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1.
BMC Gastroenterol ; 24(1): 153, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702642

RESUMO

BACKGROUND: Liver diseases were significant source of early readmission burden. This study aimed to evaluate the 30-day unplanned readmission rates, causes of readmissions, readmission costs, and predictors of readmission in patients with acute liver failure (ALF). METHODS: Patients admitted for ALF from 2019 National Readmission Database were enrolled. Weighted multivariable logistic regression models were applied and based on Directed Acyclic Graphs. Incidence, causes, cost, and predictors of 30-day unplanned readmissions were identified. RESULTS: A total of 3,281 patients with ALF were enrolled, of whom 600 (18.3%) were readmitted within 30 days. The mean time from discharge to early readmission was 12.6 days. The average hospital cost and charge of readmission were $19,629 and $86,228, respectively. The readmissions were mainly due to liver-related events (26.6%), followed by infection (20.9%). The predictive factors independently associated with readmissions were age, male sex (OR 1.227, 95% CI 1.023-1.472; P = 0.028), renal failure (OR 1.401, 95% CI 1.139-1.723; P = 0.001), diabetes with chronic complications (OR 1.327, 95% CI 1.053-1.672; P = 0.017), complicated hypertension (OR 1.436, 95% CI 1.111-1.857; P = 0.006), peritoneal drainage (OR 1.600, 95% CI 1.092-2.345; P = 0.016), etc. CONCLUSIONS: Patients with ALF are at relatively high risk of early readmission, which imposes a heavy medical and economic burden on society. We need to increase the emphasis placed on early readmission of patients with ALF and establish clinical strategies for their management.


Assuntos
Bases de Dados Factuais , Falência Hepática Aguda , Readmissão do Paciente , Humanos , Readmissão do Paciente/estatística & dados numéricos , Masculino , Feminino , Pessoa de Meia-Idade , Falência Hepática Aguda/economia , Falência Hepática Aguda/terapia , Fatores de Risco , Adulto , Idoso , Custos Hospitalares/estatística & dados numéricos , Fatores Sexuais , Fatores de Tempo , Modelos Logísticos , Fatores Etários , Incidência
2.
Ying Yong Sheng Tai Xue Bao ; 35(3): 749-758, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38646763

RESUMO

With the economic development, a large number of engineering accumulation bodies with Lou soil as the main soil type were produced in Guanzhong area, Northwest China. We examined the characteristics of runoff and sediment yield of Lou soil accumulation bodies with earth (gravel content 0%) and earth-rock (gravel content 30%) under different rainfall intensities (1.0, 1.5, 2.0, 2.5 mm·min-1) and different slope lengths (3, 5, 6.5, 12 m) by the simulating rainfall method. The results showed that runoff rate was relatively stable when rainfall intensity was 1.0-1.5 mm·min-1, while runoff rate fluctuated obviously when rainfall intensity was 2.0-2.5 mm·min-1. The average runoff rate varied significantly across different rainfall intensities on the same slopes, and the difference of average runoff rate of the two slopes was significantly increased with rainfall intensity. Under the same rainfall intensity, the difference in runoff rate between the slope lengths of the earth-rock slope was more obvious than that of the earth slope. When the slope length was 3-6.5 m, flow velocity increased rapidly at first and then increased slowly or tended to be stable. When the slope length was 12 m, flow velocity increased significantly. In general, with the increases of rainfall intensity, inhibition effect of gravel on the average flow velocity was enhanced. When rainfall intensity was 2.5 mm·min-1, the maximum reduction in the average flow velocity of earth-rock slope was 61.5% lower than that of earth slope. When rainfall intensity was less than 2.0 mm·min-1, sediment yield rate showed a trend of gradual decline or stable change, while that under the other rainfall intensities showed a trend of rapid decline and then fluctuated sharply. The greater the rainfall intensity, the more obvious the fluctuation. There was a significant positive correlation between the average sediment yield rate and runoff parameters, with the runoff rate showing the best fitting effect. Among the factors, slope length had the highest contribution to runoff velocity and rainfall erosion, which was 51.8% and 35.5%, respectively. This study can provide scientific basis for soil and water erosion control of engineering accumulation in Lou soil areas.


