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1.
Sci Rep ; 14(1): 10715, 2024 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-38782960

RESUMO

The large nose adorned by adult male proboscis monkeys is hypothesised to serve as an audiovisual signal of sexual selection. It serves as a visual signal of male quality and social status, and as an acoustic signal, through the expression of loud, low-formant nasalised calls in dense rainforests, where visibility is poor. However, it is unclear how the male proboscis monkey nasal complex, including the internal structure of the nose, plays a role in visual or acoustic signalling. Here, we use cranionasal data to assess whether large noses found in male proboscis monkeys serve visual and/or acoustic signalling functions. Our findings support a visual signalling function for male nasal enlargement through a relatively high degree of nasal aperture sexual size dimorphism, the craniofacial region to which nasal soft tissue attaches. We additionally find nasal aperture size increases beyond dental maturity among male proboscis monkeys, consistent with the visual signalling hypothesis. We show that the cranionasal region has an acoustic signalling role through pronounced nasal cavity sexual shape dimorphism, wherein male nasal cavity shape allows the expression of loud, low-formant nasalised calls. Our findings provide robust support for the male proboscis monkey nasal complex serving both visual and acoustic functions.


Assuntos
Caracteres Sexuais , Animais , Masculino , Cavidade Nasal/anatomia & histologia , Cavidade Nasal/fisiologia , Nariz/anatomia & histologia , Comunicação Animal , Acústica , Crânio/anatomia & histologia , Vocalização Animal/fisiologia , Feminino
2.
Nature ; 608(7922): 275-286, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35948707

RESUMO

The East Antarctic Ice Sheet contains the vast majority of Earth's glacier ice (about 52 metres sea-level equivalent), but is often viewed as less vulnerable to global warming than the West Antarctic or Greenland ice sheets. However, some regions of the East Antarctic Ice Sheet have lost mass over recent decades, prompting the need to re-evaluate its sensitivity to climate change. Here we review the response of the East Antarctic Ice Sheet to past warm periods, synthesize current observations of change and evaluate future projections. Some marine-based catchments that underwent notable mass loss during past warm periods are losing mass at present but most projections indicate increased accumulation across the East Antarctic Ice Sheet over the twenty-first century, keeping the ice sheet broadly in balance. Beyond 2100, high-emissions scenarios generate increased ice discharge and potentially several metres of sea-level rise within just a few centuries, but substantial mass loss could be averted if the Paris Agreement to limit warming below 2 degrees Celsius is satisfied.


Assuntos
Modelos Climáticos , Aquecimento Global , Camada de Gelo , Temperatura , Regiões Antárticas , Previsões , Aquecimento Global/história , Aquecimento Global/prevenção & controle , Aquecimento Global/estatística & dados numéricos , História do Século XXI , Elevação do Nível do Mar/história , Elevação do Nível do Mar/estatística & dados numéricos
3.
Nat Commun ; 12(1): 2015, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795667

RESUMO

The most rapid global sea-level rise event of the last deglaciation, Meltwater Pulse 1A (MWP-1A), occurred ∼14,650 years ago. Considerable uncertainty regarding the sources of meltwater limits understanding of the relationship between MWP-1A and the concurrent fast-changing climate. Here we present a data-driven inversion approach, using a glacio-isostatic adjustment model to invert for the sources of MWP-1A via sea-level constraints from six geographically distributed sites. The results suggest contributions from Antarctica, 1.3 m (0-5.9 m; 95% probability), Scandinavia, 4.6 m (3.2-6.4 m) and North America, 12.0 m (5.6-15.4 m), giving a global mean sea-level rise of 17.9 m (15.7-20.2 m) in 500 years. Only a North American dominant scenario successfully predicts the observed sea-level change across our six sites and an Antarctic dominant scenario is firmly refuted by Scottish isolation basin records. Our sea-level based results therefore reconcile with field-based ice-sheet reconstructions.

4.
Nat Commun ; 10(1): 503, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30700704

RESUMO

Recent studies suggest that Antarctica has the potential to contribute up to ~15 m of sea-level rise over the next few centuries. The evolution of the Antarctic Ice Sheet is driven by a combination of climate forcing and non-climatic feedbacks. In this review we focus on feedbacks between the Antarctic Ice Sheet and the solid Earth, and the role of these feedbacks in shaping the response of the ice sheet to past and future climate changes. The growth and decay of the Antarctic Ice Sheet reshapes the solid Earth via isostasy and erosion. In turn, the shape of the bed exerts a fundamental control on ice dynamics as well as the position of the grounding line-the location where ice starts to float. A complicating issue is the fact that Antarctica is situated on a region of the Earth that displays large spatial variations in rheological properties. These properties affect the timescale and strength of feedbacks between ice-sheet change and solid Earth deformation, and hence must be accounted for when considering the future evolution of the ice sheet.

