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971.
Effect of household processing and unit-to-unit variability of pyrifenox, pyridaben, and tralomethrin residues in tomatoes 总被引:3,自引:0,他引:3
Boulaid M Aguilera A Camacho F Soussi M Valverde A 《Journal of agricultural and food chemistry》2005,53(10):4054-4058
Residue levels of pyrifenox, pyridaben, and tralomethrin were determined in unprocessed and processed tomatoes, grown in a experimental greenhouse, to evaluate the effect of three different household processes (washing, peeling, and cooking) and the "unit to unit" variability of these pesticides in tomatoes. The study was carried out on 11 greenhouse tomato samples collected during a 5 week period in which two successive treatments with the studied pesticides were applied. Residue levels in unprocessed and processed tomato samples were determined by means of ethyl acetate extraction and gas chromatography-electron capture detection determination. The washing processing factor results were 0.9 +/- 0.3 for pyridaben, 1.1 +/- 0.3 for pyrifenox, and 1.2 +/- 0.5 for tralomethrin, whereas the peeling processing factors were 0.3 +/- 0.2 for pyridaben and 0.0 +/- 0.0 for both pyrifenox and tralomethrin. The average loss of water in the tomato pure samples during the cooking process was approximately 50%; the cooking processing factors were 2.1 +/- 0.8 for pyridaben, 3.0 +/- 1.1 for pyrifenox, and 1.9 +/- 0.8 for tralomethrin. The unit-to-unit variability factors were determined on three different greenhouse samples analyzing 10 different units of unprocessed tomatoes from each sample. In all cases, the unit-to-unit variability factor results were within the range of 1.3-2.2. 相似文献
972.
Mohamed K. M. Abdel Maksoud Fatma M. Halfaya HebatAllah H. Mahmoud Azza A. H. Ibrahim 《Anatomia, histologia, embryologia》2021,50(6):974-984
The brain is the most essential part of the central nervous system which regulates and coordinates all body activities. Based on its phylogenetic development from the neural tube, the brain is divided into rhombencephalon (hindbrain), mesencephalon (midbrain) and prosencephalon (forebrain). The present study is achieved to describe the morphological characteristics of the normal forebrain in the donkey using the matched magnetic resonance imaging (MRI) and cross-sectional anatomy. Ten cadaveric heads of healthy adult donkeys of both sexes were used. Two heads were examined using a 1.5 Tesla MRI scanner, and the brains of the other heads were gently extracted; six brains were sectioned into transverse, dorsal and sagittal slices, and two brains were grossly inspected. MR images were selected in correlation to their closely corresponding gross sections. Both cross-sectional anatomy and MRI scans showed extensive gyration of the neocortex. The forebrain structures appeared with variable intensities on three sequences, Flair, T1-weighted and T2-weighted MRI, enabling comprehensive evaluation of the relevant neuroanatomical structures. The present study provided a precise neuroanatomical atlas of the forebrain in the donkey which could help in the quick and efficient interpretation of clinical diseases of the forebrain, localization of the forebrain functions and evolutionary neurobiology. 相似文献
973.
About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered. 相似文献
974.
Weirs in the irrigation system of The Fayoum Governorate in Egypt have been modified: crests have been widened and pipes have been installed. As a result, the head-discharge ratings became invalid or unknown, and the irrigation system became difficult to manage. To obtain valid rating curves for the modified weirs, a flow-measurement programme with current-meters was started. The reasons why this programme did not yield ratings of sufficient accuracy are given.Hydraulic theory on flow over weirs and through pipes was subsequently used to arrive at acceptable ratings. An example is given for a widened weir with a pipe through its still. The theoretical rating is compared with the current-meter measurements. It is shown that the theory gives better ratings in a shorter time.Abbreviations FWSBM
Fayoum Water and Salt Balance Model Project
- FID
Fayoum Irrigation Department
- fe
feddan; 1 fe=0.42 ha 相似文献
975.
Ahmed Mohamed Fouad HebatAllah Kasem El-Senousey Dong Ruan Shuang Wang Weiguang Xia Chuntian Zheng 《Journal of animal physiology and animal nutrition》2021,105(6):1146-1153
Many studies have shown that productivity, immune system, antioxidant status, and meat and egg quality can be optimized by dietary supplementation with amino acids that are not usually added to poultry diets. Understanding the effects of these amino acids may encourage feed manufacturers and poultry producers to include them as additives. One of these amino acids is tryptophan (Trp). The importance of Trp is directly related to its role in protein anabolism and indirectly related to its metabolites such as serotonin and melatonin. Thus, Trp could affect the secretion of hormones, development of immune organs, meat and egg production, and meat and egg quality in poultry raised under controlled or stressed conditions. Therefore, this review discusses the main roles of Trp in poultry production and its mode (s) of action in order to help poultry producers decide whether they need to add Trp to poultry diets. Further areas of research are also identified to address information gaps. 相似文献
976.
