Food safety and hygiene practices require a multisectoral approach including food, water, sanitation, waste management, transport, education, trade, policies and programs that enable safe food preparation, storage and...Food safety and hygiene practices require a multisectoral approach including food, water, sanitation, waste management, transport, education, trade, policies and programs that enable safe food preparation, storage and service. Unsafe food can cause illness keeping people from achieving their full potential and death. This was a descriptive study that uses a mixed method approach to derive insights into the characteristics of food vendors related to demography, knowledge, practices, infrastructure, compliance and recommendation for a policymaking framework. Using the Lemeshows’ sample size formula, 473 vendors from formal (restaurants) and informal (cookri-baffa/table top) sites were interviewed and observed. We found from discussions that respondents had a good understanding on how to keep food safe. However, observed practices were poor 93% handled food with their bare hands, 83% did not cover their hair, and 76% did not wear an apron whilst handling, preparing or serving food, 61% did not keep their finger nails clean or short and 57% did not wash their hand before preparing or serving food. Over half (51%) had access to a toilet but 32% reported their use required payment and emphasized their poor condition/inadequate management. Nearly half (47%) of the vending sites did not have a handwashing facility, with soap and water available. Only 7% reported having any authority oversight of food safety. Food safety and hygiene practices in most cookri shops and restaurants was ‘poor’ with very limited surveillance system in place by competent authorities for compliance of food operators. Hand washing, clean surroundings, and covered food were the most common and emphasized practices to mitigate the risks associated with unsafe food.展开更多
Investigations into the Andean orocline revealed a counterclockwise rotation of about 37° in the north and a clockwise rotation of about 29° in the south. This rotation would have started in the Eocene becau...Investigations into the Andean orocline revealed a counterclockwise rotation of about 37° in the north and a clockwise rotation of about 29° in the south. This rotation would have started in the Eocene because the Nazca and South American plates converged. The transition zone between the Puna and the Sierras Pampeanas has a clockwise rotation pattern. Our new data show that the NE convergence of the Nazca and South American plates caused the counterclockwise rotation around the NW end of the Sierras Pampeanas. The temperature rise during a magmatic activity at 13 Ma would have favored a counterclockwise rotation of the mountain blocks of about 20° on a detachment zone within 10 to 15 km of depth. These range rotations generated local stress tensors trending NE and NW, facilitating the development of valleys, basins, mineralized dikes, mineral deposits, and alluvial fans separated from their origin. The Atajo fault shows both ductile and brittle characteristics. A mylonitic belt from the Sierra de Aconquija was juxtaposed on the rocks of the Ovejería Block and the Farallón Negro Volcanic Complex by reverse vertical displacement, and a dextral horizontal component of displacement resulted in curvatures that gave rise to pull-apart basins and step over features. The Santa Maria Valley, Campo del Arenal, Hualfín Valley, and Pipanaco salt flat most likely constituted a vast early Miocene basin rarely interrupted by low feature relief.展开更多
Food safety, nutrition, health and wellbeing are inextricably linked. This study investigated the environmental, awareness and practices amongst both food vendors and consumers in and around Freetown the capital of Si...Food safety, nutrition, health and wellbeing are inextricably linked. This study investigated the environmental, awareness and practices amongst both food vendors and consumers in and around Freetown the capital of Sierra Leone. The population of the area has vastly out-grown the infrastructure laid down before and since independence. De-centralization of authority to local councils as recommended post-war has only been partial. The role of local versus central government in the planning and maintenance of water, sanitation and market-infrastructure and related policies was explored. This is a qualitative study that used semi-structured interviews with vendors, consumers and 29 key informants. Amongst an estimated population of 5386 actors in food services a sample size of 309 vendors, consumers in and around the 12 busiest market hubs in Western Area Urban and Rural Districts were sampled. Most of the respondents described “food safety” as “good-to-eat, well taken care-off, and free from germs”. The respondents cited that main causes to unsafe food are poor hygienic practices: 38%, contamination by flies: 28%, uncovered food/ improper handling/poor personal hygiene: 21%, and environmental factors, such as improper refuse disposal: 11%. Respondents expressed that consuming unsafe foods can lead to diarrhoea: 34%, food poisoning: 24%, vomiting: 17%, stomach ache/pain: 16%, or typhoid: 9%. Various measures to improve food safety were cited as hand washing: 60%, cleaning surroundings: 57%, covering food: 56%, washing utensils: 52%, covering hair: 42% and using a face mask: 32%. However almost 76% of food vendors interviewed were trading near gutters, where muddy/dirty water settled, with slippery floors, discarded plastic waste, flies and inadequate water, sanitation, and/or storage facilities. None of the food vendors had had any formal training on food safety. Despite progress recently made in solid and liquid waste management during the “Transform Freetown” agenda much more improvement in infrastructure and behaviour change is required. Similarly, despite improvements in formal market facilities the pattern of informal street trading remains the most prevalent especially for the poor. The link between “safe food” and good health was only partially understood, whilst the widespread application of recommended practices to reduce risks was lacking due in part to inadequate infrastructure. As the importance of food safety becomes better understood by administrators and the public the investments required in infrastructure and social and behavioural change will contribute towards a healthier environment and outcomes.展开更多
