15,438 research outputs found
Utilisation of intensive foraging zones by female Australian fur seals.
Within a heterogeneous environment, animals must efficiently locate and utilise foraging patches. One way animals can achieve this is by increasing residency times in areas where foraging success is highest (area-restricted search). For air-breathing diving predators, increased patch residency times can be achieved by altering both surface movements and diving patterns. The current study aimed to spatially identify the areas where female Australian fur seals allocated the most foraging effort, while simultaneously determining the behavioural changes that occur when they increase their foraging intensity. To achieve this, foraging behaviour was successfully recorded with a FastLoc GPS logger and dive behaviour recorder from 29 individual females provisioning pups. Females travelled an average of 118 ± 50 km from their colony during foraging trips that lasted 7.3 ± 3.4 days. Comparison of two methods for calculating foraging intensity (first-passage time and first-passage time modified to include diving behaviour) determined that, due to extended surface intervals where individuals did not travel, inclusion of diving behaviour into foraging analyses was important for this species. Foraging intensity 'hot spots' were found to exist in a mosaic of patches within the Bass Basin, primarily to the south-west of the colony. However, the composition of benthic habitat being targeted remains unclear. When increasing their foraging intensity, individuals tended to perform dives around 148 s or greater, with descent/ascent rates of approximately 1.9 m•s-1 or greater and reduced postdive durations. This suggests individuals were maximising their time within the benthic foraging zone. Furthermore, individuals increased tortuosity and decreased travel speeds while at the surface to maximise their time within a foraging location. These results suggest Australian fur seals will modify both surface movements and diving behaviour to maximise their time within a foraging patch
On a generalization of the seating couples problem
We prove a conjecture of Adamaszek generalizing the seating couples problem
to the case of seats. Concretely, we prove that given a positive integer
and we can partition
into pairs with differences .Comment: 3 page
Renal Function in Suckling and Fasting Pups of the Northern Elephant Seal
Elephant seals fast for prolonged periods without access to water. This is made possible, in part, by reductions in urine production. However, the mechanisms involved in reducing urine production are not understood. In this study, glomerular filtration rate (GFR) was measured in five northern elephant seal pups (Mirounga angustirostris) via the inulin clearance technique. Measurements were made during day 9 and day 18–22 of nursing and the second and eighth week of the postweaning fast. Plasma aldosterone and cortisol concentrations, quantified by radioimmunoassay, were measured in eight other weanlings during the second and eighth week of the fast. Mean GFR was 79.3±29.3 ml/min during the early suckling period and 78.2±17.1, 89.8±52.7, and 80.4±12.2 ml/min during the late suckling, early fasting and late fasting periods, respectively. Differences between nursing and fasting were insignificant, possibly because reduced protein oxidation during suckling and rapid recruitment of protein for tissue synthesis obviated the need for postprandial hyperfiltration. Alternatively, maintenance of GFR during fasting may facilitate urea concentration by compensating for reductions in the fractional excretion of urea. It is further hypothesized that aldosterone is primarily responsible for mediating renal water reabsorption in this system
Hormone and Metabolite Changes associated with Extended Breeding Fasts in Male Northern Elephant Seals (Mirounga Angustirostris)
We measured metabolic hormones and several key metabolites in breeding adult male northern elephant seals to examine the regulation of fuel metabolism during extended natural fasts of over 3 months associated with high levels of energy expenditure. Males were sampled twice, early and late in the fast, losing an average of 23% of body mass and 47% of adipose stores between measurements. Males exhibited metabolic homeostasis over the breeding fast with no changes in glucose, non-esterified fatty acids, or blood urea nitrogen. Ketoacids increased over the fast but were very low when compared to other fasting species. Changes within individuals in total triiodothyronine (tT3) were positively related to daily energy expenditure (DEE) and protein catabolism. Differences in levels of thyroid hormones relative to that observed in weaned pups and females suggest a greater deiodination of T4 to support the high DEE of breeding males. Relative levels of leptin and ghrelin were consistent with the suppression of appetite but a significant reduction in growth hormone across the fast was contrary to expectation in fasting mammals. The lack of the increase in cortisol during fasting found in conspecific weaned pups and lactating females may contribute to the ability of breeding males to spare protein despite high levels of energy expenditure. Together these findings reveal significant differences with conspecifics under varying nutrient demands, suggesting metabolic adaptation to extended high energy fasts
Conforming finite elements with embedded strong discontinuities
A kinematically consistent approach for embedded discontinuitie
