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1.
iScience ; 27(6): 110091, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38952684

RESUMO

Air pollution is a challenge for many cities. The digital economy enhances support for environmental pollution management, while the mechanisms and scaling heterogeneity remain unclear. This study explored the contribution of digital economy development to PM2.5 concentrations control in China and driving mechanisms in different economic subregions and urban agglomerations. Results show that the spillover transfer effect on air pollution mitigation far exceeded the direct effect at different scales. At the national scale, the air pollution mitigation effect of digital economy was mainly through empowering industrial structure optimization and green technology innovation, while it also affected economic subregions and urban agglomerations through varying scenario combinations of pathways with structural optimization, green production, resource allocation, and technology innovation. Research findings provide support for cross-regional joint management strategies of digital economy and air quality and designing regionally differentiated pollution control pathways in the digital economy dimension.

2.
J Therm Biol ; 119: 103779, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38159465

RESUMO

Tree-induced cooling benefits are associated with various factors, such as canopy morphology, surface cover, and environmental configuration. However, limited studies have analyzed the sensitivity of tree-induced cooling effects to the combination of such factors. Most studies have focused on 1.5-m cooling performance, and few studies on the variability of the under-tree vertical cooling performance. Therefore, this study aims to investigate the vertical cooling performance of different combinations of trees and surface covers. The study was completed in Chongqing, China, with field experiments capturing vertical air temperature and wind speed at 0.5, 1.0, 1.5, 2.0 and 2.5 m under two typical combinations of "tree + grass" (ComA) and "tree + shrubs" (ComB), and capturing 1.5 m microclimatic environments of a control group with hard pavement without tree shade (REF). The results show that at an average ambient temperature of 33 °C, the maximum air-cooling temperatures for ComA and ComB were 2.46 °C and 1.78 °C, respectively. An increase in the ambient temperature corresponded to a decrease in the cooling effect difference between ComA and ComB. ComA had a maximum vertical temperature difference of 1.01 °C between H1.5m and H2.0m. Between H2.5m and H2.0m, the maximum vertical temperature difference for ComB was 1.64 °C. This study explored the changing patterns of under-tree vertical temperatures under different tree and surface cover combinations, conducive to clarifying the key elements affecting tree cooling performance. The results have implications for accurate thermal comfort assessments and provide a theoretical basis for fine-tuning the design of under-tree spaces.


Assuntos
Temperatura Baixa , Árvores , Temperatura , Microclima , Vento , Cidades
3.
Br J Cancer ; 128(7): 1267-1277, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36646808

RESUMO

BACKGROUND: To develop and test a Prostate Imaging Stratification Risk (PRISK) tool for precisely assessing the International Society of Urological Pathology Gleason grade (ISUP-GG) of prostate cancer (PCa). METHODS: This study included 1442 patients with prostate biopsy from two centres (training, n = 672; internal test, n = 231 and external test, n = 539). PRISK is designed to classify ISUP-GG 0 (benign), ISUP-GG 1, ISUP-GG 2, ISUP-GG 3 and ISUP GG 4/5. Clinical indicators and high-throughput MRI features of PCa were integrated and modelled with hybrid stacked-ensemble learning algorithms. RESULTS: PRISK achieved a macro area-under-curve of 0.783, 0.798 and 0.762 for the classification of ISUP-GGs in training, internal and external test data. Permitting error ±1 in grading ISUP-GGs, the overall accuracy of PRISK is nearly comparable to invasive biopsy (train: 85.1% vs 88.7%; internal test: 85.1% vs 90.4%; external test: 90.4% vs 94.2%). PSA ≥ 20 ng/ml (odds ratio [OR], 1.58; p = 0.001) and PRISK ≥ GG 3 (OR, 1.45; p = 0.005) were two independent predictors of biochemical recurrence (BCR)-free survival, with a C-index of 0.76 (95% CI, 0.73-0.79) for BCR-free survival prediction. CONCLUSIONS: PRISK might offer a potential alternative to non-invasively assess ISUP-GG of PCa.


