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1.
BMC Public Health ; 24(1): 1193, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38679720

RESUMO

BACKGROUND: Residents' adoption of preventive behaviours proved beneficial in preventing the large-scale transmission of the virus during the early stages of the COVID-19 outbreak. It is critical to investigate how social media triggers residents' preventive behaviour decisions during the COVID-19 outbreak. METHODS: This paper selected online shopping as a specific preventive behaviour for empirical investigation. An online cross-sectional survey was conducted through the Sojump website from 1 to 15 March 2020, and a total of 1,289 valid questionnaires were collected from China. This paper uses multiple regression analysis to investigate the heterogeneous impacts of different information sources on residents' online shopping willingness and online shopping behaviour and the heterogeneous impacts of different information content in social media on the transformation of residents' online shopping willingness and online shopping behaviour. RESULTS: The findings indicate that both official-media and self-media positively promote residents' online shopping willingness and behaviour, with official-media having a stronger promotional effect than self-media. Furthermore, official-media and self-media can collaboratively promote residents' online shopping willingness and online shopping behaviour. The ease-of-use and usefulness of information significantly promoted the transformation of residents' online shopping willingness. CONCLUSIONS: This study analyses the heterogeneous impacts of social media on residents' preventive behaviours from the perspectives of information source differentiation and information content differentiation, which enriches related studies and provides feasible paths for promoting residents' preventive behaviours.


Assuntos
COVID-19 , Mídias Sociais , Humanos , Mídias Sociais/estatística & dados numéricos , COVID-19/prevenção & controle , COVID-19/epidemiologia , COVID-19/psicologia , Estudos Transversais , China/epidemiologia , Masculino , Feminino , Adulto , Inquéritos e Questionários , Pessoa de Meia-Idade , Adulto Jovem , Comportamentos Relacionados com a Saúde , Comportamento do Consumidor/estatística & dados numéricos
2.
Front Psychol ; 14: 1075211, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36968725

RESUMO

Introduction: This study explored the formation mechanism of consumers' self-protective behavior during the COVID-19 pandemic, which is very important for policy settings to regulate consumer behavior. Based on the basic framework of the Protective Action Decision Model (PADM), this study analyzed the formation mechanism of consumers' self-protective willingness from the perspective of risk information, and explained the deviation between consumers' self-protective willingness and behavior from the perspective of protective behavior attributes. Methods: Based on 1,265 consumer survey data during the COVID-19 pandemic, the empirical test was carried out. Results and Discussion: The amount of risk information has a significant positive impact on the consumers' self-protective willingness, where the credibility of risk information plays a positive moderating role between them. Risk perception plays a positive mediating role between the amount of risk information and the consumers' self-protective willingness, and the positive mediating effect of risk perception is negatively moderated by the credibility of risk information. In the protective behavior attributes, hazard-related attributes play a positive moderating role between the consumers' self-protective willingness and behavior, while resource-related attributes play the opposite role. Consumers pay more attention to hazard-related attributes than resource-related attributes, and they are willing to consume more resources to reduce risk.

3.
Environ Sci Pollut Res Int ; 29(56): 84798-84813, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35790627

RESUMO

Biological control (BC) is an important component of green control techniques, and its adoption in the production of fresh produce holds economic and ecological importance as an alternative to chemical pesticides, yet its current adoption rate is not high. To clarify the issue, this study analyzes the factors that influence growers' adoption of BC practices in China's orchard systems. We focus on how marketing outlets and risk attitudes affect farmers' adoption of BC practices. A field survey of 327 pear growers was conducted in three main pear-producing areas of Hebei, Shandong, and Hubei provinces of China between October and December 2020. Results show that farmers' risk aversion has a significant and negative impact on their adoption of BC practices. The market environment is another dramatic factor affecting farmers' adoption. Both green certification and cooperative marketing have a significant role in promoting farmers' adoption of BC practices. Our findings highlight the importance of risk reduction and market environment to BC adoption. Furthermore, it can provide critical information for policymakers in formulating strategies to promote the application and extension of BC practices among farmers in developing countries, such as China.