Rainfall and temperature are the important variables that are often used to trace climate variability and change. A Perception study and analysis of climatic data were conducted to assess the changes in rainfall and t...Rainfall and temperature are the important variables that are often used to trace climate variability and change. A Perception study and analysis of climatic data were conducted to assess the changes in rainfall and temperature and their impact on crop production in Moyamba district, Sierra Leone. For the perception study, 400 farmers were randomly selected from Farmer-Based Organizations (FBOs) in 4 chiefdoms and 30 Agricultural Extension Workers (AWEs) in the Moyamba district were purposely selected as respondents. Descriptive statistics and Kendall’s test of concordance was used to analyze the data collected from the farmers and AEWs. Data for the analysis of variability and trends of rainfall and temperature from 1991 to 2020 were obtained from the Sierra Leone Meteorological Agency and Njala University and grouped into monthly, seasonal and annual time series. Regression analyses were used to determine the statistical values and trend lines for the seasonal and annual time series data. The Mann-Kendall test and Sen’s Slope Estimator were used to analyze the significance and magnitude of the trends respectively. The results of both studies show evidence of climate change in the Moyamba district. A substantial number of farmers and AEWs perceived a decrease in the annual rainfall amount, length of the rainy season, a late start and end of the rainy season, an increase in the temperature during the day and night, and a shortened harmattan period over the last 30 years. Analysis of the meteorological data shows evidence of variability in the seasonal and annual distribution of rainfall and temperature, a decreasing and non-significant trend in the rainy season and annual rainfall and an increasing and significant trend in seasonal and annual temperature from 1991 to 2020. However, the observed changes in rainfall and temperature by the farmers and AEWs partially agree with the results of the analyzed meteorological data. The majority of the farmers perceived that;adverse weather conditions have negatively affected crop production in the district. Droughts, high temperatures, and irregular rainfall are the three major adverse weather events that farmers perceived to have contributed to a substantial loss in the yields of the major crops cultivated in the district. In response to the negative effects of adverse weather events, a substantial number of farmers take no action due to their lack of knowledge, technical or financial capacity to implement climate-sensitive agricultural (CSA) practices. Even though few farmers are practicing some CSA practices on their farms, there is an urgent need to build the capacity of farmers and AEWs to adapt to and mitigate the negative impacts of climate change. The most priority support needed by farmers is the provision of climate-resilient crop varieties whilst the AEWs need training on CSA practices.展开更多
In this study,the Radio Direction Finding method is proposed for the detection of electromagnetic signals,in the VLF band,to try to anticipate the occurrence of potentially destructive geophysical events.The experimen...In this study,the Radio Direction Finding method is proposed for the detection of electromagnetic signals,in the VLF band,to try to anticipate the occurrence of potentially destructive geophysical events.The experimentation concerns the interception of electromagnetic anomalies in Sierra Leone,in the five-day time window,associated with seismic events that could potentially generate tsunamis.The area of investigation is Sierra Leone,whose coastline is subjected to tidal wave hazards triggered by earthquakes generated in the Mid-Atlantic Ridge.Although Sierra Leone is not affected by recurrent earthquakes,there is nevertheless a low probability,estimated at 2 percent,of the occurrence of destructive earthquakes in the next 50 years.Also in estimates,the risk of rogue and potentially damaging waves is estimated to strike the Sierra Leone coast at least once in the next 10 years.The Radio Direction Finding experiment carried out continuously 24/7,has shown a close relationship between increased radio-anomalies,in the frequencies of 6,000 Hz,a time window between electromagnetic anomaly detection and the imminence of an earthquake,and higher frequency times for the risk of earthquake occurrence in the Mid-Atlantic Ridge.展开更多
Objective People in Western Africa suffer greatly from febrile jaundice, which is caused by a variety of pathogens. However, yellow fever virus(YFV) is the only pathogen under surveillance in Sierra Leone owing to the...Objective People in Western Africa suffer greatly from febrile jaundice, which is caused by a variety of pathogens. However, yellow fever virus(YFV) is the only pathogen under surveillance in Sierra Leone owing to the undeveloped medical and public health system there. Most of the results of YFV identification are negative. Elucidation of the pathogen spectrum is required to reduce the prevalence of febrile jaundice. Methods In the present study, we used Ion Torrent semiconductor sequencing to profile the pathogen spectrum in archived YFV‐negative sera from 96 patients in Sierra Leone who presented with unexplained febrile jaundice. Results The most frequently identified sequencing reads belonged to the following pathogens: cytomegalovirus(89.58%), Epstein‐Barr virus(55.21%), hepatitis C virus(34.38%), rhinovirus(28.13%), hepatitis A virus(20.83%), coxsackievirus(10.42%), Ebola virus(8.33%), hepatitis E virus(8.33%), lyssavirus(4.17%), leptospirosis(4.17%), chikungunya virus(2.08%), Crimean‐Congo hemorrhagic fever virus(1.04%), and hepatitis B virus(1.04%). Conclusion The distribution of sequencing reads suggests a broader spectrum of pathogens for consideration in clinical diagnostics and epidemiological surveillance in Sierra Leone.展开更多
The Sierra Norte de Puebla, Mexico, has a record of hundreds of mass removal processes triggered by rainfall, where the intensity and duration of the rain are the main mechanisms. In order to determine threshold value...The Sierra Norte de Puebla, Mexico, has a record of hundreds of mass removal processes triggered by rainfall, where the intensity and duration of the rain are the main mechanisms. In order to determine threshold values for precipitation as a cause of a landslide, the prior, marginal and conditional probabilities were calculated. A Bayesian method was used for one-dimensional (precipitation intensity) and two-dimensional (precipitation intensity and duration) analysis. This suggested a high probability of mass movement when the precipitation exceeds 60 mm within ten days. A proposed warning system is based on classes in which the threshold is exceeded.展开更多
