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141.
Edelman H. Brock G.W. Carr T. Freeman J. Smith N. 《IEEE transactions on magnetics》1990,26(6):3004-3009
An 8-track magnetic tape head for high-frequency, high-density applications is described. It includes an unshielded magnetoresistive read head and two thin-film record heads for bidirectional operation with write verification. The MR sensors are biased by specially shaped thin-film permanent magnets (PM) that provide fields along both sensor axes to linearize output and eliminate Barkhausen noise. Nearly all films in the head are deposited using dry processes. Deposition conditions for the PM have been optimized to produce a high-coercivity, high-remanence isotropic film. The final head assembly has a contour that utilizes longitudinal slots to achieve intimate contact with low head-to-tape pressure. The associated data channel uses both read and write equalization to obtain the desired output pulse shape from the unshielded head 相似文献
142.
143.
Associations among quantities and concentrations of individual milk proteins and fatty acids were determined in individual milk samples from 233 Holstein cows. Correlation coefficients among the six major proteins and the eleven major fatty acids in bovine milk were grouped hierarchically. Factor analyses grouped the milk components into seven families: fatty acids 4:0-6:0, 6:0-16:0, 16:0, 18:0, 16:1 plus 18:1 plus 18:2, all milk proteins and beta-lactoglobulin alone. Correlation coefficients and groupings by factor analyses coincided with shared pathways of synthesis or genetic origins of milk proteins and fatty acids because they are the basis of the correlation coefficients. Hence, the results from correlations and factor analyses could be used to develop hypotheses for the synthesis of milk components and other coordinately regulated physiological processes. 相似文献
144.
G. J. Freeman X. Le Gourrierec A. Patel M. K. Dawson M. H. B. Powell‐Evans A. J. Skipper C. T. Evans C. A. Boulton C. M. Grimmett J. M. Baron 《Journal of the Institute of Brewing》2003,109(4):309-317
In order to optimise the process of fining beer there is a need to model the process in terms of addition, mixing and flocculation. Mixing of beer and finings has been achieved in a small laboratory stirred vessel that enables exact characterisation of the shear conditions and residence time. The performance of the finings was evaluated after settling in Imhoff cones. Results identified an optimum mixing regime comprising two stages; a relatively vigorous and short duration first mix followed by a longer more gentle mix. 相似文献
145.
The effect of sulphate nutrition on vegetative growth of Brassica juncea and on flavour and allyl isothiocyanate development in the seeds has been investigated using plants grown in sand culture in a glasshouse at six concentrations of sulphate in the nutrient medium. Allyl isothiocyanate was determined by the volumetric method of Raquet and the conclusions were confirmed by a semi-quantitative gas-chromatographic method. Mean fresh and dry weight of plant tops initially increased steeply with increase of sulphate concentration in the nutrient medium to 0.25 mequiv./l and thereafter tended to increase to an asymptotic maximum. Allyl isothiocyanate content of the seeds showed a similar response to changes in levels of sulphate nutrition. The flavour strength of the seeds also increased with increase of their sulphur content. There were highly significant correlation coefficients between total sulphur concentration in the seeds and their allyl isothiocyanate contents. Possible practical consequences of these observations in the mustard industry are briefly discussed. 相似文献
146.
ML Mayer SJ Clark TR Konrad VA Freeman RT Slifkin 《Canadian Metallurgical Quarterly》1999,89(2):164-170
OBJECTIVES: This study assessed the influence of public policies on the immunization status of 2-year old children in the United States. METHODS: Up-to-dateness for the primary immunization series was assessed in a national sample of 8100 children from the 1988 National Maternal and Infant Health Survey and its 1991 Longitudinal Follow-Up. RESULTS: Documented immunization rates of this sample were 33% for poor children and 44% for others. More widespread Medicated coverage was associated with greater likelihood of up-to-dateness among poor children. Up-to-dateness was more likely for poor children with public rather than private sources of routine pediatric care, but all children living in states where most immunizations were delivered in the public sector were less likely to be up to date. Poor children in state with partial vaccine replacement programs were less likely to be up to date than those in free-market purchase states. CONCLUSIONS: While state policies can enhance immunization delivery for poor children, heavy reliance on public sector immunization does not ensure timely receipt of vaccines. Public- and private-sector collaboration is necessary to protect children from vaccine-preventable diseases. 相似文献
147.