Assuntos
Sedimentos Geológicos , Chuva , Solo , Movimentos da Água , China , Solo/química , Ecossistema , Monitoramento Ambiental/métodos , Gravitação , Engenharia
3.
Public Health ; 228: 186-193, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38387115

RESUMO

OBJECTIVES: China has the largest number of hepatitis C virus (HCV) infection in the world, but current levels of diagnosis and treatment are low. The objective of this study was to assess the cost-effectiveness of various universal HCV screening and treatment strategies in China and inform decisions on health policy. STUDY DESIGN: A cost-effectiveness analytical study. METHODS: We developed a Markov model to investigate cost-effectiveness of different HCV screening and treatment strategies in China. We simulated several screening scenarios for Chinese people aged 18-70 years. We estimated incremental cost-effectiveness ratios (ICERs) of different intervention scenarios compared with status quo. RESULTS: Expanded HCV screening and treatment strategy with prioritisation for high-risk groups (Scenario S5) was the most cost-effective strategy (ICER: USD $11,667.71/quality-adjusted life-year [QALY] gained), which resulted in great reduction in HCV-related diseases and deaths, with a 67.11% reduction in cases of chronic HCV. Universal HCV screening and treatment implementation remains a cost-effective strategy when delayed until 2025 (ICER: USD $17,093.69/QALY), yet the delayed strategy is less effective in reducing HCV-related deaths. CONCLUSIONS: Expanded HCV screening and treatment strategy with prioritisation for high-risk groups is the most cost-effective strategy and has lead to a significant reduction in both HCV morbidity and mortality in China, which would essentially eliminate HCV as a public threat.


Assuntos
Hepatite C Crônica , Programas de Rastreamento , Humanos , Antivirais/uso terapêutico , China/epidemiologia , Análise Custo-Benefício , População do Leste Asiático , Hepacivirus , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/epidemiologia , Anos de Vida Ajustados por Qualidade de Vida , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso
4.
BMJ Open ; 13(6): e068944, 2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37316312

RESUMO

AIM: Distinct subtypes of Alzheimer's disease (AD) and related dementias (RD) might have different effects on dental care usage and economic burden. To determine the effects of AD and RD on specific types of dental care usage (preventive and treatment visits) and dental care costs from different payers (total and out-of-pocket costs). METHODS: A cross-sectional study was conducted using the Medicare Current Beneficiary Survey in 2016. This study identified 4268 community dwelling older adults with and without Alzheimer's disease and related dementias (ADRD) from a nationally representative sample of Medicare beneficiaries. Dental care usage and costs are based on self-reported data. Preventive dental events included preventive and diagnosis events. Treatment dental events included restorative, oral surgery and other events. RESULTS: This study identified 4268 (weighted N=30 423 885) older adults, including 94.48% without ADRD, 1.90% with AD and 3.63% with RD. Compared with older adults without ADRD, those with AD had similar dental care usage, but those with RD were 38% less likely to have treatment visit (OR: 0.62; 95% CI: 0.41 to 0.94) and had a 40% reduced number of total treatment visits (incidence rate ratio: 0.60; 95% CI: 0.37 to 0.98). RD was not associated with dental care costs, but AD was associated with higher total costs (ß: 1.08; 95% CI: 0.14 to 2.01) and higher out-of-pocket costs (ß: 1.25; 95% CI: 0.17 to 2.32). CONCLUSIONS: Patients with ADRD were more likely to have adverse dental care outcomes. Specifically, RD was associated with lower treatment dental care usage and AD was associated with higher total and out-of-pocket dental care costs. Effective patient-centred strategies should be used to improve dental care outcomes in patients with distinct subtypes of ADRD.


Assuntos
Doença de Alzheimer , Estados Unidos/epidemiologia , Humanos , Idoso , Estudos Transversais , Estresse Financeiro , Medicare , Assistência Odontológica
5.
J Clin Med ; 12(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36983235

RESUMO

Hand eczema is a common disease with economic and social ramifications. This study undertakes a review of certain existing literature to provide insight into contributory factors which may result in the varying prevalence and severity of hand eczema among different ethnic groups, particularly to identify modifiable risk factors, as well as to ascertain knowledge gaps for future research direction. The existing literature suggests that factors including (a) genes, (b) differing skin physiology, (c) cultural practices, (d) dietary habits and associated food preparation, (e) climate, (f) predominant occupations, (g) socioeconomic factors, and (h) dissimilar laws and regulations may account for the disparity in the risk of hand eczema among different ethnicities. Given that endogenous factors cannot be avoided, but certain exogenous aspects can be modified, especially as the environment plays an important role in hand eczema flares, it is helpful from a practical perspective to focus on addressing the modifiable risk factors. These factors pertain to unique cultural practices, customs, and food preparation methods. Healthcare professionals should be well-acquainted with such factors to tailor the treatment approach for patients of different ethnicities accordingly because, with globalization, physicians face increasingly diverse patient populations such that cultural customs no longer remain limited to particular geographic regions.

