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1.
Waste Manag ; 104: 262-269, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31991267

RESUMO

Anaerobic digestion (AD) reduces GHG emission and facilitates renewable energy generation. The slow rate of adoption of this technology is often attributed to economic and technical considerations. Collaboration of two or more dairy farms into a centralized AD system can improve the process economics through economies of scale. However, uncertainties related to the process parameters and the scope/scale of the collaborative implementation impede its adoption. This study presents techno-economic optimization model as a design aid to determine ideal location, capacity, and participation level (cluster size) that maximize economic return on a cooperative digester. This study employs a probabilistic approach to overcome uncertainty regarding project parameters such as manure biomethane potential (BMP), project capital, and electricity sale price. Two case studies based on dairy production regions in Wisconsin were developed to test the model and demonstrate its capabilities. Herd sizes and spatial distribution in a given region were found to be critical factors in determining the viability of digestion projects in general, and collaborative digestion systems in particular. The number of simulation runs needed to capture the probability of profitable AD facility establishment was less than 1000 for both case studies assessed. Electricity sale price and biomethane potential of feedstock utilized were found to be the most restrictive to the feasibility of AD adoption. Changing the optimization objective function, to adopting maximization, favored the formation of collaborative AD facilities for both case studies evaluated.


Assuntos
Biocombustíveis , Esterco , Anaerobiose , Animais , Metano , Técnicas de Planejamento , Incerteza , Wisconsin
3.
Water Res ; 171: 115403, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31901508

RESUMO

Remote sensing reflectance (Rrs) values measured by satellite sensors involve large amounts of uncertainty leading to non-negligible noise in remote Chlorophyll-a (Chl-a) concentration estimation. This work distinguished between two main stages in the case of estimating distributions of Chl-a within the Gulf of St. Lawrence (Canada). At the model building stage, the retrieval algorithm used both in-situ Chl-a measurements and the corresponding Moderate Resolution Imaging Spectroradiometer (MODIS) L2-level data estimated Rrs at 412, 443, 469, 488, 531, 547, 555, 645, 667, 678 nm at a 1 km spatial resolution during 2004-2013. Through the training and validation of various models and Rrs combinations of the considered eight techniques (including support vector regression, artificial neural networks, gradient boosting machine, random forests, standard CI-OC3M, multiple linear regression, generalized addictive regression, principal component regression), the support vector regression (SVR) technique was shown to have the best performance in Chl-a concentration estimation using Rrs at 412, 443, 488, 531 and 678 nm. The accuracy indicators for both the training (850) and the validation (213) datasets were found to be very good to excellent (e.g., the R2 value varied between 0.7058 and 0.9068). At the space-time estimation stage, this work took a step forward by using the Bayesian maximum entropy (BME) theory to further process the SVR estimated Chl-a concentrations by incorporating the inherent spatiotemporal dependency of physical Chl-a distribution. A 56% improvement was achieved in the reduction of the mean uncertainty of the validation data decreased considerably (from 1.2222 to 0.5322 mg/m3). Then, this novel BME/SVR framework was employed to estimate the daily Chl-a concentrations in the Gulf of St. Lawrence during Jan 1-Dec 31 of 2017 (1 km spatial resolution). The results showed that the daily mean Chl-a concentration varied from 1.6630 to 3.3431 mg/m3, and that the daily mean Chl-a uncertainty reduction of the composite BME/SVR vs. the SVR estimation had a maximum reduction value of 1.0082 and an average reduction value of 0.6173 mg/m3. The monthly spatial Chl-a distribution covariances showed that the highest Chl-a concentration variability occurred during November and that the spatiotemporal Chl-a concentration pattern changed a lot during the period August to November. In conclusion, the proposed BME/SVR was shown to be a promising remote Chl-a retrieval approach that exhibited a significant ability in reducing the non-negligible uncertainty and improving the accuracy of remote sensing Chl-a concentration estimates.