Assuntos
Aprendizado Profundo , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Gradação de Tumores , Próstata/diagnóstico por imagem , Próstata/cirurgia , Próstata/patologia , Imageamento por Ressonância Magnética
4.
Front Public Health ; 10: 1011391, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36408005

RESUMO

Actively addressing urban heat challenges is an urgent task for numerous cities. Existing studies have primarily developed heat mitigation strategies and analyzed their cooling performance, while the adaptation strategies are far from comprehensive to protect citizens from heat-related illnesses and deaths. To address this research gap, this paper aims to enhance people's adaptation capacity by investigating walkability within fifteen-minute cities (FMC). Taking cognizance of thermal comfort, health, and safety, this paper developed a dynamic attenuation model (DAM) of heat stress, along with heat stress aggravation, continuance, and alleviation. An indicator of remaining tolerant heat discomfort (R t ) was proposed with the integration of the Universal Thermal Climate Index (UTCI) to assess heat-related walkability. Following an empirical study among 128 residents in Mianyang, China, and assessing four levels of heat stress, the maximum tolerant heat discomfort was determined to be 60 min. Furthermore, the DAM was applied to an FMC with 12 neighborhoods in Fucheng, Mianyang, China. The results indicate that for each neighborhood, the street was generally walkable with an R t ranging between 15 and 30 min, after walking for 900 m. A population-based FMC walkability was further determined, finding that the core area of the FMC was favorable for walking with an R t of 45-46 min, and the perpetual areas were also walkable with an R t of 15-30 min. Based on these results, suggestions on the frequency of public services (frequently used, often used, and occasionally used) planning were presented. Overall, this paper provides a theoretical model for analyzing walkability and outlines meaningful implications for planning heat adaptation in resilient, safe, comfortable, and livable FMCs.


Assuntos
Planejamento Ambiental , Termotolerância , Humanos , Cidades , Características de Residência , Caminhada
5.
Front Public Health ; 9: 788922, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071170

RESUMO

The suitability and feasibility of public-private partnership (PPP) patterns in a rural context have not been well-documented and understood. To address this research gap and practical plight, this study aims to analyze the rural resident's willingness to pay for and participate in the improvement of rural sanitation facilities, and further explore the drivers and barriers affecting their decisions. This study was performed in rural areas of three western provinces, including Shaanxi, Ningxia, and Inner Mongolia, of western China's rural areas by conducting a survey on 1,248 rural residents. In Inner Mongolia, the proportion of respondents who were willing to pay was highest, while the proportion of respondents who may provide labor was lowest among the three provinces. Respondents from Ningxia had the least willing to pay, and respondents from Shaanxi had the highest willingness to participate. Overall, respondents' rural (living) duration time, personal interest in local government notice, and the latest time when the sanitation facilities were improved could significantly affect their willingness. In Inner Mongolia, occupation and water availability could significantly influence respondents' willingness, and both gender and health conditions had significant impacts. In Ningxia, respondents' personal interest in local government notice had a notable impact on willingness, and low-income respondents showed a more notable willingness to pay and participate. In Shaanxi, occupation and water availability could significantly influence respondents' willingness. Respondents' personal interest in local government notice had a notable impact on their willingness. This study is of significant importance to understand rural resident's participation in sanitation infrastructure improvement to support relevant PPP projects, and is important to solve poverty-caused dilemmas.


