Hoarding of pulsed resources : temporal variations in egg-caching by arctic fox

Resource pulses are common in various ecosystems and often have large impacts on ecosystem functioning. Many animals hoard food during resource pulses, yet how this behaviour affects pulse diffusion through trophic levels is poorly known because of a lack of individual-based studies. Our objective was to examine how the hoarding behaviour of arctic foxes (Alopex lagopus) preying on a seasonal pulsed resource (goose eggs) was affected by annual and seasonal changes in resource availability. We monitored foraging behaviour of foxes in a greater snow goose (Chen caerulescens atlanticus) colony during 8 nesting seasons that covered 2 lemming cycles. The number of goose eggs taken and cached per hour by foxes declined 6-fold from laying to hatching, while the proportion of eggs cached remained constant. In contrast, the proportion of eggs cached by foxes fluctuated in response to the annual lemming cycle independently of the seasonal pulse of goose eggs. Foxes cached the majority of eggs taken (> 90%) when lemming abundance was high or moderate but only 40% during the low phase of the cycle. This likely occurred because foxes consumed a greater proportion of goose eggs to fulfill their energy requirement at low lemming abundance. Our study clearly illustrates a behavioural mechanism that extends the energetic benefits of a resource pulse. The hoarding behaviour of the main predator enhances the allochthonous nutrients input brought by migrating birds from the south into the arctic terrestrial ecosystem. This could increase average predator density and promote indirect interactions among prey

Étude de convivialité de l’utilisation d’un agenda électronique par des personnes souffrant de schizophrénie

La schizophrénie est associée à des troubles du fonctionnement mnésique et exécutif qui altèrent la capacité des patients à organiser leurs Activités de la Vie Quotidienne (AVQ). Afin d’améliorer leur autonomie et d’alléger la charge de leurs aidants, nous proposons de programmer des organiseurs en fonction des besoins spécifiques de chaque patient. Ces agendas électroniques permettent de rappeler au patient ses AVQ, et d’augmenter la communication avec l’aidant. Cette étude de convivialité vérifie que l’organiseur pressenti est fonctionnel. Malgré les problèmes techniques rencontrés, tous les participants ont été séduits par l’utilisation des organiseurs. Les aidants ont été convaincus que ces outils amélioreraient la qualité de vie des patients et constitueraient un complément de travail précieux. Les agendas seront améliorés d’après les commentaires des participants et testés dans une étude ultérieure.Mnesic and executive troubles elicited by schizophrenia decrease patient’s capacity to organise their Daily Living Activities (DLA). According to the needs of each patient, PDA (Personal Digital Assistant) were programmed in order to improve their autonomy and to reduce the load of their carers and relatives. These electronic diaries recall patient’s DLA and increase communication with carer. This conviviality study aims at verify that the material is operational. Despite some technical problems, all participants reported a great interest for the use of these diaries. Carers were convinced that these tools would represent an invaluable complement of work, and would improve the quality of life of their patients by bringing them more autonomy. According to the participants reports, PDA will be enhanced and tested in a subsequent study.La esquizofrenia está asociada a los trastornos del funcionamiento mnésico y de ejecución que alteran la capacidad de los pacientes para organizar sus Actividades de la Vida Cotidiana (AVQ). A fin de mejorar su autonomía y de aligerar la carga de sus ayudantes, proponemos programar los organizadores en función de las necesidades específicas de cada paciente. Estas agendas electrónicas permiten al paciente recordar sus AVQ y aumentar la comunicación con el ayudante. Este estudio de la facilidad de uso verifica que el organizador potencial sea funcional. A pesar de los problemas técnicos encontrados, todos los participantes fueron seducidos por el uso de los organizadores. Los ayudantes se convencieron de que estas herramientas mejoran la calidad de vida de los pacientes y constituirían un complemento de trabajo precioso. Las agendas serán mejoradas conforme a los comentarios de los participantes y se probarán en un estudio posterior.A esquizofrenia é associada a transtornos do funcionamento mnésico e executivo que alteram a capacidade dos pacientes em organizar suas Atividades da Vida Cotidiana (Activités de la Vie Quotidienne – AVQ). A fim de melhorar sua autonomia e tornar mais leve a carga de seus auxiliares, propomos programar agendas eletrônicas em função das necessidades específicas de cada paciente. Estes aparelhos permitem lembrar ao paciente suas AVQ, e aumentar a comunicação com o auxiliar. Este estudo de convivialidade verifica se a agenda pressentida é funcional. Apesar dos problemas técnicos que ocorreram, todos os participantes ficaram seduzidos pela utilização das agendas eletrônicas. Os auxiliares ficaram convencidos de que estas ferramentas melhoraram a qualidade de vida dos pacientes e constituiriam um complemento de trabalho precioso. As agendas serão modificadas, segundo os comentários dos participantes, e testadas em um estudo futuro

Prevalence of symptoms of vaginal fi stula in 19 sub-Saharan Africa countries: a meta-analysis of national household survey data

