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1.
Glob Chang Biol ; 27(19): 4849-4859, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34273224

RESUMO

Sea turtles are among several hundred species whose sex is determined by incubation conditions during critical developmental periods. Consequently, these marine reptiles may be vulnerable to global climate change, and under the assumption of continued climate warming, numerous studies pose dire predictions for future populations based primarily on hatchling sex ratio data. Alternatively, as long-lived species that take decades to reach maturity, without inherent coping mechanisms for such change, sea turtles could not have persisted across geological epochs. Globally, loggerhead Caretta caretta [Linnaeus, 1758] sea turtles occupy temperate zones, with ontogenetic development that spans the entirety of gyres associated with respective ocean basins. The largest rookery for this species occurs in the Northwest Atlantic Ocean (NWA) population, where a 30-year cycle in annual nest counts is reported through 2018. Complementary studies document a lagged association between these annual nest counts and the Atlantic Multidecadal Oscillation (AMO); however, the underlying mechanism for this association remains elusive. Therefore, objective 1 evaluated the effect of AMO-mediated cohort resonance on the demographic structure of a theoretical neritic assemblage under variable cohort abundance and female proportion but stable annual survival during 165-year runs (i.e., extent of AMO data). For objective 2, blood samples were used to assign sex to 2217 loggerhead sea turtles captured by research trawling (2000 to 2019) on the inner continental shelf from St. Augustine, FL (29.9°N) to Winyah Bay, SC (33.1°N). Shorter oceanic duration of less female-biased cohorts from the AMO cold phase synchronized peak adult male and adult female co-occurrence during subsequent warm phases three decades later. Grand sex ratio predicted from testosterone was 67% female (n = 1484), with a slight temporal female decline. Our findings suggest greater population sex ratio plasticity than predicted solely from terrestrial nesting data.


Assuntos
Tartarugas , Animais , Oceano Atlântico , Mudança Climática , Medo , Feminino , Masculino , Razão de Masculinidade , Estados Unidos
2.
Water Res ; 259: 121809, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38815338

RESUMO

Yearlong, event based, microbiological and chemical sampling was conducted at four public water supply well sites spanning a range of geologic settings and well depths to look for correlation between precipitation events and microbial occurrence. Near-continuous monitoring using autosamplers occurred just before, during, and after 5-7 sampling events triggered by rainfall and/or snowmelt. Microbial genetic material was noted at all four locations during all but one sampling event, but was exceedingly variable in time, where one sample would have no detections and the next sample could be a relatively high concentration. The highest microbial sums (microbial concentrations summed over an event) were observed during months in which precipitation exceeded historical averages. Extended wet conditions through the spring thaw resulted in the highest percentage of microbial positive samples, though at relatively low concentrations. Sampling events that followed drier than normal periods showed longer lag times between the onset of precipitation and microbial occurrence, as well as lower microbial detection rates. Although a general lag time pattern was observed at each site, the largest offset in time was observed at the site with the greatest depth to water. The study's temporally dense representation of drinking water pathogen characterization suggests that single event or infrequent periodic sampling of a drinking water supply cannot provide a representative characterization of the probability that pathogens are present, which likely has ramifications for calculating health risk assessments.


Assuntos
Água Potável , Monitoramento Ambiental , Microbiologia da Água , Água Potável/microbiologia , Monitoramento Ambiental/métodos , Poços de Água , Chuva , Estações do Ano , Abastecimento de Água , Bactérias/isolamento & purificação
3.
Sci Rep ; 13(1): 14444, 2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-37660203

