96 research outputs found
The Degree of Use of Alternative Assessment Strategies by Home Economics Teachers and the Relationship with their Female Students’ Self- efficacy in Najran Region
The present study aimed to investigate the use of alternative assessment strategies by home economics teachers, the various difference of alternative assessment strategies according to the training courses and teaching experiences, and the relationship between the use of alternative Assessment strategies by home economics teachers and their female students’ self- efficacy. The study sample consisted of (90) home economics teachers at Najran intermediate schools, and a random sample of (180) female students. The findings showed that the use of alternative assessment strategies by home economics teachers was very high for some items of the questionnaire such as pencil and paper strategy, worksheets, monthly tests, work groups, questions and answers, portfolios, and projects. The findings also showed that there are statistically significant differences at the level of (0.01) regarding training courses in home economics teachers’ responses to the questionnaire of alternative assessment strategies. In addition, there are statistically significant differences at the level of (0.01) according to the years of experience in home economics teachers’ responses to the questionnaire of alternative assessment strategies. However, there is no statistically significant interaction among the two study variables: training courses (yes and no), years of experience (1-5 years, 6-10 years, 11 years and more) and the interaction between them in home economics teachers’ responses to the alternative assessment strategies. Moreover, the findings concluded to the existence of a positive correlation and statistically significance at the level of (0.01) between the use of alternative assessment strategies by home economics teachers and their relationship with female students’ self- efficacy. Key words: Alternative Assessment- Home Economics- Self- efficac
Expression of e-cadherin, n-cadherin and snail and their correlation with clinicopathological variants: an immunohistochemical study of 132 invasive ductal breast carcinomas in Egypt
OBJECTIVE: To evaluate the expression of the cell adhesion molecules E-cadherin and N-cadherin and the transcription factor Snail in invasive ductal breast carcinomas and to determine their relationships with clinicopathological features. METHODS: Immunohistochemistry was used to examine E-cadherin, N-cadherin, and Snail protein expression in 132 invasive breast carcinomas. RESULTS: The expression of E-cadherin was decreased (negative or weak) in 37.1% of invasive carcinomas, while N-cadherin and Snail overexpression were detected in 51.9% and 40.9% of carcinomas, respectively. Low E-cadherin expression was significantly correlated with poorly differentiated carcinoma (53.1%), positive node status (80.9%), poor Nottingham Prognostic Index (64.7%), and the presence of estrogen and progesterone receptors. Overexpression of N-cadherin and Snail were also significantly correlated with poorly differentiated carcinoma, positive node status, and poor Nottingham Prognostic Index but were correlated with the absence of hormone receptors. Loss of E-cadherin immunoexpression was strongly associated with the presence of membranous N-cadherin (87.8%) and nuclear Snail (69.4%). CONCLUSION: Loss of E-cadherin and overexpression of N-cadherin and Snail in breast carcinomas may play a central role in the development of invasive ductal breast carcinoma. These biomarkers may provide a valuable reference for the study of invasive ductal carcinoma progression and to characterize the biological behavior of the tumor. In the future, increased N-cadherin and decreased E-cadherin expression may be used as indicators of the progression and prognosis of invasive ductal carcinoma
Cogeneration of electricity and cooling by gas turbines
