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1.
Risk Manag Healthc Policy ; 17: 65-77, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38204928

RESUMEN

Background: The Healthy China 2030 (HC2030) policy is currently recognized as China's most significant and influential national health policy. However, despite its implementation in 2016, the policy's impact has yet to be comprehensively evaluated, particularly in relation to its effectiveness in enhancing population health and promoting public health equity. Methods: We utilized the Difference-in-Differences (DiD) method to evaluate the impact of the HC2030. Our analysis utilized a panel dataset derived from five longitudinal surveys conducted by the China Family Panel Studies (CFPS). Results: The implementation of HC2030 has improved the overall health status of residents, particularly in urban areas and the western and eastern regions. Mechanistic analysis has further unveiled that the policy's beneficial impact on health outcomes is attributed to a rise in physical activity frequency and the betterment of mental health. Additionally, female, married, and medically insured individuals have demonstrated a significant positive impact of the policy on their health outcomes. Conclusion: Although the HC2030 appears to have effectively improved overall population health, it needs to promote equity in public health adequately. The study suggests adjustments are needed to address the unequal distribution of health outcomes between urban and rural areas and among different regions.

2.
Nanoscale ; 15(45): 18233-18240, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37943087

RESUMEN

Achieving self-powered photodetection without biasing is a notable challenge for photodetectors. In this work, we demonstrate the successful fabrication of large-scale van der Waals epitaxial molybdenum disulfide (MoS2) on a p-GaN/sapphire substrate using a straightforward chemical vapor deposition (CVD) technique. Our research primarily centers on the characterization of these photodetectors produced through this method. The MoS2/GaN heterojunction photodetector showcases a broad and extensive photoresponse spanning from ultraviolet A (UVA) to near-infrared (NIR). When illuminated by a 532 nm laser, its self-powered photoresponse is characterized by a rise time (τr) of ∼18.5 ms and a decay time (τd) of ∼123.2 ms. The photodetector achieves a responsivity (R) of ∼0.13 A W-1 and a specific detectivity (D*) of ∼3.8 × 1010 Jones at zero bias. Additionally, while utilizing a 404 nm laser, the photodetector reaches a maximum R and D* of ∼1.7 × 104 A/W and ∼1.6 × 1013 Jones, respectively, at Vb = 5 V. The operational mechanism of the device can be explained by the diode characteristics involving a tunneling current in the presence of reverse bias. The exceptional performance of these photodetectors can be attributed to the pristine interface between the CVD-grown MoS2 and GaN, providing an impeccably clean tunneling surface. Additionally, our investigation has unveiled that MoS2/GaN heterostructure photodetectors, featuring MoS2 coverage percentages spanning from 20% to 50%, exhibit improved responsivity capabilities at an external bias voltage. As a result, this facile CVD growth technique for MoS2 photodetectors holds significant potential for large-scale production in the manufacturing industry.

3.
Int J Mol Sci ; 23(16)2022 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-36012548

RESUMEN

Chitosan-based composite films with good biodegradability, biocompatibility, and sustainability are extensively employed in the field of food packaging. In this study, novel chitosan/tannic acid (CTA) and chitosan/oxidized tannic acid (COTA) composite films with excellent mechanical and antibacterial properties were prepared using a tape casting method. The results showed that, when 20% tannic acid (TA) was added, the tensile strength of the CTA composite film was 80.7 MPa, which was 89.4% higher than that of the pure chitosan (CS) film. TA was oxidized to oxidized tannic acid (OTA) with laccase, and the phenolic hydroxyl groups were oxidized to an o-quinone structure. With the addition of OTA, a Schiff base reaction between the OTA and CS occurred, and a dual network structure consisting of a chemical bond and hydrogen bond was constructed, which further improved the mechanical properties. The tensile strength of 3% COTA composite film was increased by 97.2% compared to that of pure CS film. Furthermore, these CTA films with significant antibacterial effects against Escherichia coli (E. coli) are likely to find uses in food packaging applications.


Asunto(s)
Quitosano , Antibacterianos/química , Antibacterianos/farmacología , Quitosano/química , Escherichia coli , Embalaje de Alimentos/métodos , Enlace de Hidrógeno , Bases de Schiff/farmacología , Taninos/química , Resistencia a la Tracción
4.
Environ Pollut ; 255(Pt 1): 113133, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31536879

RESUMEN

As a new type of emerging pollutant in the ocean, microplastics have received global attention in recent years. Considering the increasing amount of human activities around the South China Sea, it is important to determine the current status of microplastic pollution in this region. In this study, we analyzed the abundance and distribution of microplastics at Zhubi Reef in the South China Sea. Microplastic abundance ranged from 1400 to 8100 items/m3 of surface water, which was much higher than the values reported from other ocean areas. About 80% of the microplastics were smaller than 0.5 mm in size. Fibers and pellets comprised the most common microplastic types. The dominant microplastics were transparent or blue in color. The main polymer types were polypropylene (25%) and polyamide (18%). In general, our results revealed Zhubi Reef was contaminated with microplastics, which were likely derived from the intensive fisheries in the area and emissions from coastal cities. This study also provides baseline data that are useful for additional studies of microplastics in the South China Sea.


