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1.
Ecology ; 96(8): 2117-26, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26405737

RESUMO

The "landscape of fear" model has been proposed as a unifying concept in ecology, describing, in part, how animals behave and move about in their environment. The basic model predicts that as an animal's landscape changes from low to high risk of predation, prey species will alter their behavior to risk avoidance. However, studies investigating and evaluating the landscape of fear model across large spatial scales (tens to hundreds of thousands of square kilometers) in dynamic, open, aquatic systems involving apex predators and highly mobile prey are lacking. To address this knowledge gap, we investigated predator-prey relationships between. tiger sharks (Galeocerdo cuvier) and loggerhead turtles (Caretta caretta) in the North Atlantic Ocean. This included the use of satellite tracking to examine shark and turtle distributions as well as their surfacing behaviors under varying levels of home range overlap. Our findings revealed patterns that deviated from our a priori predictions based on the landscape of fear model. Specifically, turtles did not alter their surfacing behaviors to risk avoidance when overlap in shark-turtle core home range was high. However, in areas of high overlap with turtles, sharks exhibited modified surfacing behaviors that may enhance predation opportunity. We suggest that turtles may be an important factor in determining shark,distribution, whereas for turtles, other life history trade-offs may play a larger role in defining their habitat use. We propose that these findings are a result of both biotic and physically driven factors that independently or synergistically affect predator-prey interactions in this system. These results have implications for evolutionary biology, community ecology; and wildlife conservation. Further, given the difficulty in studying highly migratory marine species, our approach and conclusions may be applied to the study of other predator-prey systems.


Assuntos
Ecossistema , Medo , Comportamento Predatório/fisiologia , Tubarões/fisiologia , Tartarugas/fisiologia , Distribuição Animal , Animais , Oceano Atlântico , Reação de Fuga , Estações do Ano , Astronave , Telemetria
2.
Thorax ; 68(11): 1072-4, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23471697

RESUMO

UNLABELLED: Records were reviewed (n=1052) for patients admitted to a large general intensive care unit (GICU) and examined for HIV testing criteria published in UK national testing guidelines (UKNG). All actual tests sent from GICU were also examined for comparison. Strict application of the UKNG revealed 30% of patients met criteria for HIV testing on admission to GICU. With pragmatic application, 18% of admissions met criteria for testing. Less than 5% of admissions were actually tested when no testing guideline was adopted. DISCUSSION: The UKNG can be adopted in a representative GICU to increase HIV testing rate by 4-6-fold.


Assuntos
Infecções por HIV/diagnóstico , Hospitalização/tendências , Unidades de Terapia Intensiva/estatística & dados numéricos , Programas de Rastreamento/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Feminino , Infecções por HIV/terapia , Humanos , Masculino , Estudos Retrospectivos , Reino Unido
3.
PLoS One ; 15(4): e0231325, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32282844

RESUMO

Population assessments conducted at reproductive sites of migratory species necessitate understanding the foraging-area origins of breeding individuals. Without this information, efforts to contextualize changes in breeding populations and develop effective management strategies are compromised. We used stable isotope analysis of tissue samples collected from loggerhead sea turtles (Caretta caretta) nesting at seven sites in the Northern Recovery Unit (NRU) of the eastern United States (North Carolina, South Carolina and Georgia) to assign females to three separate foraging areas in the Northwest Atlantic Ocean (NWA). We found that the majority of the females at NRU nesting sites (84.4%) use more northern foraging areas in the Mid-Atlantic Bight, while fewer females use more proximate foraging areas in the South Atlantic Bight (13.4%) and more southerly foraging areas in the Subtropical Northwest Atlantic (2.2%). We did not find significant latitudinal or temporal trends in the proportions of NRU females originating from different foraging areas. Combining these findings with previous data from stable isotope and satellite tracking studies across NWA nesting sites showed that variation in the proportion of adult loggerheads originating from different foraging areas is primarily related differences between recovery units: individuals in the NRU primarily use the Mid-Atlantic Bight foraging area, while individuals from the three Florida recovery units primarily use the Subtropical Northwest Atlantic and Eastern Gulf of Mexico foraging areas. Because each foraging area is associated with its own distinct ecological characteristics, environmental fluctuations and anthropogenic threats that affect the abundance and productivity of individuals at nesting sites, this information is critical for accurately evaluating population trends and developing effective region-specific management strategies.


