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221.
Polder-Verkiel SE 《Science and engineering ethics》2012,18(1):117-141
In 2008 a young man committed suicide while his webcam was running. 1,500 people apparently watched as the young man lay dying:
when people finally made an effort to call the police, it was too late. This closely resembles the case of Kitty Genovese
in 1964, where 39 neighbours supposedly watched an attacker assault and did not call until it was too late. This paper examines
the role of internet mediation in cases where people may or may not have been good Samaritans and what their responsibilities
were. The method is an intuitive one: intuitions on the various potentially morally relevant differences when it comes to
responsibility between offline and online situations are examined. The number of onlookers, their physical nearness and their
anonymity have no moral relevance when it comes to holding them responsible. Their perceived reality of the situation and
ability to act do have an effect on whether we can hold people responsible, but this doesn’t seem to be unique to internet
mediation. However the way in which those factors are intrinsically connected to internet mediation does seem to have a diminishing
effect on responsibility in online situations. 相似文献
222.
223.
The primary objective of this study was to investigate the utility of the two-component theory of planned behaviour (TPB) in understanding physical activity intentions and behaviour in rural and small town breast cancer survivors. The secondary objective was to elicit the most common behavioural, normative and control beliefs of rural and small town survivors regarding physical activity. Using a cross-sectional survey design, 524 rural and small town breast cancer survivors completed a mailed survey that assessed physical activity and TPB variables. Physical activity intention explained 12% of the variance in physical activity behaviour (p?0.01) while the TPB constructs together explained 43% of the variance in physical activity intention (p?0.01). Unique behavioural, normative and control beliefs were elicited from the sample. The two-component TPB framework appears to be a suitable model to initiate an understanding of physical activity determinants among rural and small town breast cancer survivors. These data can be used in the development and establishment of physical activity behaviour interventions and health promotion materials designed to facilitate physical activity behaviour among rural and small town breast cancer survivors. 相似文献
224.
Papadopoulos N McGinley J Tonge B Bradshaw J Saunders K Murphy A Rinehart N 《Autism》2012,16(6):627-640
The relationship of motor proficiency with emotional/behavioural disturbance, autistic symptoms and communication disturbance was investigated in children diagnosed with autism and Asperger's disorder (AD). The Movement Assessment Battery for Children was used as a measure of motor impairment, and the Developmental Behavioural Checklist was used as a measure of emotional/behavioural disturbance in the following groups: AD (n?=?22), high functioning autism (HFA) (n?=?23), LFA (n?=?8) and typically developing children (n?=?20). The HFA group had more difficulty with motor items, such as ball skills and balance, than did the AD group. There were significant positive correlations between impairments in motor proficiency (in particular ball skills and balance) and emotional/behavioural disturbance, autistic symptoms and communication disturbance. These findings are consistent with the hypothesis that there are qualitative and quantitative differences in the motor profile between autism and AD. In addition, the association between motor proficiency impairment and emotional/behavioural disturbance in autism and AD emphasizes the importance for screening of co-occurring emotional/behavioural symptoms in individuals with motor difficulties. These findings have implications for the potential use of adjunct motor measures in the diagnosis and definition of autism spectrum disorders. 相似文献
225.
Problems with social anxiety are frequently reported in people with autism spectrum disorders (ASD). It is possible that social anxiety, when present, exacerbates the experience of hostility and other forms of aggression in relation to ASD symptoms. This study sought to determine if social anxiety symptoms mediate the relationship between features of ASD and feelings of hostility in young adults. Self-report measures of social anxiety, ASD, and facets of aggression were collected in a non-clinical sample (n = 618) of college students. Social anxiety was found to partially mediate the relationship between ASD features and self-reported hostility. There was also evidence for inconsistent mediation, such that social anxiety dampened the strength of the relationship between ASD symptoms and verbal and physical aggression. Findings highlight the potential influence of associated psychiatric symptoms in people with ASD. In addition, dimensional conceptualization of ASD symptoms, as opposed to a categorical approach solely, may be a useful approach to studying complex personality processes. 相似文献
226.
The Bengalese finch (Lonchura striata var. domestica) is a species of songbird. Males sing courtship songs with complex note-to-note transition rules, while females discriminate
these songs when choosing their mate. The present study uses serial reaction time (RT) to examine the characteristics of the
Bengalese finches’ sequential behaviours beyond song production. The birds were trained to produce the sequence with an “A–B–A”
structure. After the RT to each key position was determined to be stable, we tested the acquisition of the trained sequential
response by presenting novel and random three-term sequences (random test). We also examined whether they could abstract the
embedded rule in the trained sequence and apply it to the novel test sequence (abstract test). Additionally, we examined rule
abstraction through example training by increasing the number of examples in baseline training from 1 to 5. When considered
as (gender) groups, training with 5 examples resulted in no statistically significant differences in the abstract tests, while
statistically significant differences were observed in the random tests, suggesting that the male birds learned the trained
sequences and transferred the abstract structure they had learned during the training trials. Individual data indicated that
males, as opposed to females, were likely to learn the motor pattern of the sequence. The results are consistent with observations
that males learn to produce songs with complex sequential rules, whereas females do not. 相似文献
227.