RESUMO

Restricted range, and subsequently small population size, render Kemp's ridley sea turtles (Lepidochelys kempii) the most globally endangered sea turtle species. For at least two decades preceding conservation, high egg harvest rates reduced annual cohort recruitment. Despite > 50 years of dedicated conservation, annual nest counts remain well below a landmark 1947 level. Prior studies attribute less robust than anticipated nest count rebound to multiple contemporary concerns; however, analyses herein convey optimistic interpretation. In objective 1, improved analysis of the ratio of hatchlings to nests since 1966 suggested age structure stabilization as a more likely basis for nest count trends after 2005 than density-dependent effects. In objective 2, multiple regression revealed a lagged (≤ 13 years prior) climate influence on nests (adj. r2 = 0.82) and hatchlings per nest (adj. r2 = 0.94) during 2006-2022. In objectives 3 and 4, a simulator modeled population response to changes in a suite of demographic rates including survival. Across 32 models, high survival and dynamic cohort sex ratio, sexual maturity age, and the ratio of clutch frequency to remigration interval best explained nesting trends during 1966-2022. These novel findings provide alternative perspective for evaluating species recovery criteria and in turn refine future nest trend expectations.


Assuntos
Tartarugas , Animais , Clima , Espécies em Perigo de Extinção , Densidade Demográfica , Dinâmica Populacional
4.
Environ Toxicol Chem ; 42(6): 1309-1325, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36942377

RESUMO

Vitellogenin (VTG), an egg yolk precursor, is abnormally produced by male and juvenile oviparous species after exposure to estrogens. Plasma VTG in loggerhead sea turtles (Caretta caretta) helped us understand their reproductive maturation and investigate it as a biomarker of contaminant exposure. The presence of VTG was screened in plasma from 404 loggerheads from the northwestern Atlantic Ocean using a freshwater turtle antibody in western blots. The concentrations of VTG were semiquantified using band intensities calibrated to results from a loggerhead antibody enzyme-linked immunoassay. The detection and concentrations of VTG were in (from highest to lowest): nesting females, in-water adult females, subadult females, smaller females, unknown sex, and males. Loggerheads from this region begin vitellogenesis at ≅77 cm straight carapace length. We classified VTG expression as abnormal in nine male or juvenile turtles. Organochlorine contaminant (OC) concentrations were measured in blood and/or fat biopsies of some turtles. One abnormal VTG female had the second highest fat polychlorinated biphenyl (PCB) and 4,4'-dichlorodiphenyldichloroethylene concentrations compared among 43 VTG-negative juveniles. The nine VTG-abnormal turtles had average blood PCB concentrations 8.5% higher, but not significantly different, than 46 VTG-negative juveniles (p = 0.453). In turtles less than 77 cm, blood PCB concentrations were significantly, but weakly, correlated with semiquantified VTG concentrations (tau = 0.1, p = 0.004). Greater blood OC concentrations were found in adult females than in males, which motivated the creation of a conceptual model of OC, VTG, and hormone concentrations across a reproductive cycle. A decision tree is also provided incorporating VTG as a sexing tool. Abnormal VTG expression cannot conclusively be linked to endocrine disruption caused by these OC concentrations. Studies should further investigate causes of abnormal VTG expression in wild sea turtles. Environ Toxicol Chem 2023;42:1309-1325. © 2023 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.


Assuntos
Bifenilos Policlorados , Tartarugas , Animais , Feminino , Masculino , Vitelogeninas/metabolismo , Tartarugas/metabolismo , Bifenilos Policlorados/metabolismo , Anticorpos/metabolismo , Estrogênios/metabolismo
5.
Br J Psychiatry ; 200(5): 356-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22550327

RESUMO

Suicide rates are generally elevated after episodes of non-fatal self-harm, especially among older adults. Evidence suggests that non-fatal and fatal self-harm are more closely related in older than in younger adults. Older people who have self-harmed need specialist assessment followed by good short-term and long-term evidence-based care.