A. Rosenqvist M. Shimada B. Chapman A. Freeman G. De Grandi S. Saatchi 《International journal of remote sensing》2013,34(6-7):1375-1387
The Global Rain Forest Mapping (GRFM) project is an international endeavour led by the National Space Development Agency of Japan (NASDA), with the aim of producing spatially and temporally contiguous Synthetic Aperture Radar (SAR) data sets over the tropical belt on the Earth by use of the JERS-1 L-band SAR, through the generation of semi-continental, 100 m resolution, image mosaics. The GRFM project relies on extensive collaboration with the National Aeronautics and Space Administration (NASA), the Joint Research Centre of the European Commission (JRC) and the Japanese Ministry of International Trade and Industry (MITI) for data acquisition, processing, validation and product generation. A science programme is underway in parallel with product generation. This involves the agencies mentioned above, as well as a large number of international organizations, universities and individuals to perform field activities and data analysis at different levels. The GRFM project was initiated in 1995 and, through a dedicated data acquisition policy by NASDA, data acquisitions could be completed within a 1.5-year period, resulting in a spatially and temporally homogeneous coverage to encompass the entire Amazon Basin from the Atlantic to the Pacific; Central America up to the Yucatan Peninsular in Mexico; equatorial Africa from Madagascar and Kenya in the east to Sierra Leone in the west; and south-east Asia, including Papua New Guinea and northern Australia. Over the Amazon and Congo river basins, the project aimed to provide complete cover at two different seasons, featuring the basins at high and low water. In total, the GRFM acquisitions comprise some 13000 SAR scenes, which are currently in the course of being processed and compiled into image mosaics. In March 1999, SAR mosaics over the Amazon Basin (one out of two seasonal coverages) and equatorial Africa (both seasonal coverages) were completed; the data are available on CD-ROM and, at a coarser resolution, via the Internet. Coverage of the second-season Amazon and Central America will be completed during 1999, with the south-east Asian data sets following thereafter. All data are being provided free of charge to the international science community for research and educational purposes. 相似文献
148.
Michael Dixon Robert Glaubius Philip Freeman Robert Pless Michael P. Gleason Matthew M. Thomas William D. Smart 《Machine Vision and Applications》2011,22(5):791-804
We describe a complete system for quantitatively measuring the optical distortion in aircraft windshields and automatically
classifying that distortion as acceptable or not. The system comprises two parts: The first uses digital imaging of a known
grid pattern through the windshield of interest to create a distortion map of that windshield; the second uses the distortion
maps created for 100 windshields (some acceptable and some not) and automatically learns a decision-tree-based classifier.
We show results that highlight the robustness of this system, including a demonstration that the distortion map for a windshield
is consistently measured over 3 years, and cross-validation study shows that we can effectively classify windshields based
on the distortion maps. 相似文献
149.
LL Wang J Blasioli DR Plas ML Thomas WM Yokoyama 《Canadian Metallurgical Quarterly》1999,162(3):1318-1323
Inhibitory receptors on hemopoietic cells critically regulate cellular function. Despite their expression on a variety of cell types, these inhibitory receptors signal through a common mechanism involving tyrosine phosphorylation of the immunoreceptor tyrosine-based inhibitory motif (ITIM), which engages Src homology 2 (SH2) domain-containing cytoplasmic tyrosine or inositol phosphatases. In this study, we have investigated the proximal signal-transduction pathway of an ITIM-bearing receptor, gp49B, a member of a newly described family of murine NK and mast cell receptors. We demonstrate that the tyrosine residues within the ITIMs are phosphorylated and serve for the association and activation of the cytoplasmic tyrosine phosphatase SHP-1. Furthermore, we demonstrate a physiologic association between gp49B and SHP-1 by coimmunoprecipitation studies from NK cells. To address the mechanism of binding between gp49B and SHP-1, binding studies involving glutathione S-transferase SHP-1 mutants were performed. Utilizing the tandem SH2 domains of SHP-1, we show that either SH2 domain can interact with phosphorylated gp49B. Full-length SHP-1, with an inactivated amino SH2 domain, also retained gp49B binding. However, binding to gp49B was disrupted by inactivation of the carboxyl SH2 domain of full-length SHP-1, suggesting that in the presence of the phosphatase domain, the carboxyl SH2 domain is required for the recruitment of phosphorylated gp49B. Thus, gp49B signaling involves SHP-1, and this association is dependent on tyrosine phosphorylation of the gp49B ITIMs, and an intact SHP-1 carboxyl SH2 domain. 相似文献
150.