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1.
J Natl Cancer Inst ; 115(10): 1188-1193, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37314971

RESUMO

BACKGROUND: Multidisciplinary cancer care (neoadjuvant chemotherapy followed by radical cystectomy or trimodality therapy) is crucial for outcome of muscle-invasive bladder cancer (MIBC), a potentially curable illness. Medicaid expansion through Affordable Care Act (ACA) increased insurance coverage especially among patients of racial minorities. This study aims to investigate the association between Medicaid expansion and racial disparity in timely treatment in MIBC. METHODS: This quasi-experimental study analyzed Black and White individuals aged 18-64 years with stage II and III bladder cancer treated with neoadjuvant chemotherapy followed by radical cystectomy or trimodality therapy from National Cancer Database 2008-2018. Primary outcome was timely treatment started within 45 days following cancer diagnosis. Racial disparity is the percentage-point difference between Black and White patients. Patients in expansion and nonexpansion states were compared using difference-in-differences and difference-in-difference-in-differences analyses, controlling for age, sex, area-level income, clinical stage, comorbidity, metropolitan status, treatment type, and year of diagnosis. RESULTS: The study included 4991 (92.3% White, n = 4605; 7.7% Black, n = 386) patients. Percentage of Black patients who received timely care increased following the ACA in Medicaid expansion states (54.5% pre-ACA vs 57.4% post-ACA) but decreased in nonexpansion states (69.9% pre-ACA vs 53.7% post-ACA). After adjusting covariates, Medicaid expansion was associated with a net 13.7 percentage-point reduction of Black-White patient disparity in timely receipt of MIBC treatment (95% confidence interval = 0.5% to 26.8%; P < .01). CONCLUSIONS: Medicaid expansion was associated with statically significant reduction in racial disparity between Black and White patients in timely multidisciplinary treatment for MIBC.


Assuntos
Medicaid , Neoplasias da Bexiga Urinária , Estados Unidos/epidemiologia , Humanos , Patient Protection and Affordable Care Act , Neoplasias da Bexiga Urinária/terapia , Grupos Raciais , Cobertura do Seguro , Músculos
2.
J Environ Manage ; 311: 114835, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35306366

RESUMO

A clear understanding of the driving factors for different ecosystem services (ESs) is quite essential for sustainable ecosystem management. It is important to strengthen research in ESs and social sustainable development to identify the main driving factors of different ESs. This study assessed carbon sequestration (CS), water yield (WY) and soil conservation (SC) from 2000 to 2018 in the Loess Plateau using CASA (The Carnegie-AmesStanford Approach), InVEST (Integrated Valuation of Ecosystem Services and Trade-offs) and RUSLE (Revised Universal Soil Loss Equation) models. The spatial heterogeneity, trade-offs and synergies and driving factors were explored in the whole Loess Plateau. The results showed that the WY, CS and SC had increased from 2000 to 2018. The spatial relationships between WY and SC, SC and CS, and WY and CS were mainly synergistic. Annual mean precipitation (MAP) was the dominant driving factor of WY, while normalized difference vegetation index (NDVI) and slope (SL) had the strongest explanatory power for CS and SC. The LU was the most critical factor affecting the ESs in the different climatic zones. These results could act as a reference for decision-makers on how to control various influencing factors of ESs to improve the local ecology under local conditions.

3.
IEEE Trans Pattern Anal Mach Intell ; 44(1): 13-31, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-32750821

RESUMO

The rapid development of deep neural networks (DNNs) in recent years can be attributed to the various techniques that address gradient explosion and vanishing. In order to understand the principle behind these techniques and develop new methods, plenty of metrics have been proposed to identify networks that are free of gradient explosion and vanishing. However, due to the diversity of network components and complex serial-parallel hybrid connections in modern DNNs, the evaluation of existing metrics usually requires strong assumptions, complex statistical analysis, or has limited application fields, which constraints their spread in the community. In this paper, inspired by the Gradient Norm Equality and dynamical isometry, we first propose a novel metric called Block Dynamical Isometry, which measures the change of gradient norm in individual blocks. Because our Block Dynamical Isometry is norm-based, its evaluation needs weaker assumptions compared with the original dynamical isometry. To mitigate challenging derivation, we propose a highly modularized statistical framework based on free probability. Our framework includes several key theorems to handle complex serial-parallel hybrid connections and a library to cover the diversity of network components. Besides, several sufficient conditions for prerequisites are provided. Powered by our metric and framework, we analyze extensive initialization, normalization, and network structures. We find that our Block Dynamical Isometry is a universal philosophy behind them. Then, we improve some existing methods based on our analysis, including an activation function selection strategy for initialization techniques, a new configuration for weight normalization, a depth-aware way to derive coefficients in SeLU, and initialization/weight normalization in DenseNet. Moreover, we propose a novel normalization technique named second moment normalization, which has 30 percent fewer computation overhead than batch normalization without accuracy loss and has better performance under micro batch size. Last but not least, our conclusions and methods are evidenced by extensive experiments on multiple models over CIFAR-10 and ImageNet.


