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1.
Nature ; 607(7918): 301-306, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35831604

RESUMO

Our understanding of the climatic teleconnections that drove ice-age cycles has been limited by a paucity of well-dated tropical records of glaciation that span several glacial-interglacial intervals. Glacial deposits offer discrete snapshots of glacier extent but cannot provide the continuous records required for detailed interhemispheric comparisons. By contrast, lakes located within glaciated catchments can provide continuous archives of upstream glacial activity, but few such records extend beyond the last glacial cycle. Here a piston core from Lake Junín in the uppermost Amazon basin provides the first, to our knowledge, continuous, independently dated archive of tropical glaciation spanning 700,000 years. We find that tropical glaciers tracked changes in global ice volume and followed a clear approximately 100,000-year periodicity. An enhancement in the extent of tropical Andean glaciers relative to global ice volume occurred between 200,000 and 400,000 years ago, during sustained intervals of regionally elevated hydrologic balance that modified the regular approximately 23,000-year pacing of monsoon-driven precipitation. Millennial-scale variations in the extent of tropical Andean glaciers during the last glacial cycle were driven by variations in regional monsoon strength that were linked to temperature perturbations in Greenland ice cores1; these interhemispheric connections may have existed during previous glacial cycles.

2.
Nature ; 593(7857): 51-55, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33828303

RESUMO

The standard model of particle physics describes the vast majority of experiments and observations involving elementary particles. Any deviation from its predictions would be a sign of new, fundamental physics. One long-standing discrepancy concerns the anomalous magnetic moment of the muon, a measure of the magnetic field surrounding that particle. Standard-model predictions1 exhibit disagreement with measurements2 that is tightly scattered around 3.7 standard deviations. Today, theoretical and measurement errors are comparable; however, ongoing and planned experiments aim to reduce the measurement error by a factor of four. Theoretically, the dominant source of error is the leading-order hadronic vacuum polarization (LO-HVP) contribution. For the upcoming measurements, it is essential to evaluate the prediction for this contribution with independent methods and to reduce its uncertainties. The most precise, model-independent determinations so far rely on dispersive techniques, combined with measurements of the cross-section of electron-positron annihilation into hadrons3-6. To eliminate our reliance on these experiments, here we use ab initio quantum chromodynamics (QCD) and quantum electrodynamics simulations to compute the LO-HVP contribution. We reach sufficient precision to discriminate between the measurement of the anomalous magnetic moment of the muon and the predictions of dispersive methods. Our result favours the experimentally measured value over those obtained using the dispersion relation. Moreover, the methods used and developed in this work will enable further increased precision as more powerful computers become available.

3.
Nature ; 539(7627): 69-71, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27808190

RESUMO

Unlike the electroweak sector of the standard model of particle physics, quantum chromodynamics (QCD) is surprisingly symmetric under time reversal. As there is no obvious reason for QCD being so symmetric, this phenomenon poses a theoretical problem, often referred to as the strong CP problem. The most attractive solution for this requires the existence of a new particle, the axion-a promising dark-matter candidate. Here we determine the axion mass using lattice QCD, assuming that these particles are the dominant component of dark matter. The key quantities of the calculation are the equation of state of the Universe and the temperature dependence of the topological susceptibility of QCD, a quantity that is notoriously difficult to calculate, especially in the most relevant high-temperature region (up to several gigaelectronvolts). But by splitting the vacuum into different sectors and re-defining the fermionic determinants, its controlled calculation becomes feasible. Thus, our twofold prediction helps most cosmological calculations to describe the evolution of the early Universe by using the equation of state, and may be decisive for guiding experiments looking for dark-matter axions. In the next couple of years, it should be possible to confirm or rule out post-inflation axions experimentally, depending on whether the axion mass is found to be as predicted here. Alternatively, in a pre-inflation scenario, our calculation determines the universal axionic angle that corresponds to the initial condition of our Universe.