Azalea-Hani Othman Yong Meng Goh Noordin Mohamed Mustapha Razlina Raghazli Ubedullah Kaka Jurhamid Columbres Imlan Ahmed Abubakar Abubakar Rasedee Abdullah 《Animal Science Journal》2021,92(1):e13610
This preliminary trial investigated the effect of transportation and lairage periods on physiological parameters of goats subjected to slaughter. Nine male Boer cross goats aged 8–12 months were transported for 6 h and kept at lairage for 3, 6, or 16 h (n = 3). Blood samples were collected at pre- (pre-T) and post-transportation (post-T), and post-slaughter (post-S) for determination of hematological parameters, serum enzyme, protein, and cortisol concentrations. Electroencephalogram readings were taken at pre-T, post-T, pre-slaughter (pre-S), and post-S to determine the median frequency (F50) and total power (Ptot) values. At post-T, there were manifestations of stress leukogram; increase in hematocrit, total protein, and muscle enzyme concentrations; and decrease in Ptot (p < 0.05). The high pre-T cortisol concentration suggests that the goats were already under stress before transportation. Stress leukogram became less evident after lairage, indicating that the goats had recovered from the stress of transportation. Although the Ptot increased at post-S especially following 3 h of lairage, F50 values at post-S did not differ from pre-L, suggesting that the pre-slaughter stress may have affected the pain threshold. It is suggested that after 6 h of transportation, goats should ideally be placed in lairage for a minimum period of 3 h before slaughter. 相似文献
977.
A. El Androusse A. El Aissami M. Rahouti H. Lahlou A. Bouloud F. Seigle Murandi 《EPPO Bulletin》2005,35(2):261-264
Pythium diclinum was isolated from a reservoir near the city of Rabat (Morocco). This is the first report of its presence in this country. Taxonomic and morphological details of the fungus are presented. The isolate grew on potato carrot agar (PCA) containing various concentrations of NaCl, up to 700 m m . Pathogenicity of the Moroccan isolate was demonstrated in vitro on lucerne seeds and seedlings. 相似文献
978.
Abdel-Rahman A. El Gamal Kenneth B. Davis Jill A. Jenkins E. Les Torrans 《Journal of the World Aquaculture Society》1999,30(2):269-275
Abstract.— Induction of triploidy and tetraploidy in Nile tilapia, Oreochromis niloticus , was investigated by heat shock, cold shock, hydrostatic pressure, and/or chemicals (cytochalasin A, B, and D). Additionally, efficacy of combined protocols was determined. Heat shock 10 min after fertilization induced triploidy when incubation temperature was 24 C but not when incubation temperature was 31 C. Heat shock of 40–41 C at 4–6 min after fertilization was effective in inducing up to 100% triploidy with hatchability similar to controls. Cold shock at 13 C for 45 min five min after fertilization induced 85–100% triploids. Heat shock and multiple heat shocking were the most effective treatments for the induction of tetraploidy. Two heat treatments of 41 C applied at 65 and 80 min after fertilization for 5 min each produced approximately 80% tetraploidy in hatched fry. Immersion of fertilized eggs in cytochalasin A, B, or D at concentrations up to 10 μg/L applied at various times and durations was ineffective in inducing triploidy or tetraploidy. 相似文献
979.
Kachani Malika Ouhelli Hammou Bouslikhane Mohamed El Hasnaoui Mohamed El Guennouni Rabia Spooner Roger 《Tropical animal health and production》1997,29(4):54S-55S
Tropical Animal Health and Production - Theileria annulata infection (tropical theileriosis) is a disease of serious economic importance in Morocco. Epidemiological and vaccination studies have... 相似文献
980.
Abstract. The effect of grazing pressure on infiltration, runoff, and soil loss was studied on a natural pasture during the rainy season of 1995 in the Ethiopian highlands. The study was conducted at two sites with 0–4% and 4–8% slopes at the International Livestock Research Institute (ILRI) Debre Zeit research station, 50 km south of Addis Ababa. The grazing regimes were: light grazing stocked at 0.6 animal-unit-months (AUM)/ha; moderate grazing stocked at 1.8 AUM/ha; heavy grazing stocked at 3.0 AUM/ha; very heavy grazing stocked at 4.2 AUM/ha; very heavy grazing on ploughed soil stocked at 4.2 AUM/ha; and a control with no grazing. Heavy to very heavy grazing pressure significantly reduced biomass amounts, ground vegetative cover, increased surface runoff and soil loss, and reduced infiltrability of the soil. Reduction in infiltration rates was greater on soils which had been ploughed and exposed to very heavy trampling. It was observed that, for the same % vegetative cover, more soil loss occurred from plots on steep than gentle slopes, and that gentle slopes could withstand more grazing pressure without seriously affecting the ground biomass regeneration compared to steeper slopes. Thus, there is a need for developing 'slope-specific' grazing management schedules particularly in the highland ecozones rather than making blanket recommendations for all slopes. More research is needed to quantify annual biophysical changes in order to assess cumulative long-term effects of grazing and trampling on vegetation, soil, and hydrology of grazing lands. Modelling such effects is essential for land use planning in this fragile highland environment. 相似文献