6.
Chin Med Sci J ; 37(3): 181-194, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36321173

RESUMO

Objective To forecast the future burden and its attributable risk factors of infective endocarditis (IE). Method We analyzed the disease burden of IE and its risk factors from 1990 to 2019 using the Global Burden of Disease 2019 database and projected the disease burden from 2020 to 2030 using a Bayesian age-period-cohort model. Results By 2030, the incidence of IE will increase uncontrollably on a global scale, with developed countries having the largest number of cases and developing countries experiencing the fastest growth. The affected population will be predominantly males, but the gender gap will narrow. The elderly in high-income countries will bear the greatest burden, with a gradual shift to middle-income countries. The incidence of IE in countries with middle/high-middle social-demographic indicators (SDI) will surpass that of high SDI countries. In China, the incidence rate and the number of IE will reach 18.07 per 100,000 and 451,596 in 2030, respectively. IE-associated deaths and heart failure will continue to impose a significant burden on society, the burden on women will increase and surpass that on men, and the elderly in high-SDI countries will bear the heaviest burden. High systolic blood pressure has become the primary risk factor for IE-related death. Conclusions This study provides comprehensive analyses of the disease burden and risk factors of IE worldwide over the next decade. The IE-associated incidence will increase in the future and the death and heart failure burden will not be appropriately controlled. Gender, age, regional, and country heterogeneity should be taken seriously to facilitate in making effective strategies for lowering the IE disease burden.


Assuntos
Endocardite , Insuficiência Cardíaca , Masculino , Humanos , Feminino , Idoso , Carga Global da Doença , Teorema de Bayes , Saúde Global , Fatores de Risco , Efeitos Psicossociais da Doença
7.
J Travel Med ; 29(3)2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35238925

RESUMO

BACKGROUND: An updated analysis of neglected tropical diseases (NTDs) from a global perspective is missing from the literature. We aimed to assess the global burden and trends of NTDs from 1990 to 2019. METHODS: Yearly incident case, mortality and disability-adjusted life years (DALYs) data for NTDs were extracted from the Global Burden of Disease Study 2019 (GBD 2019) based on global, regional, country, social development index (SDI), age and sex categories. The age-standardized rate (ASR) and number of incident cases, mortality and DALYs were computed from 1990 to 2019. The estimated annual percentage change (EAPC) in the ASR was calculated to quantify the changing trend. RESULTS: Globally, the age-standardized incidence rate (ASIR) and the number of incident cases of total NTDs increased between 1990 and 2019, whereas the age-standardized mortality rate (ASMR), mortality, age-standardized DALY rate and DALYs of total NTDs decreased. Although tropical Latin America, South Asia, Southeast Asia and Oceania had the highest ASIR for total NTDs in 2019, tropical Latin America was the only region to experience a decreasing trend in ASIR from 1673.5 per 100 000 in 2010 to 1059.2 per 100 000 in 2019. The middle, high-middle and high SDI regions experienced increasing ASIR trends between 1990 and 2019, whereas the low-middle SDI region remained stable, and the low SDI region presented a decreasing trend. Children and older adults were vulnerable to dengue, rabies and leishmaniasis (cutaneous and mucocutaneous). Females had a higher ASIR but a lower ASMR and age-standardized DALY rate than males. CONCLUSIONS: NTDs still represent a serious problem for public health, and the increasing ASIR and incident cases globally may require more targeted strategies for prevention, control and surveillance, especially among specific populations and endemic areas.


Assuntos
Carga Global da Doença , Medicina Tropical , Idoso , Criança , Feminino , Saúde Global , Humanos , Incidência , Masculino , Doenças Negligenciadas/epidemiologia , Anos de Vida Ajustados por Qualidade de Vida
8.
Front Cardiovasc Med ; 8: 721260, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34692781

