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11.
This study examined the relationship of several maternal variables to the duration of exclusive breast-feeding and the total duration of breast-feeding, along with attitudes, perceptions, and beliefs about breast-feeding among women living in poor neighborhoods of Managua, Nicaragua. The field work was carried out in December 1992 and January 1993 using qualitative and quantitative methods. A structured questionnaire was administered in interviews with 556 mothers of children under 12 months of age, and meetings of four directed discussion groups were held, in which a total of 20 women participated. At one week of age, almost all the children of the mothers who were surveyed had been breast-fed, but only 45% had been exclusively breast-fed. At 12 weeks old, 30% were already completely weaned. The discussion groups revealed the coexistence of positive opinions about both breast-feeding and bottle-feeding. However, exclusive breast-feeding was considered harmful for the mother, and breast milk was not thought to be sufficient nourishment for the child. Previous experience was strongly related to the duration of exclusive breast-feeding and to total breast-feeding duration. Attitudes, social support, and work situation were important factors influencing the total length of time women breast-fed a child. In general, the results obtained through the interviews and in the discussion groups were in agreement and showed that the elements needed to promote exclusive breast-feeding were social support, a favorable community environment, and policies that dealt with problems faced by working mothers. The complementary research methods were useful for obtaining information about the relative importance of different factors that determine the duration of breast-feeding and for understanding that practice in greater depth from the mother's point of view. 相似文献
12.
Pearton S.J. Ren F. Katz A. Fullowan T.R. Abernathy C.R. Hobson W.S. Kopf R.F. 《Electron Devices, IEEE Transactions on》1992,39(1):154-159
The use of rapid isothermal processing (RIP) is detailed for each of the three annealing steps in the fabrication of heterostructure-based devices such as heterojunction bipolar transistors (HBTs). RIP can be used for the alloying of ohmic metal contacts, annealing of ion-bombarded regions for device isolation or parasitic capacitance reduction, and for conventional implant activation annealing. High-speed (f T=65 GHz) HBTs were achieved using RIP for all of the required heating steps. The authors compare the use of several types of silicon carbide-coated graphite susceptors for eliminating slip formation on 2- and 3-in-diameter GaAs wafers during high-temperature implant activation annealing 相似文献
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Strain endurance experiments on a filled elastomer were performed at several temperatures. It was found that superimposed prestraining accelerated the ageing process. This process was caused by microstructural changes in the elastomer. In order to evaluate the mechanical properties of a filled elastomer it is necessary to take into consideration not only the ageing effects but also the loading history. 相似文献
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J Katz 《Canadian Metallurgical Quarterly》1993,53(3):243-245
We report a case of myasthenia gravis in a young Melanesian woman. It is only the second case described from Papua New Guinea and the first in which antibodies to the acetylcholine receptor have been demonstrated. The patient's complaint of occasional dysarthria was initially dismissed as hysterical in nature due to her apparent normal speech on conversation. The true nature of her problem only became apparent when she was asked to read a prolonged monologue. Myasthenia gravis may present without involvement of the eye muscles and the diagnosis may only become apparent if muscle groups are specifically tested for fatiguability. 相似文献
17.
Howard R. Moskowitz Michele Reisner Barbara Itty Rachel Katz Bert Krieger 《Food quality and preference》2006,17(7-8):536-551
Innovation is often left to insight and serendipity. A lot of what researchers call innovation is actually a process by which one can make the individual consumer or practitioner more ‘creative’. Although it is important to work with the creative individual in hopes of coming up with the better ‘idea’ and new product/service opportunity, an equally valid albeit novel and counterintuitive approach systematizes creativity in a ‘research-driven machine’. This paper presents an approach to the systematization, based upon the point of view that creativity and innovation comprise the recombination of components into new blends. Given this point of view, to then spur innovation requires a systematic database that the user can access, with tools to help manipulate that database. The paper shows how such a database can be constructed and then used to create a novel product. The approach provides a general framework for the sensory professional to become more involved in the early stages of product development, where the focus is on the conceptual aspects of food features rather than on their physical manifestations in actual products. 相似文献
18.
DavidKatz TomaszLukasiak RickGentile 《世界电子元器件》2003,(6):27-30
如今的数字信号处理器(DSP)在性能、外围设备集成、功耗和成本方面都具备很多优势,很多系统设计人员希望在原有系统设计中利用DSP获得比传统处理器更好的效益。但其中一个 相似文献
19.
Katz D.S. Piket-May M.J. Taflove A. Umashankar K.R. 《Antennas and Propagation, IEEE Transactions on》1991,39(8):1203-1212
The application of the finite-difference time-domain (FDTD) method to various radiating structures is considered. These structures include two- and three-dimensional waveguides, flared horns, a two-dimensional parabolic reflector, and a two-dimensional hyperthermia application. Numerical results for the horns, waveguides, and parabolic reflectors are compared with results from using the method of moments (MM). The results for the hyperthermia application are shown as extensions of the previously validated models. This new application of the FDTD method is shown to be useful when other numerical or analytic methods cannot be applied 相似文献
20.
DovidKotz TomaszLukasiak RickGentile 《世界电子元器件》2005,(6):44-46
在嵌入式应用中。随着“开源”C/C 代码越来越成为流行的用于替代基于版权算法的另一选择,挑战也随之而来。其中,最重要的问题是如何优化代码.使其在选定的处理器中更好地运行。本文将探讨开源算法在Blockfin处理器上的移植以及代码优化。 相似文献