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1.
Angew Chem Int Ed Engl ; 57(3): 755-759, 2018 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-29193619

RESUMEN

Lanthanide (Ln) group elements have been attracting considerable attention owing to the distinct optical properties. The crystal-field surroundings of Ln ions in the host materials can determine their energy level splitting, which is of vital importance to tailor their optical properties. 2D MoS2 single crystals were utilized as the host material to embed Eu3+ and energy-level splitting was achieved for tuning its photoluminescence (PL). The high anisotropy of the 2D host materials makes them distort the degenerate orbitals of the Ln ions more efficiently than the symmetrical bulk host materials. A significant red-shift of the PL peak for Eu3+ was observed. The strategy for tailoring the energy level splitting of Ln ions by the highly designable 2D material crystal field provides a new method to extend their optical properties.

2.
J Am Chem Soc ; 138(25): 7812-5, 2016 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-27313075

RESUMEN

The challenges facing the rapid developments of highly integrated electronics, photonics, and microelectromechanical systems suggest that effective fabrication technologies are urgently needed to produce ordered structures using components with high performance potential. Inspired by the spontaneous organization of molecular units into ordered structures by noncovalent interactions, we succeed for the first time in synthesizing a two-dimensional superordered structure (2DSOS). As demonstrated by graphene, the 2DSOS was prepared via self-assembly of high-quality graphene single crystals under mutual electrostatic force between the adjacent crystals assisted by airflow-induced hydrodynamic forces at the liquid metal surface. The as-obtained 2DSOS exhibits tunable periodicity in the crystal space and outstanding uniformity in size and orientation. Moreover, the intrinsic property of each building block is preserved. With simplicity, scalability, and continuously adjustable feature size, the presented approach may open new territory for the precise assembly of 2D atomic crystals and facilitate its application in structurally derived integrated systems.

3.
Med Sci Monit ; 20: 960-6, 2014 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-24916204

RESUMEN

BACKGROUND: Pulmonary abnormalities are found in both chronic heart failure (CHF) and pulmonary arterial hypertension (PAH). The differences of pulmonary function in chronic left heart failure and chronic right heart failure are not fully understood. MATERIAL AND METHODS: We evaluated 120 patients with stable CHF (60 with chronic left heart failure and 60 with chronic right heart failure). All patients had pulmonary function testing, including pulmonary function testing at rest and incremental cardiopulmonary exercise testing (CPX). RESULTS: Patients with right heart failure had a significantly lower end-tidal partial pressure of CO2 (PetCO2), higher end-tidal partial pressure of O2 (PetO2) and minute ventilation/CO2 production (VE/VCO2) at rest. Patients with right heart failure had a lower peak PetCO2, and a higher peak dead space volume/tidal volume (VD/VT) ratio, peak PetO2, peak VE/VCO2, and VE/VCO2 slope during exercise. Patients with right heart failure had more changes in ∆PetCO2 and ∆VE/VCO2, from rest to exercise. CONCLUSIONS: Patients with right heart failure had worse pulmonary function at rest and exercise, which was due to severe ventilation/perfusion (V/Q) mismatching, severe ventilation inefficiency, and gas exchange abnormality.


Asunto(s)
Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/fisiopatología , Hipertensión Pulmonar/complicaciones , Hipertensión Pulmonar/fisiopatología , Adulto , Dióxido de Carbono/metabolismo , Enfermedad Crónica , Ejercicio Físico , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Análisis de Regresión , Pruebas de Función Respiratoria , Descanso
4.
Materials (Basel) ; 15(23)2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36500101

RESUMEN

In this paper, some progress and achievements in aircraft integrity requirements, structural health monitoring, load spectrum measurement and life assessment research were presented. Several concepts of structural health monitoring were analyzed and compared, and the basic flow chart for health monitoring and life prediction of an aircraft structure was given. The selection of control points, construction of load/strain equations and stress calculation of control points were also described. Reliable IAT (Individual Aircraft Tracking) and life monitoring methods and software for IAT were developed for a certain type of aircraft, and fatigue life prediction of an aging aircraft was conducted based on actual measurement of load spectrum. The main features such as damage calculation, life evaluation and result output were discussed, and the future research focuses relating to intelligent structural health monitoring were finally explored.