Assuntos
Clorofila A , Tecnologia de Sensoriamento Remoto , Teorema de Bayes , Canadá , Clorofila , Monitoramento Ambiental , Incerteza
5.
Int J Sports Med ; 41(1): 44-53, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31747700

RESUMO

The indirect identification of doping in sports can be performed by assessing athletes' hematological perturbations from the analysis of blood collected on different occasions. Because prosecution for doping based on this information requires expensive and time-consuming interpretation of blood analysis results by various expert hematologists, mathematical data screening is performed to decide which cases should be forwarded to hematologists. The current Bayesian and univariate screening of data does not process the multivariate trends of blood parameters or take the time interval between samplings into account. This work presents a computational tool that overcomes these limitations by calculating a single score, the hematological perturbation index (HPIx), for which a threshold is defined above which hematologists should be asked to assess the athlete's biological passport. The doping detection from this index, normalized for days difference between samplings based on 3, 4 or 5 consecutive samplings, is associated with true positive result rates (TP) not below 98% and false positive result rates (FP) less than 0.9%. Therefore, this tool can be useful as an early warning system of hematological perturbations to decide which athletes should be more closely monitored and which biological passports should be forwarded to hematologists for medical interpretation of data.


Assuntos
Doping nos Esportes , Testes Hematológicos , Detecção do Abuso de Substâncias/métodos , Reações Falso-Positivas , Humanos , Método de Monte Carlo , Análise Multivariada , Incerteza
6.
Waste Manag ; 102: 340-350, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31715554

RESUMO

The excessive expansion of cities and the consequent increase in urban population, especially in recent years, have led to a significant increase in consumptions and generations of different types of municipal solid waste (MSW). In this research, a robust green location-allocation-inventory problem (LAIP) is investigated to design an efficient MSW management system. Since the exact amount of MSW composition in different regions is not known and is uncertain, robust optimization technique is applied to formulate the problem as a mixed-integer linear programming (MILP) model. The objective is to minimize the total cost including fixed locational costs of collection and processing/disposal facilities, operational costs of facilities, transportation costs, penalty costs of non-collected waste and costs arising from pollution emissions. The validation of the proposed model is performed by different problems based on real-life data in deterministic and uncertain conditions using CPLEX solver of GAMS software. Then, the effects of greenness are evaluated by performing a sensitivity analysis on the parameter of pollution cost. Finally, the concept of robustness worthiness threshold (RWT) under budget constraint is introduced and discussed.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Cidades , Resíduos Sólidos , Transportes , Incerteza
8.
BJOG ; 127(3): 364-375, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31507061

RESUMO

OBJECTIVE: Unselected population-based BRCA testing provides the opportunity to apply genomics on a population-scale to maximise primary prevention for breast-and-ovarian cancer. We compare long-term outcomes of population-based and family-history (FH)/clinical-criteria-based BRCA testing on psychological health and quality of life. DESIGN: Randomised controlled trial (RCT) (ISRCTN73338115) GCaPPS, with two-arms: (i) population-screening (PS); (ii) FH/clinical-criteria-based testing. SETTING: North London Ashkenazi-Jewish (AJ) population. POPULATION/SAMPLE: AJ women/men. METHODS: Population-based RCT (1:1). Participants were recruited through self-referral, following pre-test genetic counselling from the North London AJ population. INCLUSION CRITERIA: AJ women/men >18 years old; exclusion-criteria: prior BRCA testing or first-degree relatives of BRCA-carriers. INTERVENTIONS: Genetic testing for three Jewish BRCA founder-mutations: 185delAG (c.68_69delAG), 5382insC (c.5266dupC) and 6174delT (c.5946delT), for (i) all participants in PS arm; (ii) those fulfilling FH/clinical criteria in FH arm. Linear mixed models and appropriate contrast tests were used to analyse the impact of BRCA testing on psychological and quality-of-life outcomes over 3 years. MAIN OUTCOME MEASURES: Validated questionnaires (HADS/MICRA/HAI/SF12) used to analyse psychological wellbeing/quality-of-life outcomes at baseline/1-year/2-year/3-year follow up. RESULTS: In all, 1034 individuals (691 women, 343 men) were randomised to PS (n = 530) or FH (n = 504) arms. There was a statistically significant decrease in anxiety (P = 0.046) and total anxiety-&-depression scores (P = 0.0.012) in the PS arm compared with the FH arm over 3 years. No significant difference was observed between the FH and PS arms for depression, health-anxiety, distress, uncertainty, quality-of-life or experience scores associated with BRCA testing. Contrast tests showed a decrease in anxiety (P = 0.018), health-anxiety (P < 0.0005) and quality-of-life (P = 0.004) scores in both PS and FH groups over time. Eighteen of 30 (60%) BRCA carriers identified did not fulfil clinical criteria for BRCA testing. Total BRCA prevalence was 2.9% (95% CI 1.97-4.12%), BRCA1 prevalence was 1.55% (95% CI 0.89-2.5%) and BRCA2 prevalence was 1.35% (95% CI 0.74-2.26%). CONCLUSION: Population-based AJ BRCA testing does not adversely affect long-term psychological wellbeing or quality-of-life, decreases anxiety and could identify up to 150% additional BRCA carriers. TWEETABLE ABSTRACT: Population BRCA testing in Ashkenazi Jews reduces anxiety and does not adversely affect psychological health or quality of life.