RESUMO

Background and Aims: The N-terminal pro-B-type natriuretic peptide (NT-proBNP) may predict adverse cardiovascular outcomes in patients with diabetes. However, its prognostic value in patients with multivessel disease (MVD) undergoing coronary revascularization remains unclear. This study aimed to evaluate the prognostic significance of preprocedural NT-proBNP levels in diabetic patients with MVD undergoing coronary revascularization. Methods: A total of 886 consecutive diabetic patients with MVD who underwent coronary revascularization were enrolled in this study. Patients were divided into quartiles according to their pre-procedural NT-proBNP levels. Kaplan-Meier curves and Cox regression analyses were performed to evaluate the risk of cardiovascular events, including all-cause death, cardiovascular death, myocardial infarction (MI), stroke, and major adverse cardiovascular events (MACE), according to the NT-proBNP quartiles. Results: During a median follow-up period of 4.2 years, 111 patients died (with 82 being caused by cardiovascular disease), 133 had MI, 55 suffered from stroke, and 250 experienced MACE. Kaplan-Meier curves demonstrated that NT-proBNP levels were significantly associated with higher incidences of all-cause death, cardiovascular death, MI, and MACE (log-rank test, P < 0.001, respectively). Multivariate Cox regression analysis revealed that NT-proBNP level was an independent predictor of adverse outcomes, including all-cause death (HR, 1.968; 95% CI, 1.377-2.812; P < 0.001), cardiovascular death (HR, 1.940; 95% CI, 1.278-2.945; P = 0.002), MI (HR, 1.722; 95% CI, 1.247-2.380; P = 0.001), and MACE (HR, 1.356; 95% CI, 1.066-1.725; P = 0.013). The role of NT-proBNP in predicting adverse outcomes was similar in patients with stable angina pectoris and acute coronary syndrome. Moreover, preprocedural NT-proBNP alone discriminated against the SYNTAX II score for predicting all-cause death [area under the curve (AUC), 0.662 vs. 0.626, P = 0.269], cardiovascular death (AUC, 0.680 vs. 0.622, P = 0.130), MI (AUC, 0.641 vs. 0.579, P = 0.050), and MACE (AUC, 0.593 vs. 0.559, P = 0.171). The addition of NT-proBNP to the SYNTAX II score showed a significant net reclassification improvement, integrated discrimination improvement, and improved C-statistic (all P < 0.05). Conclusion: NT-proBNP levels were an independent prognostic marker for adverse outcomes in diabetic patients with MVD undergoing coronary revascularization, suggesting that preprocedural NT-proBNP measurement might help in the risk stratification of high-risk patients.

9.
Medicine (Baltimore) ; 100(31): e26862, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34397863

RESUMO

BACKGROUND: When the patients of advanced non-squamous non-small cell lung cancer (NSCLC) have achieved remission by induction therapy, it is controversial that combination with bevacizumab is used as maintenance therapy. Pemetrexed is a classic drug for maintenance therapy, is bevacizumab the superiority to pemetrexed is also unclear. This meta-analysis aims to evaluate the effectiveness and safety of advanced non-squamous NSCLC in the maintenance treatment. METHOD: From the establishment as of December 6, 2020, PubMed, Embase, and Cochrane electronic databases were searched and the American Society of Clinical Oncology, European Society of Medical Oncology, and National Comprehensive Cancer Network databases in the past 10 years. The application of combination with bevacizumab, pemetrexed was studied in clinical trials of maintenance treatment for advanced NSCLC. The extracted data include progression-free survival (PFS), overall survival (OS), and grade 3-4 adverse events (AE). RESULTS: Seven clinical trials we screened, 6 were phase III RCTs, and a cohort trial, including 3298 patients. Compared with bevacizumab and pemetrexed, PFS of combination with bevacizumab was significantly improved (hazard ratio [HR] = 0.71, 95% confidence interval [CI] = 0.65-0.77, P < .00001), but OS was not improved (HR = 0.93, 95% CI = 0.85-1.01, P = .10). Compared with bevacizumab and pemetrexed, no significant difference of PFS (HR = 0.87, 95% CI = 0.69-1.09, P = .21), and OS (HR = 0.87, 95% CI = 0.72-1.05, P = .15) was found. A higher incidence of grade 3-4 AE occurred in combination with bevacizumab (odds ratio = 1.63, 95% CI = 1.35-1.97, P < .00001). CONCLUSIONS: PFS was significantly improved in patients with advanced non-squamous NSCLC who use bevacizumab combination with single-agent as maintenance treatment, but it does not translate into the advantages of OS; compared with bevacizumab, no PFS and OS benefits were found. A higher incidence of grade 3-4 AE occurred in combination with bevacizumab than pemetrexed and bevacizumab.


