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1.
Nat Commun ; 15(1): 4251, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762487

RESUMO

Sea level rise (SLR) affects coastal flood regimes and poses serious challenges to flood risk management, particularly on ungauged coasts. To address the challenge of monitoring SLR at local scales, we propose a high tide flood (HTF) thresholding system that leverages machine learning (ML) techniques to estimate SLR and HTF thresholds at a relatively fine spatial resolution (10 km) along the United States' coastlines. The proposed system, complementing conventional linear- and point-based estimations of HTF thresholds and SLR rates, can estimate these values at ungauged stretches of the coast. Trained and validated against National Oceanic and Atmospheric Administration (NOAA) gauge data, our system demonstrates promising skills with an average Kling-Gupta Efficiency (KGE) of 0.77. The results can raise community awareness about SLR impacts by documenting the chronic signal of HTF and providing useful information for adaptation planning. The findings encourage further application of ML in achieving spatially distributed thresholds.

2.
Surg Obes Relat Dis ; 18(7): 943-947, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35595651

RESUMO

BACKGROUND: Bariatric surgery has demonstrated sustained improvements in quality. Malpractice closed claims have been offered as a means of assessing quality. Few studies have investigated malpractice closed claims and opportunities for improvement in bariatric surgery. OBJECTIVES: To examine the prevalence and causes of malpractice claims with examination of prospects for quality improvement. SETTING: University hospital, United States; private practice. METHODS: Four national malpractice insurers participated in the closed-claims registry. Data regarding patients, staff, procedures, and hospital status were gathered from closed-claims files. Following data collection, a clinical summary of each closed claim was collected and later assessed by an expert panel on the basis of the following: contributing diagnosis and treatment events; whether complications were potentially preventable by the surgeon; the role of language, fatigue, distraction, workload, or teaching hospital/trainee supervision; communication concerns; and final care determination. RESULTS: A total of 175 closed claims were collected from index bariatric surgeries within the period from 2006-2014. Of these, 75.9% of surgeons were board certified and 43.3% of the hospitals were accredited for bariatric surgery. Most clinical complications after bariatric surgery that led to malpractice lawsuits were mortality (35.1%) and leaks (17.5%). While they were not the common cause for malpractice suits, bleeding (5.3%), retained foreign body (5.3%), and vascular injury (4.4%) occurred at higher rates than national averages. CONCLUSION: Prevalence of malpractice claims regarding bariatric surgery is low. Failure to diagnose, delay in treatment, postoperative care, and communication domain responses indicate future opportunities for improvement.


Assuntos
Cirurgia Bariátrica , Imperícia , Cirurgia Bariátrica/efeitos adversos , Humanos , Prevalência , Sistema de Registros , Estados Unidos/epidemiologia
3.
J Infrastruct Syst ; 27(4)2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36118678

RESUMO

High tide flooding (HTF) already affects traffic in many US coastal areas, but the issue will worsen significantly in the future. While studies show that large storm surge events threaten to be ever more costly, less damaging, but more frequent HTF events remain understudied and potentially carry a comparable economic impact. This study advances our understanding of the risks and impacts of HTF on vulnerable traffic corridors using hourly tide gauge water levels, sea-level rise projections, and link-level spatial analysis. It is the first study to estimate HTF economic impacts for varying levels of intervention, including reasonably anticipated driver-initiated rerouting and ancillary protection of adjacent property. The 2020 annual national-level costs of $1.3 to $1.5 billion will increase to $28 to $37 billion in 2050 and $220 to $260 billion in 2100 for medium to high greenhouse gas (GHG) emissions scenarios, respectively. Total costs over the century are $1.0 to $1.3 trillion (discounted 3%). Additional cost-effective protection by building sea walls or raising road surfaces could significantly reduce 2100 costs to $61 to $78 billion, but there remain many barriers to adopting least-cost adaptation decisions, and these gains may only be realized with careful planning and information sharing.

