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Farmers＇ Coping Mechanisms for Common Bean Production under Water-Logged Soil Conditions in Uganda-Rwanda Boarder Region

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Journal of Environmental Science and Engineering(B) 2013年第1期2卷 46-52页

作者： Cyamweshi Rusanganwa Athanase john steven tenywa Moses tenywa Makooma john James Okiror Dusengemungu Leonidas Mutimura Mupenzi Musoni Augustine Department of Natural Resource Management and Mechanization Rwanda Agriculture Board (RAB) Kigali 5016 Rwanda Department of Agricultural Production College of Agricultural and Environmental Sciences Makerere University Kampala 7062 Uganda Department of Extension and Innovation Studies College of Agricultural and Environmental Sciences Makerere University Kampala 7062 Uganda

Common bean （Phaseolus vulgaris L.） is a staple food and income crop in eastern Africa, especially within the Uganda-Rwanda boarder region where it constitutes a major component of food security. Unfortunately, bush beans are severely affected by frequent water-logging which persists over a considerable period of the year. In spite of this, farmers have continued to cultivate bush bean though with miserable yields. The study aimed to identify farmers＇ indigenous coping mechanisms to the climatic predicament, as a foundation for nurturing and subsequently designing appropriate management strategies for improved bean production in the region. A household survey was conducted in Kisoro district, in a location representative of the ecological conditions of Uganda-Rwanda region. 96 respondents were selected randomly at village level from a list of 500 households provided by the extension workers. Data were collected using semi-structured interviews. Findings showed that farmers possess vital coping mechanisms including construction of ridges, fertiliser application and chemical control of pests and diseases to expedite plant growth, and construction of drainage channels. It is clear that farmers＇ indigenous coping mechanisms need further nurturing and refining to improve their performance in dealing with water-logging crisis in the region.

关键词： Ridges manure drainage channels bush bean.

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Hepatic angiotensin-converting enzyme 2 expression in metabolic dysfunction-associated steatotic liver disease and in patients with fatal COVID-19

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World Journal of Gastroenterology 2024年第31期30卷 3705-3716页

作者： Angus K Jacobs steven D Morley Kay Samuel Katie Morgan Lyndsey Boswell Timothy J Kendall David A Dorward Jonathan A Fallowfield Peter C Hayes john N Plevris Hepatology Laboratory University of EdinburghEdinburgh EH164SBUnited Kingdom Scottish National Blood Transfusion Service Jack Copland CentreEdinburgh EH144BEUnited Kingdom Institute for Regeneration and Repair University of EdinburghEdinburgh EH164UUUnited Kingdom Edinburgh Pathology University of EdinburghEdinburgh EH164SBUnited Kingdom

BACKGROUND Metabolic dysfunction-associated steatotic liver disease(MASLD),characterised by hepatic lipid accumulation,causes inflammation and oxidative stress accompanied by cell damage and *** injury(LI)is also frequently reported in patients hospitalised with coronavirus disease 2019(COVID-19),while preexisting MASLD increases the risk of LI and the development of COVID-19-associated *** of injury at the cellular level remain unclear,but it may be significant that severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)which causes COVID-19,uses angiotensin-converting expression enzyme 2(ACE2),a key regulator of the‘anti-inflammatory’arm of the renin-angiotensin system,for viral attachment and host cell *** To determine if hepatic ACE2 levels are altered during progression of MASLD and in patients who died with severe *** ACE2 protein levels and localisation,and histological fibrosis and lipid droplet accumulation as markers of MASLD were determined in formalin-fixed liver tissue sections across the MASLD pathological spectrum(isolated hepatocellular steatosis,metabolic dysfunction-associated steatohepatitis(MASH)+/-fibrosis,end-stage cirrhosis)and in post-mortem tissues from patients who had died with severe COVID-19,using ACE2 immunohistochemistry and haematoxylin and eosin and picrosirius red staining of total collagen and lipid droplet areas,followed by quantification using machine learning-based image pixel *** ACE2 staining is primarily intracellular and concentrated in the cytoplasm of centrilobular hepatocytes and apical membranes of bile duct ***,ACE2 protein levels are elevated in non-fibrotic MASH compared to healthy controls but not in the progression to MASH with fibrosis and in ***2 protein levels and histological fibrosis are not associated,but ACE2 and liver lipid droplet content are significantly correlated across the MASLD *** A

