Sairme mineral water, one of the famous mineral waters in Georgia, is renowned for its exceptional healing properties. The distinctiveness and therapeutic benefits of the naturally sourced mineral water, known as “Sa...Sairme mineral water, one of the famous mineral waters in Georgia, is renowned for its exceptional healing properties. The distinctiveness and therapeutic benefits of the naturally sourced mineral water, known as “Sairme”, stem from its rich array of microelements, notably including iron and manganese. Since 1948, the bottling of Sairme mineral water has been a prominent activity. Named after the Sairme deposit, this mineral water is packaged in various formats to cater to diverse consumer preferences. The bottling process involves transporting the mineral water from wells to the bottling plant through pipelines. Prior to bottling, the mineral water undergoes meticulous processing stages in adherence to current Georgian and international regulations. This process ensures that the concentration of trace elements in the bottled water is minimized, maintaining its purity and quality. Given the importance of preserving the microelements present in bottled mineral water, our research is dedicated to optimizing the technological process. Our objective is to safeguard the valuable microelements while ensuring the highest standards of quality and safety in the final product.展开更多
It was found earlier that moisture content (MC) of intact kernels of grain and nuts could be determined by Near Infra Red (NIR) reflectance spectrometry. However, if the MC values can be determined while the nuts are ...It was found earlier that moisture content (MC) of intact kernels of grain and nuts could be determined by Near Infra Red (NIR) reflectance spectrometry. However, if the MC values can be determined while the nuts are in their shells, it would save lot of labor and money spent in shelling and cleaning the nuts. Grain and nuts absorb low levels of NIR, and when NIR radiation is incident on them, a substantial portion of the radiation is reflected back. Thus, studying the NIR reflectance spectra emanating from in-shell peanuts, an attempt is made for the first time to determine the MC of in-shell peanuts. In-shell peanuts of two different market types, Virginia and Valencia, were conditioned to different moisture levels between 6% and 26% (wet basis), and separated into calibration and validation groups. NIR absorption spectral data from 1000 nm to 2500 nm in 1 nm intervals were collected from both groups. Measurements were obtained on 30 replicates within each moisture level. Reference MC values for each moisture level in these groups were obtained using standard air-oven method. Partial Least Square (PLS) analysis was performed on the calibration data, and prediction models were developed. The Standard Error of Calibration (SEC), and R2 of the calibration models were computed to select the best calibration model. The selected models were used to predict the moisture content of peanuts in the validation sets. Predicted MC values of the validation samples were compared with their standard air-oven moisture values. Goodness of fit was determined based on the lowest Standard Error of Prediction (SEP) and highest R2 value obtained for the prediction models. The model, with reflectance plus normalization spectral data with an SEP of 0.74 for Valencia and 1.57 for Virginia type in-shell peanuts was selected as the best model. The corresponding R2 values were 0.98 for both peanut types. This work establishes the possibility of sensing MC of intact in-shell peanuts by NIR reflectance method, and would be useful for the peanut and allied industries.展开更多
Fugitive dust is one of the well known problems in agriculture and it affects both humans and machine producing quality. Dust problems can seriously cause harmful diseases to workers and ruin expensive equipments. In ...Fugitive dust is one of the well known problems in agriculture and it affects both humans and machine producing quality. Dust problems can seriously cause harmful diseases to workers and ruin expensive equipments. In this study, a dust formation generated in open environment by vehicles was analyzed on unpaved roads. Formed dust was measured by calculating total forces on the PM10 (airborne particles smaller than 10 mm) of dust particles, such as air velocity, gravity forces and air turbulence generated by the moving vehicle. The water fogger nozzle discharge was measured to determine the approximate droplets quantity in the air. The foggers were used to suppress the generated dust in an open environment via installing a proposed automatic suppression system which opens automatically when vehicles pass under the system. The relationship between water droplet speed and ability of collecting fugitive dust showed that high air temperature above 40oC and wind speed above 10 m s-1 have negative effects on the system’s ability of collecting dust due to evaporation of small radius droplets and/or drifting water droplets away from the effective area. The overall system efficiency was found to be 85% and the proposed dust suppression system was found to be a satisfying solution for reducing fugitive dust hazards.展开更多
Oil exploitation in many African countries is associated with litigation and conflicts to water and soil pollution. It is because of inadequate planning for management of oil spills and industrial effluents in environ...Oil exploitation in many African countries is associated with litigation and conflicts to water and soil pollution. It is because of inadequate planning for management of oil spills and industrial effluents in environmentally sustainable manner. Uganda’s natural resources such as soils and water bodies are threatened by contamination due to rapid industrialization and rural-urban migration in established Industrial Business Parks and planned oil and gas production at Albertine Graben Region. The low level of compliance to industrial effluents discharge standards relevant to specific environmental receptors and activities within oil and gas sector development pose a big question of how to sustain the biodiversity and natural resource management. Experiences from elsewhere have shown bioremediation as a viable and proven option to provide potentially manageable solutions to resulting pollution as a substitute to modern well-known remediation methods, for it is relatively cheaper, more efficient and minimal toxic byproducts after treatment. The most used bioremediation agents in