Ebola virus disease reemerged in Western Africa in 2014.Chinese Center for Disease Control and Prevention dispatched the first Ebola virus(EBOV)detection team to run newly established Sierra Leone-China Friendship B...Ebola virus disease reemerged in Western Africa in 2014.Chinese Center for Disease Control and Prevention dispatched the first Ebola virus(EBOV)detection team to run newly established Sierra Leone-China Friendship Biological Safety Laboratory.The aims of study were to understand epidemiology,clinical manifestations and survival time of EBOV in patient's blood.A total of 913specimens were tested between March 11 and April20, 2015. EBOV positivity occurred in 7.37% of the blood and 0.53% in throat swabs.展开更多
The impact of summer cattle grazing on water quality during three very different climatic years in the Sierra Nevada was investigated. Water year 2009 had near normal precipitation;2010 had late precipitation and snow...The impact of summer cattle grazing on water quality during three very different climatic years in the Sierra Nevada was investigated. Water year 2009 had near normal precipitation;2010 had late precipitation and snowmelt;and 2011 had 150% above normal precipitation. Surface waters were tested for pathogenic bacteria indicators fecal coliform, E. coli, and total coliform before and after cattle were released onto summer grazing allotments. Water samples were collected from meadow stream sites up to 6 weeks before and up to 6 weeks after cattle grazing began. Streams passing through ungrazed meadow served as controls. Eight sample sites were between 1694 m and 2273 m in elevation;one site was lower at 1145 m in elevation. Samples were transported within 6 hours to a water analysis laboratory, where samples were analyzed following standardized laboratory methods. Results showed that individual site and total mean concentrations of E. coli in surface waters were within regulatory standards before cattle arrived during each of the 3 study years. After the beginning of grazing, mean E. coli counts increased as follows: 2009 from 8 to 240 CFU/100mL, 2010 from 7 to 561 CFU/10mL;2011 from 7 to 657 CFU/100mL (p < 0.05 all years). Total coliform bacteria and fecal coliform concentrations showed the same pattern. This study shows that cattle grazing in the high elevation Sierra Nevada results in a significant increase in indicator bacteria. This impact on the watersheds occurs despite widely variable annual climatic conditions.展开更多
Ensuring availability and sustainable management of water and sanitation for all by 2030 is Goal 6 of the Sustainable Development Goals (SDGs). Since developing countries especially in Africa would struggle to meet th...Ensuring availability and sustainable management of water and sanitation for all by 2030 is Goal 6 of the Sustainable Development Goals (SDGs). Since developing countries especially in Africa would struggle to meet this target, this study was conceived. Hence, the study was designed to assess the water quality for physiochemical parameters around a mined out site in southern Sierra Leone with the view to determine their levels, determine related associations among indicators and explore environmental forensic options. A finite population correction factor was used to identify fifty (50) groundwater sources from one hundred and fifty two (152) in nine (9) sections of Moriba Town, in Moyamba District, Sierra Leone which constitute the sample size. The study assessed sixteen (16) physical and chemical indicators across the defined boundary of the sample size. Results indicated that almost 80% of all the indicators were in good agreement with water quality standards with the exception of three. Turbidity correlated strongly with , Al and ?and almost all other indicators did not show meaningful association. High values with significant variance of water quality indicators of physical to chemical ratio were observed for pH, temperature, electrical conductivity (EC) and total dissolved solids (TDS) but no such observation was noted for turbidity. On the whole, the water quality was judged to be good, although more pro active actions were encouraged by the local people and the mining company so as to reduce contamination in some areas.展开更多
Rice is the main food of Sierra Leoneans and an important source of employment and income for rural communities. According to the West African Rice Development Association report, annual consumption of rice is amongst...Rice is the main food of Sierra Leoneans and an important source of employment and income for rural communities. According to the West African Rice Development Association report, annual consumption of rice is amongst the highest in SubSaharan Africa(SSA), 104 kg. Mainly, small scale farmers who are resource poor on both the upland and various lowlands grow rice. Sierra Leone has not been able to produce enough rice to meet its local consumption demand for a very long time now. 530 000 MT of milled rice is the required consumption need of the Sierra Leonean population per annum. In 2007, national paddy rice production was projected at 638 000 MT. The level of rice self-sufficiency rose from 50.57% in 2002 to 62.15% in 2006 and then to 63.49% in 2007. The remainder must be imported at increasingly expensive prices in the current situation of high food prices, which includes rice. The price of rice has seen a steady increase in the entire country. What most affected by this, is the low-income urban and peri-urban households. The promotion of domestic rice production is therefore a key element in the strategies for improving rice self-sufficiency, stimulating economic growth and increasing rural income. Therefore, supporting rice production programme is the only solution to pull the country out of the worsening rice situation and maintain the present trend in rice self-sufficiency. Therefore, having an understanding of the strategic interventions in rice production in Sierra Leone is an important ingredient in the promotion and attainment of rice self-sufficiency.展开更多