Asunto(s)
Monitoreo del Ambiente/métodos , Microplásticos/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/análisis , China , Ciudades , Arrecifes de Coral , Nylons/análisis , Polipropilenos/análisis
5.
Sci Total Environ ; 696: 134022, 2019 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-31470325

RESUMEN

Nanxun Reef is one of the typical reefs in Nansha Islands, South China Sea. As the Nansha Islands are surrounded by certain developing countries, the economic and population growth have resulted in increased surface runoff of persistent organic pollutants in offshore areas. Microplastic has been found in many freshwaters and sea areas in recent years. However, the levels of microplastics contamination in Nansha Islands are still uncharted. In this study, 15 water and 35 fish samples were collected around the Nanxun Reef. The average concentration of microplastics was 1733 items/m3 for surface water samples and 3.1 items per individual for fish samples. The majority of ingested microplastics by fish were fibers, mostly transparent or blue. In surface water samples, blue microbeads were the main types of microplastics, accounting for 76.5% of all the detected particles. The main size of microplastics was <0.5 mm both in water and fish samples. Our results demonstrated that fishery activities and human domestic sewage might be the dominant sources of microplastic pollution in the Nansha Island, South China Sea.


Asunto(s)
Monitoreo del Ambiente , Peces/metabolismo , Microplásticos/análisis , Contaminantes Químicos del Agua/análisis , Animales , China , Arrecifes de Coral , Islas , Microplásticos/metabolismo , Contaminantes Químicos del Agua/metabolismo
6.
Fish Shellfish Immunol ; 84: 130-137, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30278220

RESUMEN

Intestinal microbiota homeostasis is crucial to the health of host. Pathogen invasion results in dynamics of microbiota composition and structure, disrupting their function in maintaining host health. WSSV is the most prevalent viral pathogen and is able to cause extremely high mortality in Litopenaeus vannamei. However, the changes of intestinal microbiota induced by WSSV are yet to be elucidated. In this study, we analyzed and compared the microbiota of healthy and WSSV-challenged shrimp intestines. Though the richness and diversity of microbiota was barely affected by WSSV, the abundance of predominant phyla like Proteobacteria and Fusobacteria were upregulated significantly, while Bacteroidetes and Tenericutes were significantly decreased in WSSV-infected shrimps. At the genus level, significant increase was observed in Photobacterium, Propionigenium and Arcobacter, as well as significant decrease in Candidatus Bacilloplasma and Flavobacterium in WSSV-infected shrimps. Additionally, metagenomic predictions by PICRUSt suggested that the altered microbiota was mainly related to metabolism, human diseases, genetic information processing, environmental information processing and cellular processes. These results suggested that the invasion of WSSV could impact intestinal microbiota composition and function in L. vannamei.


Asunto(s)
Infecciones por Virus ADN/microbiología , Microbioma Gastrointestinal , Penaeidae/microbiología , Virus del Síndrome de la Mancha Blanca 1 , Animales , Bacterias/genética , Bacterias/aislamiento & purificación , Infecciones por Virus ADN/veterinaria , ADN Bacteriano/genética , ARN Ribosómico 16S/genética
7.
IEEE J Biomed Health Inform ; 23(4): 1639-1646, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30176612

RESUMEN

While myoelectric pattern recognition is a prevailing way for gesture recognition, the inherent nonstationarity of electromyography signals hinders its long-term application. This study aims to prove a hypothesis that morphological information of muscle contraction detected by ultrasound image is potentially suitable for long-term use. A set of ultrasound-based algorithms are proposed to realize robust hand gesture recognition over multiple days, with user training only at the first day. A markerless calibration algorithm is first presented to position the ultrasound probe during donning and doffing; an algorithm combining speeded-up robust features and bag-of-features model being immune to ultrasound probe shift and rotation is then introduced; a self-enhancing classification method is next adopted to update classification model automatically by incorporating useful knowledge from testing data; finally the performance of long-term hand gesture recognition with zero re-training is validated by a six-day experiment of six healthy subjects, whose outcomes strongly support the hypothesis with about 94% of gesture recognition accuracy for each testing day. This study confirms the feasibility of adoption of ultrasound sensing for long-term musculature related applications.


Asunto(s)
Gestos , Mano/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Ultrasonografía/métodos , Adulto , Algoritmos , Mano/fisiología , Humanos , Masculino , Contracción Muscular/fisiología , Adulto Joven
8.
IEEE J Biomed Health Inform ; 22(5): 1395-1405, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29990031

RESUMEN

Motions of the fingers are complex since hand grasping and manipulation are conducted by spatial and temporal coordination of forearm muscles and tendons. The dominant methods based on surface electromyography (sEMG) could not offer satisfactory solutions for finger motion classification due to its inherent nature of measuring the electrical activity of motor units at the skin's surface. In order to recognize morphological changes of forearm muscles for accurate hand motion prediction, ultrasound imaging is employed to investigate the feasibility of detecting mechanical deformation of deep muscle compartments in potential clinical applications. In this study, finger motion classification has been represented as subproblems: recognizing the discrete finger motions and predicting the continuous finger angles. Predefined 14 finger motions are presented in both sEMG signals and ultrasound images and captured simultaneously. Linear discriminant analysis classifier shows the ultrasound has better average accuracy (95.88%) than the sEMG (90.14%). On the other hand, the study of predicting the metacarpophalangeal (MCP) joint angle of each finger in nonperiod movements also confirms that classification method based on ultrasound achieves better results (average correlation 0.89 $\pm$ 0.07 and NRMSE 0.15 $\pm$ 0.05) than sEMG (0.81 $\pm$ 0.09 and 0.19 $\pm$ 0.05). The research outcomes evidently demonstrate that the ultrasound can be a feasible solution for muscle-driven machine interface, such as accurate finger motion control of prostheses and wearable robotic devices.


Asunto(s)
Electromiografía/métodos , Dedos/fisiología , Movimiento/fisiología , Procesamiento de Señales Asistido por Computador , Ultrasonografía/métodos , Adulto , Análisis Discriminante , Humanos , Masculino , Interfaz Usuario-Computador , Adulto Joven
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