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1.
Multiple forms of a symbol-digit substitution task were used to provide a componential analysis of age differences in coding task performance. The results demonstrated age differences in feature encoding, memory, and visual search. A 2nd experiment was conducted with young adults to investigate a sensory deficit as a locus of age differences. The spatial contrast sensitivity deficit of older adults was simulated on forms by applying a digital filter. Persons in the age-simulated contrast condition performed worse than those in the normal contrast condition. The stimulus degradation effect was linked to visual search speed. The study illustrates the utility of componential analysis and offers direct support for the hypothesis that sensory deficits affect performance on tasks used to assess intelligence (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Benjamin D. Deacon A. Cecil Wamble 《Journal of the American Oil Chemists' Society》1954,31(7):284-287
Conclusions A procedure for the analysis of cottonseed and its products for Vitamin E has been developed and improved. The present procedure
generally gives good checks on duplicate analyses.
The Vitamin E content of whole cottonseed is somewhat more a function of variety than of locality. The 1952 crop of cottonseed
contained more Vitamin E than the 1951 crop. The two crops averaged 84 g. per ton and 68.5 g. per ton, respectively.
Most recent results show that there is no loss of Vitamin E in the storage of cottonseed or during the processing of the seed
for its oil and other products.
The hexane-soluble portion of a methanol extract of rolled or cooked cottonseed meats contains Vitamin E in concentrations
that have exceeded the values reported for wheat germ oil, the present commercial source.
A sample of commercial solvent extracted cottonseed meal was found to contain considerably less Vitamin E than hydraulic-
or screw-pressed meals.
The Vitamin E research described in this writing was conducted as a cooperative project of the Texas Engineering Experiment
Station and the Cotton Research Committee of Texas. 相似文献
3.
Declan C. Nolan Chris M. Tierney Cecil G. Armstrong Trevor T. Robinson Jonathan E. Makem 《Engineering with Computers》2014,30(4):689-701
The creation of idealised, dimensionally reduced meshes for preliminary design and optimisation remains a time-consuming, manual task. A dimensionally reduced model is ideal for assessing design changes through modification of element properties without the need to create a new geometry or mesh. In this paper, a novel approach for automating the creation of mixed dimensional meshes is presented. The input to the process is a solid model which has been decomposed into a non-manifold assembly of smaller volumes with different meshing significance. Associativity between the original solid model and the dimensionally reduced equivalent is maintained. The approach is validated by means of a free-free modal analysis on an output mesh of a gas turbine engine component of industrial complexity. Extensions and enhancements to this work are also discussed. 相似文献
4.
Wax esters were isolated from commercial orange roughy (Hoplostethus atlanticus) oil by column chromatography and fractionated by argentation thin layer chromatography. Following transesterification, the
resultant fatty acid methyl esters and fatty alcohols were analyzed by gas chromatography. both acyl- and alkyl-moieties were
mainly of the monoene structure within the 16∶1–22∶1 range. After derivatization, the positions of the double bonds of even
numbered fatty acid and fatty alcohol isomers were located by chromatography-mass spectrometry and compared.
Results of these positional analyses indicate that the primary desaturation reactions takes place in the Δ9 position of pre-existing
(C14 to C24) acyl chains. It is proposed that acyl components from 18∶1 are subjected to chain elongation to form a mixture of 24∶1 isomers
as the final product. Apart from the 24∶1 acyl moiety of the wax esters, in which the double bond was almost exclusively in
the Δ15 position, de novo biosynthetic reactions on acids and alcohols appear to yield related acyl- and alkyl-moieties of
resynthesized wax esters. 相似文献
5.
C.David Harris Andrew J Holder J.David Eick Cecil C Chappelow J.W Stansbury 《Journal of molecular graphics & modelling》2000,18(6)
The GIAO-SCF method for calculating isotropic nuclear magnetic shielding values has been utilized to explain certain features in the 1H-NMR spectrum of 2-methylene-8,8-dimethyl-1,4,6,10-tetraoxaspiro[4.5] decane. Population distributions of the low-energy conformers based on their ab initio energies were used to produce weighting factors for the individual calculated shielding values to calculate the weighted average of the shielding values for a complete set of conformers. The differences in 1H chemical shifts between the hydrogens of the two methyl groups and between the axial and equatorial hydrogens in 2-methylene-8,8-dimethyl-1,4,6,10-tetraoxaspiro[4.5] decane were shown to be due to energy differences between the chair and boat orientations of the six-membered ring and contribution from a twist-boat conformation. Results suggest a hypothesis that intramolecular differences in chemical shift might be calculated to a greater degree of accuracy than chemical shifts calculated relative to a standard. 相似文献
6.
