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1.
Acrylamide-based holographic recording materials have significant advantages and the composition of these materials has been optimized in terms of energetic sensitivity and diffraction efficiency. As a result, diffraction gratings with an efficiency of almost 80% for energetic exposures of 35 mJ/cm2 and a spatial frequency of 1000 lines/mm in photosensitive films 65 μm thick have been obtained. In this paper we present the effects of intensity, thickness, and variation in the concentration of each component by studying the angular responses of the diffraction gratings recorded in each composition.  相似文献   
2.
Orthogonal arrays are used widely in manufacturing and high-technology industries for quality and productivity improvement experiments. For reasons of run size economy or flexibility, nearly-orthogonal arrays are also used. The construction of orthogonal or nearly-orthogonal arrays can be quite challenging. Most existing methods are complex and produce limited types of arrays. This article describes a simple and effective algorithm for constructing mixed-level orthogonal and nearly-orthogonal arrays that can construct a variety of small-run designs with good statistical properties efficiently.  相似文献   
3.
Abstract

Among the different sources of noise in holography, noise gratings have been analysed extensively in photographic emulsions owing to the granular nature of these recording materials; however, information about photopolymers is quite scarce. The effect of age on transmittance curves in a photopolymer system, used as holographic recording material, shows the appearance of noise gratings. We present a theoretical model, which explains the results for transmittance as a function of time in the presence of noise gratings recorded in an acrylamide mixture photopolymer. Good agreement between theory and experience has been observed, and the model can be used to obtain an approximate value for the diffraction efficiency of noise gratings, as well as to explain the results of age in transmittance curves.  相似文献   
4.
In comparison with HLA-matched sibling bone marrow transplants, unrelated donor transplants are associated with increased graft-versus-host disease and graft failure. This is likely in part due to HLA incompatibilities not identified by current matching strategies. High resolution DNA-based typing methods for HLA class II loci have improved donor selection and treatment outcome in unrelated donor bone marrow transplantation. By using DNA-based typing methods for HLA-A and -B on a cohort of 100 potential bone marrow donor/patient pairs, we find that serological typing for HLA class I is limited in its ability to identify incompatibilities in unrelated pairs. Furthermore, the incompatibilities identified are associated with the presence at high frequency of alloreactive cytotoxic T-lymphocyte precursors. DNA typing also indicates that HLA-C mismatches are common in HLA-A and -B serologically matched pairs. Such mismatches appear to be significantly less immunogenic with respect to cytotoxic T-lymphocyte recognition, but are expected to influence natural killer cell activity. Thus, improved resolution of HLA class I shows many previously undisclosed mismatches that appear to be immunologically functional. Use of high resolution typing methods in routine matching is expected to improve unrelated donor selection and transplant outcome.  相似文献   
5.
This letter introduces two Pade/spl acute/ approximation schemes that, when combined, enable the ABCD parameters of multiconductor transmission lines to be accurately and efficiently evaluated directly in the phase domain for application to harmonic analysis studies. Since the solution is obtained directly in the phase domain, modal decompositions are completely avoided.  相似文献   
6.
OBJECTIVE: Type 2 diabetes is a slowly progressive disease, in which the gradual deterioration of glucose tolerance is associated with the progressive decrease in beta-cell function. Hyperglycemia per se has deleterious effects on both beta-cell function and insulin action, which are partially reversible by the short-term control of blood glucose levels. We hypothesized that the induction of euglycemia, using intensive insulin therapy at the time of clinical diagnosis, could lead to a significant improvement in insulin secretion and action and thus alter the clinical course of the disease. RESEARCH DESIGN AND METHODS: Thirteen newly diagnosed diet-unresponsive type 2 diabetic patients were treated with continuous subcutaneous insulin infusion (CSII) for 2 weeks and followed longitudinally while being treated with diet alone. RESULTS: Four patients were considered therapeutic failures since CSII failed to induce euglycemia (n = 1) or glucose control deteriorated within 6 months after CSII (n = 3). The remaining nine patients were maintained on diet alone with adequate control from 9 to > 50 months (median +/- SE, 26 +/- 4.8 months). In five patients, glycemic control deteriorated after 9-36 months, but a repeat 2-week CSII treatment reestablished control in four patients. One of these patients underwent a third CSII treatment 13 months later. At the time this article was written, six patients of the initial group were still controlled without medication 16-59 months (median +/- SE, 45.5 +/- 6.6 months) after the initiation of treatment. Body weight remained unchanged in all patients. CONCLUSIONS: These findings suggest that in a significant proportion of type 2 diabetic patients who fail to respond to dietary measures, short-term intensive insulin treatment can effectively establish responsiveness, allowing long-term glycemic control without medication. Further studies are required to establish whether simpler treatment regimens could be equally effective. If the hypothesis offered here finds support, present approaches to the management of newly diagnosed type 2 diabetes may need to be revised.  相似文献   
7.