Assuntos
Algoritmos , Redes Neurais de Computação , Benchmarking
4.
PLoS One ; 16(1): e0245981, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33493239

RESUMO

Agricultural modernization and intensification have been regarded as a significant way to support agricultural development and improve farm income in China. Agricultural cooperatives have played an important role in promoting the modernization and intensification of Chinese agricultural sector. Given the increasing concerns about environmental harm, however, it still remains unclear whether and the extent to which agricultural cooperatives contributes to reducing environmental impacts of agricultural production. Hence, this study performed an environmental evaluation using life cycle assessment for three different organization forms of grape production in Changli County, Hebei Province, China: smallholder farmers, farmer-owned cooperatives and investor-owned firm-led cooperatives. Then the results of life cycle assessment were monetarized and cost benefit analysis was used to evaluate the economic performance of these three organization forms of grape production. The results demonstrate that investor-owned firm-led cooperatives present an overall improvement in environmental and economic performance with the lowest weighted environmental index (integrating all impact categories into a single score), the highest net profit and the highest total net benefit. The results also show a difference in potential improvement in environmental impacts and economic returns between cooperatives and smallholder farmers. Additionally, the production and application of organic and chemical fertilizer and pesticide have been identified as major contributors to total environmental damage.


Assuntos
Agricultura/economia , Fazendeiros , Vitis/crescimento & desenvolvimento , Agricultura/métodos , China , Fertilizantes , Propriedade
5.
Biochim Biophys Acta Biomembr ; 1862(6): 183217, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32061646

RESUMO

As the only exposed viral protein at the membrane surface of HIV, envelope glycoprotein gp120 is responsible for recognizing host cells and mediating virus-cell membrane fusion. Available structures of gp120 indicate that it exhibits two distinct conformational states, called closed and open states. Although experimental data demonstrates that CD4 binding stabilizes open state of gp120, detailed structural dynamics and kinetics of gp120 during this process remain elusive. Here, two open-state gp120 simulation systems, one without any ligands (ligand-free) and the other complexed with CD4 (CD4-bound), were subjected to microsecond-scale molecular dynamics simulations following the conformational transitions and allosteric pathways of gp120 evaluated by using the Markov state model and a network-based method, respectively. Our results provide an atomic-resolution description of gp120 conformational transitions, suggesting that gp120 is intrinsically dynamic from the open state to closed state, whereas CD4 binding blocks these transitions. Consistent with experimental structures, five metastable conformations with different orientations of the V1/V2 region and V3 loop have been extracted. The binding of CD4 significantly enhances allosteric communications from the CD4-binding site to V3 loop and ß20-21 hairpin, resulting in high-affinity interactions with coreceptors and activation of the conformational transitions switcher, respectively. This study will facilitate the structural understanding of the CD4-binding effects on conformational transitions and allosteric pathways of gp120.


Assuntos
Regulação Alostérica/fisiologia , Antígenos CD4/metabolismo , Proteína gp120 do Envelope de HIV/metabolismo , Sítios de Ligação , Proteína gp120 do Envelope de HIV/química , Humanos , Cadeias de Markov , Simulação de Dinâmica Molecular , Ligação Proteica , Conformação Proteica
6.
Glob Chang Biol ; 25(6): 2061-2076, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30884086

RESUMO

Wetlands contain a large proportion of carbon (C) in the biosphere and partly affect climate by regulating C cycles of terrestrial ecosystems. China contains Asia's largest wetlands, accounting for about 10% of the global wetland area. Although previous studies attempted to estimate C budget in China's wetlands, uncertainties remain. We conducted a synthesis to estimate C uptake and emission of wetland ecosystems in China using a dataset compiled from published literature. The dataset comprised 193 studies, including 370 sites representing coastal, river, lake and marsh wetlands across China. In addition, C stocks of different wetlands in China were estimated using unbiased data from the China Second Wetlands Survey. The results showed that China's wetlands sequestered 16.87 Pg C (315.76 Mg C/ha), accounting for about 3.8% of C stocks in global wetlands. Net ecosystem productivity, jointly determined by gross primary productivity and ecosystem respiration, exhibited annual C sequestration of 120.23 Tg C. China's wetlands had a total gaseous C loss of 173.20 Tg C per year from soils, including 154.26 Tg CO2 -C and 18.94 Tg CH4 -C emissions. Moreover, C stocks, uptakes and gaseous losses varied with wetland types, and were affected by geographic location and climatic factors (precipitation and temperature). Our results provide better estimation of the C budget in China's wetlands and improve understanding of their contribution to the global C cycle in the context of global climate change.


Assuntos
Carbono , Áreas Alagadas , Carbono/análise , Ciclo do Carbono , China , Mudança Climática , Ecossistema , Solo/química
7.
Molecules ; 23(10)2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30287797

RESUMO

Hot spots are the subset of interface residues that account for most of the binding free energy, and they play essential roles in the stability of protein binding. Effectively identifying which specific interface residues of protein⁻protein complexes form the hot spots is critical for understanding the principles of protein interactions, and it has broad application prospects in protein design and drug development. Experimental methods like alanine scanning mutagenesis are labor-intensive and time-consuming. At present, the experimentally measured hot spots are very limited. Hence, the use of computational approaches to predicting hot spots is becoming increasingly important. Here, we describe the basic concepts and recent advances of machine learning applications in inferring the protein⁻protein interaction hot spots, and assess the performance of widely used features, machine learning algorithms, and existing state-of-the-art approaches. We also discuss the challenges and future directions in the prediction of hot spots.