A eficácia e segurança da fisioterapia respiratória no tratamento da bronquiolite aguda em crianças até 2 anos de idade: revisão sistemática
Contexto: a bronquiolite aguda é a principal patologia a afectar a criança nos
primeiros 2 anos de vida, a fisioterapia respiratória é uma intervenção
terapêutica utilizada com a intenção de melhorar o curso desta doença
mantendo-se a incerteza sobre a sua eficácia. Objectivo: determinar a eficácia
e segurança da fisioterapia respiratória em crianças com menos de 2 anos com
bronquiolite aguda. Fontes de Informação: Medline (1966 a Agosto 2010),
EMBASE(1990 a Agosto 2010), Pedro e Lilacs (1982 a Agosto 2010). Outra
fonte de informação incluiu a bibliografia dos estudos obtidos. Selecção de
estudos: estudos experimentais comparando a fisioterapia respiratória com
cuidados habituais, em crianças com menos de 2 anos e bronquiolite aguda,
em ventilação espontânea, em qualquer contexto. Estudos pré-experimentais
ou observacionais com os mesmos participantes e intervenções foram
admitidos complementarmente aos experimentais. Extracção de dados e
análise: um investigador extraiu os dados dos artigos obtidos e avaliou o risco
de viés. A eficácia e segurança da fisioterapia respiratória foram determinadas
pelos seguintes outcomes: duração do internamento hospitalar ou do evento,
variação de scores de severidade clÃnica, saturação periférica e suplementação
de oxigénio, recidivas, recurso a antibióticos e efeitos deletérios ou
deterioração clÃnica reportada. SÃntese de dados: 6 estudos experimentais
foram admitidos. As suas amostras provinham de criança internadas em
hospital. As técnicas de fisioterapia respiratória foram comparadas com
cuidados habituais. Nenhum estudo evidenciou melhoria dos outcomes de
interesse na comparação entre grupos, excepto avaliações de curta duração da
saturação periférica de oxigénio e scores de severidade clÃnica. 1 estudo
reportou uma percentagem significativamente maior no grupo submetido a
fisioterapia respiratória de crianças que vomitaram, tiveram uma
desestabilização respiratória transitória, e na percepção de stress da criança
pelos cuidadores. São relatadas ainda fracturas costais a causa de fisioterapia
respiratória. Limitações: o risco de viés era alto em 2 estudos, baixo num
estudo e indeterminado nos restantes. Conclusões: aparentemente a
fisioterapia respiratória não é eficaz e pode produzir efeitos deletérios
importantes, mas a evidência é pobre, carecendo de novos estudos.Context: acute bronchiolitis is the leading pathology affecting children in their
first 2 years of life, respiratory physiotherapy is used to treat acute bronchiolitis
but the effectiveness of this intervention remains unclear.
Objective: to determine the effectiveness and safety of respiratory
physiotherapy in infants aged less than 2 years old with acute bronchiolitis
Information Sources: Medline (1966 to August 2010), EMBASE (1990 to August
2010), Pedro and Lilacs (1982 to August 2010). Other source included
bibliography of the included studies.
Study selection: randomized controlled trials in which respiratory physiotherapy
was compared against usual care. Additionally observational or randomized
trials were included to improve this data for this review.
Data extraction and analysis: one researcher extracted the data from the
retrieved studies and evaluated their risk of bias. To assess the effectiveness
and safety of respiratory physiotherapy the following outcomes were used:
length of disease or hospital stay, clinical scoring variation, oxygen saturation,
oxygen supplementation, relapses, antibiotics usage or clinical deterioration
caused by respiratory physiotherapy.
Results: 6 randomized controlled trials were retrieved. Respiratory
physiotherapy was compared with standard care in children admitted to the
hospital. Apart from short term measurements of oxygen saturation and clinical
scoring variation, no differences were found between respiratory physiotherapy
and usual care. 1 study showed a higher proportion of vomiting, transient
respiratory distress and caregivers’ perception of child’ stress in the intervention
group compared to the control group. Rib fractures caused by respiratory
physiotherapy were also reported in observational studies.
Limitations: 2 studies had high risk of bias, 1 study had low risk of bias and the
risk of bias in the remaining studies was unclear.
Conclusion: respiratory physiotherapy appears to be ineffective and may have
some harmful effects, but the papers retrieved were poor, as a result, the
effectiveness and safety of respiratory physiotherapy should be further
investigated
Congress should vote against overturning an updated rule that protects farmworkers from being underpaid
The Congressional Review Act (CRA) is a law that gives members of Congress the ability to pass resolutions to overturn many rules and regulations made by federal agencies. As early as this week, members of Congress are likely to begin voting on a resolution to derail a wage rule for migrant farmworkers in the H-2A visa program that was recently updated by the U.S. Department of Labor, known as the Adverse Effect Wage Rate (AEWR).The intent of the AEWR is to protect wages and working conditions for all farmworkers and prevent farm employers from using the H-2A visa program as a loophole to underpay their workers. A vote to rescind the AEWR would be a terrible outcome. Why? It will hurt the farmworkers that help put food on all our tables by cutting their pay—even though most already earn very low wages, and many are living in poverty
- …