4.
Rev Geophys ; 58(3): e2019RG000672, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32879921

RESUMO

Global sea level provides an important indicator of the state of the warming climate, but changes in regional sea level are most relevant for coastal communities around the world. With improvements to the sea-level observing system, the knowledge of regional sea-level change has advanced dramatically in recent years. Satellite measurements coupled with in situ observations have allowed for comprehensive study and improved understanding of the diverse set of drivers that lead to variations in sea level in space and time. Despite the advances, gaps in the understanding of contemporary sea-level change remain and inhibit the ability to predict how the relevant processes may lead to future change. These gaps arise in part due to the complexity of the linkages between the drivers of sea-level change. Here we review the individual processes which lead to sea-level change and then describe how they combine and vary regionally. The intent of the paper is to provide an overview of the current state of understanding of the processes that cause regional sea-level change and to identify and discuss limitations and uncertainty in our understanding of these processes. Areas where the lack of understanding or gaps in knowledge inhibit the ability to provide the needed information for comprehensive planning efforts are of particular focus. Finally, a goal of this paper is to highlight the role of the expanded sea-level observation network-particularly as related to satellite observations-in the improved scientific understanding of the contributors to regional sea-level change.

5.
Sci Data ; 6(1): 326, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852894

RESUMO

We develop an aggregated extreme sea level (ESL) indicator for the contiguous United States coastline, which is comprised of separate indicators for mean sea level (MSL) and storm surge climatology (SSC). We use water level data from tide gauges to estimate interannual to multi-decadal variability of MSL and SSC and identify coastline stretches where the observed changes are coherent. Both the MSL and SSC indicators show significant fluctuations. Indicators of the individual components are combined with multi-year tidal contributions into aggregated ESL indicators. The relative contribution of the different components varies considerably in time and space. Our results highlight the important role of interannual to multi-decadal variability in different sea level components in exacerbating, or reducing, the impacts of long-term MSL rise over time scales relevant for coastal planning and management. Regularly updating the proposed indicator will allow tracking changes in ESL posing a threat to many coastal communities, including the identification of periods where the likelihood of flooding is particularly large or small.

6.
Earths Future ; 7(12): 1235-1269, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32064296

RESUMO

Sea-level rise sits at the frontier of usable climate climate change research, because it involves natural and human systems with long lags, irreversible losses, and deep uncertainty. For example, many of the measures to adapt to sea-level rise involve infrastructure and land-use decisions, which can have multigenerational lifetimes and will further influence responses in both natural and human systems. Thus, sea-level science has increasingly grappled with the implications of (1) deep uncertainty in future climate system projections, particularly of human emissions and ice sheet dynamics; (2) the overlay of slow trends and high-frequency variability (e.g., tides and storms) that give rise to many of the most relevant impacts; (3) the effects of changing sea level on the physical exposure and vulnerability of ecological and socioeconomic systems; and (4) the challenges of engaging stakeholder communities with the scientific process in a way that genuinely increases the utility of the science for adaptation decision making. Much fundamental climate system research remains to be done, but many of the most critical issues sit at the intersection of natural sciences, social sciences, engineering, decision science, and political economy. Addressing these issues demands a better understanding of the coupled interactions of mean and extreme sea levels, coastal geomorphology, economics, and migration; decision-first approaches that identify and focus research upon those scientific uncertainties most relevant to concrete adaptation choices; and a political economy that allows usable science to become used science.

7.
Coast Manage ; 47(2): 127-150, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-32665748

RESUMO

Sea-level rise (SLR) is not just a future trend; it is occurring now in most coastal regions across the globe. It thus impacts not only long-range planning in coastal environments, but also emergency preparedness. Its inevitability and irreversibility on long time scales, in addition to its spatial non-uniformity, uncertain magnitude and timing, and capacity to drive non-stationarity in coastal flooding on planning and engineering timescales, create unique challenges for coastal risk-management decision processes. This review assesses past United States federal efforts to synthesize evolving SLR science in support of coastal risk management. In particular, it outlines the: (1) evolution in global SLR scenarios to those using a risk-based perspective that also considers low-probability but high-consequence outcomes, (2) regionalization of the global scenarios, and (3) use of probabilistic approaches. It also describes efforts to further contextualize regional scenarios by combining local mean sea-level changes with extreme water level projections. Finally, it offers perspectives on key issues relevant to the future uptake, interpretation, and application of sea-level change scenarios in decision-making. These perspectives have utility for efforts to craft standards and guidance for preparedness and resilience measures to reduce the risk of coastal flooding and other impacts related to SLR.