different studies reviewed are bacterial species especially Pseudomonas and Bacillus, followed by Aspergillus a fungi species, microalgae and aquatic plants such as duckweed, macrophytes and pteridophytes. Regardless of the waste produced in either oil and gas sector or industries, these agents have shown greater biodegradation rates. Pseudomonas sp. has a degradation efficiency of oil compounds ranging from 90% - 100%, and Aspergillus sp. 75% - 95%. Some aquatic plants can thrive in created wetlands with relatively still water such as Phragmites australis which can degrade hydrocarbons especially Aromatic compounds with benzene ring up to 95%. It can thrive in salty water with high pH range of 4.8 - 8.2. With industrial wastewater, algae is the most dominant with the degradation rates varying from 65% -100% and bacteria at 70% - 90%. Most of the reported results are in the developed country context. In developing countries, duckweed is reported as the commonest aquatic plant in wastewater treatment for removal of heavy metals because it is more tolerant to a wide range of environmental conditions and produce biomass faster. It has a removal rate of heavy metals between 90% and 100%. Basing on literature data analysis, bacteria are more suitable for treating water from oil pollution using Pseudomonas sp. Phragmites australis is suited for cleaning up oil in both water and soil. Duckweed is the best in treating water polluted with industrial effluents. This paper presents the different bioremediation methods that Uganda can potentially apply to mitigate the increased risk of environmental pollutions from planned industrialization and oil and gas development in the Albertine Graben Region.展开更多
This study is aimed at evaluating alternative designs of waste stabilization ponds (WSPs) and constructed wetlands (CWs) for Kaputiei Housing Estate consisting of 2000 low cost housing units in Kenya. The entire analy...This study is aimed at evaluating alternative designs of waste stabilization ponds (WSPs) and constructed wetlands (CWs) for Kaputiei Housing Estate consisting of 2000 low cost housing units in Kenya. The entire analysis was carried out by simulating the effectiveness and purification efficiencies of WSPs and CWs in terms of Biological Oxygen Demand (BOD) reduction and faecal coliform (FC) removal under different scenarios of water treatment systems that included Re-sizing of the initial sewage treatment system, optimizing the design of the initial system and design of hybrid system for the estate. The graphic comparison of the simulated parameters under different scenarios showed that a hybrid design that combines both the WSPs and CWS provides an effluent BOD of 20 mg/l and 195 FC per 100 ml that meets the standard effluent discharge that is acceptable for unrestricted crop irrigation and thus will be reused in the housing estate for kitchen gardening and agroforestry.展开更多
This research aims at using a dynamic model of tractor system to support navigation system design for an automati- cally guided agricultural tractor. This model, consisting of a bicycle model of the tractor system, ha...This research aims at using a dynamic model of tractor system to support navigation system design for an automati- cally guided agricultural tractor. This model, consisting of a bicycle model of the tractor system, has been implemented in the MATLAB environment and was developed based on a John Deere tractor. The simulation results from this MATLAB model was validated through field navigation tests. The accuracy of the trajectory estimation is strongly affected by the determination of the cornering stiffness of the tractor. In this simulation, the tractor cornering stiffness analysis was identified during simulation analysis using the MATLAB model based on the recorded trajectory data. The obtained data was used in simulation analyses for various navigation operations in the field of interest. The analysis on field validation test results indicated that the developed tractor system could accurately estimate wheel trajectories of a tractor system while operating in agricultural fields at various speeds. The results also indicated that the developed system could accurately determine tractor velocity and steering angle while the tractor operates in curved fields.展开更多
Objective:To assess the degree of anxiety,depression and stress due to the COVID-19 epidemic among healthcare professionals in Sri Lanka.Methods:Healthcare professionals from 6 selected government and private hospital...Objective:To assess the degree of anxiety,depression and stress due to the COVID-19 epidemic among healthcare professionals in Sri Lanka.Methods:Healthcare professionals from 6 selected government and private hospitals located in Gampaha District were recruited for the study.The socio-demographic factors,knowledge and attitudes of healthcare professionals on COVID-19 was collected through a self-administered questionnaire,while Depression,Anxiety and Stress Scale score was used to assess the psychological wellbeing.Descriptive statistics and binary logistic regression techniques were used for data analysis.Results:Totally 324 healthcare professionals were included and the respondents had a high overall level of knowledge towards COVID-19.Twenty-five percent of the respondents had different levels of anxiety,while 10.8%had mild depression,and 4.6%had moderate depression.Interestingly,40.4%of the respondents had mild stress,and 11.1%had moderate stress.Young people(20-35 years),medical laboratory technologist and nursing officer,being quarantined,having a SARS-CoV-2-infected family member,involvement in COVID-19 patient care,and limited availability of personal protection equipment,were recognized as significant risk factors associated with anxiety,depression and stress.Conclusions:The healthcare professionals are high-risk groups to experience psychological impacts from COVID-19.Continuous monitoring and implementing appropriate intervention activities and provision of counseling support are highly recommended.展开更多