5.
Aust J Rural Health ; 24(4): 271-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26689597

RESUMO

OBJECTIVE: To describe outcomes of a model of service learning in interprofessional learning (IPL) aimed at developing a sustainable model of training that also contributed to service strengthening. DESIGN: A total of 57 semi-structured interviews with key informants and document review exploring the impacts of interprofessional student teams engaged in locally relevant IPL activities. SETTING: Six rural towns in South East New South Wales. PARTICIPANTS: Local facilitators, staff of local health and other services, health professionals who supervised the 89 students in 37 IPL teams, and academic and administrative staff. MAIN OUTCOME MEASURES: Perceived benefits as a consequence of interprofessional, service-learning interventions in these rural towns. RESULTS: Reported outcomes included increased local awareness of a particular issue addressed by the team; improved communication between different health professions; continued use of the team's product or a changed procedure in response to the teams' work; and evidence of improved use of a particular local health service. CONCLUSIONS: Given the limited workforce available in rural areas to supervise clinical IPL placements, a service-learning IPL model that aims to build social capital may be a useful educational model.


Assuntos
Pessoal de Saúde/educação , Relações Interprofissionais , Modelos Organizacionais , Serviços de Saúde Rural , Capital Social , Estudantes de Medicina , Humanos , Entrevistas como Assunto , New South Wales , Pesquisa Qualitativa
6.
J Allied Health ; 43(3): 176-83, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25194065

RESUMO

UNLABELLED: Australia has been relatively slow in adopting interprofessional learning (IPL) to prepare health professional students for future collaborative professional practice. A collaborative project between two universities placed senior health professional students in IPL teams in rural southeast New South Wales, Australia, to work on small, locally relevant projects with guidance from locally appointed IPL facilitators. This paper reports on the initial stages of an evaluation of this rural-based IPL intervention using the modified Freeth/Kirkpatrick's 4-level evaluation model. METHODS: Students' responses were collected using a debriefing questionnaire, the Interprofessional Education Perception (IEPS) and Team Performance (TPS) scales. An audience feedback questionnaire was structured around project objectives. RESULTS: Seventy-nine students participated in 33 IPL teams during the evaluation period included in this study. IEPS scores increased with participation (t=2.803; p=0.007). The TPS showed a statistically significant difference between teams (ANOVA, F(31,45) = 1.982, p=0.018( and a trend toward agreement with audience perceptions of team performance. CONCLUSIONS: The evaluation demonstrated positive short-term outcomes suggesting benefits of this applied approach in preparing students to work interprofessionally.


Assuntos
Ocupações em Saúde/educação , Equipe de Assistência ao Paciente/organização & administração , Seleção de Pessoal , Serviços de Saúde Rural , Feminino , Humanos , Relações Interprofissionais , Masculino , New South Wales , Inquéritos e Questionários , Recursos Humanos
7.
Nature ; 498(7452): 51-9, 2013 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-23739423

RESUMO

Since the 2007 Intergovernmental Panel on Climate Change Fourth Assessment Report, new observations of ice-sheet mass balance and improved computer simulations of ice-sheet response to continuing climate change have been published. Whereas Greenland is losing ice mass at an increasing pace, current Antarctic ice loss is likely to be less than some recently published estimates. It remains unclear whether East Antarctica has been gaining or losing ice mass over the past 20 years, and uncertainties in ice-mass change for West Antarctica and the Antarctic Peninsula remain large. We discuss the past six years of progress and examine the key problems that remain.


Assuntos
Mudança Climática/estatística & dados numéricos , Camada de Gelo , Incerteza , Ar , Regiões Antárticas , Simulação por Computador , Groenlândia , Neve , Temperatura
8.
Science ; 338(6111): 1183-9, 2012 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-23197528

RESUMO

We combined an ensemble of satellite altimetry, interferometry, and gravimetry data sets using common geographical regions, time intervals, and models of surface mass balance and glacial isostatic adjustment to estimate the mass balance of Earth's polar ice sheets. We find that there is good agreement between different satellite methods--especially in Greenland and West Antarctica--and that combining satellite data sets leads to greater certainty. Between 1992 and 2011, the ice sheets of Greenland, East Antarctica, West Antarctica, and the Antarctic Peninsula changed in mass by -142 ± 49, +14 ± 43, -65 ± 26, and -20 ± 14 gigatonnes year(-1), respectively. Since 1992, the polar ice sheets have contributed, on average, 0.59 ± 0.20 millimeter year(-1) to the rate of global sea-level rise.


