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211.

Objective

Scandix pecten-veneris L. is a less studied wild edible herb and is considered an extinct plant species in many parts of the world. This study was designed to evaluate its phytochemical composition and biological potential of S. pecten-veneris L.

Methods

Phytochemicals including alkaloids, flavonoids, polyphenols, and tannins were determined in extracts of S. pecten-veneris. Antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), while reducing power was tested by ferric reducing/antioxidant power (FRAP) assay. Antimicrobial activity against seven bacterial and four fungal strains was evaluated using agar well diffusion assay. Enzymes inhibition study was performed for urease, phosphodiesterase-I, and catalase-II.

Results

S. pecten-veneris showed moderate antiradical activity and reducing potential of hydroxyl radicals to about 20% of the initial value. The antioxidant activity of various extracts of S. pecten-veneris showed a linear correlation with total phenolic contents in the order of water>n-butanol>chloroform>ethyl acetate>methanol extracts. S. pecten-veneris leaves showed the highest inhibitory activity against Staphylococcus aureus while the highest antifungal activity was observed against Candida albicans. The plant extract was most potent against urease enzymes but showed moderate activity against phosphodiestrase-I and carbonic anhydrase-II.

Conclusions

Our data demonstrate that in addition to its culinary uses, S. pecten-veneris has good medicinal potential and hence could be used for treating some specific health ailments.
  相似文献   
212.
This investigation evaluated whether the mirror image could be confirmed and extended to include an ally and an enemy's ally. At the time of the 1973 Arab-Israeli War, 50 Arab students (chiefly from the confrontation states) who were attending Pakistani universities completed five semantic differental scales (brave-coward, honest-deceitful, kind-cruel, peaceful-agressive and dependable-unreliable) on two matricss: (1) Self-image and Enemy-image, (2) Ally-image and Enemy's Ally-image. Fifty Israeli students at Hebrew University also completed the scales. Thus, both groups rated Americans, Arabs, Israelis and Russians for the appropriate categories. Results confirm the mirror image from both Arabs and Israelis and its extension to Ally-image and Enemy's Ally-image. The data are somewhat clearer for the Arabs. Ratings for Israelis' Ally (Americans) are about as high as Self. The discussion offers possible explanations of the results.  相似文献   
213.
A context-based integrative framework for e-government initiatives   总被引:2,自引:2,他引:0  
The recent advances in the Internet technology have propelled the development of related applications in electronic communications and transactions, including electronic commerce and electronic government (e-government). There has been a proliferation of e-government initiatives worldwide undertaken under different forms of government, socioeconomic settings, and technological conditions. Nonetheless, the relationship between an e-government initiative and its context has not received adequate attention in the e-government literature. This paper provides an organizing framework that maps the core values (goals) of e-government to two fundamental factors; namely, the degree of e-government readiness and the level of democratization. The framework addresses the importance of the relationship between the context within which e-government initiatives are undertaken and the goals of those initiatives. From a conceptual perspective, this framework underscores the pivotal importance of the context of an e-government initiative in influencing the goals of this initiative. From a practical viewpoint, the framework provides a roadmap for policy makers to formulate policy goals of e-government initiatives commensurate with their respective environments.  相似文献   
214.
This study aimed to assess the inhibitory activities of methanol extracts from the microalgae Ankistrodesmus convolutus, Synechococcus elongatus, and Spirulina platensis against Epstein-Barr virus (EBV) in three Burkitt's lymphoma (BL) cell lines, namely Akata, B95-8, and P3HR-1. The antiviral activity was assessed by quantifying the cell-free EBV DNA using real-time polymerase chain reaction (PCR) technique. The methanol extracts from Ankistrodesmus convolutus and Synechococcus elongatus displayed low cytotoxicity and potent effect in reducing cell-free EBV DNA (EC(50)<0.01 μg/ml) with a high therapeutic index (>28000). After fractionation by column chromatography, the fraction from Synechococcus elongatus (SEF1) reduced the cell-free EBV DNA most effectively (EC(50)=2.9 μg/ml, therapeutic index>69). Upon further fractionation by high performance liquid chromatography (HPLC), the sub-fraction SEF1'a was most active in reducing the cell-free EBV DNA (EC(50)=1.38 μg/ml, therapeutic index>14.5). This study suggests that microalgae could be a potential source of antiviral compounds that can be used against EBV.  相似文献   
215.
Through ethnographic observation and content analysis, this study aims to classify the Al-Jazeera Mubasher (AJM) newsroom according to the Schantin model of newsrooms, describe the network’s convergence level based on the Dailey, Demo, and Spillman Dynamic Scale Model, and present a unique model elucidating how, specifically, convergence works at AJM. Based on the Schantin model of newsrooms, AJM can be classified as a second-generation newsroom, a “cross-media platforms newsroom.” Convergence among the different platforms of AJM is considerable, but still below full convergence level. Accordingly, the AJM newsroom can be classified into the fourth level of the Dailey et al. Dynamic Scale Model — “content sharing.” The unique AJM-specific model presented near the end of this paper depicts the ways in which different AJM platforms function and interact inside the newsroom, explains the degree of convergence between platforms, and classifies the newsroom in terms of its convergence level.  相似文献   