Documentation is generally viewed in a secondary or support role to the sale and function of primary products. The study discusses the relationship between secondary and primary product characteristics and provides the results of a customer survey of computer hardware end users. Over 500 respondents (or customers) were surveyed regarding the impact of documentation on customers' perception of product quality. The results of a logistic regression showed that the level of satisfaction with documentation plays a critical role in explaining customer satisfaction with primary product quality. Consequently, before organizations make decisions regarding cuts in documentation, they should carefully evaluate documentation's effects on company performance. Implications for practice and research are also provided, with follow up and complementary studies suggested  相似文献   
8.
The seed oil ofPolygala virgata (family Polygalaceae) contains 74% of monoacetotriglycerides, the first found in nature with the acetate group in position 2 ofsn-glycerol. Naturally occurring triglycerides characterized previously all have the acetate at position 3. The configuration of the acetoglyceride fromP. virgata was established by a combination of thin layer chromatography, optical rotatory dispersion, and nuclear magnetic resonance. Presented at AOCS Meeting, New York, May 1977.  相似文献   
9.
A range of latex storage and air drying conditions were studied with regard to the proteolytic activity of the dried latex (‘crude papain’). The optimum drying temperature is between 50–55°C, activity losses on drying can be restricted to about 7% under these conditions. The activity of crude papain is the same if it is derived either from exuded latex or from that portion (about 20% of latex yield) which coagulates on the fruit surface on tapping. Latex storage at tropical ambient for 2–24 h prior to drying (with or without exposure to sunlight) causes maximum losses of about 20% in the proteolytic activity of the crude papain. Sodium chloride addition has an anti-coagulating effect on latex and accelerates the later stages of drying. Contrary to earlier reports, this causes a decreased activity in the product, which may be related to changes in latex pH. Addition of EDTA or sodium bisulphite, singly or in combination, protects the latex activity (increases of 20–25% relative to controls).  相似文献   
10.
The yields of fresh papaya latex, dry latex (crude papain) and proteolytic activity were studied with respect to fruit age (1.5–3 months); sex of the tree (those which produce fruit: female and hermaphrodite); time (5:30 a.m.-2:00 p.m.) of latex collection; pattern and frequency of fruit incisions. The yields from 250 randomly selected trees (750 fruits) were investigated under these different conditions. Yields of fresh latex are frequently unreliable guides to yields of proteolytic activity. In contrast to the literature recommendations, the yields of crude papain from female and hermaphrodite trees and during different periods of the day were similar. The proteolytic activity differs significantly with time of collection only with hermaphrodite trees. The proteolytic activity of hermaphrodite crude papain is usually less than that from females (under some conditions only 60% of that from females). Yields of crude papain were higher in older fruits (2.5–3 months) from both sexes. The proteolytic activity of the crude papain was highest in the younger fruits (1.5–2 months) from female trees (30% higher than from older fruits); these activity differences with age were not significant with hermaphrodite trees. No significant differences in crude papain yields were encountered using three or six incisions per fruit at weekly intervals. The optimum procedure is to tap 2.5–3-month-old fruit of both sexes with three incisions between dawn and the start of rains in early afternoon, at about 4-day intervals.  相似文献   
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