关键词： Metabolic dysfunction-associated steatotic liver disease Angiotensin-converting enzyme 2 Immunohistochemistry COVID-19 COVID-19-associated cholangiopathy

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Development,validation,and transportability of several machine-learned,non-exercise-based VO_(2max)prediction models for older adults

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Journal of Sport and Health Science 2024年第5期13卷 611-620页

作者： Benjamin T.Schumacher Michael J.LaMonte Andrea Z.LaCroix Eleanor M.Simonsick steven P.Hooker Humberto Parada Jr. john Bellettiere Arun Kumar Herbert Wertheim School of Public Health and Human Longevity Science University of California San DiegoLa JollaCA 92093USA Department of Epidemiology and Environmental Health School of Public Health and Health ProfessionsUniversity at BuffaloState University of New YorkBuffaloNY 14214USA Translational Gerontology Branch Intramural Research ProgramNational Institute on AgingNational Institutes of HealthBaltimoreMD 21225USA College of Health and Human Services San Diego State UniversitySan DiegoCA 92182USA Division of Epidemiology and Biostatistics School of Public HealthSan Diego State UniversitySan DiegoCA 92182USA University of California San Diego Moores Cancer Center La JollaCA 92093USA Computer Science and Engineering and Halicioglu Data Science Institute University of California San DiegoLa JollaCA 92093USA

Background:There exist few maximal oxygen uptake(VO_(2max))non-exercise-based prediction equations,fewer using machine learning(ML),and none specifically for older *** direct measurement of VO_(2max)is infeasible in large epidemiologic cohort studies,we sought to develop,validate,compare,and assess the transportability of several ML VO_(2max)prediction ***:The Baltimore Longitudinal Study of Aging(BLSA)participants with valid VO2_(max)tests were included(n=1080).Least absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine(SVM)algorithms were trained to predict VO_(2max)*** developed these algorithms for:(a)the overall BLSA,(b)by sex,(c)using all BLSA variables,and(d)variables common in aging ***,we quantified the associations between measured and predicted VO_(2max)and ***:The age was 69.0±10.4 years(mean±SD)and the measured VO_(2max)was 21.6±5.9 mL/kg/*** absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine yielded root mean squared errors of 3.4 mL/kg/min,3.6 mL/kg/min,3.4 mL/kg/min,3.6 mL/kg/min,and 3.5 mL/kg/min,*** quartiles of measured VO_(2max)showed an inverse gradient in mortality *** VO_(2max)variables yielded similar effect estimates but were not robust to ***:Measured VO_(2max)is a strong predictor of *** ML can improve the accuracy of prediction as compared to simpler approaches but estimates of association with mortality remain sensitive to *** studies should seek to reproduce these results so that VO_(2max),an important vital sign,can be more broadly studied as a modifiable target for promoting functional resiliency and healthy aging.

关键词： Cardiorespiratory fitness Prediction algorithms Epidemiology Mortality

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Heavy Metal Bioaccumulation by Maize Grown on a Ferralsol Amended with Urban-Based Biosolid Wastes

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Journal of Agricultural Chemistry and Environment 2021年第2期10卷 184-195页

作者： Emmanuel Ntambi Muhammad Ntale john Stephen tenywa Department of Chemistry Faculty of Science Mbarara University of Science & Technology Mbarara Uganda Department of Chemistry College of Natural Sciences Makerere University Kampala Uganda Department of Agricultural Production College of Agriculture & Environmental Sciences Makerere University Kampala Uganda