Micronutrient deficiency (MD) is a problem among schoolchildren which, in addition to other effects, also affects their intellectual abilities. Inclusion of vegetables to food formulations can help to reduce MD becaus...Micronutrient deficiency (MD) is a problem among schoolchildren which, in addition to other effects, also affects their intellectual abilities. Inclusion of vegetables to food formulations can help to reduce MD because they contain vital micronutrients which are required for improved school performance. This study aimed at evaluating acceptability, determining the nutritional quality and estimating the contribution of vegetable enriched products to the Recommended Dietary Allowance (RDA) of schoolchildren (5 to 13 years). The vegetables used were red and green amaranth leaves, orange fleshed sweet potato and pumpkin. Selection of vegetables was based on richness in micronutrients;local availability and consumption levels in Uganda;and their underutilization status particularly in processed form. Each of the vegetables was preprocessed and incorporated separately into soybean and grain amaranth in the ratio of 10:40:50, respectively, to improve the nutrient and energy density of the formulations. Sensory screening of formulations in a range of products (porridges, soups and snacks) revealed that orange fleshed sweet potato formulation was most preferred for porridge as well as for snacks (at 30:70 ratio of orange fleshed sweet potato composite to wheat flour);while red amaranth leaves composite was most preferred for soup. When tested for acceptability, nutritional quality, as well as contribution to the RDA (for vitamin A, iron, zinc, protein and energy) for schoolchildren 5 to 13 years, acceptability tests and nutritional quality of food products from the formulations were highly rated compared to commercial products (pure maize porridge, wheat based soup and 100% refined wheat flour snacks). All products from the two formulations contributed favourably to vitamin A, iron, zinc and protein requirements of children (5 to 13 years). Based on these findings, orange fleshed sweet potato composite flour can be recommended for making porridge, and can substitute (30%) for wheat flour in making snacks;while red amaranth leaf composite flour can be recommended for making soups.展开更多
Effective utilization of coffee wastes has been a great challenge in Uganda despite their wider use to replenish soil organic matter. This study explored the possibility of producing biochar from coffee husks that cou...Effective utilization of coffee wastes has been a great challenge in Uganda despite their wider use to replenish soil organic matter. This study explored the possibility of producing biochar from coffee husks that could be used as a soil amendment for replenishing soil nutrients and also for enhancement of soil water holding capacity. Pyrolysis of coffee husks was done in a batch bio-reactor under slow pyrolysis conditions of temperatures 350°C - 550°C and residence times 30 - 60 min. For easy characterization, biochar was grinded, sieved through a 1 mm sieve and then analyzed using a computerized Thermo Graphic Analyzer with an inbuilt and integrated ELTRA 84 GmbH Precision Digital weighing scale. Proximate analysis (wet basis) of biochar gave a moisture content of 5.2%, ash content of 14.7%, volatile matter of 13.2% and fixed carbon of 66.9%. Biochar was applied to soil at different rates (0%, 5%, 10% and 20% w/w) and its effect on water holding capacity was investigated. Results show that bio-char amended soils had higher water holding capacity (p ≤ 0.05) compared to biochar free soils. The water holding capacity also increased with increase in biochar amendment with a 1.5% increase in soil water holding capacity for each 1% increase in biochar application rate. Biochar was also rich in soil nutrient elements with 0.96% N, 0.39% P and 1.97% K;this increased the availability of soil nutrients for crop growth. The results suggest that biochar could be a better tool to improve soil conditions thus enhancing the sustainability of agriculture.展开更多
Napier, a fast growing and perennial grass has a dry matter (DM) yield potential of 78 tons/ha/yr. However, under water availability constraints Napier’s yield potential reduces to 62 tons/ha/yr. In an effort to atta...Napier, a fast growing and perennial grass has a dry matter (DM) yield potential of 78 tons/ha/yr. However, under water availability constraints Napier’s yield potential reduces to 62 tons/ha/yr. In an effort to attain Napier’s yield potential, irrigation management strategies have been integrated into its production to provide the highest productivity. This review assesses the effect of irrigation water management strategies on Napier productivity and also looks at future perspectives. Application of these strategies <em>i.e.</em>, precision irrigation, deficit irrigation, and application of biophysical models, can increase Napier’s yield potential to 112 tons/ha/yr. Review findings revealed that there is a need to close the knowledge gap on response of Napier productivity to different irrigation water management strategies. The future perspective explores the potential of the FAO AquaCrop model in provision of pre-season decision-making on irrigation strategies due to its relatively low cost and simplifications required in parameterization.展开更多
The study was conducted to determine the influence of gratering and fermentation parameters on the physicochemical quality of starch obtained from two cassava varieties in Sierra Leone (i.e., SLICASS 11 and SLICASS 6)...The study was conducted to determine the influence of gratering and fermentation parameters on the physicochemical quality of starch obtained from two cassava varieties in Sierra Leone (i.e., SLICASS 11 and SLICASS 6). Fresh cassava roots harvested from the Department of Agricultural Engineering were peeled, washed and grated before fermentation and starch extraction. Fermentation was carried out under separate aerobic and anaerobic conditions for a period of Seven days. Physicochemical analyses were conducted at the Postharvest Food and Bioprocess Engineering Laboratory of the Department of Agricultural and Bio-System Engineering, Njala University to determine the solubility, water absorption capacity and swelling power of starch extracts obtained from various experimental treatments. Fermentation method and duration had significant effects on the solubility, water absorption capacity (WAC) and swelling power (SP) of starch extracts. Maximum solubility and WAC were recorded on the fifth day, for both cassava varieties tested, with apparent significant difference resulting from the two gratering bands (i.e., with 1.5-inch nail hole and 4-inch nail hole sizes, respectively). While swelling power increased consistently with temperature for starch obtained from SLICASS-11 variety, an irregular pattern was observed for SLICASS-6 variety. A multiple correlation analysis proposes a significant and weak correlation between temperature, WAC (+0.150) and swelling power (+0.048). Also multiple correlation analyses suggest a significant correlation between fermentation period, the functional properties of starch extracts obtained from both fermentation methods and cassava varieties (i.e., solubility (−0.226), water absorption capacity (+0.301) and swelling power (+0.329)).展开更多