Bu çalışmanın amacı atık gazların soğutma elde etmek için kullanıldığı gaz türbinli bileşik ısı-güç (kojenerasyon) sistemlerinin termoekonomik çözümlemesidir. Termoekonomik çözümleme, termodinamik çözümlemenin yanında bu tür sistemlerin ekonomik olurluluğunu ve ürünlerin maliyetlerini irdeler. Bu çalışmanın, sıcak iklim kuşağında yer alan ülkelerde elektrik üretiminin bir yan ürünü olarak soğutma elde edilmesini özendirmesi umulmaktadır. Böylece birincil enerji tasarruf edilebilecektir. Bileşik ısı-güç üretimi elektrik ve ısının aynı santralden elde edilmesi anlamına gelmektedir. Bileşik ısı-güç üretimi temelde, elektrik üretiminde kullanılan gaz türbini, buhar türbini ve gaz motorları gibi ısı makinalarının atık ısısından yararlanmayı amaçlar. Böylece yakıt enerjisi daha etkin kullanılmış olur. Bunun iki önemli sonucu vardır. İlk olarak giderek tükenen fosil yakıtlardan tasarruf etmek, ikinci olarak küresel ısınma kaygısını, atmosfere daha az karbon dioksit atarak azaltmak. Bu çalışmada gaz türbini, atık ısı kazanı, buhar türbini ve absorbsiyonlu soğutucudan oluşan bir bileşik ısı-güç sisteminin sayısal modeli oluşturulmuştur. Modelin hesaplamalarını yapmak için Fortran dilinde iki program yazılmıştır. Birinci program sistemin birinci yasa çözümlemesini yapmakta, yakıt ve hava debilerini hesaplamakta, sistemin her noktasında sıcaklık, basınç ve ekserji debilerini bulmaktadır. İkinci program sistemin her noktası için maliyet akılarını ve birim ekserji maliyetlerini hesaplamaktadır. Önerilen sistem konvansiyonel sistemlerle karşılaştırıldığında, soğutma ve elektrik üretimi için hesaplanan maliyetlerin daha düşük olduğu görülmüştür. Ayrıca konvansiyonel yöntemlerle elektrik ve soğutma eldesinde enerjiden yararlanma oranı % 50 dolaylarında kalırken, incelenen sistemde enerjiden yararlanma oranı % 70’leri bulmaktadır. İncelenen sistem için geri ödeme süresi 7 ile 9 yıl arasında değişmektedir. Anahtar Kelimeler: Trijenerasyon, kojenerasyon, absorpsiyonlu soğutma.The objective of this study is the thermoeconomic analysis of the gas turbine cogeneration systems where the exhaust gases are used for refrigeration purposes. The thermoeconomic analysis involves thermodynamic considerations as well as the calculation of economic feasibility of such systems and cost rates of the products. Cogeneration is defined as simultaneous production of power and heat. In essence it aims to utilize the exhaust heat of prime movers such as gas turbines, steam turbines and gas motors for producing electricity. Thus a more effective utilization of fuel is achieved. This has two important consequences. First of all use of lesser amounts of fuel in the context of decreasing fossil fuel supplies and secondly reduced carbon dioxide emissions in view of the global warming concerns. The fact that the exhaust heat may be used in absorption chillers introduces a new direction for cogeneration. Thus besides electricity and process heat, cooling effect may be produced by cogeneration. This application is sometimes called trigeneration in the literature. Cogeneration was used in Europe and especially in former eastern block countries mainly in conjunction with district heating. But it has also gained wide usage in industry around the world in the last 20 years. There are many applications of cogeneration in industrial plants where electricity and process heat are produced simultaneously. There are two types of absorption refrigeration cycles that are widely used in practice. These are the aqua?ammonia cycle and the lithium bromide?water cycle. The former can be used for refrigeration at temperatures below 0°C. The latter is generally used in air conditioning systems and the minimum temperature is limited to approximately 4°C. The thermodynamic calculations related to these cycles are explained with the help of two numerical examples. The coefficient of performance (COP) of the aqua-ammonia system considered in the first example was calculated as 0.5. The COP of the Lithium-bromide-water system was 0.78. The COP depends on the evaporator, condenser pressures and the generator temperature. The average COP of the absorption refrigeration systems in this study was taken as 0.6. A numerical model of a cogeneration system consisting of a gas turbine system, heat recovery steam generator, a steam turbine, a pump and an absorption refrigeration unit was formed in this study. The steam turbine and the absorption refrigeration unit are coupled to the gas turbine system through the heat recovery steam generator. The gas and steam cycles were considered as steady flow systems, air and the combustion products