Assuntos
Ansiedade , Detecção Precoce de Câncer , Genes BRCA1 , Genes BRCA2 , Síndrome Hereditária de Câncer de Mama e Ovário , Qualidade de Vida , Adulto , Ansiedade/fisiopatologia , Ansiedade/prevenção & controle , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/psicologia , Feminino , Predisposição Genética para Doença/psicologia , Testes Genéticos/métodos , Testes Genéticos/estatística & dados numéricos , Síndrome Hereditária de Câncer de Mama e Ovário/diagnóstico , Síndrome Hereditária de Câncer de Mama e Ovário/etnologia , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Síndrome Hereditária de Câncer de Mama e Ovário/psicologia , Humanos , Judeus/genética , Judeus/estatística & dados numéricos , Londres/epidemiologia , Masculino , Anamnese/estatística & dados numéricos , Incerteza
9.
J Environ Manage ; 253: 109662, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31630061

RESUMO

Conventional approaches to environmental governance and management are limited in their responses to uncertainty and complexity of social-ecological system (SES) change. Prevailing neoliberal and efficiency-based mindsets tend to focus on avoiding risk and creating "fail-safe" systems. In the last decade, resilience thinking has emerged as a means to transition from risk-averse, and command-and-control governance approaches towards those that are more adaptive, innovative and collaborative. To examine the practical usefulness of a resilience thinking approach, we used a complex, multi-layered case study of Tasmanian coastal governance. Drawing on the diverse expertise and a variety of key governance actors, we identified crucial problems being experienced with the Tasmanian coastal governance regime and discussed potential contributions of resilience thinking to address them. Thematic analysis of the results revealed three major contributions: resilience thinking (1) provides a way to think about change and uncertainty; (2) is compatible with proactive and entrepreneurial leadership; and (3) effectively considers issues of scale in the decision-making process. We conclude by offering practical suggestions towards devolved leadership and improved cross-scale collaboration, and consider the possibility of a hybrid resilience and risk-based approach to coastal management and governance.


Assuntos
Conservação dos Recursos Naturais , Política Ambiental , Austrália , Ecossistema , Incerteza
11.
Expert Rev Pharmacoecon Outcomes Res ; 19(6): 749-753, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31825682

RESUMO

Background: Agreements between payers and pharmaceutical/medical device companies are widely implemented to address financial and clinical uncertainties. We analyzed the main characteristics of these agreements in Israel from 2011-2018.Research design and methods: We reviewed all agreements implemented during the study period. Information regarding the type of agreement, therapeutic indications, its time frame and the total budget involved are presented.Results: A total of 56 agreements were signed since 2011, of which 53 (95%) were financial-based and 50 (89%) referred to pharmaceuticals. The annual number of agreements increased from one in 2011 to 21 in 2018. The main therapeutic areas covered were: oncology (41%), hepatitis C (16%), neurology (11%), respiratory (9%), and cardiovascular (7%). The proportion of the annual budget allocated subject to these agreements increased accordingly from 3% in 2011 to 73% in 2018. The majority (63%) of the agreements were signed for 5 years, 9% were shorter-term and 20% have no time-limit. In 14 (44%) of the financial-based agreements implemented through 2017, the actual utilization exceeded the pre-specified threshold and the companies reimbursed the health-plans accordingly.Conclusions: The number of agreements and the allocated budget subject to these agreements increased substantially in recent years. Most agreements are financial-based that, in many cases, shifted the short-term financial risk from health-plans to the industry.