4.
Phys Rev Lett ; 126(23): 232001, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34170171

RESUMO

In this Letter, we introduce a novel scheme for extrapolating the equation of state of QCD to finite chemical potential that features considerably improved convergence properties and allows us to extend its reach to unprecedentedly high baryonic chemical potentials. We present continuum extrapolated lattice results for the new expansion coefficients and show the thermodynamic observables up to µ_{B}/T≤3.5. This novel expansion does not suffer from the shortcomings that characterize the traditional Taylor expansion method, such as difficulties inherent in performing such an expansion with a limited number of coefficients and the poor signal-to-noise ratio that affects Taylor coefficients determined from lattice calculations.

5.
Ultrasound Obstet Gynecol ; 57(6): 979-986, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32304621

RESUMO

OBJECTIVES: To determine if a policy of universal fetal echocardiography (echo) in pregnancies conceived by in-vitro fertilization (IVF) is cost-effective as a screening strategy for congenital heart defects (CHDs) and to examine the cost-effectiveness of various other CHD screening strategies in IVF pregnancies. METHODS: A decision-analysis model was designed from a societal perspective with respect to the obstetric patient, to compare the cost-effectiveness of three screening strategies: (1) anatomic ultrasound (US): selective fetal echo following abnormal cardiac findings on detailed anatomic survey; (2) intracytoplasmic sperm injection (ICSI) only: fetal echo for all pregnancies following IVF with ICSI; (3) all IVF: fetal echo for all IVF pregnancies. The model initiated at conception and had a time horizon of 1 year post-delivery. The sensitivities and specificities for each strategy, the probabilities of major and minor CHDs and all other clinical estimates were derived from the literature. Costs, including imaging, consults, surgeries and caregiver productivity losses, were derived from the literature and Medicare databases, and are expressed in USA dollars ($). Effectiveness was quantified as quality-adjusted life years (QALYs), based on how the strategies would affect the quality of life of the obstetric patient. Secondary effectiveness was quantified as number of cases of CHD and, specifically, cases of major CHD, detected. RESULTS: The average base-case cost of each strategy was as follows: anatomic US, $8119; ICSI only, $8408; and all IVF, $8560. The effectiveness of each strategy was as follows: anatomic US, 1.74487 QALYs; ICSI only, 1.74497 QALYs; and all IVF, 1.74499 QALYs. The ICSI-only strategy had an incremental cost-effectiveness ratio (ICER) of $2 840 494 per additional QALY gained when compared to the anatomic-US strategy, and the all-IVF strategy had an ICER of $5 692 457 per additional QALY when compared with the ICSI-only strategy. Both ICERs exceeded considerably the standard willingness-to-pay threshold of $50 000-$100 000 per QALY. In a secondary analysis, the ICSI-only strategy had an ICER of $527 562 per additional case of major CHD detected when compared to the anatomic-US strategy. All IVF had an ICER of $790 510 per case of major CHD detected when compared with ICSI only. It was determined that it would cost society five times more to detect one additional major CHD through intensive screening of all IVF pregnancies than it would cost to pay for the neonate's first year of care. CONCLUSION: The most cost-effective method of screening for CHDs in pregnancies following IVF, either with or without ICSI, is to perform a fetal echo only when abnormal cardiac findings are noted on the detailed anatomy scan. Performing routine fetal echo for all IVF pregnancies is not cost-effective. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Fertilização in vitro , Cardiopatias Congênitas/diagnóstico por imagem , Injeções de Esperma Intracitoplásmicas , Análise Custo-Benefício , Árvores de Decisões , Ecocardiografia/economia , Feminino , Cardiopatias Congênitas/economia , Humanos , Gravidez , Qualidade de Vida , Ultrassonografia Pré-Natal/economia , Estados Unidos
6.
J Neurooncol ; 131(2): 277-281, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27757722

RESUMO

Post-radiation leukoencephalopathy is characterized by cognitive impairment and white matter alternations on imaging. Cerebral small vessel disease (SVD) is one of several suggested etiologies. Cerebral microinfarction (CMI) is a recently described marker of SVD. We sought to examine the rate of CMI as a biomarker of ongoing ischemia among patients who underwent brain radiotherapy (RT). 110 patients treated with RT for primary or metastatic brain tumors were enrolled. A total of 685 brain MRI tests performed 1-108 months post-radiation were examined. The annual incidence of CMI was calculated. Only 2 definite CMI were found (2/685, 0.3 %). The calculated annual incidence of CMI was 0.11. This incidence is similar to the normal population, and lower than the reported incidence in patients with intracerebral hemorrhage or cognitive impairment. CMI incidence in patients treated with brain RT is similar to the general population. This finding suggests that post-radiation leukoencephalopathy and cognitive impairment are not due to active SVD solely but rather secondary to other causes such as inflammation, metabolic or direct cell damage.