Background Vaginal fi stula is a serious medical disorder characterised by an abnormal opening between the vagina and the bladder or rectum, which results in continuous leakage of urine or stool. The burden of this disorder in sub- Saharan Africa is uncertain. We estimated the lifetime and point prevalence of symptoms of vaginal fi stula in this region using national household surveys based on self-report of symptoms. Methods We considered all Demographic and Health Surveys (DHS) and Multiple Indicators Cluster Surveys (MICS) from sub-Saharan Africa and included data for women of reproductive age (15–49 years). We estimated lifetime prevalence and point prevalence of vaginal fi stula with use of Bayesian hierarchical meta-analysis. Findings We included 19 surveys in our analysis, including 262 100 respondents. Lifetime prevalence was 3·0 cases (95% credible interval 1·3–5·5) per 1000 women of reproductive age. After imputation of missing data, point prevalence was 1·0 case (0·3–2·4) per 1000 women of reproductive age. Ethiopia had the largest number of women who presently have symptoms of vaginal fi stula. Interpretation This study is the fi rst to estimate the burden of vaginal fi stula in 19 sub-Saharan Africa countries using nationally representative survey data. Point prevalence was slightly lower than previously estimated but these earlier estimates are within the prevalence’s credible intervals. Although vaginal fi stula is relatively rare, it is still too common in sub-Saharan Africa

Fistula in sub-Saharan Africa – Authors' reply

info:eu-repo/semantics/publishe

A circumpolar study unveils a positive non-linear effect oftemperature on arctic arthropod availability that may reduce therisk of warming-induced trophic mismatch for breeding shorebirds

Seasonally abundant arthropods are a crucial food source for many migratorybirds that breed in the Arctic. In cold environments, the growth and emergence ofarthropods are particularly tied to temperature. Thus, the phenology of arthropodsis anticipated to undergo a rapid change in response to a warming climate, potentiallyleading to a trophic mismatch between migratory insectivorous birds and their prey.Using data from 19 sites spanning a wide temperature gradient from the Subarcticto the High Arctic, we investigated the effects of temperature on the phenology andbiomass of arthropods available to shorebirds during their short breeding seasonat high latitudes. We hypothesized that prolonged exposure to warmer summertemperatures would generate earlier peaks in arthropod biomass, as well as higherpeak and seasonal biomass. Across the temperature gradient encompassed by ourstudy sites (>10°C in average summer temperatures), we found a 3-day shift inaverage peak date for every increment of 80 cumulative thawing degree-days.Interestingly, we found a linear relationship between temperature and arthropodbiomass only below temperature thresholds. Higher temperatures were associatedwith higher peak and seasonal biomass below 106 and 177 cumulative thawingdegree-days, respectively, between June 5 and July 15. Beyond these thresholds,no relationship was observed between temperature and arthropod biomass. Ourresults suggest that prolonged exposure to elevated temperatures can positivelyinfluence prey availability for some arctic birds. This positive effect could, in part,stem from changes in arthropod assemblages and may reduce the risk of trophicmismatch. Sarctic arthropods, arctic breeding shorebirds, climate warming, insectivorous birds,invertebrate biomass, phenology, trophic mismatcpublishedVersio

A population-based cross-sectional study of age-specific risk factors for high risk human papillomavirus prevalence in rural Nigeria

<p>Abstract</p> <p>Background</p> <p>Cervical cancer, caused by persistent infection with carcinogenic human papillomavirus (HR-HPV), is particularly prevalent in Sub-Saharan Africa and is associated with a high mortality rate. Some studies in West Africa, including our own, have found unusually high HR-HPV across all ages with a slight peak in older women. This increased prevalence at older ages may complicate screen-and-treat programs, which are implemented in regions where HPV prevalence declines with age and typically target women between 30-49 years. A better understanding of the determinants of high HR-HPV prevalence at older ages is needed. The goal of this study is to explore risk factors for HR-HPV prevalence by age among women in our population-based study in Irun, a rural town in southwestern Nigeria.</p> <p>Methods</p> <p>1,420 women were administered a clinic-based questionnaire regarding sexual and reproductive behavior, marital status (including co-wives), and malaria exposure. Logistic regression compared questionnaire responses and PCR positivity for a set of 13 carcinogenic HR-HPV types. Results were stratified by age (15-29, 30-45, 46-55, and 56+ years).</p> <p>Results</p> <p>Birth control use and age at first pregnancy were associated with HR-HPV (<it>p-value </it>= 0.03 and 0.05, respectively). Early age at sexual debut and multiple sex partners were risks for HR-HPV, but did not reach significance (<it>p-value </it>= 0.1 and 0.07, respectively). Neither self-reported malaria nor presence of co-wives in the household was associated with HR-HPV (<it>p-value </it>= 0.85 and 0.24, respectively). In age sub-categories, early age at sexual debut was a significant risk factor for HR-HPV among women 35-45 years (<it>p-value = 0.02</it>). Early age at first pregnancy remained a significant risk factor for women aged 56+ years (<it>p-value </it>= 0.04). Greater than 2 sex partners and use of birth control were associated (though not significantly) with HR-HPV in women aged 30-45 (<it>p-value </it>= 0.08, respectively).</p> <p>Conclusions</p> <p>In this high-risk region with elevated HR-HPV prevalence at older ages, we confirmed previously described, behavioral determinants of HR-HPV. There was no association with self-reported malaria or co-wives, which we had hypothesized might correlate with HR-HPV at older ages.</p