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Improved sprinkler irrigation layouts for smallholders

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International Journal of Agricultural and Biological Engineering 2022年第24期15卷 30-38页

作者： Saeed rad Lei Gan Junfeng Dai Shuaipu Zhang Liangliang Huang Linyan Pan Mohd Raihan taha Guilin University of Technology College of Environmental Science and EngineeringGuilin 541004China Guilin University of Technology Guangxi Collaborative Innovation Center for Water Pollution Control and Safety in Karst AreaGuilin 541004China Guangxi Key Laboratory of Environmental Pollution Control Theory&Technology Guilin University of Technology Guilin 541004China Department of Civil Engineering University Kebangsaan MalaysiaBandar Baru Bangi 43600 UKMSelangorMalaysia

Pressurized irrigation systems are economically justifiable for medium-to large-scale farms,while fewer choices are available for *** current research work provides additional options for small plots,as the only income source for low-income farmers in poorer countries,which produce a considerable portion of the agricultural products in some regions of the *** this research,two novel layouts of a semipermanent sprinkler irrigation system,namely,clock hand(CH)and corner pivot(CP)lateral designs,were designed for a lighter irrigation system to lower the cost *** new techniques were based on a quadrant/full circle movement pattern of manually pivoting laterals,with no/shorter main pipe requirements,which causes a higher system *** retrofitted layouts were examined in different farms with areas of 0.20 hm^(2),0.81 hm^(2),1.62 hm^(2),and 3.24 hm^(2) in Guangxi,*** study introduced,analyzed,and compared the layouts with the widespread traditional split lateral method on technical planning,components,implementation,operation details,size optimization,performance evaluation,and economic *** comparison with the traditional system,CH and CP were found to be more user-friendly and cost-effective but slightly complicated in design with higher required manual *** results revealed a distribution uniformity(LQDU)of 81.0%to 84.0%via the catch can method,lower capital costs(35.0%-45.0%),and lower annual expenses(6.5%-9.8%)for CP and CH,respectively,compared to the split lateral *** 0.81 hm^(2) and 1.62 hm^(2) farms were found to be the optimum farm sizes for implementation of the new methods for a 25-year project time *** outcomes of this experimental work can encourage small farm owners with limited capital to apply pressurized systems for efficient irrigation and water resource sustainability.

关键词： sprinkler irrigation layout semipermanent smallholder cost-effectiveness

radiation Doses in Diagnostic radiology and Method for Dose Reduction

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Open Journal of radiology 2023年第1期13卷 34-41页

作者： taha M. taha Hoda A. Ahmed Fathy A. Shaheen radiation Protection Department Nuclear Research Center Egyptian Atomic Energy Authority Cairo Egypt radiology Unit Medical Administration Nuclear Research Center Egyptian Atomic Energy Authority Cairo Egypt

Objective: The current research study aims to calculate entrance surface air kerma for skull, chest, cervical spine, lumbar spine, and pelvic X-ray examinations in interior posterior and posterior interior positions and generate a method for chest dose reduction to decrease radiation risk. Materials and Methods: The indirect dose measurement was used in the current research. The X-ray tube output was measured using rad-CHECK Plus ionization chamber and the indirect entrance surface air kerma was calculated via applying physical acquisition parameters such as a focus on skin distance, tube current times exposure time (mAs), and applied tube voltage (kV), and applying a mathematical model. Results: The main findings were obtained from comparing the radiation doses with the reference levels of International organizations such as the American College of radiology and the International Atomic Energy Authority. The mean entrance skin dose for the skull (AP), skull (PA), skull (LAT), cervical spine (PA), cervical spine (LAT), lumbar spine (AP), lumbar spine (LAT), pelvis (AP), and pelvis (LAT) of adult X-ray examinations was within the diagnostic reference dose level values obtained by ACR (2018) except for the ESD for chest (AP) which was 0.88 mGy. Conclusions: The results of the study concluded that by adjusting the applied tube voltage, kV, and tube current product time, mAs decreased the radiation dose to the chest X-ray by 58%.