5.
Math Biosci Eng ; 19(1): 1-33, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34902978

RESUMEN

Since the outbreak of COVID-19 in Wuhan, China in December 2019, it has spread quickly and become a global pandemic. While the epidemic has been contained well in China due to unprecedented public health interventions, it is still raging or not yet been restrained in some neighboring countries. Chinese government adopted a strict policy of immigration diversion in major entry ports, and it makes Suifenhe port in Heilongjiang Province undertook more importing population. It is essential to understand how imported cases and other key factors of screening affect the epidemic rebound and its mitigation in Heilongjiang Province. Thus we proposed a time switching dynamical system to explore and mimic the disease transmission in three time stages considering importation and control. Cross validation of parameter estimations was carried out to improve the credibility of estimations by fitting the model with eight time series of cumulative numbers simultaneous. Simulation of the dynamics shows that illegal imported cases and imperfect protection in hospitals are the main reasons for the second epidemic wave, the actual border control intensities in the province are relatively effective in early stage. However, a long-term border closure may cause a paradox phenomenon such that it is much harder to restrain the epidemic. Hence it is essential to design an effective border reopening strategy for long-term border control by balancing the limited resources on hotel rooms for quarantine and hospital beds. Our results can be helpful for public health to design border control strategies to suppress COVID-19 transmission.


Asunto(s)
COVID-19 , China/epidemiología , Emigración e Inmigración , Humanos , Proyectos de Investigación , SARS-CoV-2
6.
Tob Induc Dis ; 19: 34, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33994906

RESUMEN

INTRODUCTION: Cigarette smoking has been hypothesized to be a risk factor for meningioma. However, the results of studies exploring the relationship between smoking exposure and the occurrence of meningioma are inconsistent. METHODS: A search of PubMed, Medline, Embase, and Science Direct (up to June 2020) databases was performed. Two authors independently extracted the data. The Newcastle-Ottawa Scale was employed for judging the quality of articles. A random-effects model was utilized for meta-analysis. Association analysis between smoking and meningioma was based on the adjusted RR and the 95% CI, as reported by eligible studies. Subgroup and sensitivity analyses were performed and publication bias was assessed. Subgroup analysis was conducted by geographical region, study design, sex, study quality, and adjustments of RR score. Begg's and Egger's tests were employed for detecting publication bias. RESULTS: Twelve articles, including 2 cohort studies and 10 case-control studies, and a total of 1210167 participants were identified. The pooled relative risk (RR) with 95% confidence interval (95% CI) implied that smoking was not associated with increased risk of meningioma in men and women combined (RR=1.09; 95% CI: 0.90-1.33). From the sex-stratified subgroup analysis, the risk of meningioma was significant in men (RR=1.42; 95% CI: 1.16-1.74). Risk of meningioma in women did not remain significant (RR=0.92; 95% CI: 0.73-1.16). There was a high heterogeneity in the results (I2=58.4%, p=0.002). Sensitivity analyses showed stable results and there was no evidence of publication bias. CONCLUSIONS: Cigarette smoking is not associated with a significantly increased risk of meningioma in the whole population, but there is a positive association in men but not in women.

