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901.
Communal predators may often need to make especially intricate foraging decisions, as a predator's success may depend on the actions of its neighbours. Here,we consider the decisions made by Portia africana, a jumping spider (Salticidae) that preys on other spiders, including Oecobius amboseli (Oecobiidae), a small prey spider that lives under small sheets of silk (nests) on the walls of buildings. P. africana juveniles settle near oecobiid nests and then ambush oecobiids as they leave or enter the nest. Two or more P. africana juveniles sometimes settle at the same nest and, when an oecobiid is captured, the P. africana juveniles may share the meal. We investigated the joining decisions made by na?ve P. africana juveniles. Experiments were based on using lures (dead spiders positioned in lifelike posture) arranged in a series of 17 different scenes defined by the presence/absence of a nest, the lure types present and the configuration of the lures and the nest. Our findings imply that P. africana juveniles make remarkably precise predatory decisions, with the variables that matter including whether a nest is present, the identity of spiders inside and outside a nest and how spiders are positioned relative to each other and the nest. 相似文献
902.
Robert J. Schinke Justin Bonhomme Kerry R. McGannon Jessica Cummings 《Psychology of sport and exercise》2012,13(6):830-839
ObjectivesThe Super Six World Boxing Classic was conceived by Showtime Sports to feature the best six professional boxers in the super middleweight division (168 pounds) throughout a modified round robin tournament. The objective was to explore the adaptation and mal-adaptation processes of the tournament's original six tournament participants over time.DesignMedia data in the form of documentary episodes (n = 12 episodes, ~30 min each from the foregoing source were transcribed verbatim. Data included athletes' responses prior to their first bout and as each progressed or was eliminated. Boxers' post-bout explanations were also included.MethodThe original six contestants (mean age = 28.8 years at tournament start) from the tournament, with a record of 157 wins and 4 losses, were included within the project. Data were analyzed via thematic analysis (see Braun & Clarke, 2006).ResultsThe following themes were identified: (a) pre-conditions: moving into the tournament (subthemes: positive anticipation, uncertainty), (b) outcomes: moving through the tournament (subthemes: tournament progression, tournament regressions), and (c) consequences: moving out of the tournament (sub-themes: responses of the defeated, the king's adaptation).ConclusionsThis study highlights the adaptation processes of the six tournament contestants, demonstrating how one athlete adapted successfully and became champion through personal focus. The remaining athletes lost at least once, with pre-bout adaptation processes suggesting performance regression. These findings add to the adaptation literature, further contextualizing how adaptation meanings change and unfold over time. 相似文献
903.
904.
A new method is proposed for controlling mosquito-borne diseases. In particular, instead of trying to kill mosquitoes, we suggest provisioning them with food from artificial feeders. Because mosquito populations are frequently limited by ecological factors other than blood meals, such as the availability of egg-laying sites, feeding mosquitoes would not necessarily increase the total number of mosquitoes, but could reduce the number of human-drawn mosquito meals. Like mosquito traps, feeders could divert biting mosquitoes away from people by means of lures, but, after diversion, prevent subsequent human bites by satiating the mosquitoes instead of killing them. Mosquito feeders might reduce the problem of the evolution of resistance to control: in an ecology with mosquito feeders, which provide safe and abundant calories for adult female mosquitoes, there could be selection for preferring (rather than avoiding) feeders, which could eventually lead to a population of feeder-preferring mosquitoes. Artificial feeders also offer the chance to introduce novel elements into the mosquito diet, such as anti- malarial or other anti-parasitic agents. Feeders might directly reduce human bites and harnesses the power of natural selection by selectively favoring feeder-preferring (rather than trap-resistant) mosquitoes. 相似文献
905.
Humans (Homo sapiens) and chimpanzees (Pan troglodytes) can extract socially-relevant information from the static, non-expressive faces of conspecifics. In humans, the face is a valid signal of both personality and health. Recent evidence shows that, like humans, chimpanzee faces also contain personality information, and that humans can accurately judge aspects of chimpanzee personality relating to extraversion from the face alone (Kramer, King, and Ward, 2011). These findings suggest the hypothesis that humans and chimpanzees share a system of personality and facial morphology for signaling socially-relevant traits from the face. We sought to test this hypothesis using a new group of chimpanzees. In two studies, we found that chimpanzee faces contained health information, as well as information of characteristics relating to extraversion, emotional stability, and agreeableness, using average judgments from pairs of individual photographs. In a third study, information relating to extraversion and health was also present in composite images of individual chimpanzees. We therefore replicate and extend previous findings using a new group of chimpanzees and demonstrate two methods for minimizing the variability associated with individual photographs. Our findings support the hypothesis that chimpanzees and humans share a personality signaling system. 相似文献
906.
