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Chemical Constituents from Fadogia homblei De Wild (Rubiaceae)
No full textABSTRACT The total of fourteen known compounds was isolated from the fruits, leaf and stem of Fadogia homblei De Wild. (Rubiaceae) and identified as: a coumarin, 7-hydroxy-6-methoxy-2H-1-benzopyran-2-one (scopoletin) 1, two flavones; 3′,4′,5,7-tetrahydroxyflavone (luteolin) 2 and quercetin-3-O-β-D-galactoside 3, four lupane triterpenoids; lupeol 4, betulinic acid 5, 3β-dodecanoyllup-20(29)-en-28-al 6, lup-20(29)-en-3β-ylhexadecanoate 7, and two steroids; sitosterol 8, stigmasterol 9, a lignan 4,4′-dihydroxy-3,3′-dimethoxy-7,9′:7′,9-diepoxylignan ((-)-pinoresinol) 10, a phaeophytin A 11, an uracil 12, an oleanolic acid 13, and an ursolic acid 14. To our best knowledge, this is the first report for isolation of these compounds from this species. This finding is nevertheless significant as it is the first report of uracil from a plant source other than from various species of ferns
Introduction To Reduce Hot Dose Spots in Craniospinal Irradiation: An IMRT Approach with Matching Beam Divergence SCIENCE & TECHNOLOGY
No full textCraniospinal irradiation (CSI) is a significant technique known for being the best treatment for central nervous system (CNS) malignant cancers. As a particularly challenging technique, CSI requires the junction of multiple fields, The CSI technique is most often used in pediatric patients in whom long-term radiation toxicity is of concern. Typically two lateral cranial fields are rotated to match the divergence of the posterior spinal field Materials and Methods: A new approach to reduce the effect of beam divergence was investigated. In the new method, two IMRT fields with beam-divergence match were employed to compensate the dose inhomogeneity due to different SSD. Based on a phantom torso, plans were created for the new IMRT method and compared with the conventional technique. Results: Both new techniques can improve the dose homogeneity of spinal cord. When normalizing the mean dose to 180 cGy, the minimum dose is approximately 168 cGy for all three plans; however, the maximal cord doses are quite different: 237, 204 and 201 cGy for the conventional, 4-field and IMRT plans respectively. The maximal body dose is 269, 214 and 216 cGy and the volume received a dose >200 cGy is 128, 78 and 42 cm3, respectively. Conclusion: The new IMRT technique with matching beamdivergence has been developed for CSI to effectively reduce hot/ cold spots and improve the dose uniformity in the spinal cord. The two-field IMRT technique has the greatest potential and is feasible to be implemented clinically. The remarkable improvement in dose coverage with the beam-divergence matching techniques warrants further studies with more patient data
Working Paper nº 01/17 Margin Call: What if John Tuld were Christian? Thomistic Practical Wisdom in Financial Decision- Making Margin Call: What if John Tuld were Christian? Thomistic Practical Wisdom in Financial Decision-Making
No full textABSTRACT Margin Call is a film depicting the high-tension 32 hours of an investment bank that discovers that its financial holdings are essentially worthless because it has become highly overexposed in the risky trading of mortgage-backed securities and the entire market is set to implode, triggering what the bank leaders know will be a global financial crisis. In a ten-minute overnight meeting, the CEO, John Tuld, must make a difficult choice for the firm and for himself. This paper aims at analyzing Tuld's behavior in the light of the virtue of prudence as described by Thomas Aquinas, and reflects on how the problem might have been handled differently if John Tuld had been guided by Christian moral teachings. It also examines whether Christian ethics, with its ancient heritage, has sufficient specificity and transformative capacity to serve as a guide in contemporary financial decision-making
Local analytic reduction of families of diffeomorphisms
No full textWe study local analytic simplification of families of analytic maps near a hyperbolic fixed point. A particularly important application of the main result concerns families of hyperbolic saddles, where Siegel's theorem is too fragile, at least in the analytic category. By relaxing on the formal normal form we obtain analytic conjugacies. Since we consider families, it is more convenient to state some results for analytic maps on a Banach space; this gives no extra complications. As an example we treat a family passing through a 1 : −1 resonant saddle
Critical Review Joining the Loops: b-Globin Gene Regulation
Get PDFSummary The mammalian b-globin locus is a multigene locus containing several globin genes and a number of regulatory elements. During development, the expression of the genes changes in a process called ''switching.'' The most important regulatory element in the locus is the locus control region (LCR) upstream of the globin genes that is essential for high-level expression of these genes. The discovery of the LCR initially raised the question how this element could exert its effect on the downstream globin genes. The question was solved by the finding that the LCR and activate globin genes are in physical contact, forming a chromatin structure named the active chromatin hub (ACH). Here we discuss the significance of ACH formation, provide an overview of the proteins implicated in chromatin looping at the b-globin locus, and evaluate the relationship between nuclear organization and b-globin gene expression. IUBMB IUBMB Life, 60(12): 824-833, 200
