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41.
Cindy Jong Joseph J. Pedulla Emilie Mitescu Reagan Yves Salomon‐Fernandez Marilyn Cochran‐Smith 《School science and mathematics》2010,110(6):309-326
This study examined the classroom practices of beginning elementary school teachers' instruction of mathematics and how it connected to their pupils' learning. The Reformed Teaching Observation Protocol (RTOP) was used to measure the extent to which beginning teachers used reformed teaching practices. As a measure of pupil learning, we utilized assessment scores specific to the mathematics unit observed and correlated them with teachers' RTOP scores. We found that beginning teachers who implemented reformed teaching practices tended to have pupils who scored higher on the district mathematics test with a statistically significant correlation of 0.56 (p < .05). Implications of these findings and others are discussed in terms of using the RTOP to improve practice at the elementary school level and for future school‐based research. 相似文献
42.
Following analogous constructions for Lie algebras, we define Whittaker modules and Whittaker categories for finite-dimensional simple Lie superalgebras. Results include a decomposition of Whittaker categories for a Lie superalgebra according to the action of an appropriate sub-superalgebra; and, for basic classical Lie superalgebras of type I, the construction of Whittaker modules from Whittaker modules for the even part. 相似文献
43.
Séverine Dubuisson Christophe Gonzales Xuan Son Nguyen 《International Journal of Approximate Reasoning》2013,54(7):934-953
In this paper, we address the problem of complex object tracking using the particle filter framework, which essentially amounts to estimate high-dimensional distributions by a sequential Monte Carlo algorithm. For this purpose, we first exploit Dynamic Bayesian Networks to determine conditionally independent subspaces of the object’s state space, which allows us to independently perform the particle filter’s propagations and corrections over small spaces. Second, we propose a swapping process to transform the weighted particle set provided by the update step of the particle filter into a “new particle set” better focusing on high peaks of the posterior distribution. This new methodology, called Swapping-Based Partitioned Sampling, is proved to be mathematically sound and is successfully tested and validated on synthetic video sequences for single or multiple articulated object tracking. 相似文献
44.
Emilie Petit Rémi Jacquet Laurent Pouységu Denis Deffieux Stéphane Quideau 《Tetrahedron》2019,75(5):551-560
The reasons for the loss of characteristic odoriferous thiols during the aging of wine in oak-made barrels and subsequent storage in bottles have been in part attributed to covalent capture of these thiols by polyphenolic wine components that are dehydrogenated into electrophilic ortho-quinones upon wine oxygenation. Herein, FeCl3 was used as oxidant in oxygen-deprived aqueous solutions to dehydrogenate grape (epi)catechins and oak ellagitannins in the presence of two typical odoriferous thiols, 2-furanmethanethiol (2FMT) and 3-sulfanylhexan-1-ol (3SH). The preparative-scale conditions used enabled the isolation of six novel 2FMT-bearing (epi)catechin derivatives, three known 3SH-bearing catechin derivatives (the structures of two of those were revised to be strictly derived from 1,6-conjugate addition), three novel 2FMT-bearing castalagin derivatives, and one novel 3SH-bearing castalagin derivative. The structures of these castalagin-based thio-adducts revealed that the capture of thiols by the different dehydrogenated pyrogallol rings of castalagin starts at ring IV, then ring III, and finally ring V. 相似文献
45.
Franceschini E Yu FT Cloutier G 《The Journal of the Acoustical Society of America》2008,123(4):EL85-EL91
The analysis of the ultrasonic frequency-dependent backscatter coefficient of aggregating red blood cells reveals information about blood structural properties. The difficulty in applying this technique in vivo is due to the frequency-dependent attenuation caused by intervening tissue layers that distorts the spectral content of backscattering properties from blood microstructures. An optimization method is proposed to simultaneously estimate tissue attenuation and blood structure factor. With in vitro experiments, the method gave satisfactory estimates with relative errors below 22% for attenuations between 0.101 and 0.317 dBcmMHz, signal-to-noise ratios>28 dB and kR<2.7 (k being the wave number and R the aggregate radius). 相似文献
46.
