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1.
Ecol Evol ; 13(3): e9873, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36937055

RESUMO

Wolves (Canis lupus) can exert top-down pressure and shape ecological communities through the predation of ungulates and beavers (Castor spp.). Therefore, understanding wolf foraging is critical to estimating their ecosystem-level effects. Specifically, if wolves are consumers that optimize tradeoffs between the cost and benefits of prey acquisition, changes in these factors may lead to prey-switching or negative-density dependent selection with potential consequences for community stability. For wolves, factors affecting cost and benefits include prey vulnerability, risk, reward, and availability, which can vary temporally. We described the wolf diet by the frequency of occurrence and percent biomass and characterized the diet using prey remains found in wolf scats on Isle Royale National Park, Michigan, USA, during May-October 2019 and 2020. We used logistic regression to estimate prey consumption over time. We predicted prey with temporal variation in cost (availability and/or vulnerability) such as adult moose (Alces alces), calf moose, and beaver (Castor canadensis) to vary in wolf diets. We analyzed 206 scats and identified 62% of remains as beaver, 26% as moose, and 12% as other species (birds, smaller mammals, and wolves). Adult moose were more likely to occur in wolf scats in May when moose are in poor condition following winter. The occurrence of moose calves peaked during June-mid-July following birth but before calf vulnerability declined as they matured. By contrast, beaver occurrence in wolf scat did not change over time, reflecting the importance of low-handling cost prey items for recently introduced lone or paired wolves. Our results demonstrate that the wolf diet is responsive to temporal changes in prey costs. Temporal fluctuation in diet may influence wolves' ecological role if prey respond to increased predation risk by altering foraging or breeding behavior.

2.
Mar Pollut Bull ; 174: 113167, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34847416

RESUMO

Marine litter is recognised as imposing a range of costs on marine economies and environments as we target UN Sustainable Development Goals (SDGs) to 2030. Prevention of these avoidable damage costs can restore economic benefits and ocean health. In the Asia-Pacific we estimate the annual damage cost from marine litter to the marine economy has risen eightfold since 2008 and in 2015 was US$10.8 billion (bn), translating to $18.3bn globally ($21.3bn in 2020). In 2020 the present value of global economic damage costs to 2030 and 2050 are $-197bn and $-434bn respectively and as high as $-229bn and $-731bn, if predicted increased plastic production eventuates. As avoidable costs, these projections are the unacceptable "cost of global inaction" in today's terms. Litter prevention by government, industries and the community is needed now, to reduce these predicted marine economic cost impacts to 2050 with environmental benefits.


Assuntos
Plásticos , Desenvolvimento Sustentável , Ásia , Resíduos/análise
3.
Evolution ; 74(5): 1002-1009, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32187385

RESUMO

Pleiotropy between male signals and female preferences can facilitate evolution of sexual communication by maintaining coordination between the sexes. Alternatively, it can favor variation in the mating system, such as a reproductive polymorphism. It is unknown how common either of these scenarios is in nature. In Pacific field crickets (Teleogryllus oceanicus) on Kauai, Hawaii, a mutation (flatwing) that segregates as a single locus is responsible for the rapid loss of song production in males. We used outbred cricket colonies fixed for male wing morph to investigate whether homozygous flatwing and normal-wing (wild-type) females differ in responsiveness to male calling song and propensity to mate when paired with either a flatwing or normal-wing male in the presence or absence of courtship song. Flatwing females were less likely to mount a male than normal-wing females. Females of both genotypes showed a preference for normal-wing males and were more likely to mate in the presence of courtship song; normal-wing females were particularly likely to mate with song. Our results show that negative pleiotropy between obligate male silence and female mating behavior can constrain the evolution of sexual signal loss and contribute to the maintenance of a male reproductive polymorphism in the wild.


Assuntos
Comunicação Animal , Pleiotropia Genética , Gryllidae/fisiologia , Comportamento Sexual Animal , Animais , Feminino , Gryllidae/genética , Masculino
4.
Front Psychol ; 7: 1316, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27625627

RESUMO

Emotional intelligence (EI) was once touted as the panacea for a satisfying and successful life. Consequently, there has been much emphasis on developing interventions to promote this personal resource in applied settings. Despite this, a growing body of research has begun to identify particular contexts when EI does not appear helpful and may even be deleterious to a person, or those they have contact with, suggesting a "dark" side to the construct. This paper provides a review of emergent literature to examine when, why and how trait and ability EI may contribute to negative intrapersonal (psychological ill-health; stress reactivity) and interpersonal outcomes (emotional manipulation; antisocial behavior). Negative effects were found to operate across multiple contexts (health, academic, occupational) however these were often indirect, suggesting that outcomes depend on pre-existing qualities of the person. Literature also points to the possibility of "optimal" levels of EI-both within and across EI constructs. Uneven profiles of self-perceptions (trait facets) or actual emotional skills contribute to poorer outcomes, particularly emotional awareness, and management. Moreover, individuals who possess high levels of skill but have lower self-perceptions of their abilities fare worse that those with more balanced profiles. Future research must now improve methodological and statistical practices to better capture EI in context and the negative corollary associated with high levels.

