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1.
Conserv Physiol ; 11(1): coad095, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38107463

RESUMO

During the evolution of most marine mammals, fur as an insulator has been replaced with more buoyant, energy storing and streamlining blubber. By contrast, the sea otter (Enhydra lutris) relies on insulation from its dense, air-trapping pelage, which differs morphologically between natal and adult stages. In this study, we investigated the ontogenetic changes in thermal function of southern sea otter (Enhydra lutris nereis) pelts in air, in water, and when saturated with crude oil. Pelt thermal conductivity, thickness, and thermal resistance were measured for six age classes: neonate (<1 month), small pup (1-2 months), large pup (3-5 months), juvenile (6 months-1 year), subadult (1-3 years), and adult (4-9 years). Thermal conductivity was significantly higher for pelts in air than in water, with oiled pelts exhibiting the highest values (P < 0.001). Oiled pelts had the lowest thermal resistance, which suggests that regardless of age, all sea otters are vulnerable to the effects of oiling (P < 0.001). To scale up our laboratory findings, we used a volume-specific geometric model of conductive heat transfer for a simplified sea otter body, representing all tested age classes and treatments. Neonates, small pups, and large pups are more vulnerable to the effects of oiling compared with older age classes (P < 0.0001) due to a higher surface area-to-volume ratio. These results are consistent with the known thermal conductance values for adult sea otter pelts, yet this is the first time such thermal differences have been demonstrated in young otters. Overall, body size and age play a more important role in the thermal abilities of sea otters than previously thought.

2.
J Morphol ; 284(9): e21624, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37585225

RESUMO

Many animals exhibit morphological changes across ontogeny associated with adaptations to their environment. Sea otters (Enhydra lutris) have the densest fur of any animal, which is composed of guard hairs, intermediate hairs, and underhairs. Sea otters live in cold water environments, and their fur traps a layer of air to remain properly insulated, due to morphological adaptations that allow the hairs to trap air when submerged. When a sea otter is born, it has a natal pelage which it will eventually molt and replace with a pelt resembling the adult pelage. Past studies have investigated the morphology and hair density of adult sea otter fur, but these characteristics have not been measured for other age classes, including for the natal pelage. This study quantified ontogenetic changes in hair morphology of southern sea otter (E. lutris nereis) pelts. We measured guard hair length and circularity, shape of cuticular scales on guard hairs and underhairs, and overall hair density for sea otter pelts across six age classes: neonate (<1 month), small pup (1-2 months), large pup (3-5 months), juvenile (6 months-1 year), subadult (1-3 years), and adult (4-9 years). Neonate and small pup pelts had significantly longer guard hairs than older age classes. Natal pelage guard hairs were similarly shaped but smaller in diameter than adult guard hairs. Hairs of the natal pelage had similar cuticular scale patterns as adult hairs, indicating the importance of this structure for the function of the fur. Natal pelage had a lower hair density than the pelage of older age classes, with the adult pelage exhibiting the highest hair density. Overall, the morphological differences between natal and adult pelage in sea otters suggest functional differences that may make sea otter pups more vulnerable to heat loss.


Assuntos
Lontras , Animais , Muda , Aclimatação
3.
Public Underst Sci ; 26(2): 148-163, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27029766

RESUMO

In this article, we analyse a 2013 press conference hosting the world's first tasting of a laboratory grown hamburger. We explore this as a media event: an exceptional performative moment in which common meanings are mobilised and a connection to a shared centre of reality is offered. We develop our own theoretical contribution - the promotional public - to characterise the affirmative and partial patchwork of carefully selected actors invoked during the burger tasting. Our account draws on three areas of analysis: interview data with the scientists who developed the burger, media analysis of the streamed press conference itself and media analysis of social media during and following the event. We argue that the call to witness an experiment is a form of promotion and that such promotional material also offers an address that invokes a public with its attendant tensions.


Assuntos
Manipulação de Alimentos/métodos , Carne , Opinião Pública , Ciência , Tecnologia , Manipulação de Alimentos/instrumentação
4.
Child Abuse Negl ; 36(10): 701-10, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23083898

RESUMO

Methodologies to identify and enumerate children outside of family care vary as do the vulnerability categories of the children themselves. Children outside of family care is a broad term encompassing children absent of permanent family care, e.g., institutionalized children, children on/of the street, child-headed households, separated or unaccompanied children, trafficked children, children working in exploitive labor situations, etc. This paper reviews the various methodologies applied to identify and enumerate these often hidden and/or mobile populations. Methodologies that identify and enumerate children outside of family strive to meet two objectives: (1) to estimate the number and characteristics of a specific vulnerability category and (2) to determine eligibility to receive services. The paper reviews eight methodologies; six are categorized as survey sample methods (time-location sampling, capture recapture sampling, respondent driven sampling, the neighborhood method, household surveys, and establishment surveys) while two were labeled as data management systems (child labor management system, and databases of institutions). Each review includes a concise description of the methodology, its strengths and limitations, the most appropriate population it is suited to identify and/or enumerate, and any necessary conditions. Conclusions from these reviews advocate for tailoring a methodology (or a combination of methodologies) to the specific circumstances under which it is meant to identify or enumerate children outside of family care. In addition, further research and validation studies are needed to identify the conditions under which the strategies described here can be used and to develop appropriate protocols for utilization.


Assuntos
Coleta de Dados/métodos , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Populações Vulneráveis/classificação , Populações Vulneráveis/estatística & dados numéricos , Criança , Maus-Tratos Infantis/classificação , Maus-Tratos Infantis/estatística & dados numéricos , Coleta de Dados/estatística & dados numéricos , Humanos , Métodos
5.
J Sex Res ; 49(4): 362-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22720828

RESUMO

The gay gene was first identified in 1993 as a correlation between the genetic marker Xq28 and gay male sexuality. The results of this original study were never replicated, and the biological reality of such an entity remains hypothetical. However, despite such tenuous provenance, the gay gene has persisted as a reference in science news, popular science writings, and in press releases and editorials about biomedical research. An examination of the life of the gay gene in U.K. news media demonstrates that the gay gene has become an assumed back-story to genetic sexuality research over time, and that the critique of its very existence has been diminished. Latterly, the gay gene has entered into the online biomedical databases of the 21st century with the same pattern of persistence and diminishing critique. This article draws on an analysis of the U.K. press and online databases to represent the process through which the address of the gay gene has shifted and become an index of biomedicalization. The consequent unmooring of the gay gene from accountability and accuracy demonstrates that the organization of biomedical databases could benefit from greater cross-disciplinary attention.


Assuntos
Marcadores Genéticos , Homossexualidade Masculina/genética , Bases de Dados Factuais , Pesquisa em Genética , Humanos , Masculino , Meios de Comunicação de Massa , Reino Unido
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