Assuntos
Bevacizumab/farmacologia , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Conduta do Tratamento Medicamentoso/normas , Pemetrexede/farmacologia , Antineoplásicos Imunológicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Resultado do Tratamento
10.
Huan Jing Ke Xue ; 41(10): 4555-4563, 2020 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124387

RESUMO

Considering the Haihe River Basin as an example, the DPeRS model was used to analyze the spatial distribution characteristics and pollution sources of the diffuse pollution by remote sensing pixel scale. Combined with the evaluation standard of surface water quality, a potential risk grading method for diffuse pollution was constructed to assess the potential risk of diffuse pollution in Haihe River Basin. The results showed that, in 2016, the diffuse discharge loads of total nitrogen (TN), total phosphorus (TP), ammonia nitrogen (NH4+-N), and chemical oxygen demand (COD) were 429.2, 25.7, 288.3, and 1017.0 kg ·km-2, respectively, with the amount of river entry being 2.5×104 ton, 1597.2 ton, 1.7×104 ton, and 6.6×104 ton in Haihe River Basin, respectively. Farmland runoff is the most important source of diffuse pollution of TN, TP and NH4+-N in the Haihe River Basin. For COD index, urban life is the primary type of pollution, followed by livestock. The diffuse pollution is relatively severe in the central and southern areas of Haihe River Basin, and this area is also a high-risk concentrated distribution area of diffuse pollution in the basin. The distribution of high-risk areas of nitrogen-phosphorus diffuse pollution are relatively concentrated, and the chemical oxygen demand is relatively scattered. More than 36% of the Haihe River Basin has a nitrogen-phosphorus diffuse pollution risk, and 2.94% of the area has a chemical oxygen demand diffuse pollution risk.


Assuntos
Rios , Poluentes Químicos da Água , Análise da Demanda Biológica de Oxigênio , China , Monitoramento Ambiental , Nitrogênio/análise , Fósforo/análise , Poluentes Químicos da Água/análise
11.
J Int Med Res ; 48(8): 300060520949037, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32816562

RESUMO

OBJECTIVE: To investigate the accuracy of derecruitment volume (VDER) assessed by pressure-impedance (P-I) curves derived from electrical impedance tomography (EIT). METHODS: Six pigs with acute lung injury received decremental positive end-expiratory pressure (PEEP) from 15 to 0 in steps of 5 cmH2O. At the end of each PEEP level, the pressure-volume (P-V) curves were plotted using the low constant flow method and release maneuvers to calculate the VDER between the PEEP of setting levels and 0 cmH2O (VDER-PV). The VDER derived from P-I curves that were recorded simultaneously using EIT was the difference in impedance at the same pressure multiplied by the ratio of tidal volume and corresponding tidal impedance (VDER-PI). The regional P-I curves obtained by EIT were used to estimate VDER in the dependent and nondependent lung. RESULTS: The global lung VDER-PV and VDER-PI showed close correlations (r = 0.948, P<0.001); the mean difference was 48 mL with limits of agreement of -133 to 229 mL. Lung derecruitment extended into the whole process of decremental PEEP levels but was unevenly distributed in different lung regions. CONCLUSIONS: P-I curves derived from EIT can assess VDER and provide a promising method to estimate regional lung derecruitment at the bedside.


Assuntos
Lesão Pulmonar Aguda , Síndrome do Desconforto Respiratório , Lesão Pulmonar Aguda/diagnóstico por imagem , Animais , Impedância Elétrica , Pulmão/diagnóstico por imagem , Respiração com Pressão Positiva , Suínos , Volume de Ventilação Pulmonar , Tomografia
12.
Ecotoxicol Environ Saf ; 200: 110774, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32460055

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants in atmosphere, which attracted more attentions due to their influence on human health. In this study, a national scale cancer risk (CR) assessment with atmospheric PAHs were conducted based on one year monitoring program at 11 cities across China. The annual mean concentrations of benzo[a]pyrene (BaP) and BaP equivalency (BaPeq) were 4.56 ± 7.78 ng/m3 and 8.45 ± 14.1 ng/m3, respectively, which were both higher than the new ambient air quality standards of China (GB 3095-2012, 1 ng/m3). Concentrations of BaP and BaPeq in northern Chinese cities were almost 2 times higher than those in southern Chinese cities. The CR values induced by the dermal contact exposure were two orders of magnitude higher than that by the inhalation exposure. Children and adults were the most sensitive age groups with the dermal contact exposure and the inhalation exposure to atmospheric PAHs, respectively. For the total CR values, 99.7% of its values were higher than the reference level of 10-6. No significant difference of the total CR values was observed between northern Chinese and southern Chinese cities for children and adults. In order to quantify the uncertainties of CR assessment, Monte Carlo Simulation was applied based on the specific distributions of the exposure factors cited from the Exposure Factors Handbook of Chinese Population. The results indicated that almost 90% probability of the total CR values were higher than 10-6, indicating potential cancer risk. Sensitive analysis indicated that atmospheric concentration, outdoor exposure fraction, particle amount adhered to skin, and cancer slope factor should be carefully considered in order to increase the accuracy of CR assessment with PAHs in atmosphere.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Atmosfera/química , Monitoramento Ambiental/métodos , Exposição por Inalação/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Adolescente , Adulto , Criança , China , Cidades , Humanos , Exposição por Inalação/efeitos adversos , Método de Monte Carlo , Neoplasias/epidemiologia , Probabilidade , Medição de Risco
13.
PLoS One ; 15(2): e0227498, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32023250