7.
BMJ Open ; 10(4): e031953, 2020 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-32303512

RESUMEN

OBJECTIVES: This study had three objectives: (1) describe the prevalence of occupational exposure among Chinese medical personnel in detail, (2) verify the partial mediating role of work environment satisfaction in the relationship between occupational exposure and job satisfaction, and (3) examine if stress symptoms moderate the relationship between occupational exposure and job satisfaction. DESIGN: A large cross-sectional online survey was conducted in July 2018 in China. SETTING: A survey was conducted in 54 cities across 14 provinces of China. PARTICIPANTS: A total of 12 784 questionnaires were distributed, and 9924 healthcare workers (HCWs) completed valid questionnaires. The response rate was 77.63%. OUTCOME MEASURES: A confidential questionnaire was distributed to HCWs. The relationships among and the mechanisms of the variables were explored using descriptive statistical analyses, Pearson's correlation coefficient and multiple linear regression analysis. RESULTS: The most common occupational exposures among HCWs in the past 12 months were psychosocial and organisational hazards (85.93%). Overall, physicians (93.7%) and nurses (89.2%) were the main victims of occupational exposure. Occupational exposure correlated negatively with work environment satisfaction and job satisfaction, and positively with stress symptoms. Moreover, work environment satisfaction fully mediated the relationship between occupational exposure and job satisfaction, and stress symptoms moderated the relationship between occupational exposure and job satisfaction. CONCLUSION: The incidence of occupational exposure among HCWs is generally high. The high frequency of psychosocial and organisational hazards among physicians and nurses should be taken seriously and dealt with in a timely manner by hospital managers. The negative impact of occupational exposure on job satisfaction must be buffered by measures to reduce stress symptoms and enhance working environment satisfaction, ultimately improving the overall quality of life of HCWs and promoting comprehensive development of the medical team.


Asunto(s)
Satisfacción en el Trabajo , Exposición Profesional/estadística & datos numéricos , Personal de Hospital/psicología , Estrés Psicológico/epidemiología , Lugar de Trabajo/psicología , Técnicos Medios en Salud/psicología , Técnicos Medios en Salud/estadística & datos numéricos , China/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Cuerpo Médico de Hospitales/psicología , Cuerpo Médico de Hospitales/estadística & datos numéricos , Personal de Enfermería/psicología , Personal de Enfermería en Hospital/psicología , Personal de Enfermería en Hospital/estadística & datos numéricos , Exposición Profesional/efectos adversos , Personal de Hospital/estadística & datos numéricos , Farmacéuticos/psicología , Farmacéuticos/estadística & datos numéricos , Prevalencia , Análisis de Regresión , Factores de Riesgo , Encuestas y Cuestionarios/estadística & datos numéricos
8.
Int J Mol Med ; 43(2): 671-681, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30483726

RESUMEN

Myocilin is highly expressed in the trabecular meshwork (TM), which plays an important role in the regulation of intraocular pressure (IOP). Myocilin abnormalities may cause dysfunction of the TM, potentially leading to increased IOP. High IOP is a well­known primary risk factor for glaucoma. Myocilin mutations are common among glaucoma patients, and they are implicated in juvenile­onset open­angle glaucoma (JOAG) and adult­onset primary open­angle glaucoma (POAG). Aggregation of aberrant mutant myocilins is closely associated with glaucoma pathogenesis. The aim of the present review was to discuss the recent findings regarding the major physiological functions of myocilin, such as intra­ and extracellular proteolytic processes. We also aimed to discuss the risk factors associated with myocilin and the development of glaucoma, such as misfolded/mutant myocilin, imbalance of myocilin and extracellular proteins, and instability of mutant myocilin associated with temperature. Finally, we further outlined certain issues that are yet to be resolved, which may represent the basis for future studies on the role of myocilin in glaucoma.


Asunto(s)
Proteínas del Citoesqueleto/fisiología , Proteínas del Ojo/fisiología , Glaucoma de Ángulo Abierto/etiología , Glicoproteínas/fisiología , Malla Trabecular/metabolismo , Proteínas del Citoesqueleto/química , Proteínas del Citoesqueleto/genética , Proteínas del Ojo/química , Proteínas del Ojo/genética , Glaucoma de Ángulo Abierto/fisiopatología , Glicoproteínas/química , Glicoproteínas/genética , Humanos , Presión Intraocular , Mutación , Pliegue de Proteína , Proteolisis , Malla Trabecular/fisiopatología
9.
J Diabetes ; 8(2): 190-8, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25619275