In a bid to enhance the integrity and health of selected network of ecosystems and effectively manage them in Sierra Leone, a baseline assessment of butterfly diversity of two wetland ecosystems Mamunta Mayosso Wildli...In a bid to enhance the integrity and health of selected network of ecosystems and effectively manage them in Sierra Leone, a baseline assessment of butterfly diversity of two wetland ecosystems Mamunta Mayosso Wildlife Santuary (MMWS) and Sierra Leone River Estuary (SLRE) affected by different environmental stressors was undertaken as part of the Sierra Leone Wetland Conservation Project (SLWCP). We hypothesised that different environmental stressors affect butterfly communities in wetlands in Sierra Leone and the higher the stress the lower the butterfly diversity in an area. Sampling was conducted via field identification by wing patterns, flight mode, direct counts along transects and charaxes trapping. A total of 2300 individuals representing 95 species of butterflies were recorded. Though butterflies were evenly distributed at both sites, MMWS recorded the highest richness and abundance of butterflies during both seasons. This observation is reported to be because of high environmental stressors such as mining, agriculture and pollution from factories in the SLRE. The results further show that MMWS is made up of a mosaic of different vegetation patches that support higher diversity of butterfly species. This study also reveals that anthropogenic activities have a negative impact on butterfly diversity.展开更多
The glacial morphology of southern South American presents invaluable evidence to reconstruct former glacier behaviour and its relation to climate and environmental changes. However, there are still spatial and tempor...The glacial morphology of southern South American presents invaluable evidence to reconstruct former glacier behaviour and its relation to climate and environmental changes. However, there are still spatial and temporal gaps in the reconstruction of the Holocene Patagonian glacial landscape. Here we present the first geomorphological record for the Sierra Baguales Mountain Range(SBMR), forming the eastern foothills of the Southern Patagonian Andes 200 km from the Pacific coast. This area is topographically isolated from the Southern Patagonian Ice Field(SPIF), and is affected by the Westerly Winds. The study area shows evidence of ice sheet and alpine glaciations related to Andean uplift,which caused a marked climatic contrast between its western and eastern flanks since the Last Glacial Maximum(LGM). The regional rock mass strength and precipitation gradient acted as a controlling factor in the glacial cirque distribution and sizes, as well as in the development of glaciation types. We report new radiocarbon dates associated with warm/dry to cold/wet climatic changes during the middle Holocene, when former small alpine glaciers were located in the uppermost section of the SBMR basins, and eventually converged to form a small ice field or a composite valley glacier at lower elevations.This can be explained by an estimated regional temperature drop of 3.8°C±0.8°C, based on a 585±26m Equilibrium Line Altitude(ELA) descent, inferred by geomorphological evidence and the Accumulation Area Ratio(AAR), in addition to a free-air adiabatic lapse rate. Subsequently, the glaciers receded due to climatic factors including a rise in temperature, as well as non-climatic factors, mainly the glacier bedrock topography.展开更多
Rice is the main staple food of the vast majority of Sierra Leoneans, eaten on a daily basis by almost every household in the country. Rice is the most important food crop widely grown by farmers across the country. A...Rice is the main staple food of the vast majority of Sierra Leoneans, eaten on a daily basis by almost every household in the country. Rice is the most important food crop widely grown by farmers across the country. Although much attention is now focused on rice production through the small holder commercialization programme (SHCP), less attention has been given to investigating the constraints faced by rice producers in the country. Also, as food insecurity continues to be a major development problem across the country, thereby undermining people’s health, productivity, and often their very survival;this study contributes to efforts to overcome the development challenges posed by food insecurity necessarily begin with accurate assessment of influential factors that constrained the production of the staple food, rice. The main objective of this study is therefore to analysis the factors that influence rice production in the country, and specifically examine the relationship between rice production and the price of rice as sold in the domestic market. The study used a log linear model with the quantity of rice produced as the dependent variable and the price of domestic rice, quantity of rice imported and price of imported rice as explanatory. Findings indicated that, domestic rice is more expensive than imported rice per ton, and this underscores the argument that, rice importation is undermining domestic rice production as a viable income generating activity. Also, almost all the people in the capital city which hosts about 70% of the total population of country prefer eating imported rice, since it is free from stones and other impurities. However, In order to control price and still increase rice production, the government should be able to purchase the rice from the farmers and then sell this rice to private retailers.展开更多
Rapid recovery of pioneer shrub and forest patch cover can reduce soil erosion, nutrient runoff and degradation of stream habitats, and promote small mammal and avian biodiversity following stand-replacing wildfires. ...Rapid recovery of pioneer shrub and forest patch cover can reduce soil erosion, nutrient runoff and degradation of stream habitats, and promote small mammal and avian biodiversity following stand-replacing wildfires. Landsat imagery from the past 25+ years was analyzed to understand patterns and rates of vegetation recovery, focusing on high burn severity (HBS) patches, within wildfire areas dating from the late 1940s in the Sierra-Nevada region of California. Normalized difference vegetation index (NDVI) levels indicative of recovered woody cover within HBS areas were analyzed starting in 1985 to quantify regrowth of patch dynamics. Analysis of landscape metrics showed that the percentage of total HBS area comprised by the largest patch of recovered woody cover was relatively small in all fires that occurred since 1995, but increased rapidly with time since fire. Patch complexity of recovered woody cover decreased notably after more than 50 years of regrowth, but was not readily associated with time for fires that occurred since the mid 1990s. Patch complexity of dense woody cover was consistently high in fires after 1995 and increased with the elevation of HBS areas. The aggregation level of patches with recovery of woody cover increased steadily with time since fire. The study approach using satellite remote sensing can be expanded to assess the consequences of stand-replacing wildfires in all forests of the region.展开更多