Assuntos
Neoplasias Encefálicas/radioterapia , Infarto Cerebral/complicações , Doenças de Pequenos Vasos Cerebrais/complicações , Leucoencefalopatias/etiologia , Lesões por Radiação/complicações , Radioterapia/efeitos adversos , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/diagnóstico por imagem , Infarto Cerebral/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Leucoencefalopatias/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/diagnóstico por imagem , Estudos Retrospectivos
7.
Phys Rev Lett ; 116(17): 172001, 2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-27176514

RESUMO

We present a QCD calculation of the u, d, and s scalar quark contents of nucleons based on 47 lattice ensembles with N_{f}=2+1 dynamical sea quarks, 5 lattice spacings down to 0.054 fm, lattice sizes up to 6 fm, and pion masses down to 120 MeV. Using the Feynman-Hellmann theorem, we obtain f_{ud}^{N}=0.0405(40)(35) and f_{s}^{N}=0.113(45)(40), which translates into σ_{πN}=38(3)(3) MeV, σ_{sN}=105(41)(37) MeV, and y_{N}=0.20(8)(8) for the sigma terms and the related ratio, where the first errors are statistical and the second errors are systematic. Using isospin relations, we also compute the individual up and down quark contents of the proton and neutron (results in the main text).

8.
J Surg Res ; 202(2): 428-35, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-27229119

RESUMO

BACKGROUND: In gastric adenocarcinoma, the disparity in lymph node involvement between different age groups has not been thoroughly investigated. The objective of our study was to compare age-associated differences in adequate lymph node harvest and nodal involvement in gastric adenocarcinoma patients. METHODS: We analyzed data extracted from the Surveillance, Epidemiology and End Results database on 13,165 patients diagnosed with stage I-III gastric adenocarcinoma between 2004 and 2011. All patients underwent surgical resection. Statistical comparisons between various age groups were done using the chi-square test and Cox regression. RESULTS: Among 13,165 gastrectomy patients, proportion of patients that had >15 lymph nodes examined decreases significantly with increasing age (P < 0.0001). When adequately staged, older patients had a significantly lower proportion of node-positive tumors (P < 0.0001). Adequate nodal staging was also associated with improved 5-y disease-specific survival across all age groups. CONCLUSIONS: In gastric adenocarcinoma, older patients are less likely to be adequately staged. However, when adequately staged, they are less likely to have node-positive tumors. Adherence to national guidelines, regardless of age, is associated with improved survival outcomes and may alter multimodality management of gastric cancer in the elderly.


Assuntos
Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Gastrectomia , Excisão de Linfonodo , Linfonodos/patologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Adenocarcinoma/cirurgia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Linfonodos/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Programa de SEER , Neoplasias Gástricas/cirurgia , Análise de Sobrevida
9.
Phys Rev Lett ; 113(5): 052301, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25126910

RESUMO

Recent results for moments of multiplicity distributions of net protons and net-electric charge from the STAR Collaboration are compared to lattice QCD results for higher order fluctuations of baryon number and electric charge by the Wuppertal-Budapest Collaboration, with the purpose of extracting the freeze-out temperature and chemical potential. All lattice simulations are performed for a system of 2+1 dynamical quark flavors, at the physical mass for light and strange quarks; all results are continuum extrapolated. We show that it is possible to extract an upper value for the freeze-out temperature, as well as precise baryochemical potential values corresponding to the four highest collision energies of the experimental beam energy scan. Consistency between the freeze-out parameters obtained from baryon number and electric charge fluctuations is found. The freeze-out chemical potentials are now in agreement with the statistical hadronization model.