Assuntos
Fazendeiros , Pyrus , Humanos , Agricultura , China , Marketing
4.
Environ Pollut ; 308: 119663, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35738516

RESUMO

Microplastics could be grazed by marine organisms and possibly transferred to higher trophic levels along the microbial loop. Due to their size and capacity to concentrate heavy metals that trigger joint toxic effects, microplastics (MPs) have already become a severe threat to marine organisms. The detrimental effects of MPs on large marine organisms have been studied, but the combined toxicity of MPs and cadmium (Cd) on protozoan ciliates remains unclear. In the present study, we selected different diameters and concentrations of polystyrene microspheres (PS-MPs) and Cd2+ as model MPs and heavy metals to evaluate their single and combined effects on the periphytic marine ciliate Euplotes vannus in relation to carbon biomass and oxidative stress. The MPs were indeed ingested by Euplotes vannus and significantly reduced the abundance and carbon biomass of ciliate populations. Combined exposure to MPs and Cd2+ not only increased the bioaccumulation of Cd2+ in ciliates but also exacerbated the decrease in ciliate biomass by increasing oxidative stress and membrane damage. In comparison, the effects of nano-sized plastics (0.22 µm) were more harmful than those of micro-sized plastics (1.07 µm, 2.14 µm and 5.00 µm). A smaller size represents a higher potential for penetrating biological members and a stronger adsorption capacity for cadmium. These results provide new insight into the combined toxicity of microplastics and heavy metals on ciliated protozoa and lay a foundation for higher trophic levels and ecosystems.


Assuntos
Euplotes , Metais Pesados , Poluentes Químicos da Água , Organismos Aquáticos , Cádmio/análise , Cádmio/toxicidade , Carbono , Ecossistema , Metais Pesados/toxicidade , Microplásticos , Plásticos/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
5.
Environ Sci Pollut Res Int ; 29(35): 53088-53106, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35279751

RESUMO

China's hog production is facing the dual pressures of the market and environment. A systematic analysis of the ecological efficiency (eco-efficiency) of hog cultivation is of great significance for the development of sustainability and distribution optimization in the industry. This paper investigates the eco-efficiency of hog production and the determinants of eco-efficiency in China using panel data (2004-2018). An optimal super efficiency slacks-based measure (SBM)-Malmquist-Tobit model is adopted for hog production analysis, and the empirical results show a great variation in eco-efficiency across provinces, ranging from 0.557 to 1.19 with a mean value of 0.937 in 2018. The predominant production area of hogs is found being transferred from north to south, with small- and medium-scale predominant production areas shifted from East China to Southwest China, and large-scale predominant production areas shifted from North China to South Central China. Another finding is that eco-efficiency increased by the improvement of technical efficiency. In addition, the Tobit regression results show that rural economic development, the government's investment in environmental control, the market advantage index, and transportation conditions had positive effects on the eco-efficiency; meanwhile, the forbidden policy for livestock cultivation in certain areas, the structure of the hog breeding industry, the density of slaughtered fattened hogs, and the prices of hogs had negative effects on the eco-efficiency.


Assuntos
Desenvolvimento Econômico , Eficiência , Animais , China , Indústrias , Investimentos em Saúde , Suínos
6.
Environ Sci Pollut Res Int ; 29(21): 32171-32179, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35015228

RESUMO

Microalgae have significant amounts of proteins, lipids, carotenoids, vitamins, minerals, and unique pigments. However, with the gradual expansion of microalgae cultivation, hostile biological pollution seriously restricted the large-scale microalgae cultivation and limited the exploitation of its biological resources. Moreover, protozoan poses the greatest threat to microalgae cultivation. Here, the relationship between six marine economic microalgae populations and their ciliate predator Euplotes vannus was examined. And four concentrations were designed for each type of microalgae to carry out the experiment. It was revealed that four species of microalgae inhibit the ciliate population growth at high density. Furthermore, the experiment which was the influence of microalgae at three different growth stages on the growth of the ciliates for these four kinds of high-density inhibitory microalgae was designed. The microalgae inhibitory effects were already exhibited at the end of the exponential growth phase, and it was significantly inhibited during the stationary growth phase. As the microalgae concentration increased, the inhibitory effect became more pronounced. This study provides fundamental data for screening protozoan-inhibiting microalgae and shows potential to be used in algae cultivation.