8.
Langmuir ; 31(26): 7274-82, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26018196

RESUMO

Real time in situ conductance is collected continuously during atomic layer deposition (ALD) of zinc oxide films, and trends are used to study ALD nucleation on polypropylene, nylon-6, SiO2, TiO2, and Al2O3 substrates. The detailed conductance change during the ALD cycle is ascribed to changes in surface band bending upon precursor/reactant exposure. Conductive pathways form earlier on the inorganic surfaces than on the polymers, with Al2O3 substrates showing more rapid nucleation than SiO2 or TiO2, consistent with the expected density of nucleation sites (e.g., hydroxyl groups) on these different materials. The measured conductance is ohmic, and both two- and four-electrode configurations show the same data trends. Detailed analysis of conductivity at deposition temperatures between 100 and 175 °C shows faster conductivity decay at higher temperature during the water purge step, ascribed to thermally activated water desorption kinetics. Analysis of real-time conductivity during ALD of other material systems could provide further insight into key aspects of film nucleation and nuclei coalescence.

9.
ACS Appl Mater Interfaces ; 6(12): 9280-9, 2014 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-24850237

RESUMO

Patterning is an essential part of many industrial processes from printing to semiconductor manufacturing. In this work, we demonstrate a new method to pattern and selectively coat nonwoven textiles by atomic layer deposition (ALD) using compressive mask patterning. A physical mask combined with mechanical compression allows lateral definition and fidelity of the ALD coating to be controlled. We produce features of several sizes on different nonwoven fiber materials and demonstrate the ability to limit diffusion effects to within <200 µm of the pattern edge. Lateral and vertical penetration of reactive growth species into nonwoven mats is investigated by plan-view and cross-sectional imaging. Vertical growth is also analyzed by imaging coating depth into fiber mat stacks. We develop a fully quantitative transport model that describes well the effect of fiber structure and mechanical compression on the extent of coating under the physical mask. This method could be implemented for high-volume patterning for applications including flexible electronics.

10.
ACS Appl Mater Interfaces ; 5(11): 5253-9, 2013 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-23724894

RESUMO

Low-temperature vapor-phase tungsten atomic layer deposition (ALD) using WF6 and dilute silane (SiH4, 2% in Ar) can yield highly conductive coatings on nylon-6 microfiber mats, producing flexible and supple nonwovens with conductivity of ∼1000 S/cm. We find that an alumina nucleation layer, reactant exposure, and deposition temperature all influence the rate of W mass uptake on 3D fibers, and film growth rate is calibrated using high surface area anodic aluminum oxide. Transmission electron microscopy (TEM) reveals highly conformal tungsten coatings on nylon fibers with complex "winged" cross-section. Using reactant gas "hold" sequences during the ALD process, we conclude that reactant species can transport readily to reactive sites throughout the fiber mat, consistent with conformal uniform coverage observed by TEM. The conductivity of 1000 S/cm for the W-coated nylon is much larger than found in other conductive nonwovens. We also find that the nylon mats maintain 90% of their conductivity after being flexed around cylinders with radii as small as 0.3 cm. Metal ALD coatings on nonwovens make possible the solvent-free functionalization of textiles for electronic applications.


Assuntos
Técnicas Biossensoriais/métodos , Caprolactama/análogos & derivados , Eletrônica Médica/métodos , Nanofibras/química , Polímeros/química , Tungstênio/química , Óxido de Alumínio/química , Caprolactama/química , Condutividade Elétrica , Microscopia Eletrônica de Transmissão , Têxteis
12.
Am J Clin Pathol ; 132(2): 228-36, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19605817

RESUMO

This study specifically addressed the performance of chromogenic in situ hybridization (CISH) on HER2 testing in 66 breast carcinomas with chromosome 17 polysomy and 49 carcinomas with an equivocal HercepTest (DakoCytomation, Carpinteria, CA) score by comparing CISH with corresponding FISH results at 2 test sites and evaluating intersite agreement of CISH results. For tumors with chromosome 17 polysomy, when using the manufacturers' criteria, the concordance values between CISH and FISH at site A, site B, and intersite CISH agreement were 95.8%, 95.5%, and 93.5%, respectively; when using the American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) criteria, the values were 100.0%, 100.0%, and 100.0%, respectively. For tumors with an equivocal HercepTest score, when using the manufacturers' criteria, the concordance values between the 2 methods at site A, site B, and intersite CISH agreement were 88.2%, 95.1%, and 91.1%, respectively; when using the ASCO/CAP criteria, the values were 96.7%, 97.3%, and 97.4%, respectively. These results indicate that CISH is reliable for testing these 2 types of tumors, especially when the ASCO/CAP criteria are used.


