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Impact on Soil Organic C and Total Soil N from Cool- and warm-Season legumes Used in a Green Manure-Forage Cropping System

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Agricultural Sciences 2024年第3期15卷 333-357页

作者： Clark B. Neely francis M. Rouquette Jr. Cristine l.S. Morgan Frank M. Hons william l. Rooney Gerald R. Smith Department of Soil and Crop Science Washington State University Pullman WA USA Texas A&M Agrilife Research Overton TX USA Chief Scientific Officer Soil Health Institute Morrisville NC USA Department of Soil and Crop Science Texas A&M University College Station TX USA

Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their seasonal biomass production can be managed to complement forage grasses. Our research objectives were to evaluate both warm- and cool-season annual forage legumes as green manure for biomass, N content, ability to enhance soil organic carbon (SOC) and soil N, and impact on post season forage grass crops. Nine warm-season forage legumes (wSl) were spring planted and incorporated as green manure in the fall. Forage rye (Secale cereale l.) was planted foll.w.ng the incorporation of wSl treatments. Eight cool-season forage legumes (CSl) were fall planted in previously fall.w.plots and incorporated as green manure in late spring. Sorghum-sudangrass (Sorghum bicolor x Sorghum bicolor var. sudanense) was planted over all treatments in early summer after forage rye harvest and incorporation of CSl treatments. Sorghum-sudangrass was harvested in June, August and September, and treatments were evaluated for dry matter and N concentration. Soil cores were taken from each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm, and soil C and N were measured using combustion analysis. Nylon mesh bags containing plant samples were buried at 15 cm and used to evaluate decomposition rate of above ground legume biomass, including change in C and N concentrations. Mungbean (Vigna radiata l. [wilczek]) had the highest shoot biomass yield (6.24 t DM ha-1) and contributed the most total N (167 kg∙ha-1) and total C (3043 kg∙ha-1) of the wSl tested. Decomposition rate of wSl biomass was rapid in the first 10 weeks and very sl.w.afterward. winter pea (Pisum sativum l. spp. sativum), arrow leaf clover (Trifolium vesiculosum Savi.), and crimson clover (Trifolium incarnatum l.) were the most productive CSl in this trial. Austrian winter pea

关键词： Annual legumes Soil N Soil Organic C Green Manure Deer Browse Forage Cropping Systems

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Effects of Feeding Programs Based on One or Two Milk Replacer Daily Meals on Growth, Solid Feed Intake and Rumen Fermentation and Development of Dairy Calves

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Agricultural Sciences 2015年第12期6卷 1428-1440页

作者： Christine Julien Corine Bayourthe Caroline lacroux francis Enjalbert Université de Toulouse INPT ENSAT UMR1388 Génétique Physiologie et Systèmes d’Elevage Castanet-Tolosan France INRA UMR1388 Génétique Physiologie et Systèmes d’Elevage Castanet-Tolosan France UMR INRA ENVT 1225 Interactions H&#244te Agent Pathogène Ecole Nationale Vétérinaire de Toulouse 23 Chemin des Capelles Toulouse France Université de Toulouse INPT ENVT UMR1388 Génétique Physiologie et Systèmes d’Elevage Toulouse France

Sixteen Holstein calves were used to study the effects of two feeding programs (FP) on growth, intake, rumen development and ruminal metabolism from birth to weaning. Two feeding programs based on milk replacer (MR) were tested: a once a day (OAD) MR (200 g/l) distribution vs. a standard twice a day (TAD) MR (125 g/l) distribution. All calves received water, wheat straw and a starter concentrate ad libitum. Four calves per group were slaughtered at weaning and rumen epithelium from the ventral sac was sampled for papillae (RP) density. Results showed that the FP had no effect on body weight of calves and total feed intake. From day 42 to day 56, ruminal pH was l.w.r (P = 0.036) and ruminal oxydo-reducing potential.w.s higher (P = 0.001) in OAD than TAD calves. Ruminal total volatile fatty acid (VFA) concentrations did not significantly differ between FP. From day 21 to day 63, butyrate ruminal concentration was significantly higher in OAD than TAD calves (5.17 vs 3.95 mmol/l). This probably explained the higher development of RP in calves fed once daily. Finally, the tested feeding system based on a once daily MR distribution affects the concentrate feeding pattern of calves.