The effects of two kinds of meditation (open presence and focused) on the facial and physiological aspects of the defensive response to an aversive startle stimulus were studied in a Buddhist monk with approximately 40 years of meditation experience. The participant was exposed to a 115-db, 100-ms acoustic startle stimulus under the 2 meditation conditions, a distraction condition (to control for cognitive and attentional load) and an unanticipated condition (startle presented without warning or instruction). A completely counterbalanced 24-trial, single-subject design was used, with each condition repeated 6 times. Most aspects of the participant's responses in the unanticipated condition did not differ from those of a comparison group of 12 age-matched male controls. Both kinds of meditation produced physiological and facial responses to the startle that were smaller than in the distraction condition. Within meditation conditions, open presence meditation produced smaller physiological and facial responses than focused meditation. These results from a single highly expert meditator indicate that these 2 kinds of meditation can differentially alter the magnitude of a primitive defensive response. 相似文献
907.
Drebing CE Mueller L Van Ormer EA Duffy P LePage J Rosenheck R Drake R Rose GS King K Penk W 《Psychological services》2012,9(1):49-63
The current study provides naturalistic data documenting the pathways-to-care to vocational services for 155 veterans who were receiving some form of mental health care from the Veterans Health Administration and had a vocational need but were not currently enrolled in vocational services. Of the participants, 94.2% had recognized their vocational need, 80.6% reported that they or someone else had sought help to alleviate the need, and 77.4% had previously received some form of vocational services. The median length of the participants' vocational need was more than 4.2 years. Delays associated with recognition, help-seeking, and treatment entry all contributed to the overall delay in entering appropriate care. Filtering factors associated with quicker recognition, seeking help, and receiving services included diagnosis, level of disability, type of vocational need, and support from primary providers, family, and friends. The results provide information for designing interventions to improve service entry by adults with mental health problems and vocational needs. 相似文献
908.
Research on spatial cognition has focused on how animals encode the horizontal component of space. However, most animals travel vertically within their environments, particularly those that fly or swim. Pelagic fish move with six degrees of freedom and must integrate these components to navigate accurately--how do they do this? Using an assay based on associative learning of the vertical and horizontal components of space within a rotating Y-maze, we found that fish (Astyanax fasciatus) learned and remembered information from both horizontal and vertical axes when they were presented either separately or as an integrated three-dimensional unit. When information from the two components conflicted, the fish used the previously learned vertical information in preference to the horizontal. This not only demonstrates that the horizontal and vertical components are stored separately in the fishes' representation of space (simplifying the problem of 3D navigation), but also suggests that the vertical axis contains particularly salient spatial cues--presumably including hydrostatic pressure. To explore this latter possibility, we developed a physical theoretical model that shows how fish could determine their absolute depth using pressure. We next considered full volumetric spatial cognition. Astyanax were trained to swim towards a reward in a Y-maze that could be rotated, before the arms were removed during probe trials. The subjects were tracked in three dimensions as they swam freely through the surrounding cubic tank. The results revealed that fish are able to accurately encode metric information in a volume, and that the error accrued in the horizontal and vertical axes whilst swimming in probe trials was similar. Together, these experiments demonstrate that unlike in surface-bound rats, the vertical component of the representation of space is vitally important to fishes. We hypothesise that the representation of space in the brain of vertebrates could ultimately be shaped by the number of the degrees of freedom of movement that binds the navigating animal. 相似文献
909.
Wallerstein RS 《The International journal of psycho-analysis》2012,93(2):377-399
Although Freud had aspirations of a university structure for psychoanalytic education the sociopolitical structure of the Austro-Hungarian empire precluded this, and psychoanalysis developed by default in the central European heartland within a part-time, private-practice educational structure. With its rapid spread in the post-World-War-II United States, and its ready penetration of American academic psychiatry, a counter educational structure arose in some quarters: the department-of-psychiatry-affiliated institute within the medical school. This article outlines beyond these other, more ambitious, academic vistas (the David Shakow model, the Anna Freud model, the Menninger Foundation, Emory University (USA), AP de BA (Argentina)); conceptions even closer to the ideal (idealized) goal of full-time placement within the university, with strong links to medicine, to the behavioral sciences and to the humanities. The putative advantages of such a structure are presented. 相似文献
910.
Eaton NR Keyes KM Krueger RF Balsis S Skodol AE Markon KE Grant BF Hasin DS 《Journal of abnormal psychology》2012,121(1):282-288
Epidemiological studies of categorical mental disorders consistently report that gender differences exist in many disorder prevalence rates and that disorders are often comorbid. Can a dimensional multivariate liability model be developed to clarify how gender impacts diverse, comorbid mental disorders? We pursued this possibility in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC; N = 43,093). Gender differences in prevalence were systematic such that women showed higher rates of mood and anxiety disorders, and men showed higher rates of antisocial personality and substance use disorders. We next investigated patterns of disorder comorbidity and found that a dimensional internalizing-externalizing liability model fit the data well, where internalizing is characterized by mood and anxiety disorders, and externalizing is characterized by antisocial personality and substance use disorders. This model was gender invariant, indicating that observed gender differences in prevalence rates originate from women and men's different average standings on latent internalizing and externalizing liability dimensions. As hypothesized, women showed a higher mean level of internalizing, while men showed a higher mean level of externalizing. We discuss implications of these findings for understanding gender differences in psychopathology and for classification and intervention. 相似文献