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Analysis of environmental samples obtained from the Live Poultry Markets (LPMs) of Dhaka City, Bangladesh, has revealed that the highest degree of prevalence of highly pathogenic avian influenza A (HPAI, H5N1), besides other subtypes of the LPAI virus, poses the plausible risk of transmission of these viruses between human and poultry species. The present study was conducted using the OIE risk analysis framework to assess the risk level of each pathway successively. The estimated risk parameters were integrated towards to obtain the overall risk level for each specific HPAI transmission pathway using the matrix adapted by Cristobel Zepeda accompanying other expert consultations. The relevant data obtained from published and unpublished sources, together with survey data of field observations, were used to formulate and confirm the risk pathways and their associated risks. The results revealed that the risk of the release of the HPAI virus was medium when exposure was high. Additionally, the consequence would be considered very high with a medium degree of uncertainty for all parameters. Ultimately, the overall risk for transmission was estimated as medium with a medium degree of uncertainty. The findings of this study reveal that there is a significant threat that HPAI virus transmission could occur among poultry and humans and effectively sustain within the environment of the LPMs. Our findings are primarily focused on public health considerations, the hygienic slaughter of poultry and the relevant cleaning and sanitation practices conducted in the LPMs to support evidence‐based decision‐making processes. The findings of the study have the potential to be used to formulate effective risk reduction measures and can be further adapted in low‐resource settings without major infrastructural changes required of the LPMs. All of which would reduce the risk of HPAI virus release and further lessen the degree of exposure and transmission in established LPMs.  相似文献   
2.
Chakma J  Sammut SM 《Science (New York, N.Y.)》2011,331(6017):532-3; author reply 533-4
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3.
The entomopathogenic nematode, Steinernema carpocapsae, was evaluated for control of the potato tuber moth, Phthorimaea operculella, under laboratory conditions. We evaluated different concentrations of S. carpocapsae for control of 2 nd, 3 rd, and 4 th instar P. operculella. The median lethal concentration(LC50) of S. carpocapsae infective juveniles(IJs) to 2 nd, 3 rd and 4 th instar larvae of P. operculella was 200, 363, 181 IJs mL–1, respectively. With the extension of treatment time, the cumulative mortality increased for 2 nd, 3 rd, and 4 th instar larvae and pupae of P. operculella. Fourth instars were the most susceptible for all observation periods. Therefore, our results suggest that S. carpocapsae could be an effective biological control agent for P. operculella.  相似文献   
4.
Natural forests offer numerous benefits to indigenous communities and society at large. Incomes from forest sources play an important role in rural households. In addition to this, environmental sources in the forests contribute significantly to rural households’ livelihoods and economic well-being. This paper examines the contributions of forests to the livelihoods of the Chakma tribe in Bangladesh. Using the data from 60 randomly sampled households from three villages, it measured forest-resource use with a monetary yardstick. As revealed through analyses, natural forest-sourced income occupies the second-largest share in total average household income next to shifting cultivation income in the study area. Forest products represent an important component in the local livelihoods, with a direct forest income of 11,256?tk?year?1?household?1 (tk = taka, the national currency of Bangladesh; US$1?=?tk70), or 11% of the total income, in addition to the households receiving monetary benefits of 18,951?tk?year?1?household?1, or 21% of the total income, through the consumption of forest products. The remaining income came from shifting cultivation practice. It was also observed that larger families with more people gathering forest products realized more forest income. This study will be relevant to forest and environmental policy-makers as well as indigenous community development practitioners.  相似文献   
5.
Homestead forests contribute substantially to the rural economy of Bangladesh. Rural people depend on trees and plants for their energy usage, housing, food and other forms of subsistence livelihood. In order to identify the potential role of forests on homestead dwellers, an empirical field investigation was conducted in the four Upazilas of Mymensingh district of Bangladesh. It was found that land holdings of the respondents within the four sites are the highest in Mymensingh. The study made an important observation that among all homestead vegetation between 5–6 years old, tree species are generally preferred over plants. This is perhaps due to the efforts of the social forestry extension service to demonstrate that planting trees is an important long-term investment. In all four Upazilas, there was a significant correlation between household annual income and homestead forestry, agriculture and fisheries practice, suggesting that higher income families tend to have larger holdings of homesteads, farms and pond areas. Three Upazilas displayed a strong positive relationship (nearly 45%) between homestead forest areas and annual family income; however, the Fulbaria Upazila showed a very poor relationship (0.2%) in this regard. The results of this study suggest that homestead forests play a positive role in the rural economy, in addition to helping mitigate the increasing problem of deforestation in Bangladesh.  相似文献   
6.

BACKGROUND

The tomato potato psyllid, Bactericera cockerelli (Šulc) is a new invasive pest in Western Australia, which may disperse across the whole of Australia within a few years and cause significant economic losses. Chemical control is the most widely used approach to manage B. cockerelli, but insect resistance, chemical residue and effects on non-target species have become an increasing concerned. Therefore, in this study, the biocontrol potential of variegated lady beetle, Hippodamia variegata (Goeze) was investigated. The impact of utilizing B. cockerelli as a food source on the predator's development and reproduction was assessed by formulating age-stage, two sex life tables. The predatory potential of H. variegata on B. cockerelli nymphs was assessed in a closed arena and the effects of releasing H. variegata for the control of B. cockerelli were then evaluated.

RESULTS

H. variegata could successfully develop and oviposit when feeding on B. cockerelli. However, both survival and the rate of development were higher for H. variegata feeding on Myzus persicae (Sulzer) than B. cockerelli or a mixed population of B. cockerelli and M. persicae. A type II functional response was observed for H. variegata. In the greenhouse, the releases of H. variegata larvae reduced the number of B. cockerelli nymphs by up to 66% and adults by up to 59%, which positively influenced the plant chlorophyll content and biomass.

CONCLUSIONS

This study demonstrated the potential of the resident generalist predator, H. variegata as a biocontrol agent for the invasive pest, B. cockerelli, which may help improving current management strategies. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
7.
Groundwater contamination by leakage and spill of petroleum hydrocarbons from underground storage tanks has been a major environmental concern. Among various remediation alternatives, the vacuum-enhanced free product recovery (VFPR) is an important technology to extract light nonaqueous-phase liquids (LNAPLs) from subsurface. However, efficient design of a VFPR system was challenging to practitioners, since the process of hydrocarbon removal is costly and time consuming. To address such a problem, an integrated study system for optimizing the VFPR process was developed through coupling a numerical modeling system, a multivariate regression technique and nonlinear optimization model into a general framework. A two-dimensional multiphase flow simulation system was provided for modeling VFPR processes. An iterative stepwise-inference regression (ISIR) method was advanced for establishing a linkage between remediation actions and system responses. A nonlinear optimization model embedded with ISIR was then established for generating desired operating conditions. The results from a case study demonstrated that the established optimization model could effectively analyze tradeoffs between various environmental and economical considerations, and provide effective decision supports for site remediation practices. Compared with the conventional stepwise-cluster analysis method, the proposed ISIR method was more efficient and reliable in approximating relationships between remediation actions and system responses, and could significantly enhance the robustness of optimization solutions.  相似文献   
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