Assuntos
Comportamento Autodestrutivo/epidemiologia , Suicídio/estatística & dados numéricos , Feminino , Humanos , Masculino
6.
Ground Water ; 57(2): 329-336, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30155887

RESUMO

Fecal contamination by human and animal pathogens, including viruses, bacteria, and protozoa, is a potential human health hazard, especially with regards to drinking water. Pathogen occurrence in groundwater varies considerably in space and time, which can be difficult to characterize as sampling typically requires hundreds of liters of water to be passed through a filter. Here we describe the design and deployment of an automated sampler suited for hydrogeologically and chemically dynamic groundwater systems. Our design focused on a compact form to facilitate transport and quick deployment to municipal and domestic water supplies. We deployed a sampler to characterize water quality from a household well tapping a shallow fractured dolomite aquifer in northeast Wisconsin. The sampler was deployed from January to April 2017, and monitored temperature, nitrate, chloride, specific conductance, and fluorescent dissolved organic matter on a minute time step; water was directed to sequential microbial filters during three recharge periods that ranged from 5 to 20 days. Results from the automated sampler demonstrate the dynamic nature of the household water quality, especially with regard to microbial targets, which were shown to vary 1 to 2 orders of magnitude during a single sampling event. We believe assessments of pathogen occurrence and concentration, and related assessments of drinking well vulnerability, would be improved by the time-integrated characterization provided by this sampler.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Animais , Humanos , Qualidade da Água , Abastecimento de Água , Wisconsin
7.
Health Technol Assess ; 22(12): 1-222, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29532784

RESUMO

BACKGROUND: Self-harm in adolescents is common and repetition rates high. There is limited evidence of the effectiveness of interventions to reduce self-harm. OBJECTIVES: To assess the clinical effectiveness and cost-effectiveness of family therapy (FT) compared with treatment as usual (TAU). DESIGN: A pragmatic, multicentre, individually randomised controlled trial of FT compared with TAU. Participants and therapists were aware of treatment allocation; researchers were blind to allocation. SETTING: Child and Adolescent Mental Health Services (CAMHS) across three English regions. PARTICIPANTS: Young people aged 11-17 years who had self-harmed at least twice presenting to CAMHS following self-harm. INTERVENTIONS: Eight hundred and thirty-two participants were randomised to manualised FT delivered by trained and supervised family therapists (n = 415) or to usual care offered by local CAMHS following self-harm (n = 417). MAIN OUTCOME MEASURES: Rates of repetition of self-harm leading to hospital attendance 18 months after randomisation. RESULTS: Out of 832 young people, 212 (26.6%) experienced a primary outcome event: 118 out of 415 (28.4%) randomised to FT and 103 out of 417 (24.7%) randomised to TAU. There was no evidence of a statistically significant difference in repetition rates between groups (the hazard ratio for FT compared with TAU was 1.14, 95% confidence interval 0.87 to 1.49; p = 0.3349). FT was not found to be cost-effective when compared with TAU in the base case and most sensitivity analyses. FT was dominated (less effective and more expensive) in the complete case. However, when young people's and caregivers' quality-adjusted life-year gains were combined, FT incurred higher costs and resulted in better health outcomes than TAU within the National Institute for Health and Care Excellence cost-effectiveness range. Significant interactions with treatment, indicating moderation, were detected for the unemotional subscale on the young person-reported Inventory of Callous-Unemotional Traits (p = 0.0104) and the affective involvement subscale on the caregiver-reported McMaster Family Assessment Device (p = 0.0338). Caregivers and young people in the FT arm reported a range of significantly better outcomes on the Strengths and Difficulties Questionnaire. Self-reported suicidal ideation was significantly lower in the FT arm at 12 months but the same in both groups at 18 months. No significant unexpected adverse events or side effects were reported, with similar rates of expected adverse events across trial arms. CONCLUSIONS: For adolescents referred to CAMHS after self-harm, who have self-harmed at least once before, FT confers no benefits over TAU in reducing self-harm repetition rates. There is some evidence to support the effectiveness of FT in reducing self-harm when caregivers reported poor family functioning. When the young person themselves reported difficulty expressing emotion, FT did not seem as effective as TAU. There was no evidence that FT is cost-effective when only the health benefits to participants were considered but there was a suggestion that FT may be cost-effective if health benefits to caregivers are taken into account. FT had a significant, positive impact on general emotional and behavioural problems at 12 and 18 months. LIMITATIONS: There was significant loss to follow-up for secondary outcomes and health economic analyses; the primary outcome misses those who do not attend hospital following self-harm; and the numbers receiving formal FT in the TAU arm were higher than expected. FUTURE WORK: Evaluation of interventions targeted at subgroups of those who self-harm, longer-term follow-up and methods for evaluating health benefits for family groups rather than for individuals. TRIAL REGISTRATION: Current Controlled Trials ISRCTN59793150. FUNDING: This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 12. See the NIHR Journals Library website for further project information.