Anaerobic digestion(AD)has long been used to treat different types of organic wastes especially in the developed world.However,organic wastes are still more often considered as a waste instead of a resource in the dev...Anaerobic digestion(AD)has long been used to treat different types of organic wastes especially in the developed world.However,organic wastes are still more often considered as a waste instead of a resource in the developing world,which contributes to environmental pollution arising from their disposal.This study has been conducted at Bugolobi Sewage Treatment Plant(BSTP),where two organic wastes,cow manure and brewery sludge were co-digested with primary sludge in different proportions.This study was done in lab-scale reactors at mesophilic temperature and sludge retention time of 20 d.The main objective was to evaluate the biodegradability of primary sludge generated at BSTP,Kampala,Uganda and enhance its ability of biogas production.When the brewery sludge was added to primary STP sludge at all proportions,the biogas production rate increased by a factor of 3.This was significantly(p<0.001)higher than observed gas yield(337±18)mL/(L·d))in the control treatment containing(only STP sludge).Co-digesting STP sludge with cow manure did not show different results compared to the control treatment.In conclusion,Bugolobi STP sludge is poorly anaerobically degradable with low biogas production but co-digestion with brewery sludge enhanced the biogas production rate,while co-digestion with cow manure was not beneficial.展开更多
In recent years,government investments in implementing restrictive public policies on the treatment and discharge of effluents from the aquaculture industry have increased.Hence,efficient and cleaner methods for aquac...In recent years,government investments in implementing restrictive public policies on the treatment and discharge of effluents from the aquaculture industry have increased.Hence,efficient and cleaner methods for aquaculture production are needed.Recirculating aquaculture systems(RAS)offers water conservation by recycling the treated aquaculture water for reuse.RAS wastewater treatment using a moving bed bioreactors(MBBRs)process has been considered well suited for maintaining good water quality,thereby making fish farming more sustainable.Currently,improvements were achieved in tackling the influence of salinity,organic matter,disinfectant,and bioreactor start-up process on the MBBR performance efficiency.This review highlights an updated overview of recent development made using MBBR to treat the residual water from RAS.Precisely,nitrification and simultaneous nitrification-denitrification(SND),and other hybrid processes for nitrogen removal were elucidated.Finally,future challenges and prospects of MBBRs in RAS facilities that need to be considered were also proposed.展开更多
Electrical conductivity(EC)of soil-water extracts is commonly used to assess soil salinity.However,its conversion to the EC of saturated soil paste extracts(ECe),the standard measure of soil salinity,is currently requ...Electrical conductivity(EC)of soil-water extracts is commonly used to assess soil salinity.However,its conversion to the EC of saturated soil paste extracts(ECe),the standard measure of soil salinity,is currently required for practical applications.Although many regression models can be used to obtain ECe from the EC of soil-water extracts,the application of a site-specific model to different sites is not straightforward due to confounding soil factors such as soil texture.This study was conducted to develop a universal regression model to estimate a conversion factor(CF)for predicting EC_(e) from EC of soil-water extracts at a 1:5 ratio(EC_(1:5)),by employing a site-specific soil texture(i.e.,sand content).A regression model,CF=8.9105e^(0.0106sand)/1.2984(r^(2)=0.97,P<0.001),was developed based on the results of coastal saline soil surveys(n=173)and laboratory experiments using artificial saline soils with different textures(n=6,sand content=10%-65%)and salinity levels(n=7,salinity=1-24 dS m^(-1)).Model performance was validated using an independent dataset and demonstrated that EC_(e) prediction using the developed model is more suitable for highly saline soils than for low saline soils.The feasibility of the regression model should be tested at other sites.Other soil factors affecting EC conversion factor also need to be explored to revise and improve the model through further studies.展开更多
Plasto-Foam brand,medium size of 30 mm thickness(black and green)commonly used polyethylene bags for preparing foods were selected from those available in local markets.The polyethylene bag samples were crushed into p...Plasto-Foam brand,medium size of 30 mm thickness(black and green)commonly used polyethylene bags for preparing foods were selected from those available in local markets.The polyethylene bag samples were crushed into pieces,ashed and then acid digested to determine the concentrations of heavy metals selected(Pb,Cr,Co and Cd)using Atomic Absorption spectrophotometer.All the polyethylene samples were tested positive for heavy metals.Concentrations of heavy metals in polyethylene bags ranged from 1080 ppm to 1725 ppm,76 ppm to 112 ppm,35 ppm to 52 ppm,18 ppm to 31 ppm for Pb,Cd,Cr and Co,respectively.Forty-eight posho(Ugali)samples were prepared and wrapped in these polyethylene bags and migration studies were carried out at 65°C and 80°C.The experimental data obtained were then compared to the modeled data using the models developed by Baner et al.,and Limm and Hollifield to determine which model was a better estimator.Model fitting was done based on Non-linear least square analysis using Microsoft EXCEL 2003.Diffusion and partition coefficients both between food and the contact material were also obtained by fitting experimental data to the model equation.The modeling approaching could best describe the experimental data of the measured contaminants.The study revealed that all polyethylene bags showed highest contaminant concentration(above USFDA limit)of Pb,Cd,Cr and Co,respectively confirming the potential health risk to individuals if continuously eat food thermally prepared in polyethylene bags.展开更多