文摘Food safety and hygiene practices require a multisectoral approach including food, water, sanitation, waste management, transport, education, trade, policies and programs that enable safe food preparation, storage and service. Unsafe food can cause illness keeping people from achieving their full potential and death. This was a descriptive study that uses a mixed method approach to derive insights into the characteristics of food vendors related to demography, knowledge, practices, infrastructure, compliance and recommendation for a policymaking framework. Using the Lemeshows’ sample size formula, 473 vendors from formal (restaurants) and informal (cookri-baffa/table top) sites were interviewed and observed. We found from discussions that respondents had a good understanding on how to keep food safe. However, observed practices were poor 93% handled food with their bare hands, 83% did not cover their hair, and 76% did not wear an apron whilst handling, preparing or serving food, 61% did not keep their finger nails clean or short and 57% did not wash their hand before preparing or serving food. Over half (51%) had access to a toilet but 32% reported their use required payment and emphasized their poor condition/inadequate management. Nearly half (47%) of the vending sites did not have a handwashing facility, with soap and water available. Only 7% reported having any authority oversight of food safety. Food safety and hygiene practices in most cookri shops and restaurants was ‘poor’ with very limited surveillance system in place by competent authorities for compliance of food operators. Hand washing, clean surroundings, and covered food were the most common and emphasized practices to mitigate the risks associated with unsafe food.
文摘Investigations into the Andean orocline revealed a counterclockwise rotation of about 37° in the north and a clockwise rotation of about 29° in the south. This rotation would have started in the Eocene because the Nazca and South American plates converged. The transition zone between the Puna and the Sierras Pampeanas has a clockwise rotation pattern. Our new data show that the NE convergence of the Nazca and South American plates caused the counterclockwise rotation around the NW end of the Sierras Pampeanas. The temperature rise during a magmatic activity at 13 Ma would have favored a counterclockwise rotation of the mountain blocks of about 20° on a detachment zone within 10 to 15 km of depth. These range rotations generated local stress tensors trending NE and NW, facilitating the development of valleys, basins, mineralized dikes, mineral deposits, and alluvial fans separated from their origin. The Atajo fault shows both ductile and brittle characteristics. A mylonitic belt from the Sierra de Aconquija was juxtaposed on the rocks of the Ovejería Block and the Farallón Negro Volcanic Complex by reverse vertical displacement, and a dextral horizontal component of displacement resulted in curvatures that gave rise to pull-apart basins and step over features. The Santa Maria Valley, Campo del Arenal, Hualfín Valley, and Pipanaco salt flat most likely constituted a vast early Miocene basin rarely interrupted by low feature relief.
文摘Food safety, nutrition, health and wellbeing are inextricably linked. This study investigated the environmental, awareness and practices amongst both food vendors and consumers in and around Freetown the capital of Sierra Leone. The population of the area has vastly out-grown the infrastructure laid down before and since independence. De-centralization of authority to local councils as recommended post-war has only been partial. The role of local versus central government in the planning and maintenance of water, sanitation and market-infrastructure and related policies was explored. This is a qualitative study that used semi-structured interviews with vendors, consumers and 29 key informants. Amongst an estimated population of 5386 actors in food services a sample size of 309 vendors, consumers in and around the 12 busiest market hubs in Western Area Urban and Rural Districts were sampled. Most of the respondents described “food safety” as “good-to-eat, well taken care-off, and free from germs”. The respondents cited that main causes to unsafe food are poor hygienic practices: 38%, contamination by flies: 28%, uncovered food/ improper handling/poor personal hygiene: 21%, and environmental factors, such as improper refuse disposal: 11%. Respondents expressed that consuming unsafe foods can lead to diarrhoea: 34%, food poisoning: 24%, vomiting: 17%, stomach ache/pain: 16%, or typhoid: 9%. Various measures to improve food safety were cited as hand washing: 60%, cleaning surroundings: 57%, covering food: 56%, washing utensils: 52%, covering hair: 42% and using a face mask: 32%. However almost 76% of food vendors interviewed were trading near gutters, where muddy/dirty water settled, with slippery floors, discarded plastic waste, flies and inadequate water, sanitation, and/or storage facilities. None of the food vendors had had any formal training on food safety. Despite progress recently made in solid and liquid waste management during the “Transform Freetown” agenda much more improvement in infrastructure and behaviour change is required. Similarly, despite improvements in formal market facilities the pattern of informal street trading remains the most prevalent especially for the poor. The link between “safe food” and good health was only partially understood, whilst the widespread application of recommended practices to reduce risks was lacking due in part to inadequate infrastructure. As the importance of food safety becomes better understood by administrators and the public the investments required in infrastructure and social and behavioural change will contribute towards a healthier environment and outcomes.