关键词： Dairy Calves Milk Replacer Feeding Frequency Oxydo-Reducing Potential Rumen Development

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Relations among Sap Fl.w. Soil Moisture, weather, and Soybean Plant Parameters in High water Demand and Final Growth Stages

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Agricultural Sciences 2019年第3期10卷 371-385页

作者： Mukhammadzakhrab Ismanov Paul francis Christopher Henry leonel Espinoza Department of Crop Soil and Environmental Sciences University of Arkansas Fayetteville AR USA

The dynamics of sap fl.w.in relation to plant morphology and weather conditions during reproductive growth of soybean (Glycine max. l. Merr.) influence decisions pertaining to efficient irrigation management and other inputs for high yields. Field studies began in 2017 at Marianna, Arkansas to measure moisture dynamics of soybeans during seed fill (R5 to R7) using heat balance stem fl.w.gauges. Sap fl.w.was highly correlated to solar radiation with maximum rates observed during beginning seed fill (R5). A solar radiation efficiency (SRE) value, calculated as hourly sap fl.w.rate per watt-hour of solar radiation (g/wh2), is proposed. The SRE relates to crop water demand and hydraulic resistance of the soil-root-stem-leaf-pod-seed pathway. SRE values ranged from 0 - 1.2 g/wh2. Soil moisture, growth stage, time of day, and weather conditions influenced the SRE, with higher values observed in the morning, late afternoon, and during R5 growth. Peak sap fl.w. of 39 g/h at R5, 25 g/h at R6, and 3 g/h at R7 occurred. The ratio of measured sap fl.w.to estimated crop evapotranspiration was 0.9 to 1.3 during R5 to R6.9 (maximum dry matter), but dropped to 0.2 at R7. Further research is needed to better understand late season reproductive moisture dynamics in soybeans.

关键词： Sap Flow Growth Stage Evapotranspiration Soil Moisture Solar Radiation Soil water water Resistance Plant water Use

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Hemodialysis patients’ satisfaction and associated factors in National Teaching Hospital Hemodialysis Center, Cotonou (Benin)

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Open Journal of Nephrology 2019年第4期9卷 127-138页

作者： Séraphin Ahoui Jacques Vigan Bruno léopold Agboton Evariste Eteka francis Tchegnonsi Tognon A. Anselme Djidonou Prosper Gandaho leonard Fourn Department of Nephrology Borgou Regional Teaching Hospital Parakou Benin Nephrology-Hemodialysis University Clinic (CUNH) Hubert Koutoukou Maga National Teaching Hospital Cotonou (CNHU-HKM) Benin Department of Psychiatry Borgou Regional Teaching Hospital Parakou Benin Faculty of Health Sciences University of Abomey-Calavi Abomey-Calavi Benin

Background: Patients’ satisfaction is a relevant component in assessing healthcare services. The objective of this study was to study the level of satisfaction of chronic hemodialysis patients and the associated factors in Cotonou CNHU-HKM dialysis center. Patients and Methods: It was a cross-sectional, descriptive and analytical study conducted by administering a questionnaire on days off dialysis. It was carried out from 1st November 2015 to 1st January 2016 in CNHU-HKM Nephrology University Clinic of Cotonou. Hemodialysis patients aged 18 years and above having given their informed consent were included in the study. Patients’ recruitment was comprehensive. likert scale was used in assessing the level of satisfaction with 4 as “very satisfied” and 1 for “very dissatisfied”. Satisfaction was evaluated on the basis of ware dimensions. The threshold for satisfaction was 50. Outcomes: Overall, 377 patients were included in the study. Respondents’ mean age was 51.5 ± 13.3 years with 1.37 as sex ratio. Arteriovenous fistula was used for 80.1% of hemodialysis patients. 77.7% of the patients underwent dialysis twice a week while 45.9% were administered a four-hour dialysis. The overall average proportion of “satisfied” was 76.5%. The level of satisfaction was 52% for healthcare environment, 61% for service delivery, 73.9% for healthcare accessibility, 76.1% for healthcare structure, 77.5% for healthcare management, 90.3% for quality of healthcare, 88.3% for interpersonal relationship and 93.2% for efficiency and continuum of healthcare. Factors associated with satisfaction included age (p = 0.02), vascular access (p = 0.04) and urea reduction ratio (p = 0.01). In addition, the degree of satisfaction of hemodialysis patients was not statistically associated with sex, marital status, educational level, history of the disease, age of dialysis, number of sessions per week, and duration per session. Conclusion: The overall level of hemodialysis patients’ satisfaction is above

