Summing the strokes: energy economy in northern elephant seals during large-scale foraging migrations.

BackgroundThe energy requirements of free-ranging marine mammals are challenging to measure due to cryptic and far-ranging feeding habits, but are important to quantify given the potential impacts of high-level predators on ecosystems. Given their large body size and carnivorous lifestyle, we would predict that northern elephant seals (Mirounga angustirostris) have elevated field metabolic rates (FMRs) that require high prey intake rates, especially during pregnancy. Disturbance associated with climate change or human activity is predicted to further elevate energy requirements due to an increase in locomotor costs required to accommodate a reduction in prey or time available to forage. In this study, we determined the FMRs, total energy requirements, and energy budgets of adult, female northern elephant seals. We also examined the impact of increased locomotor costs on foraging success in this species.ResultsBody size, time spent at sea and reproductive status strongly influenced FMR. During the short foraging migration, FMR averaged 90.1 (SE = 1.7) kJ kg(-1)d(-1) - only 36 % greater than predicted basal metabolic rate. During the long migration, when seals were pregnant, FMRs averaged 69.4 (±3.0) kJ kg(-1)d(-1) - values approaching those predicted to be necessary to support basal metabolism in mammals of this size. Low FMRs in pregnant seals were driven by hypometabolism coupled with a positive feedback loop between improving body condition and reduced flipper stroking frequency. In contrast, three additional seals carrying large, non-streamlined instrumentation saw a four-fold increase in energy partitioned toward locomotion, resulting in elevated FMRs and only half the mass gain of normally-swimming study animals.ConclusionsThese results highlight the importance of keeping locomotion costs low for successful foraging in this species. In preparation for lactation and two fasting periods with high demands on energy reserves, migrating elephant seals utilize an economical foraging strategy whereby energy savings from reduced locomotion costs are shuttled towards somatic growth and fetal gestation. Remarkably, the energy requirements of this species, particularly during pregnancy, are 70-80 % lower than expected for mammalian carnivores, approaching or even falling below values predicted to be necessary to support basal metabolism in mammals of this size

O uso dos applets para o ensino de fisica

Orientador : Lucas Ferrari de OliveiraArtigo (especialização) - Universidade Federal do Paraná, Setor de Educação Profissional e Tecnológica, Curso de Especialização em Mídias Integradas na Educação.Inclui referência

Remote sensing in ecology and conservation: three years on

Editorial

Remote sensing in ecology and conservation: three years on

In 2014, Wiley and the Zoological Society of London launched Remote Sensing in Ecology and Conservation, an open‐access journal that aims to support communication and collaboration among experts in remote sensing, ecology and conservation science. Remote sensing was from the start understood as the acquisition of information about an object or phenomenon through a device that is not in physical contact with the object, thus including camera traps, field spectrometry, terrestrial and aquatic acoustic sensors, aerial and satellite monitoring as well as ship‐borne automatic identification systems (Pettorelli et al. 2015). The primary goals of this new journal were, and still are, to maximize the understanding and uptake of remote sensing‐based techniques and products by the ecological and conservation communities, prioritizing findings that advance the scientific basis of, and applied outcomes from, ecology and conservation science; and to identify ecological challenges that might direct development of future remote sensors and data products

Use of warfarin in long-term care: a systematic review

<p>Abstract</p> <p>Background</p> <p>The use of warfarin in older patients requires special consideration because of concerns with comorbidities, interacting medications, and the risk of bleeding. Several studies have suggested that warfarin may be underused or inconsistently prescribed in long-term care (LTC); no published systematic review has evaluated warfarin use for stroke prevention in this setting. This review was conducted to summarize the body of published original research regarding the use of warfarin in the LTC population.</p> <p>Methods</p> <p>A systematic literature search of the PubMed, Cumulative Index to Nursing and Allied Health Literature, and Cochrane Library was conducted from January 1985 to August 2010 to identify studies that reported warfarin use in LTC. Studies were grouped by (1) rates of warfarin use and prescribing patterns, (2) association of resident and institutional characteristics with warfarin prescribing, (3) prescriber attitudes and concerns about warfarin use, (4) warfarin management and monitoring, and (5) warfarin-related adverse events. Summaries of study findings and quality assessments of each study were developed.</p> <p>Results</p> <p>Twenty-two studies met the inclusion criteria for this review. Atrial fibrillation (AF) was the most common indication for warfarin use in LTC and use of warfarin for stroke survivors was common. Rates of warfarin use in AF were low in 5 studies, ranging from 17% to 57%. These usage rates were low even among residents with high stroke risk and low bleeding risk. Scored bleeding risk had no apparent association with warfarin use in AF. In physician surveys, factors associated with not prescribing warfarin included risk of falls, dementia, short life expectancy, and history of bleeding. International normalized ratio was in the target range approximately half of the time. The combined overall rate of warfarin-related adverse events and potential events was 25.5 per 100 resident months on warfarin therapy.</p> <p>Conclusions</p> <p>Among residents with AF, use of warfarin and maintenance of INR levels to prevent stroke appear to be suboptimal. Among prescribers, perceived challenges associated with warfarin therapy often outweigh its benefits. Further research is needed to explicitly consider the appropriate balancing of risks and benefits in this frail patient population.</p

Do female offenders differ? Comparing the criminal histories of serious violent perpetrators with a control sample

In view of earlier research, female offenders have not received as much attention as male perpetrators. Thus, the research aimed to gain insight into the types of offences committed by serious violent female offenders (n = 206; those who had committed grievous bodily harm, attempted murder, or homicide) and to explore differences with control female perpetrators (n = 447); control offenders were matched according to age and year of offence of the serious violent offenders. The purpose was to, therefore, gather an understanding of female offenders and to determine if the serious violent perpetrators differed from the control sample. A UK police force provided data of offences committed between April 2001 and April 2011. Descriptive information was analysed, with comparisons being made using Mann–Whitney U tests and chi-square analyses. About 72.3% (n = 149) of serious violent offenders had one or more recorded convictions and were significantly more likely to have committed a previous violent offence than the control sample. On the other hand, control perpetrators had a higher likelihood of having previously committed a theft-related offence, when compared to serious violent females. Therefore, the findings indicate the types of offences committed by female offenders and highlight the differences between serious violent perpetrators and offenders in the control sample. The implications and limitations are discussed