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1.
Water Res ; 257: 121693, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38728785

RESUMO

Cyanobacterial harmful algal blooms (cyanoHABs) are becoming increasingly common in aquatic ecosystems worldwide. However, their heterogeneous distributions make it difficult to accurately estimate the total algae biomass and forecast the occurrence of surface cyanoHABs by using traditional monitoring methods. Although various optical instruments and remote sensing methods have been employed to monitor the dynamics of cyanoHABs at the water surface (i.e., bloom area, chlorophyll a), there is no effective in-situ methodology to monitor the dynamic change of cell density and integrated biovolume of algae throughout the water column. In this study, we propose a quantitative protocol for simultaneously measurements of multiple indicators (i.e., biovolume concentration, size distribution, cell density, and column-integrated biovolume) of cyanoHABs in water bodies by using the laser in-situ scattering and transmissometry (LISST) instrument. The accuracy of measurements of the biovolume and colony size of algae was evaluated and exceeded 95% when the water bloom was dominated by cyanobacteria. Furthermore, the cell density of cyanobacteria was well estimated based on total biovolume and mean cell volume measured by the instrument. Therefore, this methodology has the potential to be used for broader applications, not only to monitor the spatial and temporal distribution of algal biovolume concentration but also monitor the vertical distribution of cell density, biomass and their relationship with size distribution patterns. This provides new technical means for the monitoring and analysis of algae migration and early warning of the formation of cyanoHABs in lakes and reservoirs.


Assuntos
Cianobactérias , Monitoramento Ambiental , Monitoramento Ambiental/métodos , Proliferação Nociva de Algas , Biomassa , Eutrofização , Clorofila/análise
2.
Artigo em Inglês | MEDLINE | ID: mdl-36768070

RESUMO

Improving urban land green use efficiency (ULGUE) is an effective way to increase social, economic, and ecological benefits and achieve regional sustainable development goals. This study takes three batches of low-carbon pilot cities construction as a quasi-natural experiment and investigates the impact of low-carbon pilot construction on ULGUE through the multi-period difference-in-differences method and spatial Dubin difference model (SDM-DID). The results show that (1) from 2006 to 2019, ULGUE in China increased. From the aspect of space, ULGUE in China gradually decreased from west to east, showing an obviously high agglomeration phenomenon in Beijing-Tianjin-Hebei and the Pearl River Delta; (2) after the robustness test, parallel trend test, and endogenous test, it is found that the conclusion that the low-carbon pilot construction can effectively improve ULGUE is still relevant and can indirectly improve ULGUE in the local region through fund allocation, talent gathering, and industrialization; and (3) the national ULGUE has significant positive spatial correlation. The results of the SDM-DID model confirm that the low-carbon pilot policy can produce the significant spatial spillover and drive the common advance of ULGUE in neighboring regions. Therefore, the resources and environmental conditions in each city are supposed to be taken into full consideration theoretically. Furthermore, it is necessary to effectively promote the development of ULGUE by strengthening the linkage of green production factors between different cities, so as to make meaningful contributions to promoting China's overall green development.


Assuntos
Carbono , Urbanização , Cidades , Pequim , China , Desenvolvimento Sustentável , Desenvolvimento Econômico
3.
BMC Public Health ; 22(1): 2450, 2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-36577998

RESUMO

BACKGROUND: People's health belief is an important factor affecting health behavior. However, there has been little use of the health belief model (HBM) in determining the pathway effect of patients' beliefs on health behavior in dementia prevention in China. The aim of our study was to evaluate the impact of dementia prevention beliefs on health promoting lifestyle among Chinese adults. METHODS: A cross-sectional study was conducted on line by convenience sampling from January to March 2020. A survey about dementia prevention knowledge, health belief of dementia prevention and health-promoting lifestyle was completed by 1201 adults in China. Data was analyzed using a structural equation model with the analysis of moment program. RESULTS: The participants were aged 40.50 ± 12.72 years. About 70.3% of participants were female. The purposed model fit the data from the study well. Perceived barriers (total effect-0.322, P < 0.01) and perceived susceptibility (total effect -0.242, P < 0.01) had negative effects on lifestyle. Self-efficacy had promoting effects on lifestyle (total effect 0.207, P < 0.01). Perceived severity had positive effects both on perceived benefits (total effect 0.137, P < 0.01) and perceived barriers (total effect 0.202, P < 0.01), which had a contradictory effect in the formation of health belief. Perceived benefits, cues to action and self-efficacy played a partial mediating role between knowledge and health behavior. The belief of changing lifestyle to reduce the risk of dementia could explain 24.5% of health behavior (P < 0.05). CONCLUSIONS: The findings indicate that in dementia prevention, dementia prevention health belief has important influences on health behavior. Community medical staff can develop targeted dementia prevention interventions based on the health belief model in the future.


