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261.
The use of voluntary assisted dying as an end‐of‐life option has stimulated concerns and debates over the past decades. Although public attitudes towards voluntary assisted dying (including euthanasia and physician‐assisted suicide) are well researched, there has been relatively little study of the different reasons, normative reasoning and rhetorical strategies that people invoke in supporting or contesting voluntary assisted dying in everyday life. Using a mix of computational textual mining techniques, keyword study and qualitative thematic coding to analyse public submissions to a parliamentary inquiry into voluntary assisted dying in Australia, this study critically examines the different reasons, normative reasoning and rhetorical strategies that people invoke in supporting or contesting voluntary assisted dying in everyday life. The analysis identified complex and potentially contradictory ethical principles being invoked on both sides of the debate. These findings deepen our understanding of the moral basis of public reasoning about end‐of‐life matters and will help to inform future discussions on policy and law reform. The findings underscore the importance of sound normative reasoning and the use of caution when interpreting opinion polls to inform policy.  相似文献   
262.
Edmund Henden 《Bioethics》2016,30(4):293-298
In an earlier article in this journal I argued that the question of whether heroin addicts can give voluntary consent to take part in research which involves giving them a choice of free heroin does not – in contrast with a common assumption in the bioethics literature – depend exclusively on whether or not they possess the capacity to resist their desire for heroin. In some cases, circumstances and beliefs might undermine the voluntariness of the choices a person makes even if they do possess a capacity for self‐control. Based on what I took to be a plausible definition of voluntariness, I argued that the circumstances and beliefs typical of many vulnerable heroin addicts are such that we have good reasons to suspect they cannot give voluntary consent to take part in such research, even assuming their desire for heroin is not irresistible. In a recent article in this journal, Uusitalo and Broers object to this on the grounds that I misdescribe heroin addicts' options set, that the definition of voluntariness on which I rely is unrealistic and too demanding, and, more generally, that my view of heroin addiction is flawed. I think their arguments derive from a misunderstanding of the view I expressed in my article. In what follows I hope therefore to clarify my position.  相似文献   
263.
Implementation of effective conservation planning relies on a robust understanding of the spatiotemporal distribution of the target species. In the marine realm, this is even more challenging for species rarely seen at the sea surface due to their extreme diving behavior like the sperm whales. Our study aims at (a) investigating the seasonal movements, (b) predicting the potential distribution, and (c) assessing the diel vertical behavior of this species in the Mascarene Archipelago in the south‐west Indian Ocean. Using 21 satellite tracks of sperm whales and eight environmental predictors, 14 supervised machine learning algorithms were tested and compared to predict the whales'' potential distribution during the wet and dry season, separately. Fourteen of the whales remained in close proximity to Mauritius, while a migratory pattern was evidenced with a synchronized departure for eight females that headed towards Rodrigues Island. The best performing algorithm was the random forest, showing a strong affinity of the whales for sea surface height during the wet season and for bottom temperature during the dry season. A more dispersed distribution was predicted during the wet season, whereas a more restricted distribution to Mauritius and Reunion waters was found during the dry season, probably related to the breeding period. A diel pattern was observed in the diving behavior, likely following the vertical migration of squids. The results of our study fill a knowledge gap regarding seasonal movements and habitat affinities of this vulnerable species, for which a regional IUCN assessment is still missing in the Indian Ocean. Our findings also confirm the great potential of machine learning algorithms in conservation planning and provide highly reproductible tools to support dynamic ocean management.  相似文献   
264.
1. Temperature rise due to climate change affects seasonal activity times, leading to a discordance of phenology among species and changing the strength of interaction between species. Understanding how temperature changes will affect the length of a species’ activity period is essential in order to forecast its response to climate warming.2. We investigated the thermal physiology and monthly activity of a skink from subtropical areas in Taiwan, Scincella formosensis. In addition, we predicted its response to climate warming and potential landscape vegetation changes using a mechanistic model, Niche MapperTM. We incorporated the animals’ thermal traits and climatic data to simulate thermally suitable time for activity each month in two sites (open area, dense forest).3. We found that this species restricts its activity to the cool months of the year, and that juveniles emerge in June. The thermally suitable period for activity is predicted to be longer in cool months than warm months.4. Our model predicts that a 3 °C increase in temperature will curtail the thermally suitable time for activity in open areas in late spring and result in very minimal time for activity in the summer, even when dense forest is available. These results add to the growing body of literature indicating that a temperature rise will have a widespread impact on sub/tropical forest reptiles.  相似文献   
265.
We studied the effect of pennate vs. fusiform muscle architecture on the rate of torque development (RTD) by examining the predominately fusiform elbow flexors (EF) and highly-pennate knee extensors (KE). Seventeen male volunteers (28.4 ± 6.2 years) performed explosive isometric EF and KE contractions (MVCs). Biceps brachii and vastus lateralis fascicle angles were measured to confirm their architecture, and both the rate of voluntary muscle activation (root-mean-square EMG in the 50 ms before contraction onset; EMG-50) and electromechanical delay (EMD; depicting muscle-tendon series elasticity) were assessed as control variables to account for their influence on RTD. MVC torque, early (RTD50) and late (RTD200) RTDs were calculated and expressed as absolute and normalized values. Absolute MVC torque (+412%), RTD50 (+215%), and RTD200 (+427%) were significantly (p < 0.001) higher in KE than EF. However, EF RTD50 was faster (+178%) than KE after normalization (p = 0.02). EMG-50 and EMD did not differ between muscle groups. The results suggest that the faster absolute RTD in KE is largely associated with its higher maximal torque capacity, however in the absence of differences in rates of muscle activation, fiber type, and EMD the fusiform architecture of EF may be considered a factor allowing its faster early RTD relative to strength capacity.  相似文献   
266.