10.
Genes Immun ; 14(5): 310-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23615072

RESUMO

The Ashkenazi Jewish population has a several-fold higher prevalence of Crohn's disease (CD) compared with non-Jewish European ancestry populations and has a unique genetic history. Haplotype association is critical to CD etiology in this population, most notably at NOD2, in which three causal, uncommon and conditionally independent NOD2 variants reside on a shared background haplotype. We present an analysis of extended haplotypes that showed significantly greater association to CD in the Ashkenazi Jewish population compared with a non-Jewish population (145 haplotypes and no haplotypes with P-value <10(-3), respectively). Two haplotype regions, one each on chromosomes 16 and 21, conferred increased disease risk within established CD loci. We performed exome sequencing of 55 Ashkenazi Jewish individuals and follow-up genotyping focused on variants in these two regions. We observed Ashkenazi Jewish-specific nominal association at R755C in TRPM2 on chromosome 21. Within the chromosome 16 region, R642S of HEATR3 and rs9922362 of BRD7 showed genome-wide significance. Expression studies of HEATR3 demonstrated a positive role in NOD2-mediated NF-κB signaling. The BRD7 signal showed conditional dependence with only the downstream rare CD-causal variants in NOD2, but not with the background haplotype; this elaborates NOD2 as a key illustration of synthetic association.


Assuntos
Doença de Crohn/genética , Judeus/genética , Mutação de Sentido Incorreto , NF-kappa B/genética , Proteínas/genética , Transdução de Sinais/genética , Proteínas Cromossômicas não Histona/genética , Cromossomos Humanos Par 16/genética , Éxons/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Genótipo , Células HEK293 , Haplótipos , Humanos , Modelos Logísticos , Proteína Adaptadora de Sinalização NOD2/genética , Polimorfismo de Nucleotídeo Único , Interferência de RNA , Análise de Sequência de DNA
11.
Br J Cancer ; 109(4): 915-9, 2013 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-23900219

RESUMO

BACKGROUND: This study evaluated the addition of sorafenib to gemcitabine and cisplatin in biliary adenocarcinoma first-line therapy. METHODS: Patients with advanced biliary adenocarcinomas received gemcitabine 1000 mg m(-2) and cisplatin 25 mg m(-2) on a 2 weeks on/1 week off cycle and sorafenib 400 mg twice daily. After the initial 16 patients were enrolled, the chemotherapy doses were amended in view of grade 3 and 4 hand-foot skin reaction and haematologic toxicity. Subsequently, 21 patients received gemcitabine 800 mg m(-2), cisplatin 20 mg m(-2) and sorafenib 400 mg. The primary end point was an improvement in 6-month progression-free survival (PFS6) from historical 57-77% (90% power, type I error of 10%). Pretreatment pERK, evaluated by immunostaining, was correlated with clinical outcome. RESULTS: A total of 39 patients were accrued. The most common grade 3-4 toxicities noted in >10% of patients were fatigue, elevated liver function tests and haematologic toxicities including thromboemboli, hyponatraemia and hypophosphataemia. Six-month progression-free survival was 51% (95% confidence interval (CI) 34-66%). Median PFS and overall survival were 6.5 (95% CI: 3.5-8.3) and 14.4 months (95% CI: 11.6-19.2 months), respectively. No correlation was observed between pERK and outcomes. CONCLUSION: The addition of sorafenib to gemcitabine and cisplatin in biliary adenocarcinomas did not improve efficacy over historical data, and toxicity was increased.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Sistema Biliar/tratamento farmacológico , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Extra-Hepáticos/patologia , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias do Sistema Biliar/patologia , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/patologia , Cisplatino/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Feminino , Neoplasias da Vesícula Biliar/tratamento farmacológico , Neoplasias da Vesícula Biliar/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Niacinamida/administração & dosagem , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Sorafenibe , Resultado do Tratamento , Gencitabina
12.
Phys Rev Lett ; 111(6): 062005, 2013 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-23971565

RESUMO

We present our results for ratios of higher order fluctuations of electric charge as functions of the temperature. These results are obtained in a system of 2+1 quark flavors at physical quark masses and continuum extrapolated. We compare them to preliminary data on higher order moments of the net electric charge distribution from the STAR collaboration. This allows us to determine the freeze-out temperature and chemical potential from first principles. We also show continuum-extrapolated results for ratios of higher order fluctuations of baryon number. These will allow us to test the consistency of the approach, by comparing them to the corresponding experimental data (once they become available) and thus, extracting the freeze-out parameters in an independent way.