Assuntos
Cruzamento , Tartarugas/fisiologia , Migração Animal , Animais , Oceano Atlântico , Feminino , Comportamento de Nidação , Tartarugas/crescimento & desenvolvimento
4.
J Wildl Dis ; 45(1): 41-56, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19204334

RESUMO

The health status of 83 loggerhead sea turtles (Caretta caretta; 39 foraging, 31 nesting, and 13 stranded turtles) was analyzed using physical examinations, hematology, plasma biochemistry, plasma protein electrophoresis, and toxicologic parameters. Significant differences were noted in a number of health parameters between turtles exhibiting each of these behaviors. On physical examinations, stranded turtles had the highest prevalence of heavy carapace epibiont loads, miscellaneous abnormalities, emaciation, and weakness. Differences in hematologic values included a lower packed cell volume, higher number of lymphocytes, and lower number of monocytes in stranded turtles; lower white blood cell counts in foraging turtles; and significant differences in total solid values among turtles exhibiting all behaviors with the lowest values in stranded turtles and the highest values in nesting turtles. Differences in plasma biochemistry values included the highest uric acid, creatine kinase, and CO(2) values in stranded turtles; the highest glucose and potassium values in foraging turtles; and the highest cholesterol and triglyceride values, and lowest alanine aminotransferase, in nesting turtles. Differences in total protein, albumin, and globulin were found using plasma biochemistry values, with lowest values in stranded turtles and highest values in nesting females, whereas differences in blood urea nitrogen between turtles included the lowest values in nesting turtles and the highest in foraging turtles. Plasma organochlorine and polychlorinated biphenyl levels were below their limits of quantification in the 39 foraging, 11 nesting, and three stranded turtles tested. A statistically significant difference was noted in the level of whole blood mercury between the 23 foraging and 12 nesting turtles tested. There was no difference in arsenic or lead levels between turtles exhibiting any of the three behaviors. Although a few limitations exist with the present study and include unknown ambient temperatures, turtle handling times that varied from 15 min to 53 min per turtle, and the use of a different laboratory for processing complete blood counts and plasma biochemistries in stranded versus foraging and nesting turtles, we provide baseline blood values for two cohorts (foraging and nesting) of loggerhead sea turtles on the coast of Georgia. Additionally, we demonstrate significant differences in clinical findings and blood parameters between foraging, nesting, and stranded loggerhead turtles in the region.


Assuntos
Nível de Saúde , Tartarugas/sangue , Fatores Etários , Animais , Animais Selvagens/sangue , Contagem de Células Sanguíneas/veterinária , Análise Química do Sangue/veterinária , Feminino , Georgia , Testes Hematológicos/veterinária , Masculino , Valores de Referência , Tartarugas/fisiologia
5.
Echo Res Pract ; 2(2): K29-32, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26693338

RESUMO

UNLABELLED: The present case is an unusual one of a 21-year-old female with a primary osteosarcoma and left lung metastasis presenting following a witnessed pulseless electrical activity cardiac arrest. The electrocardiogram was unremarkable. A computed tomography pulmonary angiogram (CTPA) demonstrated a tumour within the left inferior pulmonary veins. Transthoracic echocardiography (TTE) revealed a severely hypokinetic left ventricle and a multi-lobulated, mobile mass arising from one of the left pulmonary veins which prolapsed to varying degrees on a beat-to-beat basis back and forth through the mitral valve into the left ventricle (during ventricular diastole) and retracted back into the left atrium (during ventricular systole). The present case demonstrates the importance of performing TTE in an emergency presentation, its influence on diagnosis and, in the present case, its usefulness in aiding the decision to withdraw life-sustaining treatments. It also highlights the importance of considering urgent intervention for a tumour seen to prolapse through the mitral valve because of the real risk of acute obstruction. LEARNING POINTS: The present case emphasises the importance of thorough clinical assessment in triggering TTE assessment in a critical care setting.TTE is a portable, radiation-free imaging modality that can aid rapid diagnosis in a deteriorating patient and guide an informed management plan.Many district general hospitals in the UK lack cardiology support and access to echocardiography 'out-of-hours'. TTE, in the hands of an experienced operator, is an invaluable tool in the emergency assessment and management of critically unwell patients and should be available 24 h a day, 7 days a week.Echosonographers and physicians seeing similar dynamic tumour pathology with variable transmission through the mitral valve should bear in mind acute obstruction as a potential consequence and thus consider urgent intervention.