Assuntos
Psicoterapia/economia , Psicoterapia/métodos , Comportamento Autodestrutivo/terapia , Adolescente , Cuidadores/psicologia , Criança , Análise Custo-Benefício , Família/psicologia , Terapia Familiar/economia , Terapia Familiar/métodos , Feminino , Humanos , Masculino , Modelos Econométricos , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Projetos de Pesquisa , Medicina Estatal
8.
Lancet Psychiatry ; 5(3): 203-216, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29449180

RESUMO

BACKGROUND: Self-harm in adolescents is common and repetition occurs in a high proportion of these cases. Scarce evidence exists for effectiveness of interventions to reduce self-harm. METHODS: This pragmatic, multicentre, randomised, controlled trial of family therapy versus treatment as usual was done at 40 UK Child and Adolescent Mental Health Services (CAMHS) centres. We recruited young people aged 11-17 years who had self-harmed at least twice and presented to CAMHS after self-harm. Participants were randomly assigned (1:1) to receive manualised family therapy delivered by trained and supervised family therapists or treatment as usual by local CAMHS. Participants and therapists were aware of treatment allocation; researchers were masked. The primary outcome was hospital attendance for repetition of self-harm in the 18 months after group assignment. Primary and safety analyses were done in the intention-to-treat population. The trial is registered at the ISRCTN registry, number ISRCTN59793150. FINDINGS: Between Nov 23, 2009, and Dec 31, 2013, 3554 young people were screened and 832 eligible young people consented to participation and were randomly assigned to receive family therapy (n=415) or treatment as usual (n=417). Primary outcome data were available for 795 (96%) participants. Numbers of hospital attendances for repeat self-harm events were not significantly different between the groups (118 [28%] in the family therapy group vs 103 [25%] in the treatment as usual group; hazard ratio 1·14 [95% CI 0·87-1·49] p=0·33). Similar numbers of adverse events occurred in both groups (787 in the family therapy group vs 847 in the treatment as usual group). INTERPRETATION: For adolescents referred to CAMHS after self-harm, having self-harmed at least once before, our family therapy intervention conferred no benefits over treatment as usual in reducing subsequent hospital attendance for self-harm. Clinicians are therefore still unable to recommend a clear, evidence-based intervention to reduce repeated self-harm in adolescents. FUNDING: National Institute for Health Research Health Technology Assessment programme.


Assuntos
Terapia Familiar , Comportamento Autodestrutivo/terapia , Adolescente , Criança , Terapia Familiar/métodos , Feminino , Humanos , Masculino , Comportamento Autodestrutivo/psicologia , Inquéritos e Questionários , Resultado do Tratamento
9.
Environ Toxicol Chem ; 26(7): 1441-50, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17665684