were assumed to be ideal gas mixtures. Natural gas (methane) was used as fuel. Two programs were written to realize the computations of the model. The first program is for the first law analysis of the system, it calculates the mass flow rates of fuel and air, temperatures, pressures and exergy rates at all state points of the system. The second program calculates the cost rates and cost per unit exergy at all state points of the system. The numerical model was simulated with different values of the decision variables. These are the pressure ratio of the compressor, cost of the natural gas, the investment cost of the gas turbine and the investment cost of the steam turbine. Exergy flow rates, cost rates and unit exergy costs were calculated for each state point of the system. Furthermore the exergy destruction, relative cost difference and exergoeconomic factor were calculated for each component of the system. Finally the payback period of the system for different parameters were calculated. When the system is compared with the conventional systems it is seen that the costs for electricity and refrigeration are lower. The fuel utilization effectiveness has been found as 70 %, as compared to 50% for the separate production of products. The payback period was between 7 and 9 years. Keywords: Trigeneration, cogeneration, absorption refrigeration
An Epistemological Introduction to the Didactics of the Case Marking System in Arabic
يهدف هذا البحث إلى أن يقدم مدخلًا إبستيمولوجيًّا مؤسسًا على قدر من الواقعية المعبرة عن القدرة اللغوية بوصفها [قدرة تواصلية بازغة عن استعداد عصبي للأدمغة البشرية]، مما يمكِّننا من محاولة تقديم موجِّهات تعليمية تتناسب وطبيعة اكتساب أدمغتنا للغة الطبيعية بصفة عامة، واكتساب إسناد العلامة الإعرابية في اللغة العربية بصفة خاصة، وهو ما ينعكس على الكفاية التفسيرية لأداء المتعلمين، وإمكان تقييم إنتاجهم على المستويين: الكمي، والكيفي.This research aims to provide an epistemological approach based on a degree of realism expressing linguistic ability as [a communicative ability emerging from a nervous readiness for human brains], which enables us to try to provide educational directives commensurate with the nature of our brains acquiring natural language in general, and acquiring the attribution of the syntactic sign in The Arabic language in particular, which is reflected in the explanatory adequacy of the learners' performance, and the possibility of assessing their production at the two levels: quantitative and qualitative. The research aimed to discuss some of the problems of assigning an infinitive sign, whose attribution is not due to the functional necessity of communication. From that, what can be attributed primarily to a pattern of unconscious cognition of the attribution of the inflection mark, and from it what can be attributed to the effect of the acoustic environment on the inflection mark, which obscures the functional use of it. In all of our effects, we should explain how the benefit of the deductive transfer from the scientific knowledge presented in the grammar lesson on the one hand, and the achievements of the computer revolution on the other hand, especially at the level of educational Corpus
The Effect of Instructional Guidelines on Pregnant Women’s Perception Regarding Urinary Tract Infection
Background: Urinary tract diseases (UTIs) are the foremost predominant diseases in pregnancy, counting for about 20% of all pregnancies. Moreover, they are responsible for 10% of all hospitalizations during pregnancy. Aim: The study aimed to evaluate effect of instructional guidelines on pregnant women’s perception regarding urinary tract infection. Design: A quasi-experimental research design was used at this study. Setting: The study was conducted in Obstetric and Gynecological clinic in El Hussein Hospital Al-azar University. Sample: A purposive sample of ninety-six pregnant women with urinary tract infection. Tools: The study utilized two assessment tools: a Structured Interviewing Questionnaire and Likert scale of women attitudes for pregnant women regarding urinary tract infection (UTI). Results: The findings of the study indicated that prior to the application of instructional guidelines, more than two-thirds of the pregnant women had an unsatisfactory level of knowledge about UTI. However, after