Assuntos
Financiamento Pessoal , Saneamento , China , Humanos , População Rural , Água
6.
J Magn Reson Imaging ; 53(4): 1210-1219, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33075177

RESUMO

BACKGROUND: There is a requirement for a personalized strategy to make MRI more accessible to men with suspicion of clinically significant prostate cancer (CSPC). PURPOSE: To evaluate an optimized (Op)-MRI compared with biparametric (Bp)-MRI and multiparametric (Mp)-MRI for the diagnosis of CSPC. STUDY TYPE: Two-center, retrospective. SUBJECTS: A total of 346 patients from center 1 and 292 patients from center 2. FIELD STRENGTH/SEQUENCE: 3.0T scanners, T2 -weighted imaging (T2 WI), diffusion-weighted imaging (DWI), and dynamic contrast-enhanced (DCE) imaging. ASSESSMENT: Four radiologists interpreted the Bp-MRI (T2 WI and DWI) and Mp-MRI (T2 WI, DWI, and DCE) independently according to the Prostate Imaging Reporting and Data System (PI-RADS). For Op-MRI, two radiologists used an adjusted decision rule on Bp-MRI-assessed PI-RADS 3 lesions by determining early enhancement of DCE. Pathologies at biopsy and/or prostatectomy specimens were used as standard references. STATISTICAL TESTS: Performance was assessed using receiver operating characteristic (ROC) curves. Kappa statistics were used to assess interobserver variability. RESULTS: Interreader agreement was excellent for all three MRI assessments (all κ values >0.80). Op-MRI had comparable sensitivity (senior/junior: 90.9% [261/287] / 91.6% [263/287]) and higher specificity (78.1% [274/351] /74.4% [261/351]) compared with Mp-MRI (sensitivity: 92.3% [265/287] / 93.7% [269/287]; specificity: 67.8% [238/351] / 68.1% [239/351]) and Bp-MRI (sensitivity: 91.6% [263/287] / 93.4% [268/287]; specificity: 71.2% [250/351] / 70.1% [246/351]) for the diagnosis of CSPC. Compared to Mp-MRI, Op-MRI spared biopsy in 80.7% (515/638) of DCE scans with similar performance accuracy. Compared to Bp-MRI, Op-MRI downgraded 25.2% (31/123) of lesions at a cost of missing 6.5% (3/46) of malignancies, and upgraded 45.5% (56/123) of lesions with a positive predictive value of 62.5% (35/56) in 123 equivocal findings. DATA CONCLUSION: The Op-MRI, using an adjusted PI-RADS decision rule, did not compromise diagnostic accuracy with sparing biopsy in 80.7% of DCE scans compared to Mp-MRI, and outperformed Bp-MRI by regrading PI-RADS lesions. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 2.


Assuntos
Neoplasias da Próstata , Imagem de Difusão por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética , Masculino , Prostatectomia , Neoplasias da Próstata/diagnóstico por imagem , Estudos Retrospectivos
7.
JMIR Mhealth Uhealth ; 7(4): e11500, 2019 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-30973342

RESUMO

BACKGROUND: After a mobile health (mHealth) app is created, an important step is to evaluate the usability of the app before it is released to the public. There are multiple ways of conducting a usability study, one of which is collecting target users' feedback with a usability questionnaire. Different groups have used different questionnaires for mHealth app usability evaluation: The commonly used questionnaires are the System Usability Scale (SUS) and Post-Study System Usability Questionnaire (PSSUQ). However, the SUS and PSSUQ were not designed to evaluate the usability of mHealth apps. Self-written questionnaires are also commonly used for evaluation of mHealth app usability but they have not been validated. OBJECTIVE: The goal of this project was to develop and validate a new mHealth app usability questionnaire. METHODS: An mHealth app usability questionnaire (MAUQ) was designed by the research team based on a number of existing questionnaires used in previous mobile app usability studies, especially the well-validated questionnaires. MAUQ, SUS, and PSSUQ were then used to evaluate the usability of two mHealth apps: an interactive mHealth app and a standalone mHealth app. The reliability and validity of the new questionnaire were evaluated. The correlation coefficients among MAUQ, SUS, and PSSUQ were calculated. RESULTS: In this study, 128 study participants provided responses to the questionnaire statements. Psychometric analysis indicated that the MAUQ has three subscales and their internal consistency reliability is high. The relevant subscales correlated well with the subscales of the PSSUQ. The overall scale also strongly correlated with the PSSUQ and SUS. Four versions of the MAUQ were created in relation to the type of app (interactive or standalone) and target user of the app (patient or provider). A website has been created to make it convenient for mHealth app developers to use this new questionnaire in order to assess the usability of their mHealth apps. CONCLUSIONS: The newly created mHealth app usability questionnaire-MAUQ-has the reliability and validity required to assess mHealth app usability.