RESUMO

Total mercury concentrations were measured in diamondback terrapin blood and scutes collected from four sites in South Carolina, USA, and at a superfund site in Brunswick, Georgia, USA. There was a strong correlation between mercury concentrations in the two terrapin body compartments (Kendall's tau = 0.79, p < 0.001). Mercury concentrations in terrapin scute and blood and in salt marsh periwinkles, Littoraria irrorata, were significantly higher in Brunswick (scute x = 3810.2 ng/g, blood x = 746.2 ng/g) than from all other sites (scute x = 309.5 ng/g, blood x = 43.2 ng/g, p < 0.001). Seasonal fluctuations of total mercury in the blood and scutes of terrapins collected in the Ashley River, South Carolina, were significantly lower in August than in April, June, or October in blood (p < 0.001); however, scute concentrations did not vary seasonally. Overall, we found higher concentrations of mercury in the scutes of females than males (n = 32, p < 0.05). Larger females may preferentially prey on larger food items, like large periwinkles, which had significantly higher mercury levels in their body tissues than smaller periwinkles (p < 0.001). Methylmercury levels in terrapin scutes were measured, revealing that 90% of the total mercury stored in this compartment was in the organic form. A methylmercury biomagnification factor of 173.5 was calculated from snails to terrapin scutes, and we found that mercury levels in scutes were representative of the mercury levels in other compartments of the ecosystem. These findings show that terrapin scutes are good predictors of mercury pollution and that this species could be used as a bioindicator for assessing mercury contamination of estuarine systems.


Assuntos
Monitoramento Ambiental/métodos , Mercúrio/análise , Poluentes Químicos da Água/análise , Animais , Feminino , Georgia , Masculino , South Carolina , Tartarugas
10.
PLoS One ; 11(8): e0160911, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27579608

RESUMO

Alterations have occurred and continue to manifest in the Earth's biota as a result of climate change. Animals exhibiting temperature dependent sex determination (TSD), including sea turtles, are perhaps most vulnerable to a warming of the Earth as highly skewed sex ratios can result, potentially leading to population extinction resulting from decreased male recruitment. Recent studies have begun to quantify climate change impacts to sea turtle populations, especially in terms of predicting effects on hatchling sex ratios. However, given the inherent difficulty in studying sex ratios at this life stage, a more accurate assessment of changes in population sex ratios might be derived by evaluating the juvenile portion of foraging aggregations. We investigated the long-term trend in sex ratio of a juvenile loggerhead (Caretta caretta) sea turtle population inhabiting Pamlico and Core Sounds, North Carolina, USA. We used plasma testosterone reference ranges measured using radioimmunoassay (RIA) to assign sex for 959 turtles and confirmed sex assignment of a subset (N = 58) of the sampled turtles through laparoscopic examination of their gonads. Our results demonstrate that for this particular population of loggerheads, sex ratios (3Females:1Male) had not significantly changed over a 10 year period (1998-2007), nor showed any significant difference among 5-cm straight carapace length (SCL) size classes. Ultimately, these findings provide a basis for comparison with future sex ratios, and highlight the importance of establishing similar long-term studies monitoring secondary, rather than primary, sex ratios, so that needed mitigation measures to climate change impacts can be implemented.


Assuntos
Aquecimento Global , Processos de Determinação Sexual , Razão de Masculinidade , Tartarugas , Animais , Feminino , Masculino , North Carolina
11.
PLoS One ; 10(10): e0138861, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26465620

