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1.
Sci Rep ; 10(1): 19474, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33173126

RESUMO

Using satellite imagery, drone imagery, and ground counts, we have assembled the first comprehensive global population assessment of Chinstrap penguins (Pygoscelis antarctica) at 3.42 (95th-percentile CI: [2.98, 4.00]) million breeding pairs across 375 extant colonies. Twenty-three previously known Chinstrap penguin colonies are found to be absent or extirpated. We identify five new colonies, and 21 additional colonies previously unreported and likely missed by previous surveys. Limited or imprecise historical data prohibit our assessment of population change at 35% of all Chinstrap penguin colonies. Of colonies for which a comparison can be made to historical counts in the 1980s, 45% have probably or certainly declined and 18% have probably or certainly increased. Several large colonies in the South Sandwich Islands, where conditions apparently remain favorable for Chinstrap penguins, cannot be assessed against a historical benchmark. Our population assessment provides a detailed baseline for quantifying future changes in Chinstrap penguin abundance, sheds new light on the environmental drivers of Chinstrap penguin population dynamics in Antarctica, and contributes to ongoing monitoring and conservation efforts at a time of climate change and concerns over declining krill abundance in the Southern Ocean.


Assuntos
Conservação dos Recursos Naturais/métodos , Comportamento Alimentar/fisiologia , Imagens de Satélites/métodos , Spheniscidae/fisiologia , Distribuição Animal , Animais , Regiões Antárticas , Mudança Climática , Euphausiacea/fisiologia , Geografia , Ilhas , Densidade Demográfica , Dinâmica Populacional , Estações do Ano , Spheniscidae/classificação
2.
Conserv Biol ; 22(2): 252-66, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18402580

RESUMO

Many wide-ranging mammal species have experienced significant declines over the last 200 years; restoring these species will require long-term, large-scale recovery efforts. We highlight 5 attributes of a recent range-wide vision-setting exercise for ecological recovery of the North American bison (Bison bison) that are broadly applicable to other species and restoration targets. The result of the exercise, the "Vermejo Statement" on bison restoration, is explicitly (1) large scale, (2) long term, (3) inclusive, (4) fulfilling of different values, and (5) ambitious. It reads, in part, "Over the next century, the ecological recovery of the North American bison will occur when multiple large herds move freely across extensive landscapes within all major habitats of their historic range, interacting in ecologically significant ways with the fullest possible set of other native species, and inspiring, sustaining and connecting human cultures." We refined the vision into a scorecard that illustrates how individual bison herds can contribute to the vision. We also developed a set of maps and analyzed the current and potential future distributions of bison on the basis of expert assessment. Although more than 500,000 bison exist in North America today, we estimated they occupy <1% of their historical range and in no place express the full range of ecological and social values of previous times. By formulating an inclusive, affirmative, and specific vision through consultation with a wide range of stakeholders, we hope to provide a foundation for conservation of bison, and other wide-ranging species, over the next 100 years.


Assuntos
Bison , Conservação dos Recursos Naturais/métodos , Ecossistema , Animais , Demografia , América do Norte , Dinâmica Populacional
3.
Biomed Sci Instrum ; 43: 34-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17487054

RESUMO

The National Highway Traffic Safety Administration (NHTSA) has concluded that there is a relationship between roof intrusion and the risk of injury to belted occupants in rollovers events [1]. Previous testing on many different production vehicle types indicates that damage consistent with field rollover accidents can be achieved through inverted drop testing from small drop heights. It has been shown in previous drop test pairs with Hybrid III dummies, that the amount of roof intrusion is related to occupant neck injury [2,3]. In 1990, a study was reported by General Motors which involved 8 dolly rollover tests and 5 inverted drop tests performed on both production and rollcaged vehicles with Hybrid III dummies [4]. These studies were conducted to investigate the relationship between roof strength and occupant injury potential. In this paper, the authors further analyze the relationship between roof intrusion and occupant neck injury potential through inverted drop testing performed on Ford Econoline E-350 15-Passenger production and reinforced vans. Each of these van tests used Hybrid III test dummies in order to evaluate the resulting occupant injury potential in relation to the roof intrusion. The resulting roof intrusion and occupant neck loading experienced during the reinforced van drop test were significantly less than that of the production van test. As previously observed, the results of these tests indicate that the reduction of roof crush resulted in a direct reduction in neck loading and therefore an increase in occupant protection. Additionally, the inverse relationship between restraint loading and neck loading of the dummies was confirmed.