Assuntos
Inquéritos e Questionários/normas , Avaliação da Tecnologia Biomédica/métodos , Telemedicina/normas , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pennsylvania , Psicometria/instrumentação , Psicometria/métodos , Psicometria/normas , Reprodutibilidade dos Testes , Inquéritos e Questionários/estatística & dados numéricos , Avaliação da Tecnologia Biomédica/estatística & dados numéricos , Telemedicina/estatística & dados numéricos , Estudos de Validação como Assunto
8.
Artigo em Inglês | MEDLINE | ID: mdl-30832282

RESUMO

The ecological status of the semi-arid steppes in China is fragile. Under the long-term and high-intensity development of mining, the ecological integrity and biodiversity of steppe landscapes have been destroyed, causing soil pollution, grassland degradation, landscape function defect, and so on. Previous studies have mainly focused on ecosystem health assessment in mining areas. Landscape ecological health (LEH) pays more attention to the interactions between different ecosystems. Therefore, the ecological assessment of mining cities is more suitable on a landscape scale. Meanwhile, the existing LEH assessment index systems are not applicable in ecologically fragile areas with sparse population, underdeveloped economy, and in relatively small research areas. The purpose of this study was to construct a LEH assessment index system and evaluate the LEH of a mining city located in a semi-arid steppe. Xilinhot is a typical semi-arid steppe mining city in China. The contradictions between the human, land and ecological environment are serious. A new model Condition, Vigor, Organization, Resilience, and Ecosystem (CVORE) model was constructed that integrated five subsystems (services) from the perspectives of ecology, landscape ecology, mining science, and geography. This study used the CVORE model to systematically evaluate the LEH in Xilinhot city in terms of five LEH levels, including very healthy, healthy, sub-healthy, unhealthy and morbid landscape. Research results show that the areas of the very healthy, healthy, sub-healthy, unhealthy and morbid landscapes are 13.23, 736.35, 184.5, 66.76 and 20.63 km², respectively. The healthy landscapes area accounts for 72.08% and most grasslands are healthy. The sub-healthy landscapes are mainly located around areas with higher disturbances due to human activities. The morbid or unhealthy landscapes are concentrated in the mining areas. The proposed CVORE model can enrich the foundations for the quantitative assessment of Landscape Ecological Health of Mining Cities in Semi-arid Steppe (LEHMCSS). This study provided a new LEH assessment approach (CVORE model), which can support landscape ecological restoration, ecological environmental protection and urban planning of the semi-arid steppe mining cities.


Assuntos
Planejamento de Cidades , Conservação dos Recursos Naturais , Ecossistema , Mineração , Biodiversidade , China , Cidades , Humanos
9.
Bioresour Technol ; 275: 338-344, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30597395

RESUMO

Commercial cellulosic ethanol plants require mature and year-round biomass feedstock supply. Decentralizing pretreatment operation from central ethanol plant into local regional biomass collection depots provides an important solution to reach this goal. In this study, we introduced a newly established pretreatment technology, dry acid pretreatment, into the decentralized pretreatment operation by its advantages on zero wastewater generation and high volumetric density. Collection radius of crop residues feedstock is extended to nearly 100 km by decentralizing dry acid pretreatment, and biorefinery scale for cellulosic ethanol production is increased to the scale of modern petroleum refining factories in the densified agricultural regions in China and USA with the minimum ethanol selling price of below $2/gal. The technology overcomes the barrier of cellulosic ethanol cost increase with increasing biomass collection range, and provides a methodology for optimal supply method of large biorefinery plants in agricultural countries.


