خيارات البحث
النتائج 31 - 40 من 71
The Hsp70 Expression Profiling in Fayoumi and Matrouh Chicken Subjected to Heat Stress النص الكامل
2021
Esraa SeifEldin | Alia Elsaudi | Khalid Fahmy | Lamiaa Radwan
The present study was undertaken to test the effect of heat stress (39 °C) for 4 hours on Hsp70 mRNA profiling in two chicken genotypes. Expression levels of hsp70 were used to assess the heat tolerance of two Egyptian local genotypes (Fayoumi and Matrouh). The expression level of the hsp70 gene is high in the Fayoumi type as opposed to the Matrouh type. In blood, after four hours of exposure, the hsp70 mRNA expression analysis revealed higher expression levels. These results showed that the acquired thermotolerance is positively linked to the stress memory. Within the two genotypes, Fayoumi type exhibited the highest means for hsp70 production, and therefore the heat stress is better tolerated, which indicates that Fayoumi mortality rate might be lower genetically under heat stress
اظهر المزيد [+] اقل [-]The Level of Farmers' Knowledge of the Negative Effects of Using Pesticides in Some Villages in Qalyubia Governorate النص الكامل
2021
Eman Abuqamar | Samia Mahrous | Yaser Hemari | Kadry Mahmoud
The study aimed to determine the level of knowledge of the surveyed farmers on the neg-ative effects of the use of chemical pesticides, and their sources of information in this field, and determine the significance of the relation-ship between the level of knowledge of the farmers with the negative effects of the use of pesticides and some independent studied vari-ables, and finally identify the problems that limit the safe use of chemical pesticides ,the data of this study were collected during July and August 2020 by means of a personal inter-view questionnaire for a regular random sam-ple of farmers in the villages of Qalyubia Gov-ernorate. It was determined using the Kreijce and Morgan equation, and its strength reached 377 farmers, The selected data were analyzed and presented using quantitative method, the arithmetic mean, Chi-square test, The most important results were the following :the level of the respondents' knowledge of the negative ef-fects of using chemical pesticides was high, with the percentage of their average knowledge scores reaching 82.9, It was found that the most important sources of information: pesticide merchants, personal experience, rel-atives, It was found that there is a significant relationship at the level of 0.01 between the level of the respondents' knowledge of the neg-ative effects of chemical pesticides and each of the following independent variables the re-spondent’s age, gender, educational status, profession, number of years of experience in farm work, social participation, Frequency of agricultural service centers, and the number of years of experience in using pesticides. It was also found that the most important problems in the research area are: the shortage of extension agents, the scarcity of extension activities, re-spectively, Based on the results of the study, six proposals were formulated in the form of recommendations to be submitted to decision-makers.
اظهر المزيد [+] اقل [-]Performance Evaluation of Solar Pump for Landscape Irrigation System النص الكامل
2021
ٌRofida Mohamed Rashid | Mahmoud Hegazy | Usama Bedair | Mohammed Hewidy
Experiments were performed at a private garden in Al-Qaddbah, Al-Gharbia Governorate, Egypt. The latitude and longitude of the experiment site are 30°56'37''N and 30°47'01'' E, respectively, and the altitude equals 30 m, at the 2019 season, the total landscape area (13.5m x 9m) was divided into 6 treatments each of an area (20.25 m2), three plots were operated using solar system while the other three plots were operated using electric system. The irrigation systems were similar, 4 multi-stream sprayers, (90◦) and the distance between the sprayers was (4.5*4.5 m), different operating times were applied on each plot, under local climatic and working conditions. All the plots were planted with turfgrass (Passpalm10). The obtained results show, at solar energy powered system, uniformity coefficient increased from (65% - 75%) at operating time (10 –30 min), then it decreased during operating time (40 - 60 min), while at electric energy powered system the averages of the uniformity coefficient were (76% - 80%), at operating time (10 –40 min), while at operating time (45 - 60 min) the uniformity coefficient decreased to (75%), due to the silt clogging in the sprayers' filters. The energy saving reached (63%) with solar energy operation rather than electric energy operation in the summer season. The least total cost was (351 L.E/m2/year) at the landscape area (A3 60.75m2), which was irrigated on 3 cycles per day to give the highest uniformity coefficient (75%). When operating the solar batteries at full charge 3 - 4 times for a plot area of (20.25 m2). The hydraulic power obtained was (17.86 –26.74 W), the sprayer radius was (5.3 –5.8 m), at an average pressure of (1.9 -2.5 bar) which gave the best uniformity coefficient. The turf quality index was higher using electric motor rather than solar motor.