Assuntos
Aceleração/efeitos adversos , Acidentes de Trânsito , Análise de Falha de Equipamento/métodos , Lesões do Pescoço/etiologia , Lesões do Pescoço/fisiopatologia , Pescoço/fisiopatologia , Medição de Risco/métodos , Análise de Falha de Equipamento/instrumentação , Humanos , Manequins , Estimulação Física/efeitos adversos , Fatores de Risco
4.
Biomed Sci Instrum ; 42: 488-94, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16817656

RESUMO

The National Highway Traffic Safety Administration has concluded that there is a relationship between roof intrusion and the risk of injury to belted occupants in rollovers events. Previous testing on many different production vehicle types indicates that damage consistent with field rollover accidents can be achieved through inverted drop testing from small drop heights. It has been shown in previous drop test pairs with Hybrid III dummies, that the amount of roof intrusion is related to occupant neck injury. This paper analyzes inverted drop testing performed on Ford F250 Crew Cab production and reinforced pickups. Each of these pickup tests used Hybrid III test dummies in order to evaluate the occupant injury potential in relation to roof intrusion. The reinforced truck's residual crush was an order of magnitude less than the production truck crush. These tests indicated that the reduction of roof crush resulted in a direct reduction in neck loading and therefore an increase in occupant protection. In addition, it was found that the restraint loading was inversely related to the neck loading of the dummies.


Assuntos
Acidentes de Trânsito , Lesões do Pescoço/etiologia , Lesões do Pescoço/fisiopatologia , Estimulação Física/efeitos adversos , Medição de Risco/métodos , Ferimentos não Penetrantes/etiologia , Ferimentos não Penetrantes/fisiopatologia , Humanos , Manequins , Lesões do Pescoço/prevenção & controle , Estimulação Física/instrumentação , Estimulação Física/métodos , Fatores de Risco , Suporte de Carga , Ferimentos não Penetrantes/prevenção & controle
5.
Biomed Sci Instrum ; 41: 97-103, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15850089

RESUMO

Roof crush occurs and potentially contributes to serious or fatal occupant injury in 26% of rollovers. It is likely that glazing retention is related to the degree of roof crush experienced in rollover accidents. Occupant ejection (including partial ejection) is the leading cause of death and injury in rollover accidents. In fatal passenger car accidents involving ejection, 34% were ejected through the side windows. Side window glass retention during a rollover is likely to significantly reduce occupant ejections. The inverted drop test methodology is a test procedure to evaluate the structural integrity of roofs under loadings similar to those seen in real world rollovers. Recent testing on many different vehicle types indicates that damage consistent with field rollover accidents can be achieved through inverted drop testing at very small drop heights. Drop test comparisons were performed on 16 pairs of vehicles representing a large spectrum of vehicle types. Each vehicle pair includes a production vehicle and a vehicle with a reinforced roof structure dropped under the same test conditions. This paper offers several examples of post-production reinforcements to roof structures that significantly increase the crush resistance of the roof as measured by inverted drop tests. These modifications were implemented with minimal impact on vehicle styling, interior space and visual clearances. The results of these modifications indicate that roof crush can be mitigated by nearly an order of magnitude, as roof crush was reduced by 44-91% with only a 1-2.3% increase in vehicle weight. Additionally, this paper analyzes the glazing breakage patterns in the moveable tempered side windows on the side adjacent to the vehicle impact point in the inverted drop tests. A comparison is made between the production vehicles and the reinforced vehicles in order to determine if the amount roof crush is related to glazing integrity in the side windows. Lastly, two drop test pairs, performed with Hybrid III test dummies, indicates that the reduction of roof crush resulted in a direct reduction in neck loading and therefore an increase in occupant protection.


Assuntos
Prevenção de Acidentes/instrumentação , Acidentes de Trânsito/prevenção & controle , Automóveis , Análise de Falha de Equipamento/métodos , Equipamentos de Proteção , Ferimentos e Lesões/prevenção & controle , Prevenção de Acidentes/métodos , Desenho de Equipamento , Falha de Equipamento , Humanos , Estresse Mecânico
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