Assuntos
Biomassa , Etanol/química , Ácidos/química , Custos e Análise de Custo , Etanol/economia
10.
Bioresour Technol ; 271: 196-201, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30268811

RESUMO

l-Lysine is a commodity amino acid produced from starch feedstock. Various alternative feedstocks had been used for l-lysine production, but the yield was very low. This study took the first preliminary investigation on l-lysine production from lignocellulose for the replacement of food-crop starch. Corn stover was dry acid pretreated and biodetoxified, then used for enzymatic hydrolysis and l-lysine fermentation by an industrial Corynebacterium glutamicum strain. Various fermentation parameters, nutrient additions, and operation variables were applied and finally 33.8 g/L of l-lysine was obtained. This l-lysine titer is still below that of starch based fermentation, but already 3-5 folds greater than that of other alternative feedstocks based fermentation. A techno-economic analysis was conducted and the minimum selling price of l-lysine (hydrochloride form) was calculated to be $2.445 per kg. The cost reduction by the future improvement could fill the technical and economic gap between the cellulosic and starch based l-lysine production.


Assuntos
Fermentação , Lignina/metabolismo , Lisina/biossíntese , Corynebacterium glutamicum/metabolismo , Análise Custo-Benefício , Hidrólise , Amido/metabolismo , Zea mays/metabolismo
11.
Accid Anal Prev ; 120: 281-294, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30179734

RESUMO

The primary objective of this study was to investigate how trip pattern variables extracted from large-scale taxi GPS data contribute to the spatially aggregated crashes in urban areas. The following five types of data were collected: crash data, large-scale taxi GPS data, road network attributes, land use features and social-demographic data. A data-driven modeling approach based on Latent Dirichlet Allocation (LDA) was proposed for discovering hidden trip patterns from a taxi GPS dataset, and a total of fifty trip patterns were identified. The collected data and the identified trip patterns were further aggregated into167 ZIP Code Tabulation Areas (ZCTA). Random forest technique was used to identify the factors that contributed to total, PDO and fatal-plus-injury crashes in the selected ZCTAs during the study period. Geographically weighted Poisson regression (GWPR) models were then developed to establish a relationship between the crashes and the contributing factors selected by the random forest technique. Comparative analyses were conducted to compare the performance of the GWPR models that considered traditional traffic exposure variables only, trip pattern variables only, and both traditional exposure and trip pattern variables. The model specification results suggest that the trip pattern variables significantly affected the crash counts in the selected ZCTAs, and the models that considered both the traditional traffic exposure and the trip pattern variables had the best goodness-of-fit in terms of the lowest MAD and AICc values.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Automóveis/estatística & dados numéricos , Cidades/estatística & dados numéricos , Segurança/estatística & dados numéricos , Sistemas de Informação Geográfica , Humanos , New York , Fatores Socioeconômicos , Análise Espaço-Temporal
12.
Bioresour Technol ; 219: 123-131, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27484668

RESUMO

High titer gluconic acid and xylonic acid were simultaneously fermented by Gluconobacter oxydans DSM 2003 using corn stover feedstock after dry dilute sulfuric acid pretreatment, biodetoxification and high solids content hydrolysis. Maximum sodium gluconate and xylonate were produced at the titer of 132.46g/L and 38.86g/L with the overall yield of 97.12% from glucose and 90.02% from xylose, respectively. The drawbacks of filamentous fungus Aspergillus niger including weak inhibitor tolerance, large pellet formation and no xylose utilization were solved by using the bacterium strain G. oxydans. The obtained sodium gluconate/xylonate product was highly competitive as cement retarder additive to the commercial product from corn feedstock. The techno-economic analysis (TEA) based on the Aspen Plus modeling was performed and the minimum sodium gluconate/xylonate product selling price (MGSP) was calculated as $0.404/kg. This study provided a practical and economic competitive process of lignocellulose utilization for production of value-added biobased chemicals.