The analysis of single motor unit (SMU) activity provides the foundation from which information about the neural strategies underlying the control of muscle force can be identified, due to the one-to-one association between the action potentials generated by an alpha motor neuron and those received by the innervated muscle fibers. Such a powerful assessment has been conventionally performed with invasive electrodes (i.e., intramuscular electromyography (EMG)), however, recent advances in signal processing techniques have enabled the identification of single motor unit (SMU) activity in high-density surface electromyography (HDsEMG) recordings. This matrix, developed by the Consensus for Experimental Design in Electromyography (CEDE) project, provides recommendations for the recording and analysis of SMU activity with both invasive (needle and fine-wire EMG) and non-invasive (HDsEMG) SMU identification methods, summarizing their advantages and disadvantages when used during different testing conditions. Recommendations for the analysis and reporting of discharge rate and peripheral (i.e., muscle fiber conduction velocity) SMU properties are also provided. The results of the Delphi process to reach consensus are contained in an appendix. This matrix is intended to help researchers to collect, report, and interpret SMU data in the context of both research and clinical applications.  相似文献   
267.
Juveniles of many coral reef fish species are thought to either follow the same bathymetric distribution patterns as the adults, or to occupy shallower waters. However, our knowledge base suffers a dearth of data from the deep reefs (>40 m). In a recent survey of the deep reefs of the northern Gulf of Aqaba (<65 m), we examined the bathymetric distribution of 26 diurnal zooplanktivorous species. In sharp contrast to the general trend known from the literature and from this research, the abundance of juvenile zebra angelfish, Genicanthus caudovittatus, peaked at deeper waters (60–65 m) compared with the adults (30 m). This suggests that the deeper reefs may serve as nursery grounds for the zebra angelfish. Peak juvenile abundance coincided with relatively low predator abundances. This raises the question, which factors constrain the bathymetric distribution of the remaining species. Our findings stress the potential importance of deep coral reef research for understanding the ecological patterns and processes that govern reef community structure.  相似文献   
268.
During ship surveys harbor porpoises are only visible when breaking the sea surface to breathe, while during aerial surveys they may be seen down to 2 m below the surface. The fractions of time spent at these two depths can be used for correcting visual surveys to actual population estimates, which are essential information on the status and management of the species. Thirty‐five free‐ranging harbor porpoises (Phocoena phocoena) were tracked in the region between the Baltic and the North Sea for 25–349 d using Argos satellite transmitters. No differences were found in surface behavior between geographical areas or the size of the animals. Slight differences were found between the two sexes and time of day. Surface time peaked in April, where 6% was spent with the transmitter above surface and 61.5% between 0 and 2 m depth, while the minimum values occurred in February (3.4% and 42.5%, respectively). The analyses reveal that individual variation among porpoises is the most important factor in explaining variation in surface rates. However, the large number of animals documented in the present study covering a wide range of age and sex groups justifies the use of the seasonal average surface times for correcting abundance surveys.  相似文献   
269.
Prolonged exposure to cold can impair manual performance, which in turn can affect work task performance. We investigated whether mild whole-body cold stress would affect isometric force control during submaximal hand grip and key pinch tasks. Twelve male participants performed isometric hand grip and key pinch tasks at 10% and 30% of maximal voluntary contraction (MVC) for 30 and 10 s respectively, in cold (8 °C) and control (25 °C) conditions. Finger temperature decreased significantly by 18.7 ± 2.1 °C and continuous low-intensity shivering in the upper trunk increased significantly in intensity and duration during cold exposure. Rectal temperature decreased similarly for the 8 °C and 25 °C exposures. Force variability (FCv) was <2% for the hand grip tasks, and <3% for the key pinch tasks. No significant changes in FCv or force accuracy were found between the ambient temperatures. In conclusion, isometric force control during hand grip and key pinch tasks was maintained when participants experienced mild whole-body cold stress compared with when they were thermally comfortable.  相似文献   
270.
SPERM WHALES TAGGED WITH TRANSPONDERS AND TRACKED UNDERWATER BY SONAR   总被引:4,自引:0,他引:4  
Abstract: Two sperm whales tagged with acoustic transponder tags were tracked by sonar during a cruise from 16 to 30 October 1991 in the southeast Caribbean west of Dominica Island. The whales dove to depths of 400–600 m and more, including a dive to 1,185 m and one possibly to 2,000 m. They were tracked for periods of 3–14 h, over distances of 8.5–40 km. The tagged whales were found together four and eight days after tagging, and were tracked simultaneously for 13 h, over 31 km. Whale movements on different days at the surface averaged from 0.68 to 0.82 m/set, with dive descent rates from 0.82 to 1.13 m/set, ascent rates from 0.74 to 1.16 m/set, and horizontal movement during dives from 0.76 to 1.29 m/set. Dives lasted from 18 min to 1 h and 13 min, averaging 33 and 41 min on different days. Every track ended when tag signals became obscured at night by dense biological scatterers concentrated in offshore areas where the whales were diving. Both tagged whales appear to have been males of 15 and 11m, each dominant in different groups; but when together the larger whale was dominant, as evidenced by chases and agonistic vocalizations. The whales did not appear to react to the tags or to the sounds associated with tracking (30, 32, and 36 kHz).  相似文献   
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