关键词： Satisfaction Chronic Hemodialysis Cotonou

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legume Green Manure and Intercropping for High Biomass Sorghum Production

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Agricultural Sciences 2024年第6期15卷 605-621页

作者： Clark B. Neely francis M. Rouquette Jr. Cristine l. S. Morgan Frank M. Hons william l. Rooney Gerald R. Smith Department of Soil and Crop Science Washington State University Pullman WA USA Texas A&M Agrilife Research Overton TX USA Soil Health Institute Morrisville NC USA Department of Soil and Crop Science Texas A&M University College Station TX USA

Before the advent of cheap, synthetic fertilizers, legumes were commonly used as green manure crops for their ability to fix atmospheric nitrogen (N). A three-year study at Overton, TX examined legume integration into high-biomass sorghum (Sorghum bicolor l.) production systems on a lilbert loamy fine sand recently cultivated after a fertilized bermudagrass [Cynodon dactylon (l.) Pers.] pasture. In this split-split plot design, ‘Dixie’ crimson clover (Trifolium incarnatum l.) and ‘Iron and Clay’ cowpea (Vigna unguiculata l.) were integrated into a high-biomass sorghum production system to evaluate impacts on N concentration, C concentration, and yield of high-biomass sorghum and their impacts on soil total N and soil organic carbon (SOC). Main plots were split into crimson clover green manure (ClGM) and winter fall.w.(FAll) foll.w.d by three sub-plots split into warm-season crop rotations: cowpea green manure (CPGM), cowpea-sorghum intercrop (CPSR), and sorghum monocrop (SORG). Three N fertilizer treatments (0, 45, 90 kg N∙ha−1) were randomized and applied as sub-sub plots. The ClGM increased (P sorghum biomass yield (16.5 t DM∙ha−1) 28% in year three but had no effect in the first two years. The CPSR treatment reduced sorghum yield up to 62% compared to SORG;whereas CPGM increased sorghum yield 56% and 18% the two years foll.w.ng cowpea incorporation. Rate of N fertilizer had no effect on sorghum biomass yield. Decrease in SOC and soil N over time indicated mineralization of organic N and may explain why no N fertilizer response was observed in sorghum biomass yield. Cowpea showed strong potential as a green manure crop but proved to be too competitive for successful intercropping in high-biomass sorghum production systems.

关键词： High-Biomass Sorghum legumes Green Manure Intercrop Cowpea Crimson Clover Soil Organic Carbon Soil Nitrogen

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Applications of multi-nuclear magnetic resonance spectroscopy at 7T

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world Journal of Radiology 2011年第4期3卷 105-113页

作者： Mary C Stephenson Frances Gunner Antonio Napolitano Paul l Greenhaff Ian A MacDonald Nadeem Saeed william Vennart Susan T francis Peter G Morris The Sir Peter Mansfield Magnetic Resonance Centre School of Physics and AstronomyUniversity of Nottingham School of Biomedical Sciences University of Nottingham Medical School Academic Radiology University of Nottingham Molecular Medicine PfizerSandwich