Organic waste materials as soil amendments are one of the topical approaches applauded for achieving sustainable agriculture world-over. The objective of this study was to investigate the effect of urban-based biosolid waste (UBBW) application on heavy metals (Cr, Cu, Zn and Pb) bioaccumulation by maize (Zea mays L.) plants. A pot experiment was conducted three times, using an acid Ferralsol from Makerere University Agricultural Research Institute, Kabanyolo (MUARIK) in Uganda. Treatments included the application of three types of UBBW, namely sewage, brewery and abattoir, each applied independently at the rates of 0, 50 and 100 g per pot filled with 4 kg soil. This was equivalent to 0, 2.5 and 5.0 metric tonnes of dry materials per hectare. Phosphorus fertiliser was also applied at 0, 0.795 and 1.591 g P per pot, equivalent to rates of 0, 25 and 50 kg P ha-1. The brewery waste applied at rates ≥ 2.5 t·ha-1 and phosphorus at 25 kg P ha-1 resulted in shoot Cu concentrations below the World Health Organisation (WHO) safe limit (73.3 mg·kg-1);and Zn slightly above the WHO safe limit (99.4 mg·kg-1). In contrast, the concentrations of chromium in the maize plants were well above the WHO safe limit (2.3 mg·kg-1), irrespective of the applied type of UBBW. Shoot metal bioaccumulation followed the order zinc > copper > chromium, with Pb being below the detection limit. The safest UBBW was abattoir waste;while the least environmentally suitable was sewage waste. It is clear that irrespective of the type of UBBW, their application to Ferralsol causes less bioaccumulation of Pb and Cr in maize plants compared to Zn and Cu.

关键词： Lead Copper Zinc Chromium Zea mays

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Sorption and Desorption Phenomena of Urban Biowaste-Based Heavy Metals by a Ferralsol

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Journal of Agricultural Chemistry and Environment 2020年第1期9卷 13-26页

作者： Emmanuel Ntambi john Stephen tenywa Muhammad Ntale Department of Chemistry Faculty of Science Mbarara University of Science & Technology Mbarara Uganda Department of Agricultural Production College of Agriculture & Environmental Sciences Makerere University Kampala Uganda Department of Chemistry College of Natural Sciences Makerere University Kampala Uganda

Background: The objective of this study was to examine the adsorption-de- sorption phenomena of heavy metals in an agricultural Ferralsol treated with sewage solid waste at rates usually applied for soil fertility management. Methods: The study was carried out under laboratory conditions, using a Ferralsol sourced from Makerere University Agricultural Research Institute, Kabanyolo (MUARIK). Soil and sewage solid waste were analysed for pH, organic matter, cation exchange capacity and heavy metals (copper, zinc, chromium and lead). Soil was treated with sewage solid waste at input rates of 0, 50, 100, and 150 g per pot (equivalent to 0, 2.5, 5.0 and 7.5 metric tones·ha﹣1?respectively);and supplemented with phosphorus. The phosphorus was applied at rates of 0, 0.795, 1.591 and 2.385 g per pot (equivalent to 0, 25, 50 and 75 kg·ha﹣1, respectively). Batch adsorption was used to study the sorption-desorption of heavy metals on the treated soil and the Langmuir and Freundlich models were used to analyse the data. Results: Adsorption and desorption isotherms fitted better to Freundlich equation than Langmuir model. Chromium was the most sorbed and retained metal;while lead was the least retained overall. The desorption process was virtually irreversible, considering the low amounts of the metals desorbed. Chromium fitted relatively better to both models than the copper, zinc and lead. All the four metals were less desorbed at high metal concentrations. Conclusion: The four metals would not be available at high metal concentrations especially when the application rate used is ≥ 5.0 tones·ha﹣1 of the sewage solid waste. Thus, the metals would not be available for plant uptake and the chance to contaminate groundwater is very limited especially for chromium.