6.
Econ Hum Biol ; 12: 83-97, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23787352

RESUMO

This paper explores the relationship between intertemporal discounting and body weight, using stated preference measures of intertemporal discounting, and the body mass index (BMI) to represent relative body weight. The empirical analysis uses Australian data obtained in 2008 through the South Australian Health Omnibus Survey. A quantile regression analysis is used to allow the marginal effects of the explanatory variables on BMI to vary across the conditional BMI distribution. It is shown that an indicator of intertemporal discounting elicited from a hypothetical monetary trade-off has a significant positive relationship with BMI. This relationship appears to be stronger in the upper quantiles, but there is insufficient statistical evidence for this difference. Evidence is presented that intertemporal discounting is a risk factor for increased BMI with a magnitude of effect comparable to more commonly recognized risk factors such as income and education. However there is no significant relationship found between BMI and an alternative indicator of intertemporal discounting elicited from trade-offs in health status.


Assuntos
Índice de Massa Corporal , Comportamento de Escolha , Estilo de Vida , Obesidade/etiologia , Indicadores Básicos de Saúde , Inquéritos Epidemiológicos , Humanos , Entrevistas como Assunto , Modelos Teóricos , Análise de Regressão , Fatores de Risco , Fatores Socioeconômicos , Austrália do Sul , Fatores de Tempo
7.
Mol Ecol Resour ; 11(1): 110-5, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21429107

RESUMO

Tagging studies on nesting beaches are commonly used to estimate nesting frequency, remigration interval and nesting population size for marine turtle rookeries. Estimates of these demographic parameters from tagging projects may be biased because of the small scale of tagging efforts relative to female nest site fidelity and the logistical difficulty of intercepting all nesting females. Therefore, alternative and supplemental means of individual identification of nesting females are required. We demonstrate that maternal nuclear microsatellite DNA can be isolated from unincubated eggshells of the loggerhead sea turtle (Caretta caretta) through comparison of DNA extracted from 59 eggs collected within 15 h of oviposition and DNA derived from skin samples from respective nesting females. Scorable microsatellite genotypes were produced in 897 of 994 (90.2%) single-locus egg amplifications attempted. Among eggs from known females, 730 of 748 (97.6%) single-locus, egg-derived genotypes matched the respective skin-derived genotypes. Allelic dropout was the most common type of error, followed by the presence of nonmaternal, presumably paternal, alleles. Genotypes derived from unincubated eggshells permit individual assignment of nests and therefore demographic parameter estimates for loggerhead turtle nesting populations, despite genotyping errors that require further optimization. Although sampling unincubated eggs is destructive, this technique is noninvasive to nesting females and is applicable in marine turtle population genetics studies when individual resolution is required but direct interception of nesting females is undesirable or logistically infeasible.


Assuntos
Núcleo Celular/genética , DNA/genética , Genética Populacional/métodos , Óvulo/citologia , Tartarugas/genética , Animais , Feminino , Genótipo , Repetições de Microssatélites , Comportamento de Nidação , Reprodução , Especificidade da Espécie , Tartarugas/fisiologia
8.
J Wildl Dis ; 46(1): 111-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20090024

RESUMO

An increase in the incidence of debilitated loggerhead sea turtle (Caretta caretta) strandings in the southeastern United States has been observed in recent years. These turtles are characterized by emaciation and heavy burdens of external and internal parasites, and bacterial infections, but the underlying cause of their condition is unknown. To investigate further the causes of these strandings, a health assessment was performed on stranded, debilitated loggerhead turtles, and contaminant concentrations in various tissues were compared to those from healthy turtles. This portion of the study investigated the potential role of mercury (Hg) toxicity in the debilitated condition described above. Hematocrit, total protein, albumin, globulin, glucose, calcium, lymphocyte counts, heterophil:lymphocyte ratios, aspartate aminotransferase, uric acid, sodium, and chloride were altered in debilitated loggerheads relative to healthy animals. However, none of the aforementioned health indicators correlated with Hg concentrations in either red blood cells (RBCs) or plasma. The Hg concentration in RBCs was 129+/-72 (mean+/-standard deviation) times higher than in plasma, causing a significant dilution of Hg in whole blood due to extreme anemia. Mercury concentrations in RBCs (73.7+/-21.2 ng/g) and scutes (455+/-57 ng/g) from debilitated turtles were similar to or lower than those reported for healthy animals, indicating no elevation in Hg exposure before and during the progression of this condition. These findings suggest that Hg toxicity does not play a role in the debilitated loggerhead condition observed in the southeastern United States.