AIM: To discuss the advantages of ultra-high field (7T) for 1H and 13C magnetic resonance spectroscopy (MRS) studies of ***: Measurements of brain metabolites were made at both 3 and 7T using 1H MRS. Measurements of glycogen and lipids in muscle were measured using 13C and 1H MRS ***: In the brain, increased signal-to-noise ratio (SNR) and dispersion all.w. spectral separation of the amino-acids glutamate, glutamine and γ-aminobutyric acid (GABA), without the need for sophisticated editing sequences. Improved quantification of these metabolites is demonstrated at 7T relative to 3T. SNR was 36% higher, and measurement repeatability (% coefficients of variation) was 4%, 10% and 10% at 7T, vs 8%, 29% and 21% at 3T for glutamate, glutamine and GABA respectively. Measurements at 7T were used to compare metabolite levels in the anterior cingulate cortex (ACC) and insula. Creatine and glutamate levels were found to be significantly higher in the insula compared to the ACC (P le, the increased SNR and spectral resolution at 7T enables interleaved studies of glycogen (13C) and intra-myocellular lipid (IMCl) and extra-myocellular lipid (EMCl) (1H) foll.w.ng exercise and re-feeding. Glycogen levels were significantly decreased foll.w.ng exercise (-28% at 50% VO2 max; -58% at 75% VO2 max). Interestingly, levels of glycogen in the hamstrings foll.w.d those in the quadriceps, despite reduce exercise loading. No changes in IMCl and EMCl.w.re found in the ***: The demonstrated improvements in brain and muscle MRS measurements at 7T will increase the potential for use in investigating human metabolism and changes due to pathologies.

关键词： Magnetic resonance spectroscopy 13C 1H 7 Tesla Glutamate Glutamine γ-aminobutyric acid

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Quantitative Estimation of γ-Glutamylethylamide in Commercially Available Made Teas [Camellia sinensis (l.) O. Kuntze, Theaceae] in Kenya

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American Journal of Plant Sciences 2016年第1期7卷 55-62页

作者： Janet Too John wanyoko Thomas Kinyanjui Kelvin Moseti francis wachira Department of Chemistry Egerton University Njoro Kenya Kenya Agricultural and livestock Research Organization Tea Research Institute Kericho Kenya Association for Strengthening Agricultural Research in East and Central Africa Entebbe Uganda

A study was carried out to quantitatively estimate the l-theanine content in 19 teas commercially available in the Kenyan market by High Performance liquid Chromatography (HPlC). The test tea samples analyzed were green (n = 4), black (n = 8) and flavored (n = 7) teas from different origins viz., Kenya (n = 4), Uganda (n = 2), Tanzania (n = 5), Rwanda (n = 4), Cameroon (n = 1) and Sri-lanka (n = 2) commercially available in the Kenyan market. The estimated limit of Detection (lOD) of the current method was 0.01% l-theanine. The l-theanine content ranged from bel.w.the detection limit (l-theanine) to 1.60% l-theanine on a dry weight (d.w) basis. Statistically significant differences (p were observed in the l-theanine contents of black, green and flavoured teas. Rwandan green tea contained the highest l-theanine content with 1.60% d.w. whereas six of the seven flavoured teas had very l.w.theanine levels (ld not be quantified by the current method.

关键词： Food Analysis Food Composition HPlC l-Theanine Non-Protein Amino Acids Tea

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Performance Survey of PVC Insulation of lC/Gecamines Electrical Cables Subjected to Ageing and Its life Span Evaluation

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world Journal of Engineering and Technology 2022年第4期10卷 728-737页

作者： Chungu Mwana Mwamba Yannick Michael Kabangu Ngoie Muliangala Mbalaba francis Kasambay Mutangala francis Katamea Mwanvua Mavé Twite Kabamba Edmond lukozi Mufaume Donatien Metallurgy and Materials Department Faculty of Polytechnics University of Lubumbashi Lubumbashi Democratic Republic of the Congo Independent Researcher Faculty of Polytechnics University of Lubumbashi Lubumbashi Democratic Republic of the Congo