Non-human primates possess species-specific repertoires of acoustically distinct call types that can be found in adults in
predictable ways. Evidence for vocal flexibility is generally rare and typically restricted to acoustic variants within the
main call types or sequential production of multiple calls. So far, evidence for context-specific call sequences has been
mainly in relation to external disturbances, particularly predation. In this study, we investigated extensively the vocal
behaviour of free-ranging and individually identified Diana monkeys in non-predatory contexts. We found that adult females
produced four vocal structures alone (‘H’, ‘L’, ‘R’ and ‘A’ calls, the latter consisting of two subtypes) or combined in non-random
ways (‘HA’, ‘LA’ and ‘RA’ call combinations) in relation to ongoing behaviour or external events. Specifically, the concatenation
of an introductory call with the most frequently emitted and contextually neutral ‘A’ call seems to function as a contextual
refiner of this potential individual identifier. Our results demonstrate that some non-human primates are able to increase
the effective size of their small vocal repertoire not only by varying the acoustic structure of basic call types but also
by combining them into more complex structures. We have demonstrated this phenomenon for a category of vocalisations with
a purely social function and discuss the implications of these findings for evolutionary theories of primate vocal communication. 相似文献
228.
It has been speculated that cage mesh exerts a shaping influence on reaching behavior by captive apes, which is then misconstrued
as pointing by human observers. Although this notion is clearly falsified by the pointing of captive language-trained apes—who
point in the absence of intervening cage mesh—nevertheless, the degree to which cage mesh might influence pointing hand shapes
by captive great apes in other housing environments remains relatively unexplored. We examined 259 pointing gestures displayed
in archival footage from over 18 h of observation by three nonlanguage-trained chimpanzees housed at a biomedical research
center. We coded points in relation to how close to the boundaries of the diamond-shaped cage mesh their points were displayed.
We found that points with the whole hand were significantly more likely to be displayed away from the mesh boundaries, relative
to points with the index finger or other single-digit points. However, points of each hand shape were displayed at each location,
demonstrating that these physical parameters do not fully account for the number of fingers extended while pointing by chimpanzees. 相似文献
229.
Although rats are able to build complex spatial representations of their surroundings during exploration, the nature of the
encoded information is still a matter for debate. In particular, it is not well established if rats can process the topological
structure of the environment in such a way that they are aware of the connections existing between remote places. Here, rats
were first exposed for four 5-min trials to a complex environment divided into several sectors that were separated by doors
allowing either unrestricted or restricted access to other sectors. In the fifth test trial, we measured the behavior of the
animals while they explored the same environment in which, however, they faced changes that either altered or did not alter
the topological structure of the environment. In experiment 1, closing previously opened doors prevented the rat from having
direct access between corresponding sectors. In experiment 2, opening previously closed doors allowed direct access between
sectors that had not been directly accessible. In each experiment, control doors allowed us to discard the mere influence
of door manipulation. We compared the rats’ exploratory behavior in response to door manipulations that either strongly altered
or did not alter the ability to commute between sectors and found evidence that the animals displayed differential reactions
to the two types of door manipulations. This implies that during exploration rats build a precise map of the connectivity
of space that can be flexibly updated and used for efficient navigation. 相似文献
230.
Uneconomical choices by humans or animals that evaluate reward options challenge the expectation that decision-makers always
maximize the return currency. One possible explanation for such deviations from optimality is that the ability to sense differences
in physical value between available alternatives is constrained by the sensory and cognitive processes for encoding profitability.
In this study, we investigated the capacity of a nectarivorous bat species (Glossophaga commissarisi) to discriminate between sugar solutions with different concentrations. We conducted a two-alternative free-choice experiment
on a population of wild electronically tagged bats foraging at an array of computer-automated artificial flowers that recorded
individual choices. We used a Bayesian approach to fit individual psychometric functions, relating the strength of preferring
the higher concentration option to the intensity of the presented stimulus. Psychometric analysis revealed that discrimination
ability increases non-linearly with respect to intensity. We combined this result with a previous psychometric analysis of
volume perception. Our theoretical analysis of choice for rewards that vary in two quality dimensions revealed regions of
parameter combinations where uneconomic choice is expected. Discrimination ability may be constrained by non-linear perceptual
and cognitive encoding processes that result in uneconomical choice. 相似文献