RESUMO

Determining sex ratios of endangered populations is important for wildlife management, particularly species subject to sex-specific threats or that exhibit temperature-dependent sex determination. Sea turtle sex is determined by incubation temperature and individuals lack external sex-based traits until sexual maturity. Previous research utilized serum/plasma testosterone radioimmunoassays (RIA) to determine sex in immature/juvenile sea turtles. However, there has been a growing application of enzyme-linked immunosorbent assay (ELISA) for wildlife endocrinology studies, but no study on sea turtles has compared the results of ELISA and RIA. This study provides the first sex ratio for a threatened East Pacific green sea turtle (Chelonia mydas) foraging aggregation, a critical step for future management of this species. Here, we validate a testosterone ELISA and compare results between RIA and ELISA of duplicate samples. The ELISA demonstrated excellent correspondence with the RIA for providing testosterone concentrations for sex determination. Neither assay proved reliable for predicting the sex of reproductively active females with increased testosterone production. We then applied ELISA to examine the sex ratio of 69 green turtles foraging in San Diego Bay, California. Of 45 immature turtles sampled, sex could not be determined for three turtles because testosterone concentrations fell between the ranges for either sex (females: 4.1-113.1 pg/mL, males: 198.4-2,613.0 pg/mL) and these turtles were not subsequently recaptured to enable sex determination; using a Bayesian model to predict probabilities of turtle sex we predicted all three 'unknowns' were female (> 0.86). Additionally, the model assigned all turtles with their correct sex (if determined at recapture) with 100% accuracy. Results indicated a female bias (2.83F:1M) among all turtles in the aggregation; when focusing only on putative immature turtles the sex ratio was 3.5F:1M. With appropriate validation, ELISA sexing could be applied to other sea turtle species, and serve as a crucial conservation tool.


Assuntos
Ensaio de Imunoadsorção Enzimática/veterinária , Processos de Determinação Sexual/fisiologia , Razão de Masculinidade , Testosterona/sangue , Tartarugas/fisiologia , Distribuição Animal/fisiologia , Animais , Teorema de Bayes , California , Espécies em Perigo de Extinção , Ensaio de Imunoadsorção Enzimática/normas , Feminino , Masculino , Radioimunoensaio , Sensibilidade e Especificidade
12.
PLoS One ; 9(12): e114880, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25517114

RESUMO

Incubation temperature has significant developmental effects on oviparous animals, including affecting sexual differentiation for several species. Incubation temperature also affects traits that can influence survival, a theory that is verified in this study for the Northwest Atlantic loggerhead sea turtle (Caretta caretta). We conducted controlled laboratory incubations and experiments to test for an effect of incubation temperature on performance of loggerhead hatchlings. Sixty-eight hatchlings were tested in 2011, and 31 in 2012, produced from eggs incubated at 11 different constant temperatures ranging from 27°C to 33°C. Following their emergence from the eggs, we tested righting response, crawling speed, and conducted a 24-hour long swim test. The results support previous studies on sea turtle hatchlings, with an effect of incubation temperature seen on survivorship, righting response time, crawling speed, change in crawl speed, and overall swim activity, and with hatchlings incubated at 27°C showing decreased locomotor abilities. No hatchlings survived to be tested in both years when incubated at 32°C and above. Differences in survivorship of hatchlings incubated at high temperatures are important in light of projected higher sand temperatures due to climate change, and could indicate increased mortality from incubation temperature effects.


Assuntos
Temperatura , Tartarugas/fisiologia , Animais , Óvulo/fisiologia , Reprodução , Análise de Sobrevida
13.
J Comp Physiol B ; 178(4): 495-500, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18185934

RESUMO

Fatty acid concentrations found in the yolk of green sea turtles reflect differences in the diet of the mothers. All of the 12 fatty acids measured in yolk samples were significantly different between eggs produced from the pellet and wild-type diets. However, the relative pattern of yolk fatty acids in the green turtle mirrored those of other reptiles. Yolk samples contained mostly (63-67%) 14:0. 16:0, 16:1n-7 and 18:1n-9. Yolks from captive animals on pellet diet contained an additional 17.64% of the total yolk lipid as 12:0 and 18:2n-6. Wild yolks contained an extra 11.41% of lipid as 18:0 and 18:1n-7. Selection of fatty acids for the yolk should balance the energetic and anabolic needs of the embryo. Eggs are provisioned based on maternal metabolism of available nutrients and subtle differences between natural foods and those available in captivity could affect the viability of future eggs.


Assuntos
Ração Animal , Gorduras na Dieta/metabolismo , Gema de Ovo/metabolismo , Ácidos Graxos/metabolismo , Hydrocharitaceae , Tartarugas/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais Selvagens , Feminino , Fenômenos Fisiológicos da Nutrição Materna
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