RESUMO

The Yunnan-Guizhou Plateau (YGP) is a typical ecologically fragile region in southwest China. Water-erosion desertification (WED) is one of the most significant environmental and socio-economic issues on the YGP and has seriously restricted the socio-economic development of this region. However, the research on monitoring of the desertification trends in this region has been limited to long time-series Landsat imagery. The objectives of this research were to monitor the WED trends on the YGP using time-series Landsat imagery data from 1989 to 2016. In this paper, we present a multi-indicator rule-based method, which was used to map the WED on the YGP during this period. The results show that the addition of multiple indicators improved the WED classification accuracy to 90.61%. Overall, the following results were obtained by using the proposed method. (1) The slight desertification area on the YGP increased from 89,617.09 km2 in 1989 to 100,976.47 km2 in 2016 with an annual growth ratio (AGR) of 0.48%, the moderate desertification area increased from 80,276.65 km2 in 1989 to 90,768.39 km2 in 2016 with an AGR of 0.50%, and the severe desertification area increased from 8149.3 km2 in 1989 to 13,220.16 km2 in 2016 with an AGR of 2.39%. (2) The WED expansion on the YGP can be divided into three stages. Firstly, the total WED area increased slowly from 17.80×104 km2 in 1989 to 17.98×104 km2 in 2010 with an AGR of 0.05%. Then, the WED rapidly expanded from 17.98×104 km2 in 2010 to 20.28×104 km2 in 2013 with an AGR of 4.26%. Finally, the WED increased slightly from 20.28×104 km2 in 2013 to 20.50×104 km2 in 2016 with an AGR of 0.36%. The total areas of the different degrees of WED decreased in 1992, 1998, 2001, and 2004. (3) The driving factors of WED were analyzed based on the Geographically Weighted Regression (GWR) model. We found that precipitation, vegetation area, and gross domestic product have key roles in the processes of desertification reversion and development. However, the regression coefficients between WED and these factors exhibited considerable spatial variations. The regression coefficients of the key driving factors showed different spatial distributions based on the GWR model in the YGP. The research results can provide scientific reference information for the prevention and control of WED in the YGP.


Assuntos
Conservação dos Recursos Naturais , Monitoramento Ambiental , Imageamento Tridimensional , Comunicações Via Satélite , Água , China , Análise Fatorial , Geografia , Análise de Regressão , Reprodutibilidade dos Testes , Análise Espaço-Temporal , Fatores de Tempo
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117736, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31753643

RESUMO

A rapid method for detecting fatty acids (FAs) using terahertz time-domain spectroscopy (THz-TDS) technology combined with a metamaterial-based THz sensor was developed. We measured the THz responses to oleic acid, linoleic acid and α-linoleic acid with different numbers of double-bond, α-linoleic acid and γ-linoleic acid with different conformations. In addition, in order to explore the reason for the observed redshifts of the resonance frequencies of the four FAs, the dielectric constants of the FAs were measured in the THz region. Furthermore, the four fatty acids were also attempted to be identified by Raman spectroscopy, which was difficult to accomplish unambiguously because of the effect of fluorescence. This result thus demonstrates the power and usefulness of metamaterial-assisted THz-TDS in the rapid determination of the FAs, and its potential as a versatile tool for investigation of biological metabolism, and for food product quality, safety inspection and control.