13.
Phys Rev Lett ; 111(25): 252001, 2013 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-24483739

RESUMO

While electromagnetic and up-down quark mass difference effects on octet baryon masses are very small, they have important consequences. The stability of the hydrogen atom against beta decay is a prominent example. Here, we include these effects by adding them to valence quarks in a lattice QCD calculation based on Nf=2+1 simulations with five lattice spacings down to 0.054 fm, lattice sizes up to 6 fm, and average up-down quark masses all the way down to their physical value. This allows us to gain control over all systematic errors, except for the one associated with neglecting electromagnetism in the sea. We compute the octet baryon isomultiplet mass splittings, as well as the individual contributions from electromagnetism and the up-down quark mass difference. Our results for the total splittings are in good agreement with experiment.

14.
J Neurooncol ; 114(2): 229-35, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23756727

RESUMO

Leptomeningeal disease (LMD) occurs in 5 % of breast cancer patients. The aim of this study was to identify risk factors related to survival and time to development of LMD in breast cancer patients. A retrospective analysis of breast cancer patients with LMD, evaluated in MDACC between 1995 and 2011. 103 patients with diagnosis of breast cancer and LMD were identified (one male). The median age at LMD diagnosis was 49.2 years. 78.2 % had invasive ductal carcinoma. Hormone receptors (HRs) were positive in 55.3 % of patients, 47.4 % were human epidermal growth factor receptor 2-positive and 22.8 % were triple negative. 52 % of the patients were treated with WBRT, 19 % with spinal radiation, 36 % with systemic chemotherapy and 55 % with intrathecal chemotherapy. Estimated median overall survival from time of breast cancer diagnosis was 3.66 years. Median survival from time of LMD diagnosis was 4.2 months. Time from breast cancer diagnosis to LMD was 2.48 years. In multivariate analysis, HR status and stage at diagnosis were significantly associated with time to LMD diagnosis (p < 0.05). In triple negative patients, time to LMD was shorter. In patients who were HR positive, time to LMD was longer. Survival from LMD diagnosis was significantly associated with both treatment, as well as positive HR status (multivariate analysis p < 0.05). In conclusion LMD has dismal prognosis in breast cancer patients. HR status contributes to time to LMD diagnosis and survival from LMD diagnosis. The impact of treatment aimed at LMD cannot be ascertained in our retrospective study due to the inherent bias associated with the decision to treat.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinomatose Meníngea/secundário , Adulto , Idoso , Neoplasias da Mama/terapia , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Carcinomatose Meníngea/diagnóstico , Carcinomatose Meníngea/metabolismo , Carcinomatose Meníngea/terapia , Pessoa de Meia-Idade , Análise Multivariada , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estudos Retrospectivos , Fatores de Tempo
16.
Nature ; 443(7112): 675-8, 2006 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-17035999

RESUMO

Quantum chromodynamics (QCD) is the theory of the strong interaction, explaining (for example) the binding of three almost massless quarks into a much heavier proton or neutron--and thus most of the mass of the visible Universe. The standard model of particle physics predicts a QCD-related transition that is relevant for the evolution of the early Universe. At low temperatures, the dominant degrees of freedom are colourless bound states of hadrons (such as protons and pions). However, QCD is asymptotically free, meaning that at high energies or temperatures the interaction gets weaker and weaker, causing hadrons to break up. This behaviour underlies the predicted cosmological transition between the low-temperature hadronic phase and a high-temperature quark-gluon plasma phase (for simplicity, we use the word 'phase' to characterize regions with different dominant degrees of freedom). Despite enormous theoretical effort, the nature of this finite-temperature QCD transition (that is, first-order, second-order or analytic crossover) remains ambiguous. Here we determine the nature of the QCD transition using computationally demanding lattice calculations for physical quark masses. Susceptibilities are extrapolated to vanishing lattice spacing for three physical volumes, the smallest and largest of which differ by a factor of five. This ensures that a true transition should result in a dramatic increase of the susceptibilities. No such behaviour is observed: our finite-size scaling analysis shows that the finite-temperature QCD transition in the hot early Universe was not a real phase transition, but an analytic crossover (involving a rapid change, as opposed to a jump, as the temperature varied). As such, it will be difficult to find experimental evidence of this transition from astronomical observations.