the application of the guidelines, more than three-thirds of them demonstrated satisfactory knowledge. Similarly, nearly three-quarters of the participants held a negative attitude towards UTI before the guidelines, whereas after the guideline's application, more than three-thirds of them displayed a positive attitude. Conclusion: Based on these results, it can be concluded that the instructional guidelines effectively improved both the knowledge and attitude of the pregnant women towards UTI, thereby supporting the research hypothesis. Recommendations: The study recommends the implementation of routine screening for UTIs in all pregnant women during each trimester of pregnancy, including bacteriuria examination and urine culture, to ensure early diagnosis and appropriate treatment
Enzymatic Interesterification of Palmolein with Stearic Acid by Using Immobilized Pseudomonaslipase
Interesterification of palm olein with stearic acid by immobilized Pseudomonas lipase in n-hexane was studied. The catalytic performance of the immobilized Pseudomonas was evaluated by determining the change in fatty acid composition and concentration using gas liquid chromatography (GLC), and the change in triglyceride
composition and concentration using high performance liquid chromatography (HPLC). Interesterification resulted in the formation of trisaturated triglyceride tripalmitin (PPP) and 1,2-dipalmitoyl-stearoyl glycerol (PPS), both of which were absent in the original oil. It also resulted in a decrease in the concentrations of the four main triglycerides in palm olein namely I-palmitoyl-dioleoyl glycerol (POO), 1,3-dipalmitoyl-2-oleoyl glycerol (POP), 1-palmitoyl-2-oleoyl-linoleoyl glycerol (POL) and 1,3-dipalmitoyl-2-linoleoyl glycerol (PLP). On the other hand, interesterification increased the concentrations of 1-stearoyl-dioleoyl glycerol (SOO), 1-palmitoyl-2-oleoyl-stearoyl glycerol (POS) and 1,3-distearoyl-2-0Ieoyl glycerol (SOS). Overall, the combined concentration of polyunsaturates, triunsaturates, and diunsaturates decreased, while that of the full saturates and mono unsaturates increased, thus raising the slip melting point of the final product. Interesterification caused substantial incorporation of stearic acid into the palm
olein, with concomitant decreases in the palmitic and oleic acid contents. Immobilizing the Pseudomonas lipase resulted in a fast reaction, with the steady state reached after
about 6 hours. Adding water to the reaction mixture increased the lipase activity
THE EFFECT OF WATERING REGIMES AND BIO AND CHEMICAL TREATMENTS ON FLOWERING OF EUPHORBIA MILII VAR. LONGIFOLIA PLANTS
This study was carried out in the nursery of Ornamental Plants and Landscape Gardening Research Department, Horticulture Research Institute, Agriculture Research Centre, Giza, Egypt in two successive seasons (2015/2016 and 2016/2017) to study the effect of soil drench with some bio- and chemical materials (moringa extract, potassium silicate, salicylic acid and ascorbic acid) combined with different water intervals (1, 2, 3 and 4 weeks) on vegetative growth, flowering and chemical composition of Euphorbia milii var. longifolia transplants grown in 25 cm plastic pots. Results could be briefed in the following: watering at 2 weeks seems to be more effective in increasing the values of most studied characters. On the other hand, both moringa extract and ascorbic acid resulted in the highest values of studied characters. Regarding combination between irrigation intervals and different bio- and chemical materials, all untreated control plants irrespective of their watering regime, in addition to plants watered at 4 weeks interval and treated with either moringa extract or potassium silicate, did not flower at all over the period of this study. Meantime, the same plants recorded the lowest values of many characters irrespective of the watering regime. Plants treated with moringa extract and watered at 1 week interval had the highest values of flower diameter, number of branches, root length and root fresh weight. Those watered at 2 weeks interval achieved the highest rank of number of leaves and flowers, flower diameter, fresh and dry weight of flowers, P%, K% and total chlorophyll content. Plants treated with ascorbic acid combined with irrigation at 2 weeks interval got the highest records of plant height, stem length, leaf length, fresh weight ofleaves, stem fresh and dry weights, total chlorophyll and carotenoids content. In conclusion it is recommended to irrigate Euphorbia milii var. longifolia grown in 25 cm plastic pots at 2 weeks interval, combined with treating plants with either moringa extract or ascorbic acid in order to get the best results