216.
This paper reviews data mining applications of students’ databases in educational institutions. Data mining techniques that predict and improve students’ retention rates and success is presented. Moreover, the Missions Administration at the Ministry of Higher Education in Egypt and previous analysis done on the missions databases is described. The focus of the paper is to examine how data mining can help in classifying the delayed and succeeded missioners to support the implementation of a missioners model. An investigation of how data mining can help in best or worse destinations for missioners is implemented using the Cross Industry Standard Process for Data Mining (CRISP-DM). The paper further describes the methodology used for analyzing the database for the ministry of higher education in Egypt. The process starts by extracting a subset of data including the missioners and the mission’s data, countries, specialties, departure and arrival dates and finally the extension requests from the missioners. These data were extracted into a data warehouse for the analysis purpose. The used model discovered the best and the worst countries for student mission. A detailed analysis discovered the best and the worst specialties in the previously discovered countries. Moreover, the analysis revealed the effect of the marital status on the mission of students in foreign countries. A visual display using a chart was used to express the information to business users. This model may help in supporting decision making regarding the reallocation of Egypt students to other countries.  相似文献   
217.
Reading and Writing - Phonological awareness is critical for early reading acquisition across alphabetic as well as non-alphabetic languages. The grain size of phonological awareness varies with...  相似文献   
218.
Literacy education through the LIFE Initiative and follow-up of CONFINTEA VI in the Maghreb ?C Illiteracy is seriously compromising the economic and social development of the Maghreb countries. In Morocco and Mauritania, for instance, national strategies and literacy programmes have been implemented. These efforts ought to be assessed so that lessons can be learned from them and the contribution of the national and international initiatives implemented in recent years can be evaluated. The Sixth International Conference on Adult Education provided an opportunity to launch a Maghreb-wide literacy cooperation process. Drawing on the experience of two high-priority countries (Morocco and Mauritania), the countries of the Maghreb created a mechanism for ongoing exchange within the framework of the Forum on Literacy for the Maghreb Region. The second meeting of this Forum, which was held in May 2010 in Nouakchott, was devoted to monitoring the implementation of the Belém Framework for Action and resulted in the creation of a joint cooperation programme in this domain.  相似文献   
219.
Educational institutions in the Arab Gulf are requiring rapid changes to enhance English language learning to keep up with globalization and economic growth. This urges the need for investigating policy changes such as effectiveness in curriculum orientations and their impact on the actual process of teaching in order to gauge how educational institutions are performing. This paper reports the findings of a survey study on curriculum enactment in the English Language Foundation Program of a higher education institution in the Arab Gulf region. Data collection methods included a survey and interview with teachers investigating their opinions about the curriculum, how much support it offers teachers to reach the objectives of the course, and whether/to what extent as well as the reasons why they feel they need to modify the curriculum at the implementation level. Results showed that most teachers exercised discretion in using the prescribed curriculum materials due to individual contextual factors. Results also indicated that either when implementing the prescribed or modified materials, most participants highlighted the importance of using reliable quality resource materials that can help teachers as well as students to enhance the learning process. Findings have implications for English as a second language curriculum design in Arab higher educational contexts.  相似文献   
220.
The main aim of the study was to evaluate trainee teachers working commitment in their teaching practicum. There were seven component teaching practices and eleven demographic factors. The instrument of the study was extracted from various sources to suit the research design based on Units, Treatments, Observing, and Surveying (UTOS) model modification. The reliability index obtained for both research instruments were reasonably good ranging from 0.7030 to 0.9053. A total of 276 trainee teachers who were doing their practical teaching in one of the state in Malaysia (Kelantan). Stratified random sampling was used. They made their self-assessment by using the working commitment instrument. At the same time, their teaching processes were guided through conferences, observations and finally evaluations to get their comparative scores of teaching performance. The data were analyzed by using statistical multiple regression at significant ofp 〈 0.05. As a result, a linear equation of trainee teachers' commitment comprises contribution of work load, work satisfaction, study opportunities, teachers' prospect, marital status, teaching practices, planning and preparation teaching procedure, and religious studies. Furthermore the findings of this study led to some suggestions for future teachers development and become more efficient and adaptive.  相似文献   
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