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Rokia M. Abdallah 한국생약학회 2006 Natural Product Sciences Vol.12 No.1
quantification of pholcodine and ephedrine hydrochloride together with either carbinoxamine maleate orterfenadine in antitussive-antihistaminic oral pharmaceutical formulations. Separations were carried out on X-Terra and symetry shield C18 column (250× 4.6 mm, 5m). The used isocratic elution systems were either0.02 M KH2PO4hydroxide, for syrup (method A), or 0.02 octanesulphonic acid sodium salt solution-acetonitrile-acetic acid in theratio of 75 : 25 : 0.5 for suspension (method B). The elution of both mixtures was achieved with a flow rate of 1ml/min. Detection was carried out by UV absorbance at wavelengths of 220 and 250 nm for syrup and suspension,respectively. The quantification of the components in synthetic mixtures and actual syrup and suspension werestandards (IS), respectively. The methods, for both mixtures, were validated and met all the requirements for thequality control analysis recommended by FDA and ICH.Keywords- pholcodine, ephedrine HCl, carbinoxamine maleate, terfenadine, HPLC
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A Data Mining Approach for Selecting Bitmap Join Indices
Ladjel Bellatreche,Rokia Missaoui,Hamid Necir,Habiba Drias 한국정보과학회 2007 Journal of Computing Science and Engineering Vol.1 No.2
Index selection is one of the most important decisions to take in the physical design of relational data warehouses. Indices reduce significantly the cost of processing complex OLAP queries, but require storage cost and induce maintenance overhead. Two main types of indices are available: mono-attribute indices (e.g., B-tree, bitmap, hash, etc.) and multi-attribute indices (join indices, bitmap join indices). To optimize star join queries characterized by joins between a large fact table and multiple dimension tables and selections on dimension tables, bitmap join indices are well adapted. They require less storage cost due to their binary representation. However, selecting these indices is a difficult task due to the exponential number of candidate attributes to be indexed. Most of approaches for index selection follow two main steps: (1) pruning the search space (i.e., reducing the number of candidate attributes) and (2) selecting indices using the pruned search space. In this paper, we first propose a data mining driven approach to prune the search space of bitmap join index selection problem. As opposed to an existing our technique that only uses frequency of attributes in queries as a pruning metric, our technique uses not only frequencies, but also other parameters such as the size of dimension tables involved in the indexing process, size of each dimension tuple, and page size on disk. We then define a greedy algorithm to select bitmap join indices that minimize processing cost and verify storage constraint. Finally, in order to evaluate the efficiency of our approach, we compare it with some existing techniques.
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A Data Mining Approach for Selecting Bitmap Join Indices
Bellatreche, Ladjel,Missaoui, Rokia,Necir, Hamid,Drias, Habiba Korean Institute of Information Scientists and Eng 2007 Journal of Computing Science and Engineering Vol.1 No.2
Index selection is one of the most important decisions to take in the physical design of relational data warehouses. Indices reduce significantly the cost of processing complex OLAP queries, but require storage cost and induce maintenance overhead. Two main types of indices are available: mono-attribute indices (e.g., B-tree, bitmap, hash, etc.) and multi-attribute indices (join indices, bitmap join indices). To optimize star join queries characterized by joins between a large fact table and multiple dimension tables and selections on dimension tables, bitmap join indices are well adapted. They require less storage cost due to their binary representation. However, selecting these indices is a difficult task due to the exponential number of candidate attributes to be indexed. Most of approaches for index selection follow two main steps: (1) pruning the search space (i.e., reducing the number of candidate attributes) and (2) selecting indices using the pruned search space. In this paper, we first propose a data mining driven approach to prune the search space of bitmap join index selection problem. As opposed to an existing our technique that only uses frequency of attributes in queries as a pruning metric, our technique uses not only frequencies, but also other parameters such as the size of dimension tables involved in the indexing process, size of each dimension tuple, and page size on disk. We then define a greedy algorithm to select bitmap join indices that minimize processing cost and verify storage constraint. Finally, in order to evaluate the efficiency of our approach, we compare it with some existing techniques.
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Phytochemical and Biological Investigation of Spergularia marina (L.) Griseb. Growing in Egypt
Omnia Gamal El-Dien,Eman Shawky,Amal H. Aly,Rokia M. Abdallah,Nabil A. Abdel-Salam 한국생약학회 2014 Natural Product Sciences Vol.20 No.3
A phytochemical investigation of Spergularia marina (L.) Griseb. growing in Egypt, has been carried out, which resulted in the isolation of seven compounds from the different extracts of the plant namely; b-sitosterol glucoside, tricin (1) dihydroferulic acid (2), vanillic acid (3), 4-hydroxybenzoic acid (4), uracil (5) and 8-hydroxy cuminoic acid (6) Structure elucidation of the isolated compounds was carried out using different spectroscopic techniques. This is the first report for the isolation of these compounds from genus Spergularia. Furthermore, 8-Hydroxy cuminoic acid and uracil were isolated for the first time from family Caryophyllaceae. The chemical composition of the volatile components present in the petroleum ether extract of Spergularia marina (L.) Griseb. using combined gas chromatography-mass spectrometry (GC-MS) is reported here for the first time. Of the 97 components present, 59 were identified including three sulfur containing compounds which represented about 1.8% of the volatiles of the total petroleum ether extract. This prompted us to study and report its possible antimicrobial activity. In addition, the antibacterial and antifungal screening of different extracts of Spergularia marina (L.) Griseb. as well as some isolates have been performed using agar diffusion method.
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Constituents of Egyptian Astragalus tribuloides Del.
El-Sebakhy, Nadia A.,Asaad, Aya M.,Abdallah, Rokia M.,Toaima, Soad M.,Verotta, Luisella,Orsini, Fulvia The Korean Society of Pharmacognosy 2000 Natural Product Sciences Vol.6 No.1
Two soyasaponins were isolated from the aerial parts of Astragalus tribuloides Del. Their structures were established on the basis of spectroscopic and chemical methods. In addition, ursolic acid, ${\beta}-sitosterol\;{\beta}-D-glucoside$ and isorhamnetin 3-O-glucoside were isolated and identified by comparing their mp, spectral and chromatographic data with those of authentic samples. This is the first report of screening and isolation of the chemical constituents of this species of genus Astragalus.
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