اظهر المزيد [+] اقل [-]Impact of Microbial Synergism on Second Generation Production of Bioethanol from Fruit Peels Wastes النص الكامل
2021
Sameh Fahim | Kamal Mahmoud
Fruit peels annually accumulate in huge amounts, fruit wastes are rich in lignocellulo-sic component which can be recovered into mono simple carbohydrates able to utilize for bioethanol production. The enzymatic hydrol-ysis of lignocelluloses is known to be a key to the second-generation biofuel, the challenge is the still expensive enzymes involved in the saccharification process, loss of the most hem-icellulose pentose sugars which were non-fer-mentable as base, beside the presence of ham-pers lignin thus require to resolve its problem.As part of study, followed the cost-effective means for bioethanol producing from four fruit peels (Banana, Orange, Mango and Water-melon), yielding of enzymes from co-fungal cultivation carried by Aspergillus niger and Phanerochaete chrysosporium, followed by co-fermentation of the saccharified sugars us-ing yeast belong to Saccharomyces cerevisiae and Kluyveromyces marxianus which contrib-uted for bioethanol production in 8 L lab-scale reactor. The fermented sugars recovering was reached to 27.77 g.l-1 from banana peels which were found to be good exploited as potential raw source, co-fungal enzymatic hydrolysis followed by yeast co-fermentation led to sub-stantial yield by 10.74 g.l-1, the adding of calcium oxide increased the purity which leads finally to 97.5 wt % of pure bioethanol. Thrust towards fossil fuels replacement with renewa-ble clean fuels such as bioethanol by using fruit peels residuals which are considered renewa-ble energy source may also help in CO2 miti-gation.
اظهر المزيد [+] اقل [-]An Economic Analysis Study of the Structural Composition of the Labor Market in the Egyptian Agricultural Sector النص الكامل
2021
shady abdelmawgud | dirar alotaibi | Hossam Abdul Aziz
يAgricultural production is characterized by seasonality that leads to an imbalance in agri-cultural labor market. However, this is pre-sumably due to the imbalance between the sea-sonal agricultural labor demand and supply, thus, resulting seasonal unemployment. This paper aims to investigate and analyze the struc-ture of Egyptian agricultural labor market throughout the period 2000-2020 via employ-ing econometric tools. The results show that, the agricultural disguised employment does not consider permeant agricultural labor its source, but rather it is due to seasonal agricul-tural employment, due to its negative marginal productivity, in which is the main cause for disguised unemployment appearance.