Assuntos
Fermentação , Gluconatos/metabolismo , Gluconobacter oxydans/metabolismo , Lignina/metabolismo , Ácido Oxâmico/análogos & derivados , Biomassa , Custos e Análise de Custo , Glucose/metabolismo , Lignina/química , Ácido Oxâmico/metabolismo , Ácidos Sulfúricos/química , Xilose/metabolismo , Zea mays
13.
Bioprocess Biosyst Eng ; 39(1): 133-40, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26541585

RESUMO

Cost reduction on cellulase enzyme usage has been the central effort in the commercialization of fuel ethanol production from lignocellulose biomass. Therefore, establishing an accurate evaluation method on cellulase enzyme cost is crucially important to support the health development of the future biorefinery industry. Currently, the cellulase cost evaluation methods were complicated and various controversial or even conflict results were presented. To give a reliable evaluation on this important topic, a rigorous analysis based on the Aspen Plus flowsheet simulation in the commercial scale ethanol plant was proposed in this study. The minimum ethanol selling price (MESP) was used as the indicator to show the impacts of varying enzyme supply modes, enzyme prices, process parameters, as well as enzyme loading on the enzyme cost. The results reveal that the enzyme cost drives the cellulosic ethanol price below the minimum profit point when the enzyme is purchased from the current industrial enzyme market. An innovative production of cellulase enzyme such as on-site enzyme production should be explored and tested in the industrial scale to yield an economically sound enzyme supply for the future cellulosic ethanol production.


Assuntos
Celulase/economia , Celulose/economia , Etanol/economia , Modelos Econômicos , Celulase/química , Celulose/química , Custos e Análise de Custo , Etanol/química
14.
Huan Jing Ke Xue ; 37(10): 3789-3797, 2016 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964410

RESUMO

To study the features and ecological risk of PAHs in surface water from Yangtze River, 19 water samples were collected from the main stream and branch of Yangtze River in August 2015. Solid phase extraction method was used to extract PAHs, and the concentrations of the 16 priority PAHs were determined using GC-MS. The results indicated that the concentration of total PAHs (∑PAHs) in the surface water ranged from 17.7-110 ng·L-1 with an average value of 42.6 ng·L-1. The predominant PAHs in the water were PAHs with 2-3 rings, accounting for 67.7% of ∑PAHs. The results of molecular diagnostic ratios indicated that the origin of PAHs was mostly combustion sources, including fossil fuel and biomass combustion. PMF model was used to quantitatively acquire the source contribution of PAHs, which indicated that four sources were identified and their contribution rates were respectively biomass and coal combustion (40.1%), petroleum source (19.6%), traffic source (17.5%) and coke oven source (22.8%). The results of ecological risk assessment indicated that PAHs with 2-3 rings had a relatively high risk level, and Wujiang station and lower reach had a relatively high risk level based on risk quotient. Overall, the ecological risk of PAHs in the Yangtze River was at a relatively low level.

15.
Bioresour Technol ; 198: 803-10, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26454367

RESUMO

Technological potentials of l-lactic acid production from corn stover feedstock were investigated by experimental and techno-economic studies. An optimal performance with 104.5 g/L in l-lactic acid titer and 71.5% in overall yield from cellulose in corn stover to l-lactic acid using an engineered Pediococcus acidilactici strain were obtained by overcoming several technical barriers. A rigorous Aspen plus model for l-lactic acid production starting from dry dilute acid pretreated and biodetoxified corn stover was developed. The techno-economic analysis shows that the minimum l-lactic acid selling price (MLSP) was $0.523 per kg, which was close to that of the commercial l-lactic acid produced from starch feedstock, and 24% less expensive than that of ethanol from corn stover, even though the xylose utilization was not considered. The study provided a prototype of industrial application and an evaluation model for high titer l-lactic acid production from lignocellulose feedstock.