In recent years,large multifaceted spatial,temporal,and spatio-temporal databases have attained significant popularity and importance in the database community.In order to perform preliminary investigation,exploratory...In recent years,large multifaceted spatial,temporal,and spatio-temporal databases have attained significant popularity and importance in the database community.In order to perform preliminary investigation,exploratory visual analysis of such data-sets is highly desirable.To facilitate the convenient and efficient visualization,scientists and practitioners often need to convert the spatial component of the data-set into a more usable format.Though among the various formats available today in spatial data science community,Geographical Markup Language(GML)adheres to its central position and is of our interest in this work.The development of a tool to satisfy the spatial format conversion needs tailored to every user’s needs from scratch is difficult,time-consuming,and requires skills not easy to possess.We developed Auto-ConViz,to solve the issue stated above.It accepts the spatial component in GML format,converts that into shapefile format,and facilitates informative and automated interaction with the data-sets.It supports basic query and geospatial analysis and visualization tasks and offers functionalities such as zooming,panning,and feature selection.Furthermore,our software leverages navigation to classical ArcGIS software interface for users interested in more intensive analysis.AutoConViz serves both the database and geographical information system communities to explore insights of spatiotemporal databases and will help to further geospatial research and development.展开更多
文摘Sairme mineral water, one of the famous mineral waters in Georgia, is renowned for its exceptional healing properties. The distinctiveness and therapeutic benefits of the naturally sourced mineral water, known as “Sairme”, stem from its rich array of microelements, notably including iron and manganese. Since 1948, the bottling of Sairme mineral water has been a prominent activity. Named after the Sairme deposit, this mineral water is packaged in various formats to cater to diverse consumer preferences. The bottling process involves transporting the mineral water from wells to the bottling plant through pipelines. Prior to bottling, the mineral water undergoes meticulous processing stages in adherence to current Georgian and international regulations. This process ensures that the concentration of trace elements in the bottled water is minimized, maintaining its purity and quality. Given the importance of preserving the microelements present in bottled mineral water, our research is dedicated to optimizing the technological process. Our objective is to safeguard the valuable microelements while ensuring the highest standards of quality and safety in the final product.
文摘It was found earlier that moisture content (MC) of intact kernels of grain and nuts could be determined by Near Infra Red (NIR) reflectance spectrometry. However, if the MC values can be determined while the nuts are in their shells, it would save lot of labor and money spent in shelling and cleaning the nuts. Grain and nuts absorb low levels of NIR, and when NIR radiation is incident on them, a substantial portion of the radiation is reflected back. Thus, studying the NIR reflectance spectra emanating from in-shell peanuts, an attempt is made for the first time to determine the MC of in-shell peanuts. In-shell peanuts of two different market types, Virginia and Valencia, were conditioned to different moisture levels between 6% and 26% (wet basis), and separated into calibration and validation groups. NIR absorption spectral data from 1000 nm to 2500 nm in 1 nm intervals were collected from both groups. Measurements were obtained on 30 replicates within each moisture level. Reference MC values for each moisture level in these groups were obtained using standard air-oven method. Partial Least Square (PLS) analysis was performed on the calibration data, and prediction models were developed. The Standard Error of Calibration (SEC), and R2 of the calibration models were computed to select the best calibration model. The selected models were used to predict the moisture content of peanuts in the validation sets. Predicted MC values of the validation samples were compared with their standard air-oven moisture values. Goodness of fit was determined based on the lowest Standard Error of Prediction (SEP) and highest R2 value obtained for the prediction models. The model, with reflectance plus normalization spectral data with an SEP of 0.74 for Valencia and 1.57 for Virginia type in-shell peanuts was selected as the best model. The corresponding R2 values were 0.98 for both peanut types. This work establishes the possibility of sensing MC of intact in-shell peanuts by NIR reflectance method, and would be useful for the peanut and allied industries.
基金funded by the Special Program on the S&T of China for the Pollution Control and Treatment of Water Bodies(2008ZX07421-001)the Foundamental Research Funds for the Central Universities, China
文摘Fugitive dust is one of the well known problems in agriculture and it affects both humans and machine producing quality. Dust problems can seriously cause harmful diseases to workers and ruin expensive equipments. In this study, a dust formation generated in open environment by vehicles was analyzed on unpaved roads. Formed dust was measured by calculating total forces on the PM10 (airborne particles smaller than 10 mm) of dust particles, such as air velocity, gravity forces and air turbulence generated by the moving vehicle. The water fogger nozzle discharge was measured to determine the approximate droplets quantity in the air. The foggers were used to suppress the generated dust in an open environment via installing a proposed automatic suppression system which opens automatically when vehicles pass under the system. The relationship between water droplet speed and ability of collecting fugitive dust showed that high air temperature above 40oC and wind speed above 10 m s-1 have negative effects on the system’s ability of collecting dust due to evaporation of small radius droplets and/or drifting water droplets away from the effective area. The overall system efficiency was found to be 85% and the proposed dust suppression system was found to be a satisfying solution for reducing fugitive dust hazards.