DETERMINING WATER REQUIREMENTS FOR ACALYPHA WILKESIANA SHRUBS IN RELATION TO GROWING MEDIUM MIXTURE
This study was carried out in the nursery of the Ornamental Plants and Landscape Gardening Res. Dept., Hort. Res. Inst., A.R.C., Giza, Egypt during 2014/2015 and 2015/2016 seasons to find out the response of Acalypha wilkesiana grown in different potting mixtures to different irrigation regimes. Five types of equal proportions potting mixtures (v:v) i.e. sand + peat moss (Mix. 1), sand + perlite (Mix. 2), sand + vermiculite (Mix. 3), sand + peat moss + perlite (Mix. 4) and sand + peat moss + vermiculite (Mix. 5), and 4 levels of irrigation water at 25, 50, 75 and 100% of pot water capacity, and their interaction, were applied in this study. Vegetative and root parameters as well as the leaves content of total chlorophyll, carotenoids, anthocyanin and the percentages of total carbohydrate, N, P and K were recorded. The obtained results showed that there was a great influence of the different potting mixtures particularly those containing peat moss on A. wilkesiana growth e.g. Mix. 5 resulted in the highest records of plant height, number of leaves, number of branches, leaf area, stem fresh weight, root dry weight and N% in the leaves. On the other hand, irrigation at 25% pot water capacity resulted in the lowest values of almost all studied characters, while, watering at 75% pot water capacity gave rise to the highest plant height, number of leaves, number of branches, leaf area, root length, stem fresh weight, dry weight of leaves, stem and root dry weights, total carbohydrate %, anthocyanin content and percentages of N, P and K. Regarding the interaction treatments, all potting mixtures recorded the highest values in most cases when combined with irrigation regime at 100 or 75% pot water capacity. From the above results and to obtain high quality Acalypha wilkesiana shrubs with reducing the amount of irrigation water by 25%, it is recommended to use the Mix. 5 (sand + peat moss + vermiculite) + irrigation at 75% pot water capacity
Cordycepin for Health and Wellbeing: A Potent Bioactive Metabolite of an Entomopathogenic Medicinal Fungus Cordyceps with Its Nutraceutical and Therapeutic Potential
Cordyceps is a rare naturally occurring entomopathogenic fungus usually found at high altitudes on the Himalayan plateau and a well-known medicinal mushroom in traditional Chinese medicine. Cordyceps contains various bioactive components, out of which, cordycepin is considered most vital, due to its utmost therapeutic as well as nutraceutical potential. Moreover, the structure similarity of cordycepin with adenosine makes it an important bioactive component, with difference of only hydroxyl group, lacking in the 3′ position of its ribose moiety. Cordycepin is known for various nutraceutical and therapeutic potential, such as anti-diabetic, anti-hyperlipidemia, anti-fungal, anti-inflammatory, immunomodulatory, antioxidant, anti-aging, anticancer, antiviral, hepato-protective, hypo-sexuality, cardiovascular diseases, antimalarial, anti-osteoporotic, anti-arthritic, cosmeceutical etc. which makes it a most valuable medicinal mushroom for helping in maintaining good health. In this review, effort has been made to bring altogether the possible wide range of cordycepin’s nutraceutical potential along with its pharmacological actions and possible mechanism. Additionally, it also summarizes the details of cordycepin based nutraceuticals predominantly available in the market with expected global value. Moreover, this review will attract the attention of food scientists, nutritionists, pharmaceutical and food industries to improve the use of bioactive molecule cordycepin for nutraceutical purposes with commercialization to aid and promote healthy lifestyle, wellness and wellbeing
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