Assuntos
Neoplasias da Mama/genética , Cromossomos Humanos Par 17 , Genes erbB-2 , Hibridização In Situ/métodos , Trissomia , Feminino , Técnicas Genéticas/normas , Humanos , Imuno-Histoquímica , Hibridização In Situ/normas , Receptor ErbB-2 , Reprodutibilidade dos Testes
13.
Am J Clin Pathol ; 131(4): 490-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19289584

RESUMO

Chromogenic in situ hybridization (CISH) has shown the potential to replace fluorescence in situ hybridization (FISH) to determine HER2 gene status. To validate the reliability of CISH, we used 226 consecutive breast carcinomas from 2 institutions and tested CISH and FISH on the same tumor set simultaneously at different test sites. Besides manufacturers' scoring criteria, the new American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) guidelines were used to interpret HER2 status. The concordance between CISH and FISH for positive and negative results was 98.5% at site A and 98.6% at site B using the manufacturers' criteria, and 99.0% at site A and 99.1% at site B using the ASCO/CAP criteria. Reproducibility of CISH results was more than 98.0% among 3 sites using the manufacturers' criteria and 100.0% between 2 sites using the ASCO/CAP criteria. Our results confirm that CISH is reliable for HER2 testing per ASCO/CAP guidelines.


Assuntos
Neoplasias da Mama/genética , Genes erbB-2 , Hibridização In Situ/métodos , Compostos Cromogênicos , Feminino , Guias como Assunto , Humanos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
14.
Int J Drug Policy ; 19(1): 52-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18226518

RESUMO

BACKGROUND: There is strong evidence that harm reduction interventions such as Supervised Injection Sites and Needle Exchange Programs prevent many of the negative consequences of problematic substance use. Yet many governments, including the United States and Canada, still do not endorse these interventions, claiming that they do not get people off of drugs and send a mixed message. METHODS: This paper will analyze objections to harm reduction in light of the ethical theories of John Stuart Mill, Immanuel Kant and Aristotle. RESULTS: The most important ethical issue in the abstinence vs. harm reduction debate is whether harm reduction - because it does not require individuals to either reduce their consumption of illicit substances or to abstain from illicit substance use - can be ethically justified. CONCLUSION: Harm reduction interventions are clearly justified on Utilitarian grounds because, based on the evidence, such policies would produce the greatest good for the greatest number. However, Kant would not think that the values guiding harm reduction are ethical because the justification of harm reduction interventions focuses exclusively on examining consequences. Virtue Ethics seeks to find the proper balance between harm reduction and abstinence. We claim that the virtue of compassion would provide a defense of harm reduction.


Assuntos
Teoria Ética , Redução do Dano/ética , Serviços Preventivos de Saúde/ética , Abuso de Substâncias por Via Intravenosa/prevenção & controle , Virtudes , Humanos
15.
Cardiovasc Revasc Med ; 8(1): 28-37, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17293266

RESUMO

PURPOSE: The objective of this study was to determine the effects of different doses of gamma-emitting radioactive stents on intimal hyperplasia in a porcine coronary stent model at 28 days. METHODS: Sixty-four bare stents and those coated with palladium-103 [activities of 0 (control), 0.5, 1.0, 2.0, and 4.0 mCi] were implanted in the coronary arteries of 32 pigs. Stented segments were evaluated by histomorphometry at 28 days. RESULTS: There was significantly more intima in the 0.5- and 1-mCi stents than in controls (4.27+/-0.52 and 4.71+/-1.13 vs. 1.71+/-0.61 mm(2); P<.0001). Neointimal formation in 2-mCi stents was similar to that in controls, while that in 4-mCi stents was reduced compared to that in controls (2.34+/-1.61 and 0.82+/-0.25 vs. 1.71+/-0.61 mm(2); P=NS and P<.05, respectively). Stent margin neointimal response was representative of that within the stent body, with nonsignficant modest increases in intimal area at adjacent nonstented segments in radioactive stent groups. There was a dose-dependent increase in inflammation scores. Radioactive stents had lower intimal smooth muscle and higher fibrin scores. There was an increase in adventitial fibrosis in 1- and 2-mCi stents versus controls (1.26+/-0.99, and 2.25+/-1.27 vs. 0.21+/-0.31; P<.001). CONCLUSION: Dose-response inhibition of in-stent hyperplasia with minimal "edge effects" occurs with low-energy gamma-emitting stents. An increased inflammatory response at higher doses in palladium-103 stents indicates that later follow-up studies are necessary.