关键词： Heavy Metals Sewage Solid Waste Ferralsol Sorption-Desorption

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Reaction of Ferralsol to Acidifying Effect of Nitrogen Fertilisation

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Journal of Agricultural Chemistry and Environment 2021年第1期10卷 69-79页

作者： john Stephen tenywa Jean Bosco Ngarukiyimana Alice Amoding Katushabe College of Agricultural and Environmental Sciences Makerere University Kampala Uganda

Background: The objective of this study was to determine the short-term effect of urea fertiliser application on soil reactions in a Ferralsol, with particular thrust on P sorption. Methods: Two experiments were conducted for this purpose: 1) a screenhouse pot experiment; and 2) a laboratory P sorption component. The pot (10 litre capacity plastic pots) experiment was conducted at the Makerere University Agricultural Research, Kabanyolo in Uganda, using a Ferralsol. The study comprised of four urea N (46% N) fertiliser treatments, namely, 0, 40, 80 and 120 kg N·ha-1, equivalent to 0, 200, 400 and 600 mg N per pot. A completely randomised design was adopted with three replicates. Urea rates were applied in 50% split doses, one at planting and the other at 19 days after seedling emergence (to simulate farmer practice). This was followed by watering to field capacity using distilled water. Soil samples were taken at three daily intervals until day fourteen;thereafter, soil sampling was at an interval of seven days. The second urea split dose was applied at 21 days followed by soil sampling at an interval of three days till day fourteen. Thereafter, soil was sampled at seven day intervals until the end of experiment. Soil samples were analysed for exchangeable H+, Al3+, NH4+and NO3- ions. The reaction trends of the concentrations of these ions and Bray 1 P were used to structure different response curves repres

关键词： Urea Hydrolysis Ammonification Phosphorus Sorption

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Interpreting atomization of agricultural spray image patterns using latent Dirichlet allocation techniques

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Artificial Intelligence in Agriculture 2020年第1期4卷 253-261页

作者： Hongfei Li steven Cryer john Raymond Lipi Acharya Department of Statistics University of Illinois at Urbana-ChampaignChampaignILUSA Data Science Corteva AgriscienceIndianapolisINUSA

Breakup patterns of agricultural formulations are explored using unsupervised learning techniques to elucidate themechanics of atomization for oil-in-water *** researchers have shown these formulations succumb to a different breakup mechanism than conventional formulations,beginning with inhomogeneities within the liquid sheet that nucleate holes within the material being sprayed,beginning themechanism responsible for breaking the sheet into *** Latent Dirichlet Allocation(LDA),a Bayesian hierarchical model,is used to explore unsupervised learning relationships between image analysis metrics on spray video data and the resulting atomization droplet *** factors discovered by LDA were used for classification of video segments and achieved 99.9%accuracy(3-fold cross validation).Seventy-five videos were used for regression where each video had a unique measured droplet size distribution(D10,D50,and D90 values)for *** using the features learnt by Latent Dirichlet Allocation used with regression have extremely good results(R^2~0.995 in 3-fold cross validation,R^2~0.963 on never-seen videos),which serves as evidence for the potential use of this model in image analysis of agricultural spray *** has huge potential in both learning and predicting atomization patterns[e.g.,driftable fines(drops<150μm)]when used with images based on the breakup phenomena in agricultural *** small drop sizes that occur during atomization have the greatest propensity for off-target movement through wind induced *** proved useful in characterizing current and future formulation designs using only images as witnessed by observations and excellent predictions summarized in this *** fact,thesemethods offer potential for use under field conditions to address spray performance based upon images of spray patterns at the nozzle without the need for expensive light scattering equipment often used to measure this phenomenon

关键词： atomization formulation image

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Genetic variability of the stable fly assessed on a global scale using amplified fragment length polymorphism

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Insect Science 2016年第5期23卷 695-703页

作者： Kathleen M Kneeland steven R. Skoda john E. Foster Department of Entomology 103 Entomology Haft University of Nebraska-Lincoln Lincoln NE 68583 USDA-ARS-KBUSLIRL Screwworm Research Unit 2700 Fredericksburg Road Kern/ille TX 78028 USA