Assuntos
Biologia Computacional , Domínios e Motivos de Interação entre Proteínas/genética , Mapeamento de Interação de Proteínas/métodos , Proteínas/química , Alanina/química , Algoritmos , Sítios de Ligação , Bases de Dados de Proteínas , Aprendizado de Máquina , Ligação Proteica , Conformação Proteica , Proteínas/genética
8.
ISA Trans ; 76: 88-96, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29548679

RESUMO

Locating a pre-given number of key nodes that are connected to external control sources so as to minimize the cost of controlling a directed network x(t)=Ax(t)+Bu(t), known as the minimum cost control problem, is of critical importance. Considering a network consisting of N nodes with M external control sources, the state of art techniques employ iterative searching to determine the input matrix B that characterizes how nodes are connected to external control sources, in a matrix space RN×M. The nodes having M largest values of a defined importance index are selected as key nodes. However, such techniques may suffer from large performance penalty in some networks due to the diversity of real-life networks. To address this outstanding issue, we propose an iterative method, termed "L0-norm constraint based projected gradient method" (LPGM). We probabilistically search the input matrix in each iteration by restricting its L0 norm as a fixed value M, which implies that each control source is always only connected to a single key node during the whole searching process. Simulation results show that the solution always efficiently approaches a suboptimal key node set in a few iterations. These results provide a new point of view regarding the key nodes selection in the minimum cost control of directed networks.

9.
Parasite ; 24: 1, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28098070

RESUMO

The present review discusses the findings of cryptosporidiosis research conducted in cattle in China and highlights the currently available information on Cryptosporidium epidemiology, genetic diversity, and distribution in China, which is critical to understanding the economic and public health importance of cryptosporidiosis transmission in cattle. To date, 10 Cryptosporidium species have been detected in cattle in China, with an overall infection rate of 11.9%. The highest rate of infection (19.5%) was observed in preweaned calves, followed by that in juveniles (10.69%), postweaned juveniles (9.0%), and adult cattle (4.94%). The dominant species were C. parvum in preweaned calves and C. andersoni in postweaned, juvenile, and adult cattle. Zoonotic Cryptosporidium species (C. parvum and C. hominis) were found in cattle, indicating the possibility of transmission between humans and cattle. Different cattle breeds had significant differences in the prevalence rate and species of Cryptosporidium. This review demonstrates an age-associated, breed-associated, and geographic-related occurrence of Cryptosporidium and provides references for further understanding of the epidemiological characteristics, and for preventing and controlling the disease.


Assuntos
Doenças dos Bovinos/epidemiologia , Criptosporidiose/epidemiologia , Distribuição por Idade , Animais , Bovinos , Doenças dos Bovinos/economia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/prevenção & controle , China/epidemiologia , Criptosporidiose/economia , Criptosporidiose/prevenção & controle , Criptosporidiose/transmissão , Cryptosporidium/classificação , Cryptosporidium/genética , Variação Genética , Prevalência
10.
Nanotoxicology ; 10(10): 1545-1554, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27781563

RESUMO

Nano iron oxide particles are beneficial to our daily lives through their use in paints, construction materials, biomedical imaging and other industrial fields. However, little is known about the possible risks associated with the current exposure level of engineered nano iron oxides (nano-FeOX) to organisms in the environment. The goal of this study was to predict the release of nano-FeOX to the environment and assess their risks for surface waters in the EU and Switzerland. The material flows of nano-FeOX to technical compartments (waste incineration and waste water treatment plants) and to the environment were calculated with a probabilistic modeling approach. The mean value of the predicted environmental concentrations (PECs) of nano-FeOX in surface waters in the EU for a worst-case scenario (no particle sedimentation) was estimated to be 28 ng/l. Using a probabilistic species sensitivity distribution, the predicted no-effect concentration (PNEC) was determined from ecotoxicological data. The risk characterization ratio, calculated by dividing the PEC by PNEC values, was used to characterize the risks. The mean risk characterization ratio was predicted to be several orders of magnitude smaller than 1 (1.4 × 10-4). Therefore, this modeling effort indicates that only a very limited risk is posed by the current release level of nano-FeOX to organisms in surface waters. However, a better understanding of the hazards of nano-FeOX to the organisms in other ecosystems (such as sediment) needs to be assessed to determine the overall risk of these particles to the environment.


Assuntos
Ecotoxicologia/métodos , Exposição Ambiental/análise , Compostos Férricos/análise , Modelos Estatísticos , Nanopartículas/análise , Poluentes Químicos da Água/análise , Ecotoxicologia/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , União Europeia , Compostos Férricos/química , Nanopartículas/química , Medição de Risco , Suíça , Poluentes Químicos da Água/química
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