Assuntos
Braquiterapia , Reestenose Coronária/prevenção & controle , Vasos Coronários/patologia , Vasos Coronários/efeitos da radiação , Stents , Túnica Íntima/patologia , Túnica Íntima/efeitos da radiação , Animais , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Raios gama , Hiperplasia/radioterapia , Paládio/uso terapêutico , Radioisótopos/uso terapêutico , Sus scrofa , Resultado do Tratamento
16.
Obes Surg ; 16(6): 721-7, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16756731

RESUMO

BACKGROUND: Laparoscopic bariatric surgery has experienced a rapid expansion of interest over the past 5 years, with a 470% increase. This rapid expansion has markedly increased overall cost, reducing surgical access. Many surgeons believe that the traditional open approach is a cheaper, safer, equally effective alternative. METHODS: 16 highly experienced "open" bariatric surgeons with a combined total of 25,759 cases representing >200 surgeon years of experience, pooled their open Roux-en-Y gastric bypass (ORYGBP) data, and compared their results to the leading laparoscopic (LRYGBP) papers in the literature. RESULTS: In the overall series, the incisional hernia rate was 6.4% using the standard midline incision. Utilizing the left subcostal incision (LSI), it was only 0.3%. Return to surgery in <30 days was 0.7%, deaths 0.25%, and leaks 0.4%. Average length of stay was 3.4 days, and return to usual activity 21 days. Small bowel obstruction was significantly higher with the LRYGBP. Surgical equipment costs averaged approximately $3,000 less for "open" cases. LRYGBP had an added expense for longer operative time. This more than made up for the shorter length of stay with the laparoscopic approach. CONCLUSIONS: The higher cost, higher leak rate, higher rate of small bowel obstruction, and similar long-term weight loss results make the "open" RYGBP our preferred operation. If the incision is taken out of the equation (i.e. use of the LSI), the significant advantages of the open technique become even more obvious.


Assuntos
Derivação Gástrica/métodos , Laparoscopia , Feminino , Derivação Gástrica/efeitos adversos , Derivação Gástrica/economia , Hérnia Abdominal/epidemiologia , Humanos , Obstrução Intestinal/epidemiologia , Laparoscopia/efeitos adversos , Laparoscopia/economia , Tempo de Internação , Masculino , Complicações Pós-Operatórias/epidemiologia , Resultado do Tratamento
17.
Int J Radiat Oncol Biol Phys ; 54(2): 551-61, 2002 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-12243835

RESUMO

PURPOSE: To determine the long-term dose response of novel low-dose gamma-emitting stents in a rabbit iliac artery model. METHODS AND MATERIALS: Control stents (n=24) and 103Pd stents 1.0 to 4.0 mCi (n=36) were implanted in the iliac arteries of 30 New Zealand rabbits. Stents were evaluated by intravascular ultrasound (immediately post procedure and before killing) and by histomorphometry. RESULTS: At 26 weeks, 28 rabbits were killed, with no evidence of stent thrombosis. In the body of the stent there was a dose-response relationship with 50% inhibition of intimal hyperplasia at the highest activity compared to control stents (p=0.07) and a significant increase in intimal hyperplasia at the lowest activity (p < 0.01). At the stent edges, there was a significant reduction of lumen area at all activity levels compared to control stents, which was most prominent at the proximal stent edge. Higher-activity stents demonstrated incomplete endothelialization and immature neointimal formation. CONCLUSIONS: Continuous low-dose-rate irradiation by gamma-emitting 103Pd stents is feasible with reduction of in-stent hyperplasia in a dose-related manner. However, significant narrowing at the stent edges, increased in-stent hyperplasia at lower activities, and incomplete vascular healing with persistence of immature neointima at higher activities are significant limitations.


Assuntos
Raios gama/uso terapêutico , Artéria Ilíaca/efeitos da radiação , Paládio/uso terapêutico , Radioisótopos/uso terapêutico , Stents , Túnica Íntima/efeitos da radiação , Animais , Relação Dose-Resposta à Radiação , Hiperplasia/etiologia , Hiperplasia/patologia , Hiperplasia/prevenção & controle , Artéria Ilíaca/patologia , Modelos Animais , Coelhos , Radiobiologia , Recidiva , Stents/efeitos adversos , Túnica Íntima/patologia , Grau de Desobstrução Vascular
18.
Philadelphia; W. B. Saunders; 2 ed; 1988. xvi,798 p. ilus, tab.
Monografia em Inglês | Sec. Munic. Saúde SP, HSPM-Acervo | ID: sms-6632
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