Assuntos
Demência , População do Leste Asiático , Humanos , Adulto , Feminino , Masculino , Estudos Transversais , Estilo de Vida , Modelo de Crenças de Saúde , Inquéritos e Questionários , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde , Demência/epidemiologia , Demência/prevenção & controle
4.
Artigo em Inglês | MEDLINE | ID: mdl-35509627

RESUMO

Background: Tai Chi (TC) exercise has recently received wide attention for its efficacy in the management of cognitive impairment. The purpose of this overview is to summarize the available evidence on TC treatment of cognitive impairment and assess its quality. Methods: We retrieved relevant systematic reviews/meta-analyses (SRs/MAs) from 7 databases from the time they were established to January 2, 2022. Two reviewers independently evaluated the methodological quality, risk of bias, report quality, and evidence quality of the included SRs/MAs on randomized controlled trials (RCTs). The tools used are Assessment System for Evaluating Methodological Quality 2 (AMSTAR-2), the Risk of Bias In Systematic (ROBIS) scale, the list of Preferred Reporting Items for Systematic Reviews And Meta-Analysis (PRISMA), and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Results: This overview finally included 8 SRs/MAs. According to the results of AMSTAR-2, all included SRs/MAs were rated as very low quality. Based on the ROBIS tool, none of the SR/MA had a low risk of bias. In light of PRISMA, all SRs/MAs had reporting deficiencies. According to the GRADE system, there was only 1 high-quality piece of evidence. Conclusion: TC is a promising complementary and alternative therapy for cognitive impairment with high safety profile. However, in view of the low quality of the included SRs/MAs supporting this conclusion, high-quality evidence with a more rigorous study design and a larger sample size is needed before making a recommendation for guidance.

5.
Waste Manag ; 48: 652-660, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26589868

RESUMO

Compared with United States of America (USA), Brazil, Chile, Australia, limited attention has been paid to marine debris research in China and few studies have attempted to quantify the abundance and mass of marine debris. In this study, firstly the general status and sources of marine debris in China were assessed in the time period between 2007 and 2014, and secondly marine debris situation was evaluated in three China Sea Areas (the North China Sea, the East China Sea and the South China Sea) from 2009 to 2013, and finally marine debris conditions and sources were analyzed in beaches or seawaters around some coastal provinces of China during 2007-2013. Based on above analysis, the primary conclusions were as follows: (1) The mean number and weight densities of beached marine debris (BMD) and submerged marine debris (SMD) were 4.30, 0.13items/100m(2) and 133.80, 22.60g/100m(2) in China from 2007 to 2014, respectively. The average number density of the large size FMD (LOSFMD) was 0.0024items/100m(2) and that of the small and medium size FMD (SMSFMD) was 0.30items/100m(2), and the mean weight density of the SMSFMD was 1.40g/100m(2) from 2008 to 2014. The SMD and FMD densities were at the low level and the BMD density was at the high level in China. (2) The marine debris primarily was comprised of plastic, Styrofoam, wood, glass, rubber, fabric/fiber and metal, which included almost all major categories of marine debris. (3) Sources of BMD and FMD were as follows: the first source was coastal/recreational activities, followed by other disposal sources, navigation/fishing activities and the activities related smoking, and the least source being those associated with medical/sanitary activities, while the source of SMD remained unknown. (4) The mean number and weight densities of BMD were the biggest in the North China Sea, while those of FMD and SMD were the highest in the northern South China Sea. The results of this study were beneficial to the establishment of management measures for dealing with ecological and environmental problems that were generated by the high speed socio-economic development in China.


Assuntos
Resíduos/análise , China , Ecologia , Meio Ambiente , Monitoramento Ambiental/métodos , Geografia , Oceanos e Mares , Plásticos/análise , Poliestirenos , Eliminação de Resíduos , Água do Mar , Poluentes da Água/análise , Poluição da Água/análise , Madeira/química
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