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Science and Technology , 2003, pp. 74–77. Eres M. H., Pound G. E., Jiao Z. et al. Implementation of a grid-enabled problem-solving environment in Matlab, In Future Generation Computer Systems , Elsevier, 2005. pp. 920

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Continuous-flow generation of α-diazosulfoxides results in a two- to three-fold increase in yields and decreased reaction times compared to standard batch synthesis methods. These high yielding reactions are enabled by flowing through a bed of polystyrene-supported base (PS-DBU or PS-NMe2) with highly controlled residence times. This engineered solution allows the α-diazosulfoxides to be rapidly synthesized while limiting exposure of the products to basic reaction conditions, which have been found to cause rapid decomposition. In addition to improved yields, this work has the added advantage of ease of processing, increased safety profile, and scale-up potential.

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Construction industry is in relatively early phase of adopting modern web-based technology, even though the web itself has already moved deep into its second phase. In this paper, common strategic points of key projects addressing the problem of engineering collaboration and communication since the mid 1990s are presented. Following this, common requirements for successful communication in the AEC are outlined and compared against new trends in business that emerged just recently. In addition, most promising technologies and applications are outlined and key predictions for the future are presented.

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Az iskolai bántalmazás (bullying) megelőzése

Prevention of Bullying in School Setting

Educatio
Author: Éva Jármi

Absztrakt:

Bár a bullying jelenségének kiterjedtsége napjainkban még módszertani nehézségek miatt nehezen meghatározható, az oktatási-nevelési intézmények és a társadalom részéről is egyre nagyobb igény körvonalazódik az iskolai bántalmazás megértésére és kezelésére. A hatékony antibullying programok közös jellemzői, hogy prevenciós szemléletűek, hangsúlyozzák az antibullying csoportnormák kialakítását, valamint az ismeretátadás mellett attitűdöt is formálnak és viselkedéses készségeket is fejlesztenek. A tanulmány célja, hogy áttekintést adjon a hazai antibullying gyakorlatokról (pl. ENABLE, KIVA, NyugiOvi): az eddig megvalósultakról és a további fejlesztési irányokról.

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High-performance thin-layer chromatography (HPTLC) is a powerful separation technique which is often overlooked. In this study, we comprehensively assessed the applicability, ease, and performance of HPTLC in combination with densitometry and mass spectrometry (MS) to characterize physalins — relatively polar secondary metabolites from Physalis alkekengi L. HPTLC silica gel plates were evaluated in combination with 14 developing solvents (13 published in the literature). Bonded stationary phases (HPTLC RP-18, RP-18 W, CN F254S) were also tested. Four detection reagents (sulfuric acid, anisaldehyde, 4-dimethylaminocinnamaldehyde (DMACA), and molybdatophosphoric acid) were compared to ascertain which one is the most suitable. For all chromatographic analyses, a commercial standard physalin L and a P. alkekengi L. crude extract were used. In some cases, physalin L standard appeared as two clearly resolved bands on silica plates, but only after derivatization, where sulfuric acid reagent provided the best selectivity and sensitivity. Physalin L standard impurity was found to belong to the physalin family as confirmed by HPTLC–MS/(MS) and nuclear magnetic resonance (NMR) spectroscopy. Compared to high-performance liquid chromatography (HPLC), our HPTLC method showed extremely high sensitivity for standard impurity (ca. 4% determined by NMR) as it was clearly visible on the plate during image analysis after derivatization. Unlike (ultra)-high-performance liquid chromatography ((U)HPLC), HPTLC was also able to separate physalin L standard from its impurity. We show that (HP)TLC is a suitable chromatographic technique for the analysis of physalins and can even surpass the performance of (U)HPLC, namely, due to a wide array of different developing solvents available.

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Thin-layer chromatography of eight essential amino acids has been performed on silica layers with seventeen mobile phases of different composition. The mixed aqueous surfactant solution Triton X-100, 1.0 × 10 −5 m -sodium dodecyl sulfate, 8.1 × 10 −4 m -acetone 1:1:5 ( v/v ) was identified as the best mobile phase for specific separation of lysine. This separation can be successfully accomplished in the presence of impurities such as heavy metal cations, inorganic anions, and aliphatic and aromatic amines. The limit of detection of lysine was 0.5 μg per zone. The method has been used for successful identification of lysine in Astymin (Forte) and Alamine (Forte) capsules.

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Huber P. J. Robust statistics, John Wiley, 1981. Cârstea A., Macariu G. Towards a grid enabled symbolic computation architecture, Pollack Periodica , Vol. 3, No. 2, 2008, pp. 15

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education was to enable them to take up in their place in society. There was something refreshing, in my view, about their demands. The fact that they contend that the process of education should be more than merely learning facts or acquiring knowledge but

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management systems take important role in the development of science (Zimmerman 2002 ). Standardisation of data model used in those systems is necessary in order to enable efficient data exchange between those systems and to enable researchers to find the

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clear information on the positioning of their institutions in relation to the others. In this respect, benchmarking exercises, which enable a given institution to learn from peers, could be highly useful, if, of course, these peer institutions were

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