Considering the insulators ageing in a mixture of PVC and dye, set foll.w.ng operating conditions and time to ensure proper operation and perfect safety of industrial installations using insulated conductors. The results showed that the insulation carried out by the l.C main office was a good quality (on thermal aspect), because the resistance of the insulation is so high (i.e. 3940 Mega Ohms under normal conditions). The results showed a lifespan of 50 years at a temperature of 40°C (close to ambient temperature), plus minus 33 years at a temperature of 70°C;plus minus 22 years at a temperature of 100°C and 12 years at a temperature of 160°C. Furthermore, information on chemical attack, the results showed that PVC cables have poor resistance to sulfuric acid attack (having a pH of 1.5 and a density of 1.84 g/cm3). lC/Gecamines is able to produce locally a good quality of electrical cables.

关键词： PVC Performance Thermal Ageing Chemical Resistance Cable life Span

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沸石咪唑酯骨架-67高效催化l-丙交酯的开环聚合反应

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应用化学 2019年第4期36卷 414-422页

作者：朱晨阳罗志雄陈宬 Chaemchuen Somboon Verpoort francis 武汉理工大学材料科学与工程学院武汉430070 武汉理工大学材料复合新技术国家重点实验室武汉430070

为了探究沸石咪唑酯骨架材料(Zeolitic Imidazolate Frameworks,ZIFs)结构中的金属单元对其催化活性的影响,我们采用室温法合成了ZIF-8、Zn/Co-ZIF和ZIF-67,并用其催化l-丙交酯的本体开环聚合反应。在相同的反应条件下,ZIF-67具有最高... 详细信息

为了探究沸石咪唑酯骨架材料(Zeolitic Imidazolate Frameworks,ZIFs)结构中的金属单元对其催化活性的影响,我们采用室温法合成了ZIF-8、Zn/Co-ZIF和ZIF-67,并用其催化l-丙交酯的本体开环聚合反应。在相同的反应条件下,ZIF-67具有最高的催化活性。与2-甲基咪唑(配体)作为催化剂相比,ZIF-67催化得到的聚乳酸具有高度全同立构结构。此外,基质辅助激光解吸-飞行时间(MAlDI-TOF)质谱表明,ZIF-67催化得到的聚乳酸主要为线状结构。经过3次循环反应后,ZIF-67的催化活性没有明显降低。

关键词：开环聚合反应聚乳酸沸石咪唑酯骨架-67 非均相催化

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Testing of Decision Making Tools for Village land Use Planning and Natural Resources Management in Kilimanjaro Region

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Open Journal of Soil Science 2014年第13期4卷 446-458页

作者： Anthony Z. Sangeda Frederick C. Kahimba Reuben A. l. Kashaga Ernest Semu Christopher P. Mahonge francis X. Mkanda Sokoine University of Agriculture Morogoro Tanzania Sustainable land Management Project Regional Commissioner’s Office Moshi Tanzania

This paper focuses on participatory testing of decision making tools (DMTs) at village level to assist in development of land use plans (lUPs) for sustainable land management (SlM) in Kilimanjaro Region, Tanzania. Data were collected using conditional surveys through key informant interviews with the project’s district stakeholders in each district, focused group discussions with selected villagers and participatory mapping of natural resources. Soil health, land degradation, carbon stock, and hydrological conditions were assessed in the seven pilot villages in all seven districts using DMTs as part of testing and validation. Results indicated soils of poor to medium health, and land degradation as portrayed by gullies and wind erosion in l.w.ands and better in uplands. Carbon and forest disturbance status could not be assessed using one-year data but hydrological analysis revealed that water resources were relatively good in uplands and poor in the l.w.ands. Challenges with regard to land use include increased gully erosion, decreased stream fl.w. reduced vegetation cover due to shifting from coffee with tree sheds to annual crops farming, cultivation near water sources, and overgrazing. Empowering the community with decision making tools at village level is essential to ensure that village land uses are planned in a participatory manner for sustainable land and natural resources management in Kilimanjaro and other regions in Tanzania.

关键词： Decision Making Tool land Use Planning Sustainable land Management Natural Resources Management Kilimanjaro

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