文摘Oil exploitation in many African countries is associated with litigation and conflicts to water and soil pollution. It is because of inadequate planning for management of oil spills and industrial effluents in environmentally sustainable manner. Uganda’s natural resources such as soils and water bodies are threatened by contamination due to rapid industrialization and rural-urban migration in established Industrial Business Parks and planned oil and gas production at Albertine Graben Region. The low level of compliance to industrial effluents discharge standards relevant to specific environmental receptors and activities within oil and gas sector development pose a big question of how to sustain the biodiversity and natural resource management. Experiences from elsewhere have shown bioremediation as a viable and proven option to provide potentially manageable solutions to resulting pollution as a substitute to modern well-known remediation methods, for it is relatively cheaper, more efficient and minimal toxic byproducts after treatment. The most used bioremediation agents in different studies reviewed are bacterial species especially Pseudomonas and Bacillus, followed by Aspergillus a fungi species, microalgae and aquatic plants such as duckweed, macrophytes and pteridophytes. Regardless of the waste produced in either oil and gas sector or industries, these agents have shown greater biodegradation rates. Pseudomonas sp. has a degradation efficiency of oil compounds ranging from 90% - 100%, and Aspergillus sp. 75% - 95%. Some aquatic plants can thrive in created wetlands with relatively still water such as Phragmites australis which can degrade hydrocarbons especially Aromatic compounds with benzene ring up to 95%. It can thrive in salty water with high pH range of 4.8 - 8.2. With industrial wastewater, algae is the most dominant with the degradation rates varying from 65% -100% and bacteria at 70% - 90%. Most of the reported results are in the developed country context. In developing countries, duckweed is reported as the commonest aquatic plant in wastewater treatment for removal of heavy metals because it is more tolerant to a wide range of environmental conditions and produce biomass faster. It has a removal rate of heavy metals between 90% and 100%. Basing on literature data analysis, bacteria are more suitable for treating water from oil pollution using Pseudomonas sp. Phragmites australis is suited for cleaning up oil in both water and soil. Duckweed is the best in treating water polluted with industrial effluents. This paper presents the different bioremediation methods that Uganda can potentially apply to mitigate the increased risk of environmental pollutions from planned industrialization and oil and gas development in the Albertine Graben Region.
文摘This study is aimed at evaluating alternative designs of waste stabilization ponds (WSPs) and constructed wetlands (CWs) for Kaputiei Housing Estate consisting of 2000 low cost housing units in Kenya. The entire analysis was carried out by simulating the effectiveness and purification efficiencies of WSPs and CWs in terms of Biological Oxygen Demand (BOD) reduction and faecal coliform (FC) removal under different scenarios of water treatment systems that included Re-sizing of the initial sewage treatment system, optimizing the design of the initial system and design of hybrid system for the estate. The graphic comparison of the simulated parameters under different scenarios showed that a hybrid design that combines both the WSPs and CWS provides an effluent BOD of 20 mg/l and 195 FC per 100 ml that meets the standard effluent discharge that is acceptable for unrestricted crop irrigation and thus will be reused in the housing estate for kitchen gardening and agroforestry.
基金Project supported by the National Natural Science Foundation of China (No. 30270773)the Teaching and Research Award Program forOutstanding Young Teachers in Higher Education Institutions of MOE,Chinaand the Natural Science Foundation of Zhejia
文摘This research aims at using a dynamic model of tractor system to support navigation system design for an automati- cally guided agricultural tractor. This model, consisting of a bicycle model of the tractor system, has been implemented in the MATLAB environment and was developed based on a John Deere tractor. The simulation results from this MATLAB model was validated through field navigation tests. The accuracy of the trajectory estimation is strongly affected by the determination of the cornering stiffness of the tractor. In this simulation, the tractor cornering stiffness analysis was identified during simulation analysis using the MATLAB model based on the recorded trajectory data. The obtained data was used in simulation analyses for various navigation operations in the field of interest. The analysis on field validation test results indicated that the developed tractor system could accurately estimate wheel trajectories of a tractor system while operating in agricultural fields at various speeds. The results also indicated that the developed system could accurately determine tractor velocity and steering angle while the tractor operates in curved fields.
文摘Objective:To assess the degree of anxiety,depression and stress due to the COVID-19 epidemic among healthcare professionals in Sri Lanka.Methods:Healthcare professionals from 6 selected government and private hospitals located in Gampaha District were recruited for the study.The socio-demographic factors,knowledge and attitudes of healthcare professionals on COVID-19 was collected through a self-administered questionnaire,while Depression,Anxiety and Stress Scale score was used to assess the psychological wellbeing.Descriptive statistics and binary logistic regression techniques were used for data analysis.Results:Totally 324 healthcare professionals were included and the respondents had a high overall level of knowledge towards COVID-19.Twenty-five percent of the respondents had different levels of anxiety,while 10.8%had mild depression,and 4.6%had moderate depression.Interestingly,40.4%of the respondents had mild stress,and 11.1%had moderate stress.Young people(20-35 years),medical laboratory technologist and nursing officer,being quarantined,having a SARS-CoV-2-infected family member,involvement in COVID-19 patient care,and limited availability of personal protection equipment,were recognized as significant risk factors associated with anxiety,depression and stress.Conclusions:The healthcare professionals are high-risk groups to experience psychological impacts from COVID-19.Continuous monitoring and implementing appropriate intervention activities and provision of counseling support are highly recommended.
文摘Micronutrient deficiency (MD) is a problem among schoolchildren which, in addition to other effects, also affects their intellectual abilities. Inclusion of vegetables to food formulations can help to reduce MD because they contain vital micronutrients which are required for improved school performance. This study aimed at evaluating acceptability, determining the nutritional quality and estimating the contribution of vegetable enriched products to the Recommended Dietary Allowance (RDA) of schoolchildren (5 to 13 years). The vegetables used were red and green amaranth leaves, orange fleshed sweet potato and pumpkin. Selection of vegetables was based on richness in micronutrients;local availability and consumption levels in Uganda;and their underutilization status particularly in processed form. Each of the vegetables was preprocessed and incorporated separately into soybean and grain amaranth in the ratio of 10:40:50, respectively, to improve the nutrient and energy density of the formulations. Sensory screening of formulations in a range of products (porridges, soups and snacks) revealed that orange fleshed sweet potato formulation was most preferred for porridge as well as for snacks (at 30:70 ratio of orange fleshed sweet potato composite to wheat flour);while red amaranth leaves composite was most preferred for soup. When tested for acceptability, nutritional quality, as well as contribution to the RDA (for vitamin A, iron, zinc, protein and energy) for schoolchildren 5 to 13 years, acceptability tests and nutritional quality of food products from the formulations were highly rated compared to commercial products (pure maize porridge, wheat based soup and 100% refined wheat flour snacks). All products from the two formulations contributed favourably to vitamin A, iron, zinc and protein requirements of children (5 to 13 years). Based on these findings, orange fleshed sweet potato composite flour can be recommended for making porridge, and can substitute (30%) for wheat flour in making snacks;while red amaranth leaf composite flour can be recommended for making soups.