5.
Acta Orthop ; 81(6): 684-95, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21067432

RESUMO

BACKGROUND AND PURPOSE: Hip resurfacing (HRS) procedures have gained increasing popularity for younger, higher-demand patients with degenerative hip pathologies. However, with concerns regarding revision rates and possible adverse metal hypersensitivity reactions with metal-on-metal articulations, some authors have questioned the hypothesized superiority of hip resurfacing over total hip arthroplasty (THA). In this meta-analysis, we compared the clinical and radiological outcomes and complication rates of these 2 procedures. METHODS: A systematic review was undertaken of all published (Medline, CINAHL, AMED, EMBASE) and unpublished or gray literature research databases up to January 2010. Clinical and radiological outcomes as well as complications of HRS were compared to those of THA using risk ratio, mean difference, and standardized mean difference statistics. Studies were critically appraised using the CASP appraisal tool. RESULTS: 46 studies were identified from 1,124 citations. These included 3,799 HRSs and 3,282 THAs. On meta-analysis, functional outcomes for subjects following HRS were better than or the same as for subjects with a THA, but there were statistically significantly greater incidences of heterotopic ossification, aseptic loosening, and revision surgery with HRS compared to THA. The evidence base showed a number of methodological inadequacies such as the limited use of power calculations and poor or absent blinding of both patients and assessors, possibly giving rise to assessor bias. INTERPRETATION: On the basis of the current evidence base, HRS may have better functional outcomes than THA, but the increased risks of heterotopic ossification, aseptic loosening, and revision surgery following HRS indicate that THA is superior in terms of implant survival.


Assuntos
Artroplastia de Quadril/métodos , Articulação do Quadril/cirurgia , Adulto , Idoso , Artroplastia de Quadril/efeitos adversos , Estudos de Coortes , Feminino , Prótese de Quadril/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Falha de Prótese , Recuperação de Função Fisiológica , Reoperação , Resultado do Tratamento
6.
Knee Surg Sports Traumatol Arthrosc ; 18(3): 325-40, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19851756

RESUMO

Controversy exists regarding the clinical and radiological differences in outcomes between fixed- and mobile-bearing total knee replacements (TKR). The aim of this study was to compare these two TKR designs using a meta-analysis of the electronic databases MEDLINE, EMBASE, CINAHL and AMED in addition to a review of unpublished material. All included papers were critically appraised using a modified PEDro critical appraisal tool. Thirty-three studies were eligible, assessing the outcomes of 3532 TKRs. Analysis suggested that there was no significant difference in clinical or radiological outcomes and complication rates between fixed- and mobile-bearing TKRs.


Assuntos
Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/instrumentação , Análise de Falha de Equipamento , Articulação do Joelho/diagnóstico por imagem , Desenho de Prótese , Feminino , Humanos , Masculino , Radiografia , Amplitude de Movimento Articular , Reoperação , Suporte de Carga
7.
Anim Cogn ; 10(4): 449-59, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17437139

RESUMO

In complex navigation using landmarks, an animal must discriminate between potential cues and show context (condition) sensitivity. Such conditional discrimination is considered a form of complex learning and has been associated primarily with vertebrates. We tested the hypothesis that octopuses and cuttlefish are capable of conditional discrimination. Subjects were trained in two maze configurations (the conditions) in which they were required to select one of two particular escape routes within each maze (the discrimination). Conditional discrimination could be demonstrated by selecting the correct escape route in each maze. Six of ten mud-flat octopuses (Octopus bimaculoides), 6 of 13 pharaoh cuttlefish (Sepia pharaonis), and one of four common cuttlefish (S. officinalis) demonstrated conditional discrimination by successfully solving both mazes. These experiments demonstrate that cephalopods are capable of conditional discrimination and extend the limits of invertebrate complex learning.


Assuntos
Cefalópodes , Aprendizagem por Discriminação , Aprendizagem em Labirinto , Comportamento Espacial , Animais , Condicionamento Clássico , Percepção Espacial
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