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JODI HALPERN 《Bioethics》2012,26(2):108-116
There is an important gap in philosophical, clinical and bioethical conceptions of decision‐making capacity. These fields recognize that when traumatic life circumstances occur, people not only feel afraid and demoralized, but may develop catastrophic thinking and other beliefs that can lead to poor judgment. Yet there has been no articulation of the ways in which such beliefs may actually derail decision‐making capacity. In particular, certain emotionally grounded beliefs are systematically unresponsive to evidence, and this can block the ability to deliberate about alternatives. People who meet medico‐legal criteria for decision‐making capacity can react to health and personal crises with such capacity‐derailing reactions. One aspect of this is that a person who is otherwise cognitively intact may be unable to appreciate her own future quality of life while in this complex state of mind. This raises troubling ethical challenges. We cannot rely on the current standard assessment of cognition to determine decisional rights in medical and other settings. We need to understand better how emotionally grounded beliefs interfere with decision‐making capacity, in order to identify when caregivers have an obligation to intervene.  相似文献   
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Abstract

This article examines the practice of the international judicial and arbitral tribunals thus far in delimiting the continental shelf beyond 200?nm, and indicates the trend reflected in the decisions. However, the article disagrees with the critical observation of the tribunals that the delimitation method for the continental shelf beyond 200?nm should follow that within 200?nm. The delimitation of the continental shelf beyond 200?nm is essentially different from the single maritime delimitation within 200?nm, and various methods may be employed in order to achieve an equitable result in a particular case.  相似文献   
114.
Conventional medical ethics and the law draw a bright line distinguishing the permitted practice of withdrawing life‐sustaining treatment from the forbidden practice of active euthanasia by means of a lethal injection. When clinicians justifiably withdraw life‐sustaining treatment, they allow patients to die but do not cause, intend, or have moral responsibility for, the patient's death. In contrast, physicians unjustifiably kill patients whenever they intentionally administer a lethal dose of medication. We argue that the differential moral assessment of these two practices is based on a series of moral fictions – motivated false beliefs that erroneously characterize withdrawing life‐sustaining treatment in order to bring accepted end‐of‐life practices in line with the prevailing moral norm that doctors must never kill patients. When these moral fictions are exposed, it becomes apparent that conventional medical ethics relating to end‐of‐life decisions is radically mistaken.  相似文献   
115.
The use of diets with increased fibre content from alternative feedstuffs less digestible for pigs is a solution considered to limit the impact of increased feed costs on pig production. This study aimed at determining the impact of an alternative diet on genetic parameters for growth, feed efficiency, carcass composition and meat quality traits. A total of 783 Large White pigs were fed a high-fibre (HF) diet and 880 of their sibs were fed a conventional (CO) cereal-based diet. Individual daily feed intake, average daily gain, feed conversion ratio and residual feed intake were recorded as well as lean meat percentage (LMP), carcass yield (CY) and meat quality traits. Pigs fed the CO diet had better performances for growth and feed efficiency than pigs fed the HF diet. They also had lower LMP and higher CY. In addition, pigs fed the CO diet had lower loin percentage and ham percentage and higher backfat percentage. No differences were observed in meat quality traits between diets, except for a* and b* values. For all traits, the genetic variances and heritability were not different between diets. Genetic correlations for traits between diets ranged between 0.80 ± 0.13 and 0.99 ± not estimable, and none were significantly different from 0.99, except for LMP. Thus, traits in both diets were considered as mainly affected by similar sets of genes in the two diets. A genetic correlation lower than 0.80 would justify redesigning the breeding scheme; however, some genetic correlations did not differ significantly from 0.80 either. Therefore, larger populations are needed for a more definitive answer regarding the design of the breeding scheme. To further evaluate selection strategies, a production index was computed within diets for the 29 sires with estimated breeding value reliability higher than 0.35. The rank correlation between indices estimated in the CO and in the HF diet was 0.72. Altogether, we concluded that limited interaction between feed and genetics could be evidenced, and based on these results there is no need to change pig selection schemes to adapt to the future increased use of alternative feedstuffs in production farms.  相似文献   
116.