اظهر المزيد [+] اقل [-]A Study on Pesticide Sprayer Powered by Solar Energy Appropriate for Small Farms النص الكامل
2021
AHMED El-Sayed | Abdel-Fadil Kabany | Waleed Elhelew
The study was conducted on a knapsacksprayer powered by a DC motor through a 12 V lead acid battery charged from a solar panel (photovoltaic) directed to sun rays. The system was installed and tested in the western desert on a small-scale farm at Frafra Oasis (New val-ley). This study aimed to evaluate and develop a knapsack sprayer powered by a solar energy for overcoming operator fatigue and shortage of traditional energy in Egypt’s western desert. The experiments were conducted during the period which starts in August 2019 till Febru-ary 2020. The main parts of the system consist of photovoltaic (PV) or solar cells, charger controller, rechargeable battery, and DC motor speed control with dimmer and pump which was attached with a tank 20 liters capacity for sucking and pressurizing the liquid to the boom of the sprayer through a flexible hose. The main results of experiments were as fol-lows: The time for recharging the battery com-pletely was found 330 minutes (5.5 hours) to charge completely from 10.55 V – 13.85 V, with current intensity 1.67 Ampere. The bat-tery discharge time was varied due to drop the battery voltage from 13.85 – 10.55 Volts. De-pending on the motor speed, which is the time for discharging the battery was found 4 – 9 hours, when motor pulled 0.85 - 1.85 Amps at 2000 - 3400 rpm and this time at deferent speed is enough to spray area 3 - 6.82 fed/day "day work = 6 hours" with application rate 67 - 104.7 l/fed. The number of droplets and the area coverage percentage ranges from 30 – 146.33 drops and 13.96 – 27.97% for one cm2 of simulator targets at a speed ranging from 2000 – 3400 rpm, respectively.
اظهر المزيد [+] اقل [-]Assessment of Some Essential Oils and Their Mixtures as Material Repellents Against Adults of The Confused Flour Beetle, Tribolium confusum (Du Val) (Coleoptera: Tenebrionidae) النص الكامل
2021
salwa pasha
Repellency of the six essential oils (EOs), Clove (Eugenia aromaticum), Aloe (Aloe vera), Lemon (Citrus limon), Camphor (Euca-lyptus camaldulensis), Mint (Mentha spicata), Marjoram (Origanum vulgare) were evaluated against adult of the confused flour beetle Tri-bolium confusum, by allowing adults to choose between untreated filter paper halves with 1 -2g white flour or treated with different concen-trations of the oils and their mixture at three different exposure times. In individual oils ex-periments, Eucalyptus camaldulensis was found to be the best effective of repellent effi-cacy, followed by Mentha spicata and Eugenia aromaticum. Citrus limon and Aloe vera have moderate repellent efficacy. Results of combi-nation effective showed that mixtures' repel-lant activity. It has been shown that the most powerful mixture of Clove + Mint repels activ-ity against adults with Lemon + Aloe, Lemon + Marjoram, Lemon + Mint, and Mint + Aloe during the entire exposure period, while Lemon + Camphor and Camphor + Mint lost repellent activity after 24 hours.
اظهر المزيد [+] اقل [-]Effect of Different Dried Methods and Storage on Some Enzymes Activity and Quality of Cactus pear and Papaya النص الكامل
2021
Marwa Abdel-Hady | magdy El-shemy | samar Mahdy | Effat rizk
This study was to evaluate the activity of peroxidase, polyphenoloxidase, pectin methyl esterase and protease as well as the proximate chemical composition and quality parameters of cactus pear and papaya which were dried by different methods and stored for 6 months. Our findings revealed that the highest moisture content was recorded in osmo – freeze drying of papaya and cactus pear. On the other hand, the browning index of oven dried papaya and cactus pear was higher than those dried with osmotic dehydration and osmo – freeze drying. The less activity of peroxidase was recorded in osmo – freeze drying of papaya and cactus pear. Also, the highest reduction of polyphe-noloxidase activity was noticed in osmo–freeze drying methods. While oven dried pa-paya recorded the highest activity of pectin methyl esterase pectin (0.34 %), complete in-activation was shown in other dried methods after 6 months of storage at 4 ±1℃. Different dried methods of papaya caused to reduce the activity of protease, moreover, complete inac-tivation was observed after 3 months from storage. The quality parameters for sensory evaluation of dried cactus pear and papaya demonstrated that osmo–freeze drying was more favorable to preserve samples followed by osmotic dehydration and oven drying.