Assuntos
Cilióforos , Euplotes , Microalgas , Biomassa , Poluição Ambiental , Euplotes/metabolismo
7.
Front Public Health ; 10: 1063384, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36743164

RESUMO

Introduction: The outbreak and spread of the pandemics have been an issue of critical concern globally, posing a significant threat to the health sector globally. This study aimed to examine the basic knowledge and attitudes toward the recommended protective measures at different times, respond to the COVID-19 pandemic, and provide recommendations for developing targeted strategies and measures for preventing and controlling public health emergencies. Methods: The study used self-filled questionnaires to examine the public's knowledge, attitudes, and practices on COVID-19 at two different period, from 20 to 31 March 2020 (the beginning period) and 22-27 April 2022 (the regular epidemic prevention and control period). Descriptive and quantitative analyses were used for statistical analysis. Results and discussion: The survey collected 2375 valid questionnaires. A comparison of the two periods reveals that as the epidemic continued over a long period, the level of knowledge, attitudes toward preventive measures, risk perceptions, and adoption behavior of the respondents at the beginning of the epidemic were significantly higher than during the regular epidemic prevention and control period. With the upsurge in the spread of the epidemic, the public needs a multi-channel, targeted, and all-round guidance and information on prevention and control of the COVID-19, and internalizes knowledge into individual's behavior of actively responding to diseases.When the epidemic lasts for a long time, the relevant agencies should strengthen their monitoring role to promote public compliance with the recommended measures.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Pandemias/prevenção & controle , Inquéritos e Questionários , Conhecimentos, Atitudes e Prática em Saúde
8.
Mar Pollut Bull ; 172: 112868, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34418712

RESUMO

The commercially important marine microalgae Nannochloropsis oceanica is easily ingested by protozoan predators during large-scale cultivation. However, investigations into the effect of microalgae on the growth of protozoa are scant. A feeding experiment was conducted with Euplotes vannus grazing on different concentrations of N. oceanica. The ciliate population was significantly lower in the high concentration of algae than that in the low or medium algal concentration treatments. The density of ciliates cultured in algae filtrate media was significantly lower than that in lysate media and the blank control. Furthermore, the algal cell filtrate was added to three other protozoan populations, and they all gradually lost their ability to move and their body shape changed. This study investigated the interactions between N. oceanica and protozoan predators and provides insight on using microalgal extracellular substances to control biological contamination in the future.


Assuntos
Euplotes , Microalgas , Estramenópilas , Crescimento Demográfico
9.
Foods ; 10(2)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670771

RESUMO

The food safety strategies of companies are a key point in the reduction of food safety risks. In order to encourage the evolution of food safety strategies of companies from food fraud to safety investment, this study builds an evolutionary game model, taking large and small companies as participants, to reveal the dynamic process of spillover effects influencing the choice of food safety strategies of companies. The study shows that (1) the food safety strategies of companies change from safety investment to food fraud, along with the increasing opportunity costs of safety investment. (2) The costs structure of small companies mainly determines whether the industry reaches the equilibrium of safety investment, while the costs structure of large companies mainly determines whether the industry reaches the equilibrium of food fraud. (3) Both competition effects and contagion effects encourage companies to choose safety investment. The more obvious spillover effects of incidents on food safety are, the more likely it is that companies will choose safety investments. (4) Increasing the costs to companies for incidents on food safety and reducing the opportunity cost of safety investment motivates companies to choose safety investment. Consequently, a new orientation of regulations for food safety is formed: the government should allocate different regulatory resources to counteract food fraud behaviors or technologies with a different benefit, should increase the technical costs and costs incurred from committing acts of food fraud, and should expand spillover effects of incidents on food safety.

10.
Sci Total Environ ; 758: 144030, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33340809

RESUMO

Protozoans play an integral role in the microbial loop, an important process of material and energy transfer in marine ecosystems. The number of microplastics in the marine environment has greatly increased, but the potential impacts of small nanoplastics and microplastics on marine organisms remain unclear. Here, we conducted a series of feeding experiments with various concentrations of microplastic beads (ca. 1 µm) to characterize the response of the planktonic ciliated protozoan Strombidium sulcatum to microplastics and a set of additional exposure experiments with four different particle diameters of microplastics to explore whether the feeding response exhibited size selectivity. As the microplastic concentration increased, the number, body size, and biomass of ciliates decreased sharply during the exposure period. Predator biomass in all microplastic treatments was markedly reduced relative to the microplastic-free control. For example, at 72 h of exposure, the biomass in the highest microplastic concentration treatment was observed to decrease by 96.59% relative to the control. There was no obvious difference in the biomass of ciliates exposed to various diameters of microplastics; however, compared with the free bead control, the biomass still significantly decreased. These findings suggest that microplastics in the ocean negatively affect the growth of protozoan microzooplankton that might have accidentally ingested these tiny particles during the feeding process. Generally, this study provides basic and novel data for understanding the effect of microplastics on the microbial loop in marine ecosystems.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Ecossistema , Plásticos , Comportamento Predatório , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
11.
Chemosphere ; 267: 129308, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33352364