RESUMEN

BACKGROUND: The aim of the present study was to estimate the incidence of type 2 diabetes (T2D) and the number of diabetes events attributable to abdominal obesity in China. METHODS: A cohort study was conducted in a sample of 24,996 Chinese adults aged 35-74 years, with 19.9% of subjects lost to follow-up. Waist circumference (WC) was measured at baseline in 1998 and 2000-01, and abdominal obesity was defined as WC ≥ 90 cm in men and ≥80 cm in women. Information on incident diabetes was collected during follow-up in 2007-08. We estimated the number of T2D events attributed to abdominal obesity using confounder-adjusted population-attributable risk, incidence of diabetes, and the population size of China in 2010. RESULTS: After a mean follow-up of 8.0 years, the age-standardized incidence of T2D was 9.6 and 9.2 per 1000 person-years in men and women, respectively. Abdominal obesity accounted for 28.1% (95% confidence interval [CI] 14.8%, 40.5%) of incident diabetes among men and 41.2% (95% CI 28.3%, 52.6%) among women using the diagnostic criteria of abdominal obesity recommended by the International Diabetes Federation. We estimated that, in 2010, 2.4 (95% CI 1.5, 3.2) million diabetes events were attributable to abdominal obesity: 1.0 (95% CI 0.5, 1.4) million in men and 1.4 (95% CI 1.0, 1.8) million in women. CONCLUSIONS: Abdominal obesity is a major risk factor for T2D. Strengthening programs and initiatives for preventing and controlling obesity focusing on lifestyle changes should be a priority in the national strategy to reduce diabetes burden in China.


Asunto(s)
Pueblo Asiatico/estadística & datos numéricos , Diabetes Mellitus Tipo 2/epidemiología , Obesidad Abdominal/epidemiología , Adulto , Anciano , China/epidemiología , Estudios de Cohortes , Comorbilidad , Diabetes Mellitus Tipo 2/etnología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Análisis Multivariante , Obesidad Abdominal/etnología , Modelos de Riesgos Proporcionales , Medición de Riesgo/métodos , Medición de Riesgo/estadística & datos numéricos , Factores de Riesgo , Circunferencia de la Cintura
10.
Diabetes Res Clin Pract ; 107(3): 424-32, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25649908

RESUMEN

AIMS: To estimate the incidence of Type 2 diabetes mellitus (T2DM) and the number of those with T2DM attributable to overweight and obesity in China. METHODS: We conducted a prospective cohort study among 15680 participants (46.4%, men) aged 35-74 years. The mean duration of follow-up was 8.0 years. We examined the relationship between overweight, obesity and risk of T2DM by Cox proportional hazards models. Population attributable risk (PAR) of overweight and obesity was also calculated. Moreover, we estimated the number of T2DM events attributed to overweight and obesity using PAR, incidence of T2DM and the population size of China in 2010. RESULTS: During a mean follow-up of 8.0 years, the age-standardized incidence of T2DM was 9.5 per 1000 person-years in men and 9.2 in women. Overweight accounted for 28.3% (95% confidence interval [CI]: 20.1, 36.2) of incident T2DM among men and 31.3% (95% CI: 25.5, 36.9) among women. The corresponding PAR of obesity was 10.1% (95% CI: 6.0, 14.2) among men and 16.8% (95% CI: 12.0, 21.6) among women. Approximately 3.32 million (95% CI: 2.47, 4.24) incident T2DM were attributable to overweight and obesity in Chinese adults who were 35 to 74 years in 2010. CONCLUSION: Our results indicate that incident T2DM is mainly attributable to overweight and obesity in China. It is extremely important to advocate healthy lifestyle and prevent excessive weight gain for reducing T2DM burden in China.


Asunto(s)
Diabetes Mellitus Tipo 2/epidemiología , Obesidad/epidemiología , Sobrepeso/epidemiología , Adulto , Anciano , Pueblo Asiatico/estadística & datos numéricos , Índice de Masa Corporal , China/epidemiología , Estudios de Cohortes , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Sobrepeso/complicaciones , Estudios Prospectivos , Factores de Riesgo
11.
J Womens Health (Larchmt) ; 23(5): 373-81, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24611563