Assuntos
Mudança Climática , Camada de Gelo , Regiões Antárticas , Sistemas de Informação Geográfica , Groenlândia
9.
Nature ; 491(7425): 586-9, 2012 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-23086145

RESUMO

Recent estimates of Antarctica's present-day rate of ice-mass contribution to changes in sea level range from 31 gigatonnes a year (Gt yr(-1); ref. 1) to 246 Gt yr(-1) (ref. 2), a range that cannot be reconciled within formal errors. Time-varying rates of mass loss contribute to this, but substantial technique-specific systematic errors also exist. In particular, estimates of secular ice-mass change derived from Gravity Recovery and Climate Experiment (GRACE) satellite data are dominated by significant uncertainty in the accuracy of models of mass change due to glacial isostatic adjustment (GIA). Here we adopt a new model of GIA, developed from geological constraints, which produces GIA rates systematically lower than those of previous models, and an improved fit to independent uplift data. After applying the model to 99 months (from August 2002 to December 2010) of GRACE data, we estimate a continent-wide ice-mass change of -69 ± 18 Gt yr(-1) (+0.19 ± 0.05 mm yr(-1) sea-level equivalent). This is about a third to a half of the most recently published GRACE estimates, which cover a similar time period but are based on older GIA models. Plausible GIA model uncertainties, and errors relating to removing longitudinal GRACE artefacts ('destriping'), confine our estimate to the range -126 Gt yr(-1) to -29 Gt yr(-1) (0.08-0.35 mm yr(-1) sea-level equivalent). We resolve 26 independent drainage basins and find that Antarctic mass loss, and its acceleration, is concentrated in basins along the Amundsen Sea coast. Outside this region, we find that West Antarctica is nearly in balance and that East Antarctica is gaining substantial mass.


Assuntos
Gravitação , Camada de Gelo , Modelos Teóricos , Comunicações Via Satélite , Água do Mar/análise , Regiões Antárticas , Artefatos , Congelamento , Oceanos e Mares , Projetos de Pesquisa , Fatores de Tempo , Incerteza
10.
Case Rep Dermatol ; 3(2): 175-80, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-22059074

RESUMO

Giant warts are infrequent dermatological viral infections caused by Papillomavirus (HPV) in immune-compromised patients. Treatment may often be difficult and unsatisfactory, either by surgery or cytotoxic agents, because of poor immune control of viral activity in such hosts. Here we report on the case of a patient with advanced and persistent immune suppression caused by HIV disease, who developed a monstrous wart covering the entirety of the radial district of his right hand. He was completely healed after a long treatment with traditional Chinese acupuncture, in spite of minimal immune recovery induced by efficacious antiretroviral therapy. To the best of our knowledge, therefore, the present report may be the first direct clinical evidence that acupuncture may be effective in the treatment of cutaneous warts also in HIV-infected patients.

11.
J Hum Lact ; 27(3): 250-61, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21788654

RESUMO

The Gudaga Study is a prospective, longitudinal birth cohort study of Australian urban Aboriginal children. Mothers of Aboriginal infants were recruited using a survey of all mothers admitted to the maternity ward of an outer urban hospital in Sydney. These data established initiation rates among Gudaga infants and those of non-Aboriginal infants born locally (64.7% and 75.2%, respectively) and factors associated with breastfeeding. Older (relative risk, 1.24; confidence interval, 1.01-1.44), more educated (relative risk, 1.30; confidence interval, 1.11-1.48) mothers who intended to breastfeed (relative risk, 2.22; confidence interval, 2.12-2.3) were more likely to breastfeed. Smokers (relative risk, 0.72) and mothers of Aboriginal infants (relative risk, 0.78) were less likely to initiate breastfeeding. Breastfeeding rates for Gudaga infants dropped rapidly, with 26.3% breastfeeding at 2 months. Local health services providers can benefit from such information as they target relevant prenatal, perinatal, and postnatal services for Aboriginal mothers and their infants.


Assuntos
Aleitamento Materno , Havaiano Nativo ou Outro Ilhéu do Pacífico/psicologia , Havaiano Nativo ou Outro Ilhéu do Pacífico/estatística & dados numéricos , Austrália/epidemiologia , Aleitamento Materno/epidemiologia , Aleitamento Materno/etnologia , Aleitamento Materno/psicologia , Aleitamento Materno/estatística & dados numéricos , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Estudos Prospectivos , Características de Residência/estatística & dados numéricos , Fatores de Tempo , Desmame
12.
Med Phys ; 37(9): 4530-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20964170