RESUMO

Microplastic debris has become a significant global environmental issue. Yet, the effects on ingestion of microplastics by protozoan grazers-an important link in the microbial loop-are scant. Feeding experiments were conducted with the free-living marine ciliate Uronema marinum grazing on cultured bacteria Pseudoaltermonas sp., exposing them to different concentrations or sizes of polystyrene beads for 96 h. The number of beads decreased during exposure experiments. Under the microplastic influence, the ciliate cells were observed to decrease in abundance, body size, and biomass. It was noted that the ciliate biomass in the highest microplastic density treatment was significantly lower than that in the control (98.1% lower) and that microplastics can be ingested by ciliate protozoa which performed an important role in the transportation of energy across the microbial loop. Moreover, carbon biomass of ciliates exposed to microplastics of different particle diameters decreased significantly compared to the control. However, this effect does not seem to vary depending on microplastic sizes. This study is a first step in providing experimental insight into the feeding relationship between microplastics and marine protozoan grazers. Further research based on components of the microbial loop is needed to explore the impacts of microplastics in marine food webs.


Assuntos
Microplásticos , Poluentes Químicos da Água , Biomassa , Ingestão de Alimentos , Monitoramento Ambiental , Plásticos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
12.
Food Secur ; 12(4): 739-747, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32837661

RESUMO

Consumer behavior changes differently in emergencies. Understanding consumer food stockpiling behavior during COVID-19 pandemic can provide critical information for governments and policymakers to adjust inventory and response strategies. This paper analyzed consumer food stockpiling behavior, including the change of food reserve scale and willingness to pay for fresh food reserves in COVID-19. Our paper shows that the scale of food reserve extends from 3.37 to 7.37 days after the outbreak of COVID-19; if available, consumers on average are willing to pay 18.14 yuan (60.47%) premium for fresh products reserves. The result shows that food stockpiling behavior is fueled by a set of multiple motivations and subjective risk perception. Female, high education level and high-income consumers were more likely to reserve larger scale food reserves, but consumers' willingness to pay for fresh food reserves is determined by income. This study was conducted when new infection cases continued to rise in the world. The story of food stockpiling during the COVID-19 pandemic in China is similar with the rest of world. Consumer stockpiling behavior in China can also be expanded to other countries to predict the change of food demand and understand more about consumer preferences in emergencies.

13.
Artigo em Inglês | MEDLINE | ID: mdl-32260264

RESUMO

Information and communication technologies are a ready tool for all strata of society and are indeed redefining the way almost everything is done. Mobile phone technology, in particular, plays a vital role in expediting improvement in the efficiency of the household resource through access to information on various available technologies. Can mobile phones improve the cost efficiency of agricultural production? Comprehension of such effect is critical, especially in the context of the Sustainable Development Goals. We addressed this topic using cross-sectional data from smallholder maize producers in Zambia. The Stochastic Frontier Analysis was applied to estimate cost efficiency. The results indicate that mobile phone use improves the cost efficiency of maize production significantly and as such, adopters have made a rational decision to adopt mobile phone use for information access. Precisely, we found a 10.2% efficiency gap in favor of users. Nevertheless, if non-users were to adopt mobile phones for agricultural information access, maize production per hectare would increase by 21.38%. Eventually, food production would be increased in an environmentally friendly manner and the price of maize would be set at a competitive price within the region because agricultural inputs would be allocated cost efficiently. Therefore, in an attempt to minimize production cost in food production, this study strongly endorses the use of mobile phones for agricultural information access.