Manish Goyal Sundar Murugappan Cecil Piya William Benjamin Yi Fang Min Liu Karthik Ramani 《Computer aided design》2012,44(6):537-553
The process of re-creating CAD models from actual physical parts, formally known as digital shape reconstruction (DSR) is an integral part of product development, especially in re-design. While, the majority of current methods used in DSR are surface-based, our overarching goal is to obtain direct parameterization of 3D meshes, by avoiding the actual segmentation of the mesh into different surfaces. As a first step towards reverse modeling physical parts, we extract (1) locally prominent cross-sections (PCS) from triangular meshes, and (2) organize and cluster them into sweep components, which form the basic building blocks of the re-created CAD model. In this paper, we introduce two new algorithms derived from Locally Linear Embedding (LLE) (Roweis and Sauk, 2000 [3]) and Affinity Propagation (AP) (Frey and Dueck, 2007 [4]) for organizing and clustering PCS. The LLE algorithm analyzes the cross-sections (PCS) using their geometric properties to build a global manifold in an embedded space. The AP algorithm, then clusters the local cross sections by propagating affinities among them in the embedded space to form different sweep components. We demonstrate the robustness and efficiency of the algorithms through many examples including actual laser-scanned (point cloud) mechanical parts. 相似文献
7.
Cecil D. Elliott 《Journal of Architectural Education》2013,67(3):35-37
It is a truism that the essential qualities of a work of architecture cannot, since architecture is a visual art, be fully conveyed in words. No one would seriously maintain that this absolves those whose business it is to write or talk about architecture from the obligation to use words with some regard for exactness. Yet all too often we behave as if it did; certain words are bandied about as if all were agreed as to what they meant at any time, whereas in fact they may mean different things at different times, and even different things to different people at one time. Cecil Elliott here takes up the case of one such word, a small but much-abused one, isolating four distinct phenomena which it can denote in an architectural context and pursuing his inquiry beyond the realm of semantics to consider their practical implications for the designer. 相似文献
8.
Matthew L. Breeze Elisa Leyva‐Guerrero Grant R. Yeaman Yelena Dudin Ryan Akel Phil Brune Fred Claussen Cecil Dharmasri Jenny Golbach Rong Guo Carl Maxwell Laura Privalle Hilary Rogers Kai Liu Guomin Shan Michele Yarnall Denise Thiede Nancy Gillikin 《Journal of the American Oil Chemists' Society》2015,92(8):1085-1092
Soybean agglutinin (SBA) protein, also known as soybean lectin, is regarded as an anti‐nutrient due to its negative effect on the ability of monogastric animals to gain weight following consumption of raw soybean seed. Historically, SBA has been measured using a time‐consuming and cumbersome hemagglutination procedure. The objective of our research was to obtain a validated methodology that is precise and accurate in the measurement of SBA while allowing minimally equipped laboratories to effectively conduct the analysis, thus our focus was on evaluating an existing commercially available ELISA, an enzyme‐linked‐lectin‐assay (ELLA), and a hybrid ELISA/ELLA. A new ELLA technique that can detect and quantify lectins was chosen and modified specifically for the quantitation of SBA in soybean seed. The proposed ELLA methodology is similar to a standard sandwich ELISA, and uses polyacrylamide‐linked N‐acetylgalactosamine (Gal–NAc–PAA) for a capture phase and the biotinylated version (Gal–NAc–PAA–Biotin) for detection. Based upon the validation data, the ELLA method can precisely and accurately determine soybean lectin levels in soybean seed. The validated ELLA method was used to quantify SBA in nine commercial soybean varieties introduced between 1972 and 2008 and demonstrated that the natural variability of SBA is subject to the effects of genotype and environment. 相似文献
9.
The observation that the subcutaneous fat of pasture-fed Southdown rams consists of two distinct regions is reported. Fatty
acid composition of fat from the outer and inner regions of subcutaneous tissue taken from the rib region of eight Southdown
rams fed pasture were determined. Relative to the harder inner regions (mean melting point 43.1°C), the softer outer regions
(mean melting point 31.8°C) were shown to contain more 9∶0-, 15∶0-, 17∶0-, 17∶1-, 18∶1-cis and total 18∶1 fatty acids; less 14∶0-, 16∶0-, 18∶0- and 18∶1-trans fatty acids; and a greater variety and a greater concentration of branched-chain components. Proportions of medium chain-length
fatty acids other than 9∶0, did not differ between the layers.
The fatty acid contents of serial samples taken at 1-mm intervals through these tissues were determined. Changes in concentrations
of components among samples were gradual through the tissues. There was no clear connective tissue sheet, as has been reported
for pigs. The inner region of the tissues contains apparently nonrandom fluctuating changes in fatty acid composition. 相似文献
10.