End User Computing and Information Security: a retrospective look at the de- centralisation of data processing and emerging organisational information risk
Get PDFAbstract (around 150 words -style 'Abstract Title') Information security assured on centralised systems through application of principles previously established for paper-based systems
QUALITY FEATURES OF SOME OATS GENOTYPES CULTIVATED IN DIFFERENT SYSTEMS OF PRODUCTION
No full textAbstract The aim of this investigation was to determine the diff erences in quality features of oats in the system of conventional and organic production. The tests were performed during 2005, 2006 and 2007 with fi ve oats populations, of which four were domestic, one population was introduced from Bulgaria and three oats varieties were introduced from Serbia. The quality of oats, especially the chemical composition of the grain in the tested genotypes, irrespective of years, varieties and climate conditions, and depending on the applied system of production was better when it was produced organically. In organic production, the absolute protein content was higher by 0.18% and the relative protein content by 1.4% than the protein content in conventional production. The absolute cellulose content was smaller by 0.69% and the relative cellulose content by 5.8% than the cellulose content in conventional production. In organic production, the absolute and relative content of no nitrogen extractive substances (B.E.M.) were higher by 0.82% and 1.5% respectively than in conventional production. For production expansion, the variety Lovkjen can be recommended as the most suitable variety, and the populations Trebenishta and Bulgaria in terms of quality for organic production. For conventional production the varieties Lovkjen and Rajac can be recommended in terms of quality. The system of organic production -a good method for the production of oats intended for processing for human consumption
Real-Time Implementation of Intelligent Control and Internet Based Remote Activation of Simple Mechatronic Devices in the UMESMAL
No full textABSTRACT In this paper digital control solutions for speed control of direct current motor and level control of dual water tank system are described using conventional control algorithms such as ( PID ( Proportional + Integral + Derivative) and PI ( Proportional + Integral)) as well as intelligent control algorithms based on fuzzy logic. Appropriate software tools are used to allow remote activation of the systems. Observation of the system behavior from remote terminals is made possible using novel tele-reality capability. This capability allows realistic CAD (Computer Aided Design) drawings that accurately represent the physical systems on the remote terminals to exhibit appropriate motion corresponding to the actual movement of the physical system in the University of Maryland Eastern Shore Mechatronics and Automation Laboratory (UMESMAL).
Pen force emulating robotic writing device and its application
No full textAbstract The paper describes our studies on the influence of physical and biomechanical processes on the ink trace and aims at providing a solid foundation for enhanced signature analysis procedures. By means of a writing robot, simulated human handwriting movements are considered to study the relation between writing process characteristics and ink deposit on paper. Since the robot is able to take up different writing instruments like pencil, ballpoint or fine line pen, the type of inking pen was also varied in the experiments. The results of analyzing these artificial ink traces contribute to a better understanding of the underlying interaction processes and will find its applications in the teaching, training, and medical diagnostics. It comes out that position, velocity and pen force suffice to produce high quality ink traces, hardly distinguishable from original probes
ANTI-PROLIFERATIVE AND ANTIOXIDATIVE ACTIVITIES OF THAI NONI/ YOR (MORINDA CITRIFOLIA LINN.) LEAF EXTRACT
No full textAbstract. In this study the leaves of the Thai noni/Yor, (Morinda citrifolia Linn.) were extracted by several methods and evaluated against human cancer cell lines: KB (human epidermoid carcinoma), HeLa (human cervical carcinoma), MCF-7 (human breast carcinoma) and HepG 2 (human hepatocellular carcinoma) cell lines as well as a Vero (African green monkey kidney) cell line, employing the MTT colorimetric method, comparing it to damnacanthal, rutin, and scopoletin. The dichloromethane extract of the fresh leaf showed a better inhibitory effect against KB and HeLa cells with IC 50 values of 21.67 and 68.50 µg/ml, respectively. The dichloromethane extract of dried leaves revealed cytotoxicity against the KB cell line with an IC 50 value of 39.00 µg/ml. Other extracts, as well as rutin and scopoletin, showed reduced anti-proliferative effects on all cancer cell lines (IC 50 103 to over 600 µg/ml). Interestingly, the damnacanthal had potent cytotoxicity against all cancer cell lines and Vero cell lines. These results suggest Thai noni extracts may be safer than the pure compounds, due to their higher safety ratios, which is a good indicator for possible cancer treatment. Several non-aqueous extracts from the leaves showed antioxidant properties, giving IC 50 values of 0.20-0.35 mg/ml. It can be concluded the leaves of M. citrifolia may have benefit as a food supplement for chemoprevention against epidermoid and cervical cancers