Assuntos
Ácido Láctico , Zea mays , Resíduos Industriais/análise , Ácido Láctico/análise , Ácido Láctico/química , Ácido Láctico/metabolismo , Lignina , Modelos Teóricos , Águas Residuárias/análise , Zea mays/química , Zea mays/metabolismo
16.
Health Aff (Millwood) ; 34(7): 1225-33, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26085486

RESUMO

The federal government encourages public support for charitable activities by allowing people to deduct donations to tax-exempt organizations on their income tax returns. Tax-exempt hospitals are major beneficiaries of this policy because it encourages donations to the hospitals while shielding them from federal and state tax liability. In exchange, these hospitals must engage in community benefit activities, such as providing care to indigent patients and participating in Medicaid. The congressional Joint Committee on Taxation estimated the value of the nonprofit hospital tax exemption at $12.6 billion in 2002--a number that included forgone taxes, public contributions, and the value of tax-exempt bond financing. In this article we estimate that the size of the exemption reached $24.6 billion in 2011. The Affordable Care Act (ACA) brings a new focus on community benefit activities by requiring tax-exempt hospitals to engage in communitywide planning efforts to improve community health. The magnitude of the tax exemption, coupled with ACA reforms, underscores the public's interest not only in community benefit spending generally but also in the extent to which nonprofit hospitals allocate funds for community benefit expenditures that improve the overall health of their communities.


Assuntos
Hospitais Filantrópicos/economia , Organizações sem Fins Lucrativos/economia , Isenção Fiscal/economia , Impostos/economia , Relações Comunidade-Instituição , Humanos , Medicaid , Patient Protection and Affordable Care Act , Cuidados de Saúde não Remunerados/economia , Estados Unidos
17.
Artigo em Chinês | MEDLINE | ID: mdl-24358753

RESUMO

OBJECTIVE: To evaluate the performance of schistosomiasis detection and treatment program in Hubei Province in 2011, so as to enhance the benefit and management of the program. METHODS: In 63 schistosomiasis epidemic counties of Hubei Province, there were 3 types of endemic situation, that was endemic controlled, transmission controlled, and transmission interrupted. Six counties (districts) in each type were selected by the stratified random sampling method. The data including schistosomiasis detection and treatment, fund utilization and others were collected and analyzed statistically in 2011. RESULTS: The completion rate of schistosomiasis detection task was 103.9% and the completion rate of chemotherapy task 106.9%. The total fund was 73.815 million Yuan. The detection cost accounted for 12.0% while the chemotherapy cost accounted for 4.9%. The detection cost per capita was 9.03 Yuan and the treatment cost per capita was 10.35 Yuan. The cost effectiveness ratio was 1:6.1 and the net cost effectiveness ratio was 1:5.1. CONCLUSION: The social-economic benefits in schistosomiasis control and treatment are obvious. However, the resource allocation still needs to be optimized.


Assuntos
Controle de Doenças Transmissíveis/economia , Serviços de Diagnóstico/economia , Custos de Cuidados de Saúde , Esquistossomose/diagnóstico , Esquistossomose/economia , China/epidemiologia , Controle de Doenças Transmissíveis/métodos , Análise Custo-Benefício , Fezes/parasitologia , Humanos , Esquistossomose/prevenção & controle , Esquistossomose/terapia , Recursos Humanos
18.
Sheng Wu Gong Cheng Xue Bao ; 29(3): 312-24, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23789272