Assuntos
Técnicas Biossensoriais/instrumentação , Ácidos Graxos/análise , Espectroscopia Terahertz/instrumentação , Técnicas Biossensoriais/economia , Desenho de Equipamento , Análise de Elementos Finitos , Análise de Alimentos/economia , Análise de Alimentos/instrumentação , Espectroscopia Terahertz/economia , Fatores de Tempo
15.
Infect Microbes Dis ; 2(4): 151-159, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38630095

RESUMO

A number of studies have suggested that coronavirus disease 2019 (COVID-19) can cause liver damage. However, clinical features and outcome of COVID-19 in patients with liver injury remain to be further investigated. In this study, the clinical data of 265 COVID-19 patients admitted to seven tertiary hospitals were collected. Based on a threshold for transaminase or total bilirubin levels at two times the normal upper limit, patients were divided into mild or moderate/severe liver injury groups. Among the 265 patients, 183 patients showed liver injury within 48 hours of admission. Aspartate aminotransferase levels were predominantly elevated in the liver injury group, but albumin levels were reduced. Moreover, fibrinogen and D-dimer were significantly increased. Furthermore, 68% of the patients with moderate/severe liver injury had one or more underlying diseases. Almost half of these patients developed acute respiratory distress syndrome (44%) and secondary infections (46%). These patients showed increased interleukin-6 and interleukin-10 levels and a decrease in PaO2 and the oxygenation index. In addition, levels of alanine aminotransferase, aspartate aminotransferase, and albumin were correlated with the oxygenation index, D-dimer and lymphocyte counts. Furthermore, a novel prognostic assessment model based on liver function was established, which accuracy reached 88% and was able to accurately assess the prognosis of COVID-19 patients.

16.
J Therm Biol ; 80: 16-20, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30784481

RESUMO

Inter-population variations in growth rate can result from independent or interactive effects of genetic and environmental factors, and be induced by some physiological differences as well. Toad-headed lizards (Phrynocephalus vlangalii) from a higher-elevation population were shown to have a higher growth rate than those from a lower-elevation population. The physiological basis of growth rate variation in this species is not well understood. Here, we investigated the feeding performance and resting metabolic rate (RMR) of lower- and higher-elevation individuals at different test ambient temperatures to evaluate the role of differences in energy intake, assimilation efficiency and metabolic expenditure on growth rate variations. Within the range of 25-35 °C, lizard RMR increased with increasing test ambient temperature, but food intake, apparent digestive coefficient (ADC, food energy minus faecal energy divided by food energy), and assimilation efficiency (AE, food energy minus faecal and urinary energy divided by food energy) were less thermally sensitive in both populations. Higher-elevation lizards tended to eat more food and have a lower RMR than lower-elevation ones, despite the lack of differences in ADC and AE. Our result showed that more energy intake and reduced maintenance cost may be associated with the higher growth rate of higher-elevation lizards. Accordingly, inter-population differences in energy acquisition and expenditure could act as potential sources for geographic variation in growth rate.


Assuntos
Altitude , Lagartos/fisiologia , Animais , Metabolismo Basal , Ingestão de Alimentos , Masculino
17.
J Neurosurg ; : 1-7, 2019 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-30660116

RESUMO

OBJECTIVE: The relationship between lipoprotein-associated phospholipase A2 (Lp-PLA2) and various cardiovascular and cerebrovascular diseases is inconsistent. However, the connection between Lp-PLA2 level and delayed cerebral ischemia (DCI) following aneurysmal subarachnoid hemorrhage (aSAH) remains unclear. The objective of this study was to investigate the relationships between the Lp-PLA2 levels in the early stages of aSAH and the occurrence of DCI. METHODS: The authors evaluated 114 patients with aSAH who were enrolled into a prospective observational cohort study. Serum Lp-PLA2 level at admission (D0), on the first morning (D1), and on the second morning of hospitalization (D2) were determined using commercial enzyme-linked immunosorbent assay kits. The relationship between Lp-PLA2 levels and DCI was analyzed. RESULTS: Forty-three patients with aSAH (37.72%) experienced DCI. Mean serum Lp-PLA2 level decreased from 183.06 ± 61.36 µg/L at D0 (D0 vs D1, p = 0.303), to 175.32 ± 51.49 µg/L at D1 and 167.24 ± 54.10 µg/L at D2 (D0 vs D2, p = 0.040). The Lp-PLA2 level changes (D0-D1 and D0-D2) were comparable between patients with and without DCI. Multivariate model analysis revealed Lp-PLA2 level (D0) > 200 µg/L was a more significant factor of DCI compared with Lp-PLA2 (D1) and Lp-PLA2 (D2), and was a strong predictor of DCI (odds ratio [OR] 6.24, 95% confidence interval [CI] 2.05-18.94, p = 0.001) after controlling for World Federation of Neurosurgical Societies (WFNS) grade (OR 3.35, 95% CI 1.18-9.51, p = 0.023) and modified Fisher grade (OR 6.07, 95% CI 2.03-18.14, p = 0.001). WFNS grade (area under the curve [AUC] = 0.792), modified Fisher grade (AUC = 0.731), and Lp-PLA2 level (D0; AUC = 0.710) were all strong predictors of DCI. The predictive powers of WFNS grade, modified Fisher grade, and Lp-PLA2 (D0) were comparable (WFNS grade vs Lp-PLA2: p = 0.233; modified Fisher grade vs Lp-PLA2: p = 0.771). The poor-grade patients with Lp-PLA2 (D0) > 200 µg/L had significantly worse DCI survival rate than poor-grade patients with Lp-PLA2 (D0) ≤ 200 µg/L (p < 0.001). CONCLUSIONS: The serum level of Lp-PLA2 was significantly elevated in patients with DCI, and decreased within the first 2 days after admission. Lp-PLA2 in the early stages of aSAH might be a novel predictive biomarker for the occurrence of DCI.