17.
J Acoust Soc Am ; 132(3): EL169-75, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22979828

RESUMO

Simultaneous long-term monitoring of underwater sound and ship traffic provided an opportunity to study how low-frequency noise correlated with ocean-based commercial shipping trends. Between 2007 and 2010 changes in regional shipping off southern California occurred as a consequence of economic and regulatory events. Underwater average noise levels measured before and during these events showed a net reduction of 12 dB. Statistical models revealed that a reduction of 1 ship transit per day resulted in 1 dB decrease in average noise. This synthesis of maritime traffic statistics with ocean noise monitoring provides an important step in understanding the magnitude and potential effects of chronic noise in marine habitats.


Assuntos
Recessão Econômica , Ruído dos Transportes/prevenção & controle , Navios/economia , Recessão Econômica/tendências , Ecossistema , Monitoramento Ambiental/métodos , Análise de Fourier , Modelos Estatísticos , Movimento (Física) , Ruído dos Transportes/economia , Ruído dos Transportes/estatística & dados numéricos , Oceanos e Mares , Navios/legislação & jurisprudência , Navios/estatística & dados numéricos , Som , Espectrografia do Som , Fatores de Tempo , Água
18.
J Fish Biol ; 80(5): 1380-400, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22497389

RESUMO

The detailed movements of 32 acoustically tagged broadnose sevengill shark Notorynchus cepedianus were documented in and around north-east Pacific Ocean estuarine embayments from 2005 to 2007. Arrangements of passive acoustic receivers allowed analysis of movement at several spatial scales, with sex and size examined as possible factors influencing the pattern and timing of these movements. Notorynchus cepedianus exhibited a distinctly seasonal pattern of estuary use over three consecutive years, entering Willapa Bay in the spring, residing therein for extended periods of time during the summer and dispersing into nearshore coastal habitats and over the continental shelf during the autumn. Notorynchus cepedianus within Willapa Bay showed spatio-temporal patterns of segregation by size and sex, with males and small females using peripheral southern estuary channels early in the season before joining large females, who remained concentrated in central estuary channels for the entire season. Individuals displayed a high degree of fidelity not only to Willapa Bay (63% were documented returning over three consecutive seasons), but also to specific areas within the estuary, showing consistent patterns of site use from year to year. Cross-estuary movement was common during the summer, with most fish also moving into an adjacent estuarine embayment for some extent of time. Most winter and autumn coastal detections of N. cepedianus were made over the continental shelf near Oregon and Washington, U.S.A., but there were also examples of individuals moving into nearshore coastal habitats further south into California, suggesting the feasibility of broad-scale coastal movements to known birthing and nursery grounds for the species. These findings contribute to a better understanding of N. cepedianus movement ecology, which can be used to improve the holistic management of this highly mobile apex predator in regional ecosystems.


Assuntos
Migração Animal , Tubarões/fisiologia , Acústica , Sistemas de Identificação Animal , Animais , Baías , California , Ecologia/métodos , Ecossistema , Feminino , Masculino , Oregon , Oceano Pacífico , Estações do Ano , Washington
19.
Int J Pediatr Otorhinolaryngol ; 147: 110803, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34198156

