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71.
Eron Leonard; Huesmann Rowell; Spindler Anja; Guerra Nancy; Henry David; Tolan Patrick 《Canadian Metallurgical Quarterly》2002,70(1):179
A multiyear, multicontext aggression prevention intervention was provided during the early or late elementary school years in an inner-city and an urban poor community. Sixteen schools were randomly assigned to 1 of 4 conditions: (a) no-treatment control, (b) general enhancement classroom program, (c) general enhancement plus small-group peer-skills training, or (d) general enhancement plus small-group peer-skills training plus family intervention. This article reports on results for the high-risk subsample of 1,500 children. Results from hierarchical linear modeling indicate that comprehensive interventions, if provided in early grades, can be effective for children in schools in settings with resources adequate to support learning and development, but some unintended effects can occur in schools in the most distressed communities when delivered too late in development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
The metabolism of tammar wallaby (Macropus eugenii) blastocysts was analysed by means of quantitative fluorescence microscopy during embryonic diapause and 2, 3, 4, 5, 8 and 10 days after reactivation to determine nutrient preferences during metabolic reactivation of the blastocyst. The surface area of quiescent blastocysts was 0.16 +/- 0.02 mm2 (mean +/- s.e.m.), and increased to 0.44 +/- 0.04 mm2 (P < 0.05) by Day 8 after removal of the sucking stimulus of the pouch young (RPY). Day-10 blastocysts, analysed over two successive breeding seasons, were significantly different in size from each other (Group A, 1992: 4.44 +/- 1.47 mm2; Group B, 1993: 18.87 +/- 4.62 mm2; P < 0.01), and both groups were significantly different in size from diapausing blastocysts (P < 0.01). There was no significant difference in carbohydrate uptake or production by blastocysts during the first five days after RPY. Glucose uptake by blastocysts recovered 8 days after RPY (61.9 +/- 30.0 pmol embryo-1 h-1) was significantly greater than that by Day-0 blastocysts (17.9 +/- 5.5 pmol embryo-1 h-1) and glucose uptake by both groups of Day-10 blastocysts (Group A, 174.0 +/- 28.4 pmol embryo-1 h-1; Group B, 616.0 +/- 239.0 pmol embryo-1 h-1) was significantly different from that by Day-0 blastocysts (P < 0.01). Pyruvate uptake by Day-10 blastocysts (Group A, 46.0 +/- 32.2 pmol embryo-1 h-1; Group B, 250.0 +/- 136.0 pmol embryo-1 h-1; P < 0.01) increased significantly compared with that by Day-0 blastocysts (6.4 +/- 1.6 pmol embryo-1 h-1; P < 0.01). Lactate production by Day-10 blastocysts (Group A, 186.7 +/- 30.3 pmol embryo-1 h-1; Group B, 285 +/- 129 pmol embryo-1 h-1; P > 0.01) was also significantly different from that by quiescent blastocysts (41.20 +/- 9.6 pmol embryo-1 h-1). There was a linear relationship between surface area and glucose uptake and surface area and pyruvate uptake (r2 = 0.965 and r2 = 0.971 respectively). Despite increases in carbohydrate uptake, there was a proportional decrease in lactate production indicating an increase in oxidative metabolism during reactivation. This suggests that there may be a metabolic switch at, or around, Day 5 after RPY. 相似文献
73.
The application of enantioselective catalytic methods for the technical preparation of chiral agrochemicals is illustrated for three active ingredients of the acylanilide type. The key step for the technical synthesis of the herbicide (S)–metolachlor (trade name DUAL MAGNUM®) is the enantioselective hydrogenation of an imine intermediate using a novel iridium ferrocenyl–diphosphine catalyst that exhibited an unprecedented high activity (average turnover frequency up to 350,000 h-1) with an enantioselectivity of 80%. (R)–metalaxyl and clozylacon were synthesized with > 95% and 99% enantiomeric purity, respectively. The enantioselective hydrogenation of the corresponding enamides with Rh or Ru/binap catalysts was the key step in both cases. Some conclusions regarding the development of the catalyst system are made and important prerequisites for the use of enantioselective catalysts for the production of agrochemicals are discussed. 相似文献
74.
John W. Hamer Andrew D. Arnold Michael L. Boroson Masahiro Itoh Tukaram K. Hatwar Margaret J. Helber Koichi Miwa Charles I. Levey Michael Long John E. Ludwicki David C. Scheirer Jeffrey P. Spindler Steven A. van Slyke 《Journal of the Society for Information Display》2008,16(1):3-14
Abstract— By using current technology, it is possible to design and fabricate performance‐competitive TV‐sized AMOLED displays. In this paper, the system design considerations are described that lead to the selection of the device architecture (including a stacked white OLED‐emitting unit), the backplane technology [an amorphous Si (a‐Si) backplane with compensation for TFT degradation], and module design (for long life and low cost). The resulting AMOLED displays will meet performance and lifetime requirements, and will be manufacturing cost‐competitive for TV applications. A high‐performance 14‐in. AMOLED display was fabricated by using an in‐line OLED deposition machine to demonstrate some of these approaches. The chosen OLED technologies are scalable to larger glass substrate sizes compatible with existing a‐Si backplane fabs. 相似文献
75.
