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1.
Environ Sci Technol ; 55(10): 6665-6676, 2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-33960763

RESUMEN

Gaseous sulfuric acid (H2SO4) is a crucial precursor for secondary aerosol formation, particularly for new particle formation (NPF) that plays an essential role in the global number budget of aerosol particles and cloud condensation nuclei. Due to technology challenges, global-wide and long-term measurements of gaseous H2SO4 are currently very challenging. Empirical proxies for H2SO4 have been derived mainly based on short-term intensive campaigns. In this work, we performed comprehensive measurements of H2SO4 and related parameters in the polluted Yangtze River Delta in East China during four seasons and developed a physical proxy based on the budget analysis of gaseous H2SO4. Besides the photo-oxidation of SO2, we found that primary emissions can contribute considerably, particularly at night. Dry deposition has the potential to be a non-negligible sink, in addition to condensation onto particle surfaces. Compared with the empirical proxies, the newly developed physical proxy demonstrates extraordinary stability in all the seasons and has the potential to be widely used to improve the understanding of global NPF fundamentally.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente , Tamaño de la Partícula , Material Particulado/análisis , Ríos , Ácidos Sulfúricos
2.
Arch Gerontol Geriatr ; 127: 105558, 2024 12.
Artículo en Inglés | MEDLINE | ID: mdl-39018968

RESUMEN

BACKGROUND: The fractures of patients with osteoporosis represent a major health care burden that requires efficient prevention. OBJECTIVE: To analyze the efficacy and significance of diverse interventions for preventing falls or fractures in patients with osteoporosis, and to establish a foundation for clinical interventions. METHODS: Ten databases were searched for studies published before January 30, 2024. Screening, data extraction, and risk of bias assessment were independently conducted by two researchers using Stata 14.0 software. A network meta-analysis using the frequentist framework was then performed to determine the effectiveness of various interventions for preventing and managing falls and fractures in patients with osteoporosis. The findings were used as basis for the prioritization of interventions. RESULTS: The initial search yielded 3894 studies. After 3878 studies were excluded, 16 studies were finally included. For the prevention of falls in patients with osteoporosis, effective interventions include exercise and exercise plus medication. A combination of exercise, assessment and modifications, quality improvement strategies, social engagement, basic falls risk assessment, and assistive technology may be the preferred recommended intervention. For the prevention of fractures in patients with osteoporosis, no statistically significant disparities were observed among the compared interventions, exercise may be the preferred recommended intervention. CONCLUSION: Exercise and exercise plus medication are effective in reducing the number of falls in patients with osteoporosis. Although exercise may be the optimal intervention for fracture prevention, the quality of current evidence remains inadequate. Large-scale high-quality randomized controlled trials are necessary to substantiate these findings. TRIAL REGISTRATION: PROSPERO CRD42024507487.


Asunto(s)
Accidentes por Caídas , Metaanálisis en Red , Osteoporosis , Anciano , Humanos , Accidentes por Caídas/prevención & control , Accidentes por Caídas/estadística & datos numéricos , Terapia por Ejercicio/métodos , Osteoporosis/complicaciones , Osteoporosis/prevención & control , Fracturas Osteoporóticas/prevención & control , Medición de Riesgo
3.
Sci Total Environ ; 917: 170373, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38286297

RESUMEN

Peroxyacetyl nitrate (PAN) is a significant indicator of atmospheric photochemical pollution, which can influence the regional distribution of ozone (O3) and hydroxyl radical (OH) through long-range transport. However, investigations of PAN incorporating comprehensive measurement and explicit modeling analysis are limited, hindering complete understandings of its temporal behavior, sources, and impacts on photochemistry. Here we conducted a 1-year continuous observation of PAN and relative atmospheric species in Nanjing located in Yangtze River Delta (YRD). The annual mean concentration of PAN was 0.62 ± 0.49 ppbv and showed a bimodal monthly variation, peaking in April-June and November-January, respectively. This pattern is different from the typical pattern of photochemistry, suggesting important contributions of other non-photochemical processes. We further analyzed the PAN budget using an observation-based model, by which, PAN from local photochemical production and regional source could be decoupled. Our results revealed that local photochemical production of PAN is the sole contributor to PAN in summer, whereas about half of the total PAN concentration is attributed to regional source in winter. Although the formation of PAN can suppress the atmospheric oxidation capacity by consuming the peroxyacetyl radical and nitrogen dioxide (NO2), our analyses suggested this effect is minor at our station (-3.2 ± 1.1 % in summer and - 7.2 ± 2.8 % in winter for O3 formation). However, it has the potential to enhance O3 and OH formation by 14.16 % and 5.93 %, if transported to cleaner environments with air pollutants halved. Overall, our study highlights the importance of both local photochemistry and regional process in PAN budget and provides a useful evaluation on the impact of PAN on atmospheric oxidation capacity.

4.
Bioact Mater ; 6(8): 2569-2612, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33615045

RESUMEN

Metals and alloys, including stainless steel, titanium and its alloys, cobalt alloys, and other metals and alloys have been widely used clinically as implant materials, but implant-related infection or inflammation is still one of the main causes of implantation failure. The bacterial infection or inflammation that seriously threatens human health has already become a worldwide complaint. Antibacterial metals and alloys recently have attracted wide attention for their long-term stable antibacterial ability, good mechanical properties and good biocompatibility in vitro and in vivo. In this review, common antibacterial alloying elements, antibacterial standards and testing methods were introduced. Recent developments in the design and manufacturing of antibacterial metal alloys containing various antibacterial agents were described in detail, including antibacterial stainless steel, antibacterial titanium alloy, antibacterial zinc and alloy, antibacterial magnesium and alloy, antibacterial cobalt alloy, and other antibacterial metals and alloys. Researches on the antibacterial properties, mechanical properties, corrosion resistance and biocompatibility of antibacterial metals and alloys have been summarized in detail for the first time. It is hoped that this review could help researchers understand the development of antibacterial alloys in a timely manner, thereby could promote the development of antibacterial metal alloys and the clinical application.

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