اظهر المزيد [+] اقل [-]Biomass Production of Microalgae using Agricultural and Industrial Wastewater النص الكامل
2021
Merihan Abdel-Raouf | Sohair Nasr | Elham Aref | Khadiga Aboutaleb
Growing wastewater microalgae contrib-utes to the elimination of nutrients present in wastewater because they need N and P for the synthesis of proteins, nucleic acid, and phos-pholipids. The most sustainable approach for achieving high biomass and high lipid build-up, along with environmental protection. In the current research, nine microalgae were culti-vated on two variations of wastewater (agricul-tural and industrial dyes) and compared to the synthetic medium. The results indicated that after three weeks of the incubation period, the ability of microalgae to grow in sterilized (syn-thetic medium and wastewater) and gave greater biomass and chlorophyll (a) than in non-sterilized ones. Out of the tested nine mi-croalgae, four microalgae (Anabaena oryzae, Spirulina platensis, Anabaena sp (2) and Nos-toc sp) were selected which gave the highest significant values of dry weight, biomass productivity and chlorophyll (a) content. The selected microalgae showed the highest signif-icant values of the chemical composition, i.e., total carbohydrate, protein and lipid when cul-tivated in agricultural wastewater more than those cultivated in both industrial dye’s wastewater and synthetic broth medium. Among four microalgae, two microalgae of A. oryzae HSSASE6 (KT277789), and S. platen-sis NIES-39 (A00800) were chosen where the chemical composition contents ranged from 1.17 to 1.21-fold and 1.03 to 1.06-fold of car-bohydrate, 1.06 to 1.09-fold and 1.88 to 1.93-fold of protein and 1.41 to 1.52-fold and 1.76 to 1.90-fold of lipid more than those of other microalgae, respectively. The agriculture wastewater was inoculated with a single cul-ture of A. oryzae HSSASE6 (KT277789) or S. platensis NIES-39 (A00800) individually with 10 % of inoculum size, which more preferred than was inoculated with consortia culture. Re-sults also showed that A. oryzae HSSASE6 (KT277789) was more efficient strain for giv-ing biomass and productivity in agricultural wastewater than S. platensis NIES-39 (A00800) (about 28% more).
اظهر المزيد [+] اقل [-]Physico-Chemical Properties, Fractionation and Antioxidant Activity of Some Essential Oils Utilized in Mayonnaise Preparation and Storage النص الكامل
2021
Mamdouh El kalyoubi | Mohamed Khalaf | Abdel-Aziz Shehata | Wafaa Abozeid | Mohamed Mansour
Two types of essential oils (thyme and Stachys) were used in this Estimation. The chemical composition, antioxidant activity (by DPPH assay) and the rancimat method were used to assess the stability effect of these essential oils. The tested oils were added to mayonnaise to evaluate its capability for inhibition of secondary oxidation products. By DPPH assay, antioxidant activity showed that thyme essential oil was the best antioxidant agent as radical scavenging agents at 450 and 500 ppm concentrations, even better than BHT at the200 ppm concentration. As a typical antioxidant, butylated hydroxytoluene was used for comparison. The mayonnaise samples prepared by adding thyme, stachys essential oils and TBHQ (control +) at concentrations of 200,400, 600 and 200 ppm into the sunflower oil free from antioxidant. At the amounts used in this study, thyme and stachys oils were significantly successful in reducing the oxidation of sunflower oil, especially, at 500 ppmwhich showed more efficient than BHT. Specifically, in the presence of thyme oil, the induction period of sunflower oil was considerably elongated. However, butylated hydroxytoluene (BHT) was more efficient than thyme and Stachys oils at the 200-ppm concentration against oxidation of oils. all concentrations of thyme and stachys essential oils had an antioxidant activity similar to synthetic antioxidant of TBHQ at a concentration of 200 ppm for inhibition of secondary oxidation products in mayonnaise in comparison with the control sample. As a conveniently available source of natural antioxidants, thyme and stachys essential oils can be used for use in fats, oils and food containing fats.
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