文摘Rainfall and temperature are the important variables that are often used to trace climate variability and change. A Perception study and analysis of climatic data were conducted to assess the changes in rainfall and temperature and their impact on crop production in Moyamba district, Sierra Leone. For the perception study, 400 farmers were randomly selected from Farmer-Based Organizations (FBOs) in 4 chiefdoms and 30 Agricultural Extension Workers (AWEs) in the Moyamba district were purposely selected as respondents. Descriptive statistics and Kendall’s test of concordance was used to analyze the data collected from the farmers and AEWs. Data for the analysis of variability and trends of rainfall and temperature from 1991 to 2020 were obtained from the Sierra Leone Meteorological Agency and Njala University and grouped into monthly, seasonal and annual time series. Regression analyses were used to determine the statistical values and trend lines for the seasonal and annual time series data. The Mann-Kendall test and Sen’s Slope Estimator were used to analyze the significance and magnitude of the trends respectively. The results of both studies show evidence of climate change in the Moyamba district. A substantial number of farmers and AEWs perceived a decrease in the annual rainfall amount, length of the rainy season, a late start and end of the rainy season, an increase in the temperature during the day and night, and a shortened harmattan period over the last 30 years. Analysis of the meteorological data shows evidence of variability in the seasonal and annual distribution of rainfall and temperature, a decreasing and non-significant trend in the rainy season and annual rainfall and an increasing and significant trend in seasonal and annual temperature from 1991 to 2020. However, the observed changes in rainfall and temperature by the farmers and AEWs partially agree with the results of the analyzed meteorological data. The majority of the farmers perceived that;adverse weather conditions have negatively affected crop production in the district. Droughts, high temperatures, and irregular rainfall are the three major adverse weather events that farmers perceived to have contributed to a substantial loss in the yields of the major crops cultivated in the district. In response to the negative effects of adverse weather events, a substantial number of farmers take no action due to their lack of knowledge, technical or financial capacity to implement climate-sensitive agricultural (CSA) practices. Even though few farmers are practicing some CSA practices on their farms, there is an urgent need to build the capacity of farmers and AEWs to adapt to and mitigate the negative impacts of climate change. The most priority support needed by farmers is the provision of climate-resilient crop varieties whilst the AEWs need training on CSA practices.
文摘In this study,the Radio Direction Finding method is proposed for the detection of electromagnetic signals,in the VLF band,to try to anticipate the occurrence of potentially destructive geophysical events.The experimentation concerns the interception of electromagnetic anomalies in Sierra Leone,in the five-day time window,associated with seismic events that could potentially generate tsunamis.The area of investigation is Sierra Leone,whose coastline is subjected to tidal wave hazards triggered by earthquakes generated in the Mid-Atlantic Ridge.Although Sierra Leone is not affected by recurrent earthquakes,there is nevertheless a low probability,estimated at 2 percent,of the occurrence of destructive earthquakes in the next 50 years.Also in estimates,the risk of rogue and potentially damaging waves is estimated to strike the Sierra Leone coast at least once in the next 10 years.The Radio Direction Finding experiment carried out continuously 24/7,has shown a close relationship between increased radio-anomalies,in the frequencies of 6,000 Hz,a time window between electromagnetic anomaly detection and the imminence of an earthquake,and higher frequency times for the risk of earthquake occurrence in the Mid-Atlantic Ridge.
基金supported by grants from the National Key Research and Development Plan of China [2016TFC1202700,2016YFC1200903,and 2017YFC1200503]the China Mega‐Project for Infectious Disease [2017ZX10302301‐004,2017ZX100101,and 2017ZX10104001]
文摘Objective People in Western Africa suffer greatly from febrile jaundice, which is caused by a variety of pathogens. However, yellow fever virus(YFV) is the only pathogen under surveillance in Sierra Leone owing to the undeveloped medical and public health system there. Most of the results of YFV identification are negative. Elucidation of the pathogen spectrum is required to reduce the prevalence of febrile jaundice. Methods In the present study, we used Ion Torrent semiconductor sequencing to profile the pathogen spectrum in archived YFV‐negative sera from 96 patients in Sierra Leone who presented with unexplained febrile jaundice. Results The most frequently identified sequencing reads belonged to the following pathogens: cytomegalovirus(89.58%), Epstein‐Barr virus(55.21%), hepatitis C virus(34.38%), rhinovirus(28.13%), hepatitis A virus(20.83%), coxsackievirus(10.42%), Ebola virus(8.33%), hepatitis E virus(8.33%), lyssavirus(4.17%), leptospirosis(4.17%), chikungunya virus(2.08%), Crimean‐Congo hemorrhagic fever virus(1.04%), and hepatitis B virus(1.04%). Conclusion The distribution of sequencing reads suggests a broader spectrum of pathogens for consideration in clinical diagnostics and epidemiological surveillance in Sierra Leone.