RESUMO

PURPOSE: To compare and evaluate intensity-based registration methods for computation of serial x-ray mammogram correspondence. METHODS: X-ray mammograms were simulated from MRIs of 20 women using finite element methods for modeling breast compressions and employing a MRI/x-ray appearance change model. The parameter configurations of three registration methods, affine, fluid, and free-form deformation (FFD), were optimized for registering x-ray mammograms on these simulated images. Five mammography film readers independently identified landmarks (tumor, nipple, and usually two other normal features) on pairs of diagnostic and corresponding prediagnostic digitized images from 52 breast cancer cases. Landmarks were independently reidentified by each reader. Target registration errors were calculated to compare the three registration methods using the reader landmarks as a gold standard. Data were analyzed using multilevel methods. RESULTS: Between-reader variability varied with landmark (p < 0.01) and screen (p = 0.03), with between-reader mean distance (mm) in point location on the diagnostic/prediagnostic images of 2.50 (95% CI 1.95, 3.15)/2.84 (2.24, 3.55) for nipples and 4.26 (3.43, 5.24)/4.76 (3.85, 5.84) for tumors. Registration accuracy was sensitive to the type of landmark and the amount of breast density. For dense breasts (> or = 40%), the affine and fluid methods outperformed FFD. For breasts with lower density, the affine registration surpassed both fluid and FFD. Mean accuracy (mm) of the affine registration varied between 3.16 (95% CI 2.56, 3.90) for nipple points in breasts with density 20%-39% and 5.73 (4.80, 6.84) for tumor points in breasts with density < 20%. CONCLUSIONS: Affine registration accuracy was comparable to that between independent film readers. More advanced two-dimensional nonrigid registration algorithms were incapable of increasing the accuracy of image alignment when compared to affine registration.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Mamografia/métodos , Radiologia/métodos , Adulto , Algoritmos , Automação , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Modelos Teóricos , Variações Dependentes do Observador
13.
Med J Aust ; 193(5): 277-80, 2010 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-20819046

RESUMO

OBJECTIVE: To investigate the specific factors that graduates perceive to influence their success in obtaining primary training in a chosen field. DESIGN, SETTING AND PARTICIPANTS: The New South Wales Medical Registration Board provided data on doctors who were registered to practise between 1995 and 2006. A brief, paper-based survey was sent to a random selection of 2000 doctors. MAIN OUTCOME MEASURES: Doctors' self-reported perceptions on the impact of demographic details, specialty training applied for, university training and other factors on opportunities for further training after medical school. RESULTS: Of the 375/1915 doctors (19.6%) who responded, most had completed a 6-year undergraduate degree from the University of Sydney, University of NSW or University of Newcastle, and most were at registrar level. Of 242/321 doctors (76%) who had applied for a training position, 240 (99%) had been accepted. The support of a mentor was considered the most positive influence on meeting long-term career goals (255/318 [80%]). Learning how to communicate with patients was valued as the most helpful aspect of medical school (270/318 [85%]). CONCLUSION: The personal attributes of graduates were considered more influential in achieving career goals and accessing further training than perceived features of a medical program. This suggests that more emphasis and research should be devoted to selecting the most appropriate candidates, rather than restructuring medical curricula to meet a presumed need for more content knowledge before graduation.


Assuntos
Atitude do Pessoal de Saúde , Escolha da Profissão , Educação de Graduação em Medicina , Internato e Residência , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , New South Wales , Fatores Sexuais , Inquéritos e Questionários
14.
Mol Cell Neurosci ; 24(3): 646-55, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14664815

RESUMO

BACE1 is a key enzyme in the generation of Abeta, the major component of senile plaques in the brains of Alzheimer's disease patients. We have generated transgenic mice expressing human BACE1 with the Cam Kinase II promoter driving neuronal-specific expression. The transgene contains the full-length coding sequence of human BACE1 preceding an internal ribosome entry site element followed by a LacZ reporter gene. These animals exhibit a bold, exploratory behavior and show elevated 5-hydroxytryptamine turnover. We have also generated a knockout mouse in which LacZ replaces the first exon of murine BACE1. Interestingly these animals show a contrasting behavior, being timid and less exploratory. Despite these clear differences both mouse lines are viable and fertile with no changes in morbidity. These results suggest an unexpected role for BACE1 in neurotransmission, perhaps through changes in amyloid precursor protein processing and Abeta levels.


Assuntos
Ácido Aspártico Endopeptidases/deficiência , Comportamento Animal/fisiologia , Encéfalo/enzimologia , Serotonina/metabolismo , Doença de Alzheimer/enzimologia , Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Secretases da Proteína Precursora do Amiloide , Peptídeos beta-Amiloides/biossíntese , Animais , Ácido Aspártico Endopeptidases/genética , Encéfalo/fisiopatologia , Células Cultivadas , Modelos Animais de Doenças , Endopeptidases , Comportamento Exploratório/fisiologia , Medo/fisiologia , Genes Reporter/genética , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Fenótipo , Transmissão Sináptica/genética , Transgenes/genética
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