Assuntos
Indústria Farmacêutica/organização & administração , Acesso aos Serviços de Saúde/economia , Programas Nacionais de Saúde/organização & administração , Participação no Risco Financeiro/organização & administração , Orçamentos , Indústria Farmacêutica/economia , Serviços de Saúde/economia , Humanos , Israel , Programas Nacionais de Saúde/economia , Mecanismo de Reembolso/economia , Participação no Risco Financeiro/economia , Incerteza
12.
Behav Brain Sci ; 42: e252, 2019 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-31826784

RESUMO

Hoerl & McCormack suggest that saving tools does not require temporal reasoning. However, we identify a class of objects that are only possessed (i.e., saved) in anticipation of future needs. We propose that investigating these future-oriented objects may help identify temporal reasoning in populations where this ability is uncertain.


Assuntos
Cognição , Resolução de Problemas , Incerteza
13.
Ying Yong Sheng Tai Xue Bao ; 30(11): 3991-4002, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31833713

RESUMO

As one of the three basic theories of landscape architecture in China, landscape ecology provides a powerful tool for leading landscape architecture in the way from experience- to evidence-based. By systematically reviewing literatures, we explored the advantages and necessity of applying landscape ecology theories and methods in landscape architecture, and summarized the interdisciplinary research hotspot and progress, including research subject, scientific foundation of planning or design, and the landscape performance for improving human wellbeing. We proposed the prior topics on the combination of landscape ecology and landscape architecture to meet the needs of planning and design in practice, including studying the landscape connotation and classification system to serve the multi-disciplinary and multi-sectors, evaluating landscape performance and quantifying the planning and design parameters for the decision-making, studying the coupling system of landscape pattern and ecological processes for solving environmental problems of human settlement and to decrease uncertainties of planning and design, studying how to enhance the capacity of landscape service for human wellbeing. We proposed to promote the application of landscape ecology comprehensive researches into practice, to consolidate the scientific basis of planning and design in landscape architecture, and to construct a practice-oriented scientific research system to bridge the gap between theory and practice.


Assuntos
Conservação dos Recursos Naturais , Ecologia , China , Tomada de Decisões , Ecossistema , Humanos , Incerteza
16.
Lancet ; 394(10211): 1801-1802, 2019 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-31741448
17.
Lancet ; 394(10211): 1802, 2019 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-31741449
19.
Eat Behav ; 35: 101340, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31731235

RESUMO

Two dimensions of perfectionism related to eating disorder (ED) symptoms are evaluative concerns and high standards. Evaluative concerns are consistently linked with ED symptoms, whereas there are conflicting results regarding high standards and ED symptoms. High standards are unrelated to ED symptoms in some studies and are linked to higher ED symptoms in others. Intolerance of uncertainty (IU) may influence the relation between high standards and ED symptoms; individuals elevated in both IU and high standards may find it distressing to be uncertain about future situations for fear of not living up to high expectations and use ED behaviors to cope with such uncertainty. In the current study (N = 216), we explored whether IU moderates the relationships between high standards and evaluative concerns and ED symptoms, both cross-sectionally and prospectively across two weeks. IU significantly moderated high standards and ED symptoms both cross-sectionally and across time while accounting for baseline ED symptoms, but did not moderate the relationship between evaluative concerns and ED symptoms. Higher standards were associated with greater ED symptoms in individuals higher, but not lower in IU. These findings suggest high standards may only contribute to ED symptoms when individuals are also high in IU.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Perfeccionismo , Incerteza , Adolescente , Estudos Transversais , Feminino , Humanos , Masculino , Estudos Prospectivos , Adulto Jovem
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