关键词： radiology Entrance Skin Dose Chest X-Ray Dose Minimization

A Complex Interrelationship between Rectal Temperature and Dairy Cows’ Performance under Heat Stress Conditions

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Open Journal of Animal Sciences 2016年第1期6卷 24-30页

作者： Meriem Rejeb Raoudha Sadraoui taha Najar Moncef Ben M’rad National Agronomic Institute in Tunis Animal Production Department University of Carthage Tunis Tunis Tunisia

Upper limit of thermal stability and subsequent rise of thermoregulatory functions are affected by body temperature. This study was designed to determine the effects of rectal temperature (RT) on dairy cows’ performance (heart rates (HR), respiratory rates (RR), milk yield (MY), dry matter intake (DMI), digestibility, plasma concentration of vitamin C under hot climate. This study was carried out in 2009, in north-west of Tunisia using 30 Holstein cows in mid lactation. The experiment was performed in spring (15th of February-15th of March: P1) and summer (1st-30th of August: P2). On each test day, temperature-humidity index (THI), RT, HR, RR, MY, DMI, digestibility and plasma VC concentration were determined. All this parameters were affected (P 2 and r (correlation coefficient) of the regressions. R2 in regressions on RT (R2 (RT, DMI) = 0.92 (P 2 (RT, MY) = 0.91 (P 2 in regressions on THI (R2 (THI, DMI) = 0.76 (P 2 (THI, MY) = 0.63 (P 2 in regressions on RT confirms that rectal temperature constitutes a larger component of total variance of responses in dairy cows to hot environmental temperature.

关键词： Heat Stress Rectal Temperature Dairy Cows Temperature-Humidity Index

Hormonal （Thyroxin, Cortisol） and Immunological （Leucocytes） Responses to Cistern Size and Heat Stress in Tunisia

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Journal of Life Sciences 2011年第5期5卷 332-338页

作者： Rim Ben Younes Moez Ayadi taha Najar Margherita Caccamo Iris Schadt Moncef Ben M＇rad Ressources Animales Halieutiques et Technologie Alimentaire Institut National Agronomique de Tunisie Tunis 1082 Tunisie Production Animale Institut Supdrieur de Biologie Appliquee de Medenine Medenine 4100 Tunisie CoRFiLaC Regione Siciliana Ragusa 97100 Italy

This study was designed to determine the effects of heat stress on plasma leucocytes, Thyroxin (T4) and cortisol concentrations in dairy cows with small and large cistern under hot climate. This experiment was carried out in 2006, in North Tunisia, using a randomized block design per udder cistern size, using 60 Holstein cows. Cows were classified according to udder cistern size by ultrasonography as large-cisterned (44 ± 13 cm2; LC) and small-cisterned (21 ± 8 cm2; SC). The experiment was carried out in two different periods: spring (Apr. 5 (D1)) and summer (July 19 (D2), Aug. 19 (D3) and Sept. 19 (D4)). On each test day, temperature and relative humidity data were registered hourly and cows’ blood was sampled from the jugular vein to determine serum concentrates of cortisol and T4. Leucocytes (lymphocytes, eosinophils, neutrophils and monocytes) were counted differentially, and percentages of lymphocytes relative to total counted cells were calculated. Mean temperature-humidity index (THI) values were 62 ± 2, 79 ± 2, 84 ± 2, and 77 ± 1 in D1, D2, D3, and D4, respectively. Lymphocyte incidence relative to total cell counts and T4 concentrations were affected by test day (P < 0.001). Lymphocytes (%) were significantly less in hotter months. During summer, T4 concentration at D2 (87.4 nmol/L) was higher relative to concentrations at D3 (42.8 nmol/L) and D4 (53.5 nmol/L). T4 concentrations were higher (P < 0.01) in SC cows (67.7 ± 0.1 nmol/L) compared to LC cows (52.7 ± 0.1 nmol/L). Cortisol concentration was effected neither by test day nor by cistern size. However, the decrease of lymphocyte concentration during summer compared to spring could be considered as an evidence of the suppression of cows’ immune system under heat stress.

关键词：甲状腺素免疫系统皮质醇热应激白细胞突尼斯水箱荷斯坦奶牛