18.
Biochim Biophys Acta Gen Subj ; 1861(1 Pt B): 3638-3650, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27316321

RESUMO

Neutrons scatter quasielastically from stochastic, diffusive processes, such as overdamped vibrations, localized diffusion and transitions between energy minima. In biological systems, such as proteins and membranes, these relaxation processes are of considerable physical interest. We review here recent methodological advances and applications of quasielastic neutron scattering (QENS) in biology, concentrating on the role of molecular dynamics simulation in generating data with which neutron profiles can be unambiguously interpreted. We examine the use of massively-parallel computers in calculating scattering functions, and the application of Markov state modeling. The decomposition of MD-derived neutron dynamic susceptibilities is described, and the use of this in combination with NMR spectroscopy. We discuss dynamics at very long times, including approximations to the infinite time mean-square displacement and nonequilibrium aspects of single-protein dynamics. Finally, we examine how neutron scattering and MD can be combined to provide information on lipid nanodomains. This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo.


Assuntos
Biologia/métodos , Elasticidade , Cristalografia por Raios X , Hidrogênio/química , Espectroscopia de Ressonância Magnética , Cadeias de Markov , Simulação de Dinâmica Molecular , Muramidase/química , Difração de Nêutrons/métodos , Fosfoglicerato Quinase/química , Domínios Proteicos , Marcadores de Spin , Temperatura , Água/química
19.
Appl Opt ; 55(27): 7511-6, 2016 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-27661576

RESUMO

The accelerated aging tests under electric stress for one type of LED lamp are conducted, and the differences between online and offline tests of the degradation of luminous flux are studied in this paper. The transformation of the two test modes is achieved with an adjustable AC voltage stabilized power source. Experimental results show that the exponential fitting of the luminous flux degradation in online tests possesses a higher fitting degree for most lamps, and the degradation rate of the luminous flux by online tests is always lower than that by offline tests. Bayes estimation and Weibull distribution are used to calculate the failure probabilities under the accelerated voltages, and then the reliability of the lamps under rated voltage of 220 V is estimated by use of the inverse power law model. Results show that the relative error of the lifetime estimation by offline tests increases as the failure probability decreases, and it cannot be neglected when the failure probability is less than 1%. The relative errors of lifetime estimation are 7.9%, 5.8%, 4.2%, and 3.5%, at the failure probabilities of 0.1%, 1%, 5%, and 10%, respectively.

20.
Nanoscale Res Lett ; 11(1): 213, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27097913

RESUMO

Highly powered electrostatic capacitors based on nanostructures with a high aspect ratio are becoming critical for advanced energy storage technology because of their high burst power and energy storage capability. We report the fabrication process and the electrical characteristics of high capacitance density capacitors with three-dimensional solid-state nanocapacitors based on a ZnO nanowire template. Stand-up ZnO nanowires are grown face down on p-type Si substrates coated with a ZnO seed layer using a hydrothermal method. Stacks of AlZnO/Al2O3/AlZnO are then deposited sequentially on the ZnO nanowires using atomic layer deposition. The fabricated capacitor has a high capacitance density up to 92 fF/µm(2) at 1 kHz (around ten times that of the planar capacitor without nanowires) and an extremely low leakage current density of 3.4 × 10(-8) A/cm(2) at 2 V for a 5-nm Al2O3 dielectric. Additionally, the charge-discharge characteristics of the capacitor were investigated, indicating that the resistance-capacitance time constants were 550 ns for both the charging and discharging processes and the time constant was not dependent on the voltage. This reflects good power characteristics of the fabricated capacitors. Therefore, the current work provides an exciting strategy to fabricate low-cost and easily processable, high capacitance density capacitors for energy storage.

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