文摘The Sierra Norte de Puebla, Mexico, has a record of hundreds of mass removal processes triggered by rainfall, where the intensity and duration of the rain are the main mechanisms. In order to determine threshold values for precipitation as a cause of a landslide, the prior, marginal and conditional probabilities were calculated. A Bayesian method was used for one-dimensional (precipitation intensity) and two-dimensional (precipitation intensity and duration) analysis. This suggested a high probability of mass movement when the precipitation exceeds 60 mm within ten days. A proposed warning system is based on classes in which the threshold is exceeded.
基金supported by a China Mega-Project for Infectious Disease(2011ZX10004-101,2012ZX10004215)Major Program of the National Natural Science Foundation of China(81590763)a SKLID Development Grant(2012SKLID102)
文摘Ebola virus disease reemerged in Western Africa in 2014.Chinese Center for Disease Control and Prevention dispatched the first Ebola virus(EBOV)detection team to run newly established Sierra Leone-China Friendship Biological Safety Laboratory.The aims of study were to understand epidemiology,clinical manifestations and survival time of EBOV in patient's blood.A total of 913specimens were tested between March 11 and April20, 2015. EBOV positivity occurred in 7.37% of the blood and 0.53% in throat swabs.
文摘The impact of summer cattle grazing on water quality during three very different climatic years in the Sierra Nevada was investigated. Water year 2009 had near normal precipitation;2010 had late precipitation and snowmelt;and 2011 had 150% above normal precipitation. Surface waters were tested for pathogenic bacteria indicators fecal coliform, E. coli, and total coliform before and after cattle were released onto summer grazing allotments. Water samples were collected from meadow stream sites up to 6 weeks before and up to 6 weeks after cattle grazing began. Streams passing through ungrazed meadow served as controls. Eight sample sites were between 1694 m and 2273 m in elevation;one site was lower at 1145 m in elevation. Samples were transported within 6 hours to a water analysis laboratory, where samples were analyzed following standardized laboratory methods. Results showed that individual site and total mean concentrations of E. coli in surface waters were within regulatory standards before cattle arrived during each of the 3 study years. After the beginning of grazing, mean E. coli counts increased as follows: 2009 from 8 to 240 CFU/100mL, 2010 from 7 to 561 CFU/10mL;2011 from 7 to 657 CFU/100mL (p < 0.05 all years). Total coliform bacteria and fecal coliform concentrations showed the same pattern. This study shows that cattle grazing in the high elevation Sierra Nevada results in a significant increase in indicator bacteria. This impact on the watersheds occurs despite widely variable annual climatic conditions.
文摘Ensuring availability and sustainable management of water and sanitation for all by 2030 is Goal 6 of the Sustainable Development Goals (SDGs). Since developing countries especially in Africa would struggle to meet this target, this study was conceived. Hence, the study was designed to assess the water quality for physiochemical parameters around a mined out site in southern Sierra Leone with the view to determine their levels, determine related associations among indicators and explore environmental forensic options. A finite population correction factor was used to identify fifty (50) groundwater sources from one hundred and fifty two (152) in nine (9) sections of Moriba Town, in Moyamba District, Sierra Leone which constitute the sample size. The study assessed sixteen (16) physical and chemical indicators across the defined boundary of the sample size. Results indicated that almost 80% of all the indicators were in good agreement with water quality standards with the exception of three. Turbidity correlated strongly with , Al and ?and almost all other indicators did not show meaningful association. High values with significant variance of water quality indicators of physical to chemical ratio were observed for pH, temperature, electrical conductivity (EC) and total dissolved solids (TDS) but no such observation was noted for turbidity. On the whole, the water quality was judged to be good, although more pro active actions were encouraged by the local people and the mining company so as to reduce contamination in some areas.
文摘Rice is the main food of Sierra Leoneans and an important source of employment and income for rural communities. According to the West African Rice Development Association report, annual consumption of rice is amongst the highest in SubSaharan Africa(SSA), 104 kg. Mainly, small scale farmers who are resource poor on both the upland and various lowlands grow rice. Sierra Leone has not been able to produce enough rice to meet its local consumption demand for a very long time now. 530 000 MT of milled rice is the required consumption need of the Sierra Leonean population per annum. In 2007, national paddy rice production was projected at 638 000 MT. The level of rice self-sufficiency rose from 50.57% in 2002 to 62.15% in 2006 and then to 63.49% in 2007. The remainder must be imported at increasingly expensive prices in the current situation of high food prices, which includes rice. The price of rice has seen a steady increase in the entire country. What most affected by this, is the low-income urban and peri-urban households. The promotion of domestic rice production is therefore a key element in the strategies for improving rice self-sufficiency, stimulating economic growth and increasing rural income. Therefore, supporting rice production programme is the only solution to pull the country out of the worsening rice situation and maintain the present trend in rice self-sufficiency. Therefore, having an understanding of the strategic interventions in rice production in Sierra Leone is an important ingredient in the promotion and attainment of rice self-sufficiency.
