lift at the end of the upstroke at medium and high speeds, each wing generating its own vortex loop, and a systematic variation in the circulation of the start and stop vortices along the wingspa

Devazepide-induced hyperplasia in the rat liver and bile ducts

Cholecystokinin (CCK) is a potent stimulus of pancreatic enzyme secretion and growth and is known to influence the flow of biliary secretions. It has also been suggested as a trophic stimulus of the biliary tract and liver, but confirmatory studies are lacking. The aim of the present experiment was to study the effects on the rat liver and biliary tract of long-term stimulation of CCK-8S and the C

Relationship of the Hormone-Sensitive Lipase-Mediated Modulation of Cholesterol Metabolism in Individual Compartments of the Testis to Serum Pituitary Hormone and Testosterone Concentrations in a Seasonal Breeder, the Mink (Mustela vison).

The role of cholesterol differs in the two compartments of the testis. In the interstitial tissue, cholesterol is necessary for the synthesis of testosterone, whereas in the seminiferous tubules, membrane cholesterol content in developing germ cells will influence the gametes' fertility. Here we evaluate the hormone-sensitive lipase (HSL) modulation of the cholesterol metabolism in each compartmen

Nitric oxide produced in response to engagement of beta 2 integrins on human neutrophils activates the monomeric GTPases Rap1 and Rap2 and promotes adhesion

We found that engagement of beta 2 integrins on human neutrophils increased the levels of GTP-bound Rap1 and Rap2. Also, the activation of Rap1 was blocked by PP1, SU6656, LY294002, GF109203X, or BAPTA-AM, which indicates that the downstream signaling events in Rap1 activation involve Src tyrosine kinases, phosphoinositide 3-kinase, protein kinase C, and release of calcium. Surprisingly, the beta

Coping after trans-femoral amputation due to trauma or tumour--a phenomenological approach.

Purpose: To describe, by use of a phenomenological approach, how relatively young trans-femoral amputees experienced their amputation and their coping strategies in the acute phase and over time. Method: Eleven trans-femoral amputees, median age 33.5 years, were interviewed. The amputation was caused by tumour, motorcycle accidents or work-related traumas. Amputation was made in median 7.5 years

Obstetric adversity and age at first presentation with schizophrenia: Evidence of a dose-response relationship

Objective: The purpose of the study was to determine if a dose-response relationship exists between obstetric adversity and age at first presentation with schizophrenia. Method: The Dublin Psychiatric Case Register was used to identify subjects with schizophrenia. Data on obstetric complications, social class of origin, and family history of psychiatric illness were obtained for those subjects. Re

Primary and secondary phenology. Does it pay a frog to breed early?

This study examines the consequences of variation in the laying and hatching date for the time of metamorphosis in the common frog Rana temporaria. Field data are presented showing that eggs laid early tend to take longer to develop. Thus, the time advantage for early eggs is reduced at the time of hatching. There was an among-year variation in this phenomenon; it was not manifest in a phenologica

Perturbed partners: opposite responses of plant and animal mutualist guilds to inundation disturbances

Mutualists have been suggested to play an important role in the assembly of many plant and animal communities, but it is not clear how this depends on environmental factors. Do, for instance, natural disturbances increase or decrease the role of mutualism? We focused on entire guilds of mutualists, studying seed-dispersing ants and ant-dispersed plants along gradients of inundation disturbances. W

Telomere-associated repeats in Chironomus form discrete subfamilies generated by gene conversion

In dipteran insects the most distal telomere-associated DNA known to exist consists of long, complex tandem repeats. We have classified the 340-bp tandemly arranged repeats in Chironomus pallidivittatus. The repeats are distributed in a small number of subfamilies. One type of the repeat has the character of a master unit from which other main units can be derived usually by simple changes. The de

Field effect studies on rubrene and impurities of rubrene

Rubrene single crystals have been grown by a vapor-phase process. Two additional compounds that contaminate rubrene have been identified and their structures determined. Single crystals of rubrene show excellent crystallinity and very small rocking curve width. Field effect transistors based on pure rubrene single crystals with colloidal graphite electrodes and Parylene as a dielectric demonstrate

Good urodynamic practices: uroflowmetry, filling cystometry, and pressure-flow studies

This is the first report of the International Continence Society (ICS) on the development of comprehensive guidelines for Good Urodynamic Practice for the measurement, quality control, and documentation of urodynamic investigations in both clinical and research environments. This report focuses on the most common urodynamics examinations; uroflowmetry, pressure recording during filling cystometry,

An IEC 62061 compliant safety system design method for machinery

The purpose of safety systems is to reduce dangers to human life or environment to acceptable levels. In order to aid companies in this when developing safety systems for functional safety of machinery, the standard IEC 62061 has recently been released. The standard proposes an outlined design method to follow requirements specification. However, companies that use the standard have to implement a