RESUMO

BACKGROUND: Diagnostic polysomnography (PSG) is recommended prior to adenotonsillectomy (AT) for children with obstructive sleep apnea (OSA) and certain high-risk characteristics, but resource limitations often prevent this practice. OBJECTIVE: We performed a population-based assessment of children across Ontario, Canada to describe and quantify disparities in PSG. METHODS AND MATERIALS: This retrospective cohort study was performed using provincial health administrative data held at ICES. We identified children 0-10 years old who underwent PSG and AT between 2009 and 2018, and those with a PSG within 18 months prior to and/or 12 months following AT. We calculated the odds of PSG prior to/following AT after adjustment for demographics, medical comorbidities, geographic and socioeconomic characteristics. Our main predictor was driving time/distance to the nearest pediatric sleep centre ascertained using spatial analysis and geographic information systems. RESULTS: We identified 27,837 children <10 years old who underwent AT for OSA in Ontario. Only 12.8% had a PSG within 18 months prior and 5.7% had a PSG within 12 months following AT. Shorter driving time/distance, older age, male sex and certain comorbidities were associated with increased odds of PSG. CONCLUSION: Only a small proportion of children in our cohort underwent PSG prior to or following AT surgery despite universal access to healthcare. This study suggests a need to increase overall PSG access, particularly for those living distant from existing pediatric sleep centres. Future studies could determine if increased PSG testing in 'underserviced areas' would reduce overall surgery rates and/or improve health outcomes.


Assuntos
Apneia Obstrutiva do Sono , Idoso , Canadá , Criança , Pré-Escolar , Acessibilidade aos Serviços de Saúde , Humanos , Lactente , Recém-Nascido , Masculino , Polissonografia , Estudos Retrospectivos , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologia
20.
Trials ; 22(1): 186, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33673867

RESUMO

BACKGROUND: Depression and anxiety impact up to 1 in 5 pregnant and postpartum women worldwide. Yet, as few as 20% of these women are treated with frontline interventions such as evidence-based psychological treatments. Major barriers to uptake are the limited number of specialized mental health treatment providers in most settings, and problems with accessing in-person care, such as childcare or transportation. Task sharing of treatment to non-specialist providers with delivery on telemedicine platforms could address such barriers. However, the equivalence of these strategies to specialist and in-person models remains unproven. METHODS: This study protocol outlines the Scaling Up Maternal Mental healthcare by Increasing access to Treatment (SUMMIT) randomized trial. SUMMIT is a pragmatic, non-inferiority test of the comparable effectiveness of two types of providers (specialist vs. non-specialist) and delivery modes (telemedicine vs. in-person) of a brief, behavioral activation (BA) treatment for perinatal depressive and anxiety symptoms. Specialists (psychologists, psychiatrists, and social workers with ≥ 5 years of therapy experience) and non-specialists (nurses and midwives with no formal training in mental health care) were trained in the BA protocol, with the latter supervised by a BA expert during treatment delivery. Consenting pregnant and postpartum women with Edinburgh Postnatal Depression Scale (EPDS) score of ≥ 10 (N = 1368) will be randomized to one of four arms (telemedicine specialist, telemedicine non-specialist, in-person specialist, in-person non-specialist), stratified by pregnancy status (antenatal/postnatal) and study site. The primary outcome is participant-reported depressive symptoms (EPDS) at 3 months post-randomization. Secondary outcomes are maternal symptoms of anxiety and trauma symptoms, perceived social support, activation levels and quality of life at 3-, 6-, and 12-month post-randomization, and depressive symptoms at 6- and 12-month post-randomization. Primary analyses are per-protocol and intent-to-treat. The study has successfully continued despite the COVID-19 pandemic, with needed adaptations, including temporary suspension of the in-person arms and ongoing randomization to telemedicine arms. DISCUSSION: The SUMMIT trial is expected to generate evidence on the non-inferiority of BA delivered by a non-specialist provider compared to specialist and telemedicine compared to in-person. If confirmed, results could pave the way to a dramatic increase in access to treatment for perinatal depression and anxiety. TRIAL REGISTRATION: ClinicalTrials.gov NCT04153864 . Registered on November 6, 2019.


Assuntos
Ansiedade/terapia , Depressão Pós-Parto/terapia , Depressão/terapia , Acessibilidade aos Serviços de Saúde , Complicações na Gravidez/terapia , Psicoterapia/métodos , Telemedicina/métodos , COVID-19 , Atenção à Saúde/métodos , Estudos de Equivalência como Asunto , Feminino , Humanos , Serviços de Saúde Materna , Serviços de Saúde Mental/organização & administração , Tocologia , Enfermeiras e Enfermeiros , Ensaios Clínicos Pragmáticos como Assunto , Gravidez , Escalas de Graduação Psiquiátrica , Psiquiatria , Psicologia , SARS-CoV-2 , Assistentes Sociais , Especialização
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