Our purpose was to determine whether hearts from mice bioengineered to lack either the M isoform of creatine kinase (MCK-/- mice) or both the M and mitochondrial isoforms (M/MtCK-/- mice) have deficits in cardiac contractile function and energetics, which have previously been reported in skeletal muscle from these mice. The phenotype of hearts with deleted creatine kinase (CK) genes is of clinical interest, since heart failure is associated with decreased total CK activity and changes in the relative amounts of the CK isoforms in the heart. We measured isovolumic contractile performance in isolated perfused hearts from wild-type, MCK-/-, and M/MtCK-/- mice simultaneously with cardiac energetics (31P-nuclear magnetic resonance spectroscopy) at baseline, during increased cardiac work, and during recovery. Hearts from wild-type, MCK-/-, and M/MtCK-/- mice had comparable baseline function and responded to 10 minutes of increased heart rate and perfusate Ca2+ with similar increases in rate-pressure product (48+/-5%, 42+/-6%, and 51+/-6%, respectively). Despite a similar contractile response, M/MtCK-/- hearts increased [ADP] by 95%, whereas wild-type and MCK-/- hearts maintained [ADP] at baseline levels. The free energy released from ATP hydrolysis decreased by 3.6 kJ/mol in M/MtCK-/- hearts during increased cardiac work but only slightly in wild-type (1.7 kJ/mol) and MCK-/- (1.5 kJ/mol) hearts. In contrast to what has been reported in skeletal muscle, M/MtCK-/- hearts were able to hydrolyze and resynthesize phosphocreatine. Taken together, our results demonstrate that when CK activity is lowered below a certain level, increases in cardiac work become more "energetically costly" in terms of high-energy phosphate use, accumulation of ADP, and decreases in free energy released from ATP hydrolysis, but not in terms of myocardial oxygen consumption. 相似文献
76.
Martin Spindler Wolfgang Büschel Charlotte Winkler Raimund Dachselt 《Personal and Ubiquitous Computing》2014,18(5):1213-1225
Spatially aware handheld displays are a promising approach to interact with complex information spaces in a more natural way by extending the interaction space from the 2D surface to the 3D physical space around them. This is achieved by utilizing their spatial position and orientation for interaction purposes. Technical solutions for spatially tracked displays already exist in research laboratories, e.g., embedded in a tabletop environment. Along with a large stationary screen, such multi-display systems provide a rich design space with a variety of benefits to users, e.g., the explicit support of co-located parallel work and collaboration. As we see a great future in the underlying interaction principles, the question is how the technology can be made accessible to the public. With our work, we want to address this issue. In the long term, we envision a low-cost tangible display ecosystem that is suitable for everyday usage and supports both active displays (e.g., the iPad) and passive projection media (e.g., paper screens and everyday objects such as a mug). The two major contributions of this article are a presentation of an exciting design space and a requirement analysis regarding its technical realization with special focus on a broad adoption by the public. In addition, we present a proof of concept system that addresses one technical aspect of this ecosystem: the spatial tracking of tangible displays with a consumer depth camera (Kinect). 相似文献
77.
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79.
Mark P. Jensen Renato Chiarizia Joseph S. Ulicki Brian D. Spindler Daniel J. Murphy M. Mahmun Hossain 《溶剂提取与离子交换》2013,31(4):329-345
The sterically constrained, macrocyclic, aqueous soluble ligand N,N′-bis[(6-carboxy-2-pyridyl)methyl]-1,10-diaza-18-crown-6 (H2BP18C6) was investigated for separating americium from curium and all the lanthanides by solvent extraction. Pairing H2BP18C6, which favors complexation of larger f-element cations, with acidic organophosphorus extractants that favor extraction of smaller f-element cations, such as bis-(2-ethylhexyl)phosphoric acid (HDEHP) or (2-ethylhexyl)phosphonic acid mono(2-ethylhexyl) ester (HEH[EHP]), created solvent extraction systems with good Cm/Am selectivity, excellent trans-lanthanide selectivity (Kex,Lu/Kex,La = 108), but poor selectivity for Am against the lightest lanthanides. However, using an organic phase containing both a neutral extractant, N,N,N’,N’-tetra(2-ethylhexyl)diglycolamide (TEHDGA), and HEH[EHP] enabled rejection of the lightest lanthanides during loading of the organic phase from aqueous nitric acid, eliminating their interference in the americium stripping stages. In addition, although it is a macrocyclic ligand, H2BP18C6 does not significantly impede the mass transfer kinetics of the HDEHP solvent extraction system. 相似文献
80.
Eleonore Engelmann Gerhard Just Wilhelm Pritzkow Matthias Rudolf Gerald Spindler Tieu Dung Tien Volkmar Voerckel Volker Wittekind 《Advanced Synthesis \u0026amp; Catalysis》1986,328(4):475-483
The mole numbers of the starting paraffins, of the intermediate alcohols and ketones with the same chain lengths, of the lower alkan-2-ones, of the carboxylic acids, and of the esters were determined at different reaction times for the oxidations of n-tridecane, n-tetradecane, and n-pentadecane with molecular oxygen at 140°C in the presence of 0.1% Mn-stearate. In the stationary region of the oxidation about 1.2 moles of acids and 0.7 moles of esters are formed from 1 mole of paraffin consumed. The relative oxidation rates of alcohols and of ketones with reference to the starting paraffins were estimated from the mole numbers of the starting paraffins, the alcohols and the ketones at the maxima of the alcohols and the ketones. These values are higher than those determined by competitive oxidations, and this discrepancy is an indirect evidence of the formation of bifunctional intermediates from the starting paraffins. The relative rates of the formation of alcohols, ketones, and bifunctional products from normal paraffins were estimated. 相似文献