The stable fly, Stomoxys calcitrans （L.）（Diptera： Muscidae）, is a blood-feeding, economically important pest of animals and humans worldwide. Improved management strategies are essential and their development would benefit from studies on genetic di- versity of stable flies. Especially if done on a global scale, such research could generate information necessary for the development and application of more efficient control meth- ods. Herein we report on a genetic study of stable flies using amplified fragment length polymorphism, with samples of 10-40 individuals acquired from a total of 25 locations in the Nearctic, Neotropic, Palearctic, Afrotropic and Australasian biogeographical regions. We hypothesized that genetic differentiation would exist across geographical barriers. Although Fsx （0.33） was moderately high, the Gsx （0.05; representing genetic diversity between individuals） was very low; Nm values （representing gene flow） were high （9.36）. The mismatch distribution and tests of neutrality suggested population expansion, with no genetic differentiation between locations. The analysis of molecular variance （AMOVA） results showed the majority of genetic diversity was within groups. The mantel test showed no correlation between geographic and genetic distance; this strongly supports the AMOVA results. These results suggest that stable flies did not show genetic differentiation but are panmictic, with no evidence of isolation by distance or across geographical barriers.

关键词： AFLP biting flies external parasites genetic diversity livestock pests Stomoxys calcitrans

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History and evaluation of national-scale geochemical data sets for the United States

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Geoscience Frontiers 2013年第2期4卷 167-183页

作者： David B.Smith steven M.Smith john D.Horton U.S.Geological Survey.Denver Federal Center MS 973.DenverCO 80225USA

Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United *** earliest of these,here termed the ＇Shacklette＇ data set,was generated by a U.S. Geological Survey（USGS） project conducted from 1961 to *** project used soil collected from a depth of about 20 cm as the sampling medium at 1323 sites throughout the conterminous *** National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance（NUREHSSR） Program of the *** of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in both the conterminous *** *** sampled area represented about 65%of the *** Natural Resources Conservation Service（NRCS）,from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous *** data set contains analyses of more than 3000 *** National Geochemical Survey,a USGS project conducted from 1997 to 2009,used a subset of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the *** covered by the NURE-HSSR *** data set contains chemical analyses for more than 70,000 *** USGS,in collaboration with the Mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in *** of three horizons or depths at more than 4800 sites in the *** completed in 2010,and chemical analyses are currently *** NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the *** data set currently contains data from more than 1400 *** paper（1） discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and（2） evaluates each data set in terms

关键词： Geochemical mapping National-scale geochemical data Geochemical baselines United States

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Phosphate Sorption Characteristics of Andosols of the Volcanic Highlands of Central African Great Lakes Region

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Journal of Environmental Science and Engineering(A) 2013年第2期2卷 89-96页

作者： Cyamweshi Rusanganwa Athanase john steventenywa Peter Ebanyat Moses tenywa Makooma Athanase Mukuralinda Athanase Nduwumuremyi Department of Natural Resource Management and Mechanization Rwanda Agriculture Board (RAB) Kigali 5016 Rwanda Department of Agricultural Production College of Agricultural and Environmental Sciences Makerere University Kampala 7062Uganda World Agroforestry Centre (ICRAF) Butare 227 Rwanda

High phosphate sorption constitutes a critical impediment to agricultural use of Andosols in the volcanic highlands of Central African Great Lakes region. A laboratory experiment was conducted on soil samples collected from an Andosol amended with a factorial combination of lime and P （phosphorus） fertiliser to determine the P sorption characteristics and derive parameter estimates relevant in the prediction and management of P in the Andosols. The potential for sorption of additional P and its binding intensity were evaluated by applying the two-surface Langmuir model to sorption isotherms. The calculated P sorption maxima ranged from 1,667 mg·kg^-1 to 10,000 mg·kg^-1 representing about 95% of the P applied to the soil. The external P requirement ranged from 1,492 mgP·kg^-1 to 2,760 *** which is further evidence that the studied Andosols are high P sorbers. There was no significant effect of lime and P rates on P sorption capacity of the Andosols. Exchangeable iron was highly correlated with P sorption maxima b2 （r = 0.98） on the high energy sites, whereas cation exchange capacity was negatively correlated with P sorption maxima bl （r = 0.999） and positively correlated with P binding energy K1 （r = 0.998） on the low energy sites.

关键词： Phosphate sorption capacity external P requirement two-surface Langmuir model

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