In patchy environments, patch-leaving decision rules are a keycomponent of the foraging behavior of parasitoids that haveto share their searching time between the different host patchesto optimize the number of ovipositions. It has been experimentallyshown that one of the proximate cues involved in patch-leavingdecision is the number of ovipositions performed by the parasitoidwhile in the patch. Ovipositions can have either a decrementalor an incremental effect on the patch residence time dependingon parasitoid species. Previous theoretical studies have suggestedthat environmental conditions and the ability of parasitoidsto reliably estimate the number of available hosts on a patchwhen entering it should influence how patch departure dependson ovipositions. We developed an individual-based model to testa large variety of patch-leaving decision rules in differentenvironmental conditions. This model includes a more realisticrepresentation of individual acquisition of information thanprevious theoretical work. In accordance with previous results,we show that the best use of information depends on environmentalconditions. Moreover, we identify the environmental factorsthat have a decisive influence on the most appropriate typeof rule (incremental or decremental). Decremental mechanismsare most efficient only in restricted conditions characterizedby a large number of patches and few parasitoids. The sensitivityof decision rules to frequency-dependent processes was testedby numerical invasibility experiments. Rare mutants using anyalternative rule never outperform populations using a high-performancerule. Incremental rules seem to be more sensitive than decrementalones to frequency-dependent processes.  相似文献   
117.
1. Kin recognition is important in many social insects, but has also been found in several nonsocial insects such as parasitoids, where it plays an important role in oviposition behaviour. In nonparasitic arthropods, however, the fitness of ovipositing females also depends on the oviposition behaviour of related and unrelated females, especially when eggs are oviposited in clusters by several females. 2. In this paper, kin recognition in a predatory mite, Iphiseius degenerans, is studied. Mothers are capable of determining offspring sex ratio, and cannibalism on juvenile stages is a common phenomenon. Therefore, kin recognition is expected to occur in this predator. 3. Oviposition behaviour of this species is particularly interesting because it alternates foraging bouts in flowers with deposition of a single egg at a time on a leaf, where predation risk is lower. The eggs are not scattered but are deposited in clusters. After feeding in a flower, females therefore have to locate clusters of eggs. 4. Experiments on two‐choice arenas showed that females prefer to oviposit close to conspecific eggs rather than close to heterospecific eggs. Females also showed a preference for ovipositing near closely related conspecific eggs rather than more distantly related eggs. 5. Females tended to displace eggs of heterospecifics more frequently than eggs of conspecifics. 6. These behavioural observations show that females can discriminate not only between conspecific and heterospecific eggs but also between eggs that vary in degree of relatedness. This enables females to oviposit in clusters containing related eggs and thus avoid cannibalism by non‐kin and/or produce adaptive sex ratios despite the fact that the adults commute between flowers and leaves.  相似文献   
118.
1. The distribution of the large orb‐weaving spider Argiope trifasciata in old field habitats of North America and the habitat selection process this species used was studied for 2 years. 2. Because web spiders have limited dispersal abilities and an energetically costly prey capture device, they do not have the ability to sample potential foraging sites. Structural complexity of the vegetation to which the web must be attached is relatively easy to assess. The hypothesis that the structural complexity is a primary factor in determining initial web site selection was tested both by relating the natural distribution of the spiders across habitats to vegetational complexity and by manipulating the complexity of the habitats in a series of experiments. 3. Argiope trifasciata was not distributed evenly among three old field vegetation types. Habitat complexity was related to spider density in both years although no measure of insect activity, prey capture, or prey consumption was correlated with spider distribution. 4. Three experimental manipulations were conducted to test the impact of habitat structure on spider establishment: (1) the amount of natural vegetation was reduced, (2) structures were added to a simple habitat, and (3) the complexity of the structures added was varied. In each case, spiders were introduced and establishment of webs was monitored. In all manipulations, spider establishment was related to the complexity of the substrate available. 5. These results are important for understanding the cues that influence foraging site selection and therefore provide insight into the distribution of species with limited dispersal abilities and high site investment requirements.  相似文献   
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