Malaria is still a major public health concern in Cameroon as more than 20 million people are at risk of the disease. Despite the government’s effort to scale up the distribution of long lasting insecticide-treated b...Malaria is still a major public health concern in Cameroon as more than 20 million people are at risk of the disease. Despite the government’s effort to scale up the distribution of long lasting insecticide-treated bed nets (LLINs), full ownership and optimal use is still limited. In 2021, over a million LLINs were made available for distribution in the South West Region. However, the current situation of malaria has not yet been ascertained following the 2021 mass distribution campaign (MDC). Therefore, the aim of this study was to determine LLIN ownership, coverage, usage and the prevalence of malaria following the 2021 MDC in the Tiko Health District (THD), South West Region of Cameroon. A cross-sectional study was carried from May 1 to 27, 2022 in which a multi-stage sampling technique was used to enroll eligible participants. Data were collected from household heads using questionnaires and capillary blood samples collected from consented household members were used to test for malaria. Data were analyzed using SPSS version 25 at 0.05 significance level. From the 150 households surveyed, 96 (64.0%) owned a mosquito net before the recent MDC. There was an overall significant increase (p p = 0.644) in LLINs ownership between areas where door-to-door (79.5%) and fixed “Hit and Run” (75.8%) strategies were used in the distribution of LLINs in THD. The prevalence of malaria was 10.2%. The regular use of LLINs was significantly associated (p = 0.007) with low malaria prevalence. The 2021 MDC had an impact on malaria prevalence in those who properly used them.展开更多
Background: In lacustrine communities, whether in Benin or elsewhere, populations use impregnated mosquito nets (IMNs) as fishing nets. This depletes the lake of its fishery resources, which in turn are contaminated b...Background: In lacustrine communities, whether in Benin or elsewhere, populations use impregnated mosquito nets (IMNs) as fishing nets. This depletes the lake of its fishery resources, which in turn are contaminated by the pyrethroids impregnated in the nets. This study aims to determine the scale and factors associated with the use of pyrethroid-impregnated mosquito nets as fishing tools in the municipality of Sô-Ava in Benin. Methods: This is a cross-sectional and analytical study with two components. First, a quantitative component was made up of 280 volunteers who were interviewed in the seven districts of the city. Data collection was done in two phases: the first from September to October 2020, and the second in August 2022. Data were analyzed with Stata and logistic regression was used. Another qualitative component was made up of forty participants chosen by reasoned choice, of which 32 were split into four focus groups of eight members each, and the rest participated in semi-structured interviews. Triangulation of the different sources was used to analyze the data. Results: Around 67% of the population reported using impregnated mosquito nets as fishing tools and 33% exclusively for malaria. Seasonal fishermen (ORa = 2.03, CI = 1.35 - 4.97, P = 0.004) and years of professional experience (ORa = 1.53, CI = 1.00 - 2.05, P = 0.021) increase the risk of using these nets as fishing tools. The use of insecticide-treated mosquito nets against mosquitoes causes skin scratching and impairs breathing because of the impregnation products, as reported by respondents. Conclusion: A high prevalence of inappropriate use of impregnated mosquito nets in fishing practices is highlighted in this study. Interviews in the field revealed that nets are diverted for fishing purposes to increase the volume of catches. Consequently, it will be appropriate to assess the pyrethroid content in water and fishery products.展开更多
This paper deals with the supervisory control problem of discrete event systems modeled by labeled Petri nets. The system is originally unbounded. First, the solvability of the problem is confirmed. A necessary condit...This paper deals with the supervisory control problem of discrete event systems modeled by labeled Petri nets. The system is originally unbounded. First, the solvability of the problem is confirmed. A necessary condition is given and proven for the existence of a feasible priority-based controller based on the notions of liveness and transition invariants. Next, a cyclic behavior graph is constructed, which shows the reachable markings that guarantee the maximum liveness of the system within a given bound vector. Finally, an on-line control strategy is proposed to enforce boundedness and liveness to the given system by appending priority relations to transitions. The dynamic priority relation changes flexibly according to the current state of the system and enforces the system evolving in a bounded and live manner. In addition, numerical examples are studied to verify the validity of the proposed approach that remains the structure of the plant net and is efficient for on-line control.展开更多