RESUMEN

BACKGROUND: Alcoholic beverages are consumed by humans for a variety of dietary, recreational, and other reasons. It is uncertain whether the drinking effect on risk of all-cause mortality is different between women and men. We conducted a meta-analysis to evaluate the effect of drinking on the risk of all-cause mortality in women compared with men. METHODS: We selected cohort studies with measures of relative risk (RR) and 95% confidence interval (CI) for all-cause mortality for drinkers versus nondrinkers by sex. Sex-specific RR and 95% CI were used to estimate the female-to-male ratio of RR (RRR) and 95% CI. Pooled estimates of RRR across studies were obtained by the fixed-effects model or the random-effects model (if heterogeneity was detected). Second-order fractional polynomials and random effects meta-regression models were used for modeling the dose-risk relationship. RESULTS: Twenty-four studies were considered eligible. A total of 2,424,964 participants (male: 1,473,899; female: 951,065) were enrolled and 123,878 deaths (male: 76,362; female: 47,516) were observed. Compared with nondrinkers, the pooled female-to-male RRR for drinkers was 1.07 (95% CI: 1.02, 1.12). Subgroup analyses showed that the increased risk among female drinkers appeared to be consistent. J-shaped dose-response relationship was confirmed between alcohol and all-cause mortality in men and women, respectively. Moreover, the female-to-male RRR of all-cause mortality were 1.52 (95% CI: 1.01, 2.29), 1.95 (95% CI: 1.08, 3.49), and 2.36 (95% CI: 1.15, 4.88), respectively, for those who consumed 75, 90, and 100 g/day of alcohol. CONCLUSIONS: Females had an increased risk for all-cause mortality conferred by drinking compared with males, especially in heavy drinkers. The present study suggested that female drinkers, particularly heavy drinkers, should moderate or completely reduce their level of consumption to have a health benefit.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/mortalidad , Adulto , Factores de Edad , Anciano , Análisis de Varianza , Intervalos de Confianza , Femenino , Humanos , Masculino , Estudios Prospectivos , Factores de Riesgo , Factores Sexuales , Adulto Joven
12.
Zhonghua Liu Xing Bing Xue Za Zhi ; 30(12): 1252-7, 2009 Dec.
Artículo en Zh | MEDLINE | ID: mdl-20193308

RESUMEN

OBJECTIVE: To understand the incidence rates of agricultural profession-related injuries and the relationship to alcohol consumption. METHODS: A multistage sample of 2366 villagers was selected from Minority Nationality Villages, Heilongjiang province. Face-to-face interviews were conducted by trained interviewers during May 2008. 2198 (92.9%) of the eligible questionnaires were available. RESULTS: Incidence rate of agricultural profession-related injury rate was 11.8% (260/2198) from May 2007 to April 2008. Higher proportions of injuries were seen for males, 30 - 49 year olds, farmers and among those people working on farms for 10 years or more, smoking during farm work, with sleeping disorder, using motor vehicles, and those using agricultural machinery. Rate of alcohol drinking was 29.1% (640/2198) in the month prior to the investigation. Results from logistic regression models showed that alcohol consumption patterns and other alcohol-related behavior were examined in separate logistic models because of collinearity by controlling the variables that were associated with agricultural profession-related injury including sex, age, years of farm work, driving a motor vehicle, and agricultural machinery use etc. In each model, the reference group was those villagers who did not drink in the past month. The odds of injury among villagers with history of past month drinking, who drank distilled spirits, and alcohol drinking at breakfast and lunch were 1.80 (95%CI: 1.24 - 2.62), 2.09 (95%CI: 1.38 - 3.15), 2.15(95%CI: 1.43 - 3.22) respectively. The odds of agricultural injury also significantly increased with greater average amounts of pure alcohol per day, with increased frequency of drinking per week, and reported years of drinking. CONCLUSION: Intervention efforts should include increasing awareness about alcohol drinking as a major risk factor causing agricultural injuries as well as controlling alcohol drinking, improving knowledge about driving motor vehicle and using agricultural machinery.


Asunto(s)
Accidentes de Trabajo/estadística & datos numéricos , Agricultura , Consumo de Bebidas Alcohólicas/epidemiología , Adulto , Intoxicación Alcohólica/epidemiología , China/epidemiología , Femenino , Humanos , Incidencia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Grupos Minoritarios , Factores de Riesgo , Población Rural , Encuestas y Cuestionarios
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