Gaëtan Compère Emilie Marchandise Jean-François Remacle 《Journal of computational physics》2008,227(3):1923-1942
An anisotropic adaptation process is applied to a three-dimensional incompressible two-phase flow solver. The solver uses a level set/finite element method on unstructured tetrahedral meshes. We show how the level set function can be used to build an anisotropic mesh with good properties. Some computations with a strong transient character and large densities ratios (1/1000) are presented. We show that the efficiency of the computations can be deeply enhanced by mesh adaptations. 相似文献
47.
Bethelihem Mekonnen Xavier Cheseto Christian Pirk Abdullahi Yusuf Sunday Ekesi Emilie Deletre Baldwyn Torto 《Molecules (Basel, Switzerland)》2021,26(4)
The African weaver ant, Oecophylla longinoda, is used as a biological control agent for the management of pests. The ant has several exocrine glands in the abdomen, including Dufour’s, poison, rectal, and sternal glands, which are associated with pheromone secretions for intra-specific communication. Previous studies have analyzed the gland secretions of Dufour’s and poison glands. The chemistry of the rectal and sternal glands is unknown. We re-analyzed the secretions from Dufour’s and poison glands plus the rectal and sternal glands to compare their chemistries and identify additional components. We used the solid-phase microextraction (SPME) technique to collect gland headspace volatiles and solvent extraction for the secretions. Coupled gas chromatography–mass spectrometry (GC-MS) analysis detected a total of 78 components, of which 62 were being reported for the first time. These additional components included 32 hydrocarbons, 12 carboxylic acids, 5 aldehydes, 3 alcohols, 2 ketones, 4 terpenes, 3 sterols, and 1 benzenoid. The chemistry of Dufour’s and poison glands showed a strong overlap and was distinct from that of the rectal and sternal glands. The different gland mixtures may contribute to the different physiological and behavioral functions in this ant species. 相似文献
48.
Inside Back Cover: Control over Nanostructures and Associated Mesomorphic Properties of Doped Self‐Assembled Triarylamine Liquid Crystals (Chem. Eur. J. 5/2015) 下载免费PDF全文
49.
50.
Emilie V. Banide Helge Müller-Bunz Michael Casey M. Cristina Lagunas Michael J. McGlinchey 《Journal of organometallic chemistry》2008,693(10):1759-1770
Successive treatment of 9-(phenylethynyl)fluoren-9-ol (1a), with HBr, butyllithium and chlorodiphenylphosphine furnishes 3,3-(biphenyl-2,2′-diyl)-1-diphenylphosphino-1-phenylallene (5). Moreover, reaction of 1a directly with chlorodiphenylphosphine yields the corresponding allenylphosphine oxide (6). The allenylphosphine (5), and Fe2(CO)9 initially form the phosphine-Fe(CO)4 complex, 11, which is very thermally sensitive and readily loses a carbonyl ligand. In the resulting phosphine-Fe(CO)3 system, 12, the additional site at iron is coordinated by the allene double bond adjacent to phosphorus; the Fe(CO)3 tripod in 12 exhibits restricted rotation on the NMR time-scale even at room temperature. The corresponding chromium complex, (5)-Cr(CO)5 (9), has also been prepared. The gold complexes (5)-AuCl (13), and [(5)-Au(THT)]+ X−, where (THT) is tetrahydrothiophene, and X = PF6 (14a), or ClO4 (14b), are analogous to the known triphenylphosphine-gold complexes. In contrast, in the (arene)(allenylphosphine)RuCl2 system the allene double bond adjacent to phosphorus displaces a chloride, and the resulting cationic species undergoes nucleophilic attack by water yielding ultimately a five-membered Ru-P-CC-O ruthenacycle (17). Thus, the allenylphosphine (5), reacts initially as a conventional mono-phosphine but, when the metal centre has a readily displaceable ligand such as a carbonyl or halide, the allene double bond adjacent to the phosphorus can also function as a donor. X-ray crystal structures are reported for 5, 6, 11, 12, 13, 14a, 14b and 17. 相似文献