文摘Effective utilization of coffee wastes has been a great challenge in Uganda despite their wider use to replenish soil organic matter. This study explored the possibility of producing biochar from coffee husks that could be used as a soil amendment for replenishing soil nutrients and also for enhancement of soil water holding capacity. Pyrolysis of coffee husks was done in a batch bio-reactor under slow pyrolysis conditions of temperatures 350°C - 550°C and residence times 30 - 60 min. For easy characterization, biochar was grinded, sieved through a 1 mm sieve and then analyzed using a computerized Thermo Graphic Analyzer with an inbuilt and integrated ELTRA 84 GmbH Precision Digital weighing scale. Proximate analysis (wet basis) of biochar gave a moisture content of 5.2%, ash content of 14.7%, volatile matter of 13.2% and fixed carbon of 66.9%. Biochar was applied to soil at different rates (0%, 5%, 10% and 20% w/w) and its effect on water holding capacity was investigated. Results show that bio-char amended soils had higher water holding capacity (p ≤ 0.05) compared to biochar free soils. The water holding capacity also increased with increase in biochar amendment with a 1.5% increase in soil water holding capacity for each 1% increase in biochar application rate. Biochar was also rich in soil nutrient elements with 0.96% N, 0.39% P and 1.97% K;this increased the availability of soil nutrients for crop growth. The results suggest that biochar could be a better tool to improve soil conditions thus enhancing the sustainability of agriculture.
文摘Napier, a fast growing and perennial grass has a dry matter (DM) yield potential of 78 tons/ha/yr. However, under water availability constraints Napier’s yield potential reduces to 62 tons/ha/yr. In an effort to attain Napier’s yield potential, irrigation management strategies have been integrated into its production to provide the highest productivity. This review assesses the effect of irrigation water management strategies on Napier productivity and also looks at future perspectives. Application of these strategies <em>i.e.</em>, precision irrigation, deficit irrigation, and application of biophysical models, can increase Napier’s yield potential to 112 tons/ha/yr. Review findings revealed that there is a need to close the knowledge gap on response of Napier productivity to different irrigation water management strategies. The future perspective explores the potential of the FAO AquaCrop model in provision of pre-season decision-making on irrigation strategies due to its relatively low cost and simplifications required in parameterization.
文摘The study was conducted to determine the influence of gratering and fermentation parameters on the physicochemical quality of starch obtained from two cassava varieties in Sierra Leone (i.e., SLICASS 11 and SLICASS 6). Fresh cassava roots harvested from the Department of Agricultural Engineering were peeled, washed and grated before fermentation and starch extraction. Fermentation was carried out under separate aerobic and anaerobic conditions for a period of Seven days. Physicochemical analyses were conducted at the Postharvest Food and Bioprocess Engineering Laboratory of the Department of Agricultural and Bio-System Engineering, Njala University to determine the solubility, water absorption capacity and swelling power of starch extracts obtained from various experimental treatments. Fermentation method and duration had significant effects on the solubility, water absorption capacity (WAC) and swelling power (SP) of starch extracts. Maximum solubility and WAC were recorded on the fifth day, for both cassava varieties tested, with apparent significant difference resulting from the two gratering bands (i.e., with 1.5-inch nail hole and 4-inch nail hole sizes, respectively). While swelling power increased consistently with temperature for starch obtained from SLICASS-11 variety, an irregular pattern was observed for SLICASS-6 variety. A multiple correlation analysis proposes a significant and weak correlation between temperature, WAC (+0.150) and swelling power (+0.048). Also multiple correlation analyses suggest a significant correlation between fermentation period, the functional properties of starch extracts obtained from both fermentation methods and cassava varieties (i.e., solubility (−0.226), water absorption capacity (+0.301) and swelling power (+0.329)).
基金The authors wish to acknowledge the financial support from VLIR,the Belgian scholarship body and National Water and Sewerage Corporation(NWSC)for further support in Uganda.We also wish to acknowledge Henry Mugabi(EABL),Cyrus Galyaki,Nabatesa Sylvia and Chaba Charles(NWSC)for the Lab and field work support.Willy Verstraete and Korneel Rabaey acknowledge support from the Ghent University Multidisciplinary Research Partnership(MRP)“Biotechnology for a Sustainable Economy”(01 MRA 510W).
文摘Anaerobic digestion(AD)has long been used to treat different types of organic wastes especially in the developed world.However,organic wastes are still more often considered as a waste instead of a resource in the developing world,which contributes to environmental pollution arising from their disposal.This study has been conducted at Bugolobi Sewage Treatment Plant(BSTP),where two organic wastes,cow manure and brewery sludge were co-digested with primary sludge in different proportions.This study was done in lab-scale reactors at mesophilic temperature and sludge retention time of 20 d.The main objective was to evaluate the biodegradability of primary sludge generated at BSTP,Kampala,Uganda and enhance its ability of biogas production.When the brewery sludge was added to primary STP sludge at all proportions,the biogas production rate increased by a factor of 3.This was significantly(p<0.001)higher than observed gas yield(337±18)mL/(L·d))in the control treatment containing(only STP sludge).Co-digesting STP sludge with cow manure did not show different results compared to the control treatment.In conclusion,Bugolobi STP sludge is poorly anaerobically degradable with low biogas production but co-digestion with brewery sludge enhanced the biogas production rate,while co-digestion with cow manure was not beneficial.
