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991.
Dangour AD Moreno X Albala C Rivera-Marquez A Lera L Villalobos A Morris SS Uauy R 《Food and nutrition bulletin》2005,26(2):190-197
Demographic changes in developing countries have resulted in rapid increases in the size of the older population. As a result, health-care budgets face increasing costs associated with the declining health and function of older people. Some governments have responded to this situation by designing innovative programs aimed at older people. One such program, implemented by the government of Chile, distributes an instant food mix fortified with vitamins and minerals to all persons over 70 years old who are registered by the national health service. The national health service covers approximately 90% of the older population. The program specifically targets nutritional vulnerability and micronutrient deficiency, which are common among poor older people in Chile. We present here the findings of a one-year investigation into all aspects of Chile's program for the elderly. The research included in-depth interviews with policy makers and program implementers, focus group discussions with user groups, analysis of the micronutrient content of the nutritional supplement, and telephone interviews of a random sample of older people. The results demonstrate that there can be a considerable degree of self-targeting within national programs; programs need to be sufficiently flexible to permit periodic protocol change; user groups must be consulted both before and during program implementation; and the design of an effective program evaluation must be in place before program implementation. It is hoped that these results will be useful to policy makers and implementers planning programs aimed at improving the health and function of older people. 相似文献
992.
Ovine casein macropeptide (CMP) was characterized by anion-exchange FPLC and reversed-phase (RP) HPLC. To study heterogeneity (the degree of glycosylation and phosphorylation), CMP was desialylated with neuraminidase and dephosphorylated with acid phosphatase. Following RP-HPLC, the main CMP components were identified using either on-line or off-line mass spectrometry. The most abundant ovine CMP component was a diphosphorylated carbohydrate-free form, followed by one or two monophosphorylated and a non-phosphorylated asialo-aglyco species. Aglyco non-phosphorylated, monophosphorylated and diphosphorylated forms were in the ratio 3:20:77. Only approximately 30% of ovine CMP was glycosylated. Assuming that the monosaccharide fraction of ovine CMP is composed of N-acetylgalactosamine, galactose and N-glycolylneuraminic acid, molecular masses consistent with the presence of CMP containing tetra-, tri-, di- and monosaccharide were identified. 相似文献
993.
Elementary school children, some of whom were nonnative speakers of English, learned to add and subtract integers in a discovery-based multimedia game either with or without verbal guidance in English or optionally in Spanish (Groups G--verbal guidance and No-G--no verbal guidance, respectively). Group G members chose to listen to verbal explanations in their first language and showed larger posttest scores than Group No-G. High-computer-experience students in Group G outperformed the rest of the students on training session scores and a transfer test. Longer latencies to respond to practice problems affected all learning measures positively. Results support the use of verbal guidance for discovery-based multimedia games and show that multimedia games may not be equally effective for all learners. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Robust support vector method for hyperspectral data classification and knowledge discovery 总被引:6,自引:0,他引:6
Camps-Valls G. Gomez-Chova L. Calpe-Maravilla J. Martin-Guerrero J.D. Soria-Olivas E. Alonso-Chorda L. Moreno J. 《Geoscience and Remote Sensing, IEEE Transactions on》2004,42(7):1530-1542
We propose the use of support vector machines (SVMs) for automatic hyperspectral data classification and knowledge discovery. In the first stage of the study, we use SVMs for crop classification and analyze their performance in terms of efficiency and robustness, as compared to extensively used neural and fuzzy methods. Efficiency is assessed by evaluating accuracy and statistical differences in several scenes. Robustness is analyzed in terms of: (1) suitability to working conditions when a feature selection stage is not possible and (2) performance when different levels of Gaussian noise are introduced at their inputs. In the second stage of this work, we analyze the distribution of the support vectors (SVs) and perform sensitivity analysis on the best classifier in order to analyze the significance of the input spectral bands. For classification purposes, six hyperspectral images acquired with the 128-band HyMAP spectrometer during the DAISEX-1999 campaign are used. Six crop classes were labeled for each image. A reduced set of labeled samples is used to train the models, and the entire images are used to assess their performance. Several conclusions are drawn: (1) SVMs yield better outcomes than neural networks regarding accuracy, simplicity, and robustness; (2) training neural and neurofuzzy models is unfeasible when working with high-dimensional input spaces and great amounts of training data; (3) SVMs perform similarly for different training subsets with varying input dimension, which indicates that noisy bands are successfully detected; and (4) a valuable ranking of bands through sensitivity analysis is achieved. 相似文献
995.
Carlos Wm. Moreno 《IIE Transactions》1979,11(3):183-197
This paper describes the basic concepts and philosophies of an improved approach to attribute acceptance sampling, which has been tested successfully since 1971. The main measures of performance are expected outgoing quality and expected quality assurance cost. Boundary curves help portray feasibilities of quality-cost combinations, which leads to selections among Pareto optimal sampling plans. Quality and Cost effects are quantified by few parameters which represent situations such as: destructive or nondestructive sampling; effectiveness in finding and correcting defects; reworking vs. scrapping, etc. The model is structured as a Markov Decision Problem, with transition probabilities between sampling stages given by Bayesian estimates, with optimal solutions obtained through Dynamic Programming, with constraints to represent contractual restrictions, and with directed steps to evaluate given sampling plans. Practical applications require computer support. 相似文献
996.
997.
M Friedlander MJ Millward D Bell R Bugat P Harnett JA Moreno L Campbell C Varette V Ripoche L Kayitalire 《Canadian Metallurgical Quarterly》1998,9(12):1343-1345
BACKGROUND: Most patients with advanced ovarian cancer will relapse following platinum-based combination chemotherapy and be considered for second-line treatment. Gemcitabine, a nucleoside analogue, is active against a range of solid tumors. This phase II study investigated the activity of single-agent gemcitabine in patients with recurrent ovarian cancer. PATIENTS AND METHODS: Thirty-eight patients with FIGO stage III (34%) or IV (64%) ovarian cancer who were previously treated with platinum-containing regimens were enrolled. Patients received 1200 mg/m2 gemcitabine on days 1, 8 and 15 of a 28-day cycle. RESULTS: Patients completed an average of 3.6 cycles. Two complete and three partial responses were seen in 36 evaluable patients, for an overall response rate of 13.9% (95% CI: 4.7%-29.5%). The median survival time was 6.7 months. Toxicities were generally mild. The most common were grade 3-4 neutropenia and grade 3 leukopenia reported in 23.7% and 10.5% of patients, respectively. One patient had grade 4 pulmonary toxicity. CONCLUSION: Single-agent gemcitabine is active and well tolerated in patients with recurrent ovarian cancer. 相似文献
998.
999.
1000.
Moreno I 《Applied optics》2004,43(17):3373-3381
The polarization-transforming properties of rotational prisms are analyzed with polarized light by using the Jones calculus and the exact ray-trace. A general expression of the Jones matrix for a rotational prism is derived, incorporating an explicit dependence on the image-rotation angle or the wave-front-rotation angle. The Jones matrix for the Pechan, Dove, Reversion, and Delta prisms is derived where the explicit dependence on the angle of rotation of the image is given. An experiment with a rotating Dove prism is also conducted to determine the output states of polarization for incident linearly polarized light. Experimental results agree with theoretical expectations. 相似文献