文摘In a bid to enhance the integrity and health of selected network of ecosystems and effectively manage them in Sierra Leone, a baseline assessment of butterfly diversity of two wetland ecosystems Mamunta Mayosso Wildlife Santuary (MMWS) and Sierra Leone River Estuary (SLRE) affected by different environmental stressors was undertaken as part of the Sierra Leone Wetland Conservation Project (SLWCP). We hypothesised that different environmental stressors affect butterfly communities in wetlands in Sierra Leone and the higher the stress the lower the butterfly diversity in an area. Sampling was conducted via field identification by wing patterns, flight mode, direct counts along transects and charaxes trapping. A total of 2300 individuals representing 95 species of butterflies were recorded. Though butterflies were evenly distributed at both sites, MMWS recorded the highest richness and abundance of butterflies during both seasons. This observation is reported to be because of high environmental stressors such as mining, agriculture and pollution from factories in the SLRE. The results further show that MMWS is made up of a mosaic of different vegetation patches that support higher diversity of butterfly species. This study also reveals that anthropogenic activities have a negative impact on butterfly diversity.
文摘The glacial morphology of southern South American presents invaluable evidence to reconstruct former glacier behaviour and its relation to climate and environmental changes. However, there are still spatial and temporal gaps in the reconstruction of the Holocene Patagonian glacial landscape. Here we present the first geomorphological record for the Sierra Baguales Mountain Range(SBMR), forming the eastern foothills of the Southern Patagonian Andes 200 km from the Pacific coast. This area is topographically isolated from the Southern Patagonian Ice Field(SPIF), and is affected by the Westerly Winds. The study area shows evidence of ice sheet and alpine glaciations related to Andean uplift,which caused a marked climatic contrast between its western and eastern flanks since the Last Glacial Maximum(LGM). The regional rock mass strength and precipitation gradient acted as a controlling factor in the glacial cirque distribution and sizes, as well as in the development of glaciation types. We report new radiocarbon dates associated with warm/dry to cold/wet climatic changes during the middle Holocene, when former small alpine glaciers were located in the uppermost section of the SBMR basins, and eventually converged to form a small ice field or a composite valley glacier at lower elevations.This can be explained by an estimated regional temperature drop of 3.8°C±0.8°C, based on a 585±26m Equilibrium Line Altitude(ELA) descent, inferred by geomorphological evidence and the Accumulation Area Ratio(AAR), in addition to a free-air adiabatic lapse rate. Subsequently, the glaciers receded due to climatic factors including a rise in temperature, as well as non-climatic factors, mainly the glacier bedrock topography.
文摘Rice is the main staple food of the vast majority of Sierra Leoneans, eaten on a daily basis by almost every household in the country. Rice is the most important food crop widely grown by farmers across the country. Although much attention is now focused on rice production through the small holder commercialization programme (SHCP), less attention has been given to investigating the constraints faced by rice producers in the country. Also, as food insecurity continues to be a major development problem across the country, thereby undermining people’s health, productivity, and often their very survival;this study contributes to efforts to overcome the development challenges posed by food insecurity necessarily begin with accurate assessment of influential factors that constrained the production of the staple food, rice. The main objective of this study is therefore to analysis the factors that influence rice production in the country, and specifically examine the relationship between rice production and the price of rice as sold in the domestic market. The study used a log linear model with the quantity of rice produced as the dependent variable and the price of domestic rice, quantity of rice imported and price of imported rice as explanatory. Findings indicated that, domestic rice is more expensive than imported rice per ton, and this underscores the argument that, rice importation is undermining domestic rice production as a viable income generating activity. Also, almost all the people in the capital city which hosts about 70% of the total population of country prefer eating imported rice, since it is free from stones and other impurities. However, In order to control price and still increase rice production, the government should be able to purchase the rice from the farmers and then sell this rice to private retailers.
文摘Rapid recovery of pioneer shrub and forest patch cover can reduce soil erosion, nutrient runoff and degradation of stream habitats, and promote small mammal and avian biodiversity following stand-replacing wildfires. Landsat imagery from the past 25+ years was analyzed to understand patterns and rates of vegetation recovery, focusing on high burn severity (HBS) patches, within wildfire areas dating from the late 1940s in the Sierra-Nevada region of California. Normalized difference vegetation index (NDVI) levels indicative of recovered woody cover within HBS areas were analyzed starting in 1985 to quantify regrowth of patch dynamics. Analysis of landscape metrics showed that the percentage of total HBS area comprised by the largest patch of recovered woody cover was relatively small in all fires that occurred since 1995, but increased rapidly with time since fire. Patch complexity of recovered woody cover decreased notably after more than 50 years of regrowth, but was not readily associated with time for fires that occurred since the mid 1990s. Patch complexity of dense woody cover was consistently high in fires after 1995 and increased with the elevation of HBS areas. The aggregation level of patches with recovery of woody cover increased steadily with time since fire. The study approach using satellite remote sensing can be expanded to assess the consequences of stand-replacing wildfires in all forests of the region.