基金This study received support from the National Key R&D Program of China(No.2020YFD0900600)the Key Program of Science and Technology of Zhejiang Province(2019C02084).
文摘In recent years,government investments in implementing restrictive public policies on the treatment and discharge of effluents from the aquaculture industry have increased.Hence,efficient and cleaner methods for aquaculture production are needed.Recirculating aquaculture systems(RAS)offers water conservation by recycling the treated aquaculture water for reuse.RAS wastewater treatment using a moving bed bioreactors(MBBRs)process has been considered well suited for maintaining good water quality,thereby making fish farming more sustainable.Currently,improvements were achieved in tackling the influence of salinity,organic matter,disinfectant,and bioreactor start-up process on the MBBR performance efficiency.This review highlights an updated overview of recent development made using MBBR to treat the residual water from RAS.Precisely,nitrification and simultaneous nitrification-denitrification(SND),and other hybrid processes for nitrogen removal were elucidated.Finally,future challenges and prospects of MBBRs in RAS facilities that need to be considered were also proposed.
基金support of the Cooperative Research Program of Agriculture Science and Technology Development,Rural Development Administration,Republic of Korea(No.PJ0138732021)。
文摘Electrical conductivity(EC)of soil-water extracts is commonly used to assess soil salinity.However,its conversion to the EC of saturated soil paste extracts(ECe),the standard measure of soil salinity,is currently required for practical applications.Although many regression models can be used to obtain ECe from the EC of soil-water extracts,the application of a site-specific model to different sites is not straightforward due to confounding soil factors such as soil texture.This study was conducted to develop a universal regression model to estimate a conversion factor(CF)for predicting EC_(e) from EC of soil-water extracts at a 1:5 ratio(EC_(1:5)),by employing a site-specific soil texture(i.e.,sand content).A regression model,CF=8.9105e^(0.0106sand)/1.2984(r^(2)=0.97,P<0.001),was developed based on the results of coastal saline soil surveys(n=173)and laboratory experiments using artificial saline soils with different textures(n=6,sand content=10%-65%)and salinity levels(n=7,salinity=1-24 dS m^(-1)).Model performance was validated using an independent dataset and demonstrated that EC_(e) prediction using the developed model is more suitable for highly saline soils than for low saline soils.The feasibility of the regression model should be tested at other sites.Other soil factors affecting EC conversion factor also need to be explored to revise and improve the model through further studies.
基金Project RU/CGS/GRG/15/10/10,the RUFORUM,Kampala,Uganda.The scientific responsibility is assumed by its authors.
文摘Plasto-Foam brand,medium size of 30 mm thickness(black and green)commonly used polyethylene bags for preparing foods were selected from those available in local markets.The polyethylene bag samples were crushed into pieces,ashed and then acid digested to determine the concentrations of heavy metals selected(Pb,Cr,Co and Cd)using Atomic Absorption spectrophotometer.All the polyethylene samples were tested positive for heavy metals.Concentrations of heavy metals in polyethylene bags ranged from 1080 ppm to 1725 ppm,76 ppm to 112 ppm,35 ppm to 52 ppm,18 ppm to 31 ppm for Pb,Cd,Cr and Co,respectively.Forty-eight posho(Ugali)samples were prepared and wrapped in these polyethylene bags and migration studies were carried out at 65°C and 80°C.The experimental data obtained were then compared to the modeled data using the models developed by Baner et al.,and Limm and Hollifield to determine which model was a better estimator.Model fitting was done based on Non-linear least square analysis using Microsoft EXCEL 2003.Diffusion and partition coefficients both between food and the contact material were also obtained by fitting experimental data to the model equation.The modeling approaching could best describe the experimental data of the measured contaminants.The study revealed that all polyethylene bags showed highest contaminant concentration(above USFDA limit)of Pb,Cd,Cr and Co,respectively confirming the potential health risk to individuals if continuously eat food thermally prepared in polyethylene bags.
文摘In recent years,large multifaceted spatial,temporal,and spatio-temporal databases have attained significant popularity and importance in the database community.In order to perform preliminary investigation,exploratory visual analysis of such data-sets is highly desirable.To facilitate the convenient and efficient visualization,scientists and practitioners often need to convert the spatial component of the data-set into a more usable format.Though among the various formats available today in spatial data science community,Geographical Markup Language(GML)adheres to its central position and is of our interest in this work.The development of a tool to satisfy the spatial format conversion needs tailored to every user’s needs from scratch is difficult,time-consuming,and requires skills not easy to possess.We developed Auto-ConViz,to solve the issue stated above.It accepts the spatial component in GML format,converts that into shapefile format,and facilitates informative and automated interaction with the data-sets.It supports basic query and geospatial analysis and visualization tasks and offers functionalities such as zooming,panning,and feature selection.Furthermore,our software leverages navigation to classical ArcGIS software interface for users interested in more intensive analysis.AutoConViz serves both the database and geographical information system communities to explore insights of spatiotemporal databases and will help to further geospatial research and development.