文摘Malaria is still a major public health concern in Cameroon as more than 20 million people are at risk of the disease. Despite the government’s effort to scale up the distribution of long lasting insecticide-treated bed nets (LLINs), full ownership and optimal use is still limited. In 2021, over a million LLINs were made available for distribution in the South West Region. However, the current situation of malaria has not yet been ascertained following the 2021 mass distribution campaign (MDC). Therefore, the aim of this study was to determine LLIN ownership, coverage, usage and the prevalence of malaria following the 2021 MDC in the Tiko Health District (THD), South West Region of Cameroon. A cross-sectional study was carried from May 1 to 27, 2022 in which a multi-stage sampling technique was used to enroll eligible participants. Data were collected from household heads using questionnaires and capillary blood samples collected from consented household members were used to test for malaria. Data were analyzed using SPSS version 25 at 0.05 significance level. From the 150 households surveyed, 96 (64.0%) owned a mosquito net before the recent MDC. There was an overall significant increase (p p = 0.644) in LLINs ownership between areas where door-to-door (79.5%) and fixed “Hit and Run” (75.8%) strategies were used in the distribution of LLINs in THD. The prevalence of malaria was 10.2%. The regular use of LLINs was significantly associated (p = 0.007) with low malaria prevalence. The 2021 MDC had an impact on malaria prevalence in those who properly used them.
文摘Background: In lacustrine communities, whether in Benin or elsewhere, populations use impregnated mosquito nets (IMNs) as fishing nets. This depletes the lake of its fishery resources, which in turn are contaminated by the pyrethroids impregnated in the nets. This study aims to determine the scale and factors associated with the use of pyrethroid-impregnated mosquito nets as fishing tools in the municipality of Sô-Ava in Benin. Methods: This is a cross-sectional and analytical study with two components. First, a quantitative component was made up of 280 volunteers who were interviewed in the seven districts of the city. Data collection was done in two phases: the first from September to October 2020, and the second in August 2022. Data were analyzed with Stata and logistic regression was used. Another qualitative component was made up of forty participants chosen by reasoned choice, of which 32 were split into four focus groups of eight members each, and the rest participated in semi-structured interviews. Triangulation of the different sources was used to analyze the data. Results: Around 67% of the population reported using impregnated mosquito nets as fishing tools and 33% exclusively for malaria. Seasonal fishermen (ORa = 2.03, CI = 1.35 - 4.97, P = 0.004) and years of professional experience (ORa = 1.53, CI = 1.00 - 2.05, P = 0.021) increase the risk of using these nets as fishing tools. The use of insecticide-treated mosquito nets against mosquitoes causes skin scratching and impairs breathing because of the impregnation products, as reported by respondents. Conclusion: A high prevalence of inappropriate use of impregnated mosquito nets in fishing practices is highlighted in this study. Interviews in the field revealed that nets are diverted for fishing purposes to increase the volume of catches. Consequently, it will be appropriate to assess the pyrethroid content in water and fishery products.
基金the Project of Industrial Internet and Integration of Industrialization and Industrialization of Guangxi,China under Grant No.Guigong2021-37.
文摘This paper deals with the supervisory control problem of discrete event systems modeled by labeled Petri nets. The system is originally unbounded. First, the solvability of the problem is confirmed. A necessary condition is given and proven for the existence of a feasible priority-based controller based on the notions of liveness and transition invariants. Next, a cyclic behavior graph is constructed, which shows the reachable markings that guarantee the maximum liveness of the system within a given bound vector. Finally, an on-line control strategy is proposed to enforce boundedness and liveness to the given system by appending priority relations to transitions. The dynamic priority relation changes flexibly according to the current state of the system and enforces the system evolving in a bounded and live manner. In addition, numerical examples are studied to verify the validity of the proposed approach that remains the structure of the plant net and is efficient for on-line control.