Assuntos
Nível de Saúde , Mercúrio/análise , Tartarugas , Animais , Animais Selvagens/sangue , Oceano Atlântico , Contagem de Células Sanguíneas/veterinária , Análise Química do Sangue/veterinária , Carga Corporal (Radioterapia) , Estudos de Casos e Controles , Doença Crônica , Exposição Ambiental , Monitoramento Ambiental , Hematócrito/veterinária , Sistema Imunitário/efeitos dos fármacos , Mercúrio/toxicidade , Sudeste dos Estados Unidos , Distribuição Tecidual , Tartarugas/sangue , Tartarugas/fisiologia , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/sangue
9.
Med J Aust ; 191(10): 530-4, 2009 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-19912083

RESUMO

OBJECTIVE: To measure the level of functional health literacy (FHL) in an Australian population, and to explore the level of risk associated with level of FHL. DESIGN, SETTING AND PARTICIPANTS: Cross-sectional, random population survey administered to 2824 South Australians aged>or=15 years, September-October 2008. MAIN OUTCOME MEASURES: Newest Vital Sign as a measure of FHL, self-reported general health status, and use of health services. RESULTS: 24% of respondents were at risk of limited FHL, and 21% had a high likelihood of inadequate FHL; this increased with age (>or=65 years, 50% v 25-44 years, 11%). In multiple logistic regression models, a high likelihood of inadequate FHL was significantly more common among those with lower education (left schoolor=65 years with inadequate FHL were more likely to have been admitted to hospital (OR, 2.2; 95% CI, 1.1-4.5). CONCLUSION: Many Australians are likely to have limited health literacy, and this is a risk to effective health care delivery and health improvement across the community.


Assuntos
Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Nível de Saúde , Adolescente , Adulto , Idoso , Austrália , Estudos Transversais , Feminino , Serviços de Saúde/estatística & dados numéricos , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Características de Residência , Fatores de Risco , Fatores Socioeconômicos , Adulto Jovem
10.
Obes Res Clin Pract ; 2(2): 71-142, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24351726

RESUMO

SUMMARY: As obesity becomes a major health and economic issue of the current age, interventions and policies are being targeted to influence individuals' diet and exercise behaviors. Examining the deviations of reality from a baseline model of rational choice provides insights into the economic rationales for interventions to modify individuals' choices. In addition to the more classical economic rationales for intervention, insights from behavioral economics and psychology have recently led to a focus on the role of time-inconsistent preferences, in particular present-biased preferences, in the choices that lead to obesity. While individuals can use self-control techniques to mitigate the problem, there is also potential for targeted interventions and policies to improve the welfare of individuals. Further interdisciplinary research in the area may lead to behavioral obesity interventions tailored to individuals' incentives, resulting in higher compliance rates.:

11.
Mol Ecol ; 13(12): 3797-808, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15548292

RESUMO

Juvenile loggerhead turtles (Caretta caretta) from West Atlantic nesting beaches occupy oceanic (pelagic) habitats in the eastern Atlantic and Mediterranean, whereas larger juvenile turtles occupy shallow (neritic) habitats along the continental coastline of North America. Hence the switch from oceanic to neritic stage can involve a trans-oceanic migration. Several researchers have suggested that at the end of the oceanic phase, juveniles are homing to feeding habitats in the vicinity of their natal rookery. To test the hypothesis of juvenile homing behaviour, we surveyed 10 juvenile feeding zones across the eastern USA with mitochondrial DNA control region sequences (N = 1437) and compared these samples to potential source (nesting) populations in the Atlantic Ocean and Mediterranean Sea (N = 465). The results indicated a shallow, but significant, population structure of neritic juveniles (PhiST = 0.0088, P = 0.016), and haplotype frequency differences were significantly correlated between coastal feeding populations and adjacent nesting populations (Mantel test R2 = 0.52, P = 0.001). Mixed stock analyses (using a Bayesian algorithm) indicated that juveniles occurred at elevated frequency in the vicinity of their natal rookery. Hence, all lines of evidence supported the hypothesis of juvenile homing in loggerhead turtles. While not as precise as the homing of breeding adults, this behaviour nonetheless places juvenile turtles in the vicinity of their natal nesting colonies. Some of the coastal hazards that affect declining nesting populations may also affect the next generation of turtles feeding in nearby habitats.


Assuntos
Variação Genética , Comportamento de Retorno ao Território Vital/fisiologia , Reprodução/fisiologia , Comportamento Sexual Animal/fisiologia , Tartarugas/fisiologia , Análise de Variância , Animais , Oceano Atlântico , Teorema de Bayes , Primers do DNA , DNA Mitocondrial/genética , Demografia , Comportamento Alimentar/fisiologia , Haplótipos/genética , América do Norte , Análise de Sequência de DNA , Tartarugas/genética
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