RESUMO

Cellulose takes nearly 10% (W/W) dry weight of cassava tubers. In this study, the cellulase cost of different ethanol fermentation from cassava cellulose was evaluated. The processes include the direct saccharification and fermentation of original cassava cellulose residues, the direct saccharification and fermentation of pretreated cassava cellulose residues, and the simultaneous co-saccharification and fermentation of cassava starch and cassava cellulose. The results show that the cassava cellulose utilization in the first two processes were low with the enzyme cost of 13 602 and 11 659 RMB Yuan per tone of ethanol, respectively. In the third process, the final ethanol concentration increased from 101.5 g/L to 107.0 g/L when cassava cellulose and cassava starch were saccharified simultaneously. Comparing to the first two processes, the third one demonstrated the lowest enzyme cost at 3 589 RMB Yuan per ton of ethanol, which was less than the ethanol price and no additional equipment and operation cost input were added. The conclusion provided a practical way of cassava cellulose utilization in cassava ethanol industry.


Assuntos
Celulase/economia , Celulose/metabolismo , Etanol/economia , Fermentação , Manihot/metabolismo , Biotecnologia/economia , Biotecnologia/métodos , Análise Custo-Benefício , Etanol/metabolismo , Saccharomyces cerevisiae/metabolismo
19.
Bioresour Technol ; 134: 298-306, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23500588

RESUMO

Cassava cellulose accounts for one quarter of cassava residues and its utilization is important for improving the efficiency and profit in commercial scale cassava ethanol industry. In this study, three scenarios of cassava cellulose utilization for ethanol production were experimentally tested under same conditions and equipment. Based on the experimental results, a rigorous flowsheet simulation model was established on Aspen plus platform and the cost of cellulase enzyme and steam energy in the three cases was calculated. The results show that the simultaneous co-saccharification of cassava starch/cellulose and ethanol fermentation process (Co-SSF) provided a cost effective option of cassava cellulose utilization for ethanol production, while the utilization of cassava cellulose from cassava ethanol fermentation residues was not economically sound. Comparing to the current fuel ethanol selling price, the Co-SSF process may provide an important choice for enhancing cassava ethanol production efficiency and profit in commercial scale.


Assuntos
Biotecnologia/economia , Biotecnologia/métodos , Celulose/metabolismo , Simulação por Computador , Etanol/economia , Etanol/metabolismo , Manihot/química , Metabolismo dos Carboidratos/efeitos dos fármacos , Celulase/metabolismo , Custos e Análise de Custo , Fermentação/efeitos dos fármacos , Hidrólise/efeitos dos fármacos , Manihot/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Vapor , Ácidos Sulfúricos/farmacologia
20.
Mol Biol Evol ; 30(6): 1471-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23493260

RESUMO

MrBayes, using Metropolis-coupled Markov chain Monte Carlo (MCMCMC or (MC)(3)), is a popular program for Bayesian inference. As a leading method of using DNA data to infer phylogeny, the (MC)(3) Bayesian algorithm and its improved and parallel versions are now not fast enough for biologists to analyze massive real-world DNA data. Recently, graphics processor unit (GPU) has shown its power as a coprocessor (or rather, an accelerator) in many fields. This article describes an efficient implementation a(MC)(3) (aMCMCMC) for MrBayes (MC)(3) on compute unified device architecture. By dynamically adjusting the task granularity to adapt to input data size and hardware configuration, it makes full use of GPU cores with different data sets. An adaptive method is also developed to split and combine DNA sequences to make full use of a large number of GPU cards. Furthermore, a new "node-by-node" task scheduling strategy is developed to improve concurrency, and several optimizing methods are used to reduce extra overhead. Experimental results show that a(MC)(3) achieves up to 63× speedup over serial MrBayes on a single machine with one GPU card, and up to 170× speedup with four GPU cards, and up to 478× speedup with a 32-node GPU cluster. a(MC)(3) is dramatically faster than all the previous (MC)(3) algorithms and scales well to large GPU clusters.


Assuntos
Algoritmos , Teorema de Bayes , Biologia Computacional/métodos , Gráficos por Computador , Análise por Conglomerados , Processamento de Imagem Assistida por Computador , Cadeias de Markov , Método de Monte Carlo , Filogenia , Análise de Sequência de DNA , Software
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