Assuntos
Agricultura , Uso do Telefone Celular , Telefone Celular , Envio de Mensagens de Texto , Agricultura/economia , Estudos Transversais , Tomada de Decisões , Zâmbia
14.
Pak J Med Sci ; 32(5): 1164-1168, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27882014

RESUMO

OBJECTIVE: To investigate the expressions of peripheral regulatory T cells (Treg) and T helper cells (Th17) as well as related cytokines in peripheral blood of patients with inflammatory bowel disease (IBD). METHODS: One hundred four cases of IBD patients admitted in our hospital were selected for this study. One hundred cases of people receiving healthy physical examination were included in the control group in the corresponding period. The levels of CD4+CD25+Treg and Th17 subsets were analyzed in peripheral blood of two groups using flow cytometry. The expressions of IL-10, TGF-ß1, IL-17 and IL-23 mRNA and protein were detected using real-time fluorescence quantitative PCR and ELISA. RESULTS: Compared with the control group, the proportion of Treg in peripheral blood was decreased significantly in observation group (P<0.05), the proportion of Th17 cells was increased significantly (P<0.05), and Treg/Th17 was decreased significantly (P<0.05). Compared with the control group, the expressions of IL-10 and TGF-ß1 mRNA and protein in peripheral blood of patients were significantly down-regulated in observation group, while the expressions of Th17 cytokines IL-17 and IL-23 mRNA and protein were significantly increased (P<0.05). CONCLUSION: The proportion of Th17 and increased cytokine level suggested the inflammatory level was higher in IBD patients. The down regulations of Treg and cytokine suggested that the immunosuppression function was down-regulated in IBD patients, and the disproportionality might be one of the mechanisms of IBD.

15.
Pak J Pharm Sci ; 28(2 Suppl): 697-700, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25796160

RESUMO

This research aims to analyze the curative effect and security of lauromacrogol injection and absolute ethyl alcohol treating simplex hepatic cyst respectively. The simplex hepatic cyst patients were divided into lauromacrogol group (86 cases, research group) and absolute ethyl alcohol group (80 cases, control group). Both two groups received sclerotherapy of thoracic drainage under ultrasonic guidance and the curative effect and untoward effect were observed. The result showed there was no hemorrhage or infection within two groups. During the therapeutic process, 45 patients (56.3%) suffered from pain at different degrees and 23 cases were found with symptom of drunkenness in control group, while the patients in the research group were found with no obvious discomfort. A week after treatment, 23 patients (25.0%) in control group still remained to have swelling pain at upper right stomach, while there were only 9 in treatment group (10.5%), and the difference was of statistical significance (X(2)=6.037, P<0.05). through 6 months of follow-up visit after the operation, we found the cure rate of lauromacrogol group was 94.6% and absolute ethyl alcohol was 92.6%, and the difference between these two groups was of no statistical significance (P>0.05). The results showed that, in the treatment of cystosclerosis with absolute ethyl alcohol injection under ultrasonic guidance, some patients suffered pain and the symptom of drunkenness at different degrees, whereas, lauromacrogol was effective with no untoward effects, therefore it is worthy of clinical popularization and application.


Assuntos
Cistos/terapia , Etanol/administração & dosagem , Hepatopatias/terapia , Polietilenoglicóis/administração & dosagem , Soluções Esclerosantes/administração & dosagem , Escleroterapia/métodos , Adulto , Idoso , Cistos/diagnóstico , Etanol/efeitos adversos , Feminino , Humanos , Injeções , Hepatopatias/diagnóstico , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/efeitos adversos , Soluções Esclerosantes/efeitos adversos , Escleroterapia/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia de Intervenção
16.
Artif Organs ; 32(12): 925-31, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19133020

RESUMO

There is increasing evidence showing that adult stem cells are useful for tissue regeneration. Bone marrow mesenchymal stem cells (MSCs) are self-renewing and are potent in differentiating into multiple cells and tissues. To investigate the practicability of repairing burn wounds with tissue-engineered (TE) skin combined with bone MSCs, we established a burn wound model in the porcine skin. With a controlling temperature and time of the burning device to obtain different degrees of burn wounds, a deep dermal partial thickness burn was introduced to the porcine skin using a heated-brass contact injury at 100 degrees C for 20 s. Collagen-GAG scaffolds were utilized as the matrix; MSCs separated from pigs were seeded on them to form the skin equivalent. When grafted to the burn wounds, the TE skin containing MSCs showed better healing and keratinization, less wound contraction, and more vascularization. Grafts proliferated well and contributed to the neo-tissues. These data suggest that TE skin containing MSCs in a burn defect can accelerate wound healing and receive satisfactory effects.


Assuntos
Queimaduras/cirurgia , Transplante de Células-Tronco Mesenquimais/métodos , Modelos Animais , Pele Artificial , Engenharia Tecidual/métodos , Cicatrização , Animais , Células da Medula Óssea/citologia , Células Cultivadas , Colágeno/química , Células-Tronco Mesenquimais/citologia , Pele/patologia , Pele/ultraestrutura , Suínos
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