Recovery of gut-associated lymphoid tissue and upper respiratory tract immunity after parenteral nutrition

OBJECTIVE: The authors characterize the recovery of parenteral nutrition-induced changes in gut-associated lymphoid tissue (GALT) and upper respiratory tract immunity with enteral nutrition and provide further information defining the effects of enteral feeding on mucosal immunity. SUMMARY BACKGROUND DATA: The small intestine plays a prominent role in development and maintenance of mucosal immunity, both intestinal and extraintestinal, primarily through immunoglobulin A (IgA)-mediated mechanisms. Prior research has shown that mice fed total parenteral nutrition (TPN) have reduced GALT T and B cells, the cells responsible for IgA production, as well as impaired upper respiratory tract immunity to viral challenge of previously immunized animals. The recovery of TPN-induced changes in GALT and upper respiratory tract immunity after enteral refeeding is studied. METHODS: Male institute of Cancer Research mice received 5 days of TPN followed by 0 to 4 days of chow. Small intestinal GALT was characterized by flow cytometry. In a second experiment, animals were immunized intranasally with moused-adapted influenza virus. Three weeks later, one group received a 5-day course of TPN followed by enteral refeeding for 5 days. A second group received TPN alone. Both groups were challenged with intranasal virus and killed 40 hours postchallenge to determine viral shedding from the upper respiratory tract. RESULTS: Animals fed TPN only had significantly fewer GALT lymphocytes compared with those chow-fed control subjects. Peyer's patch counts increased after a single day of refeeding, returning to normal levels by 48 hours. Lamina propria counts remained significantly depressed after 24 hours of refeeding, but also returned to normal after 48 hours of refeeding. The T-cell and B-cell populations mimicked total cell patterns. Lamina propria CD4+/CD8+ ratio returned to normal only after 72 hours of refeeding. None of the 9 animals refed enterally for 5 days were positive for viral shedding, compared with 8 of 12 matched TPN-fed animals. CONCLUSIONS: Enteral refeeding after TPN is associated with rapid repletion of GALT cellularity, initially within Peyer's patches and subsequently within the lamina propria. Refeeding corrects the impairment of IgA-mediated upper respiratory tract antiviral immunity occurring with TPN administration. This work further enhances the authors' knowledge of the underlying immunologic differences influenced by routes of nutrition.     

On deadlock-free modular supervisory control of discrete-eventsystems

In this paper the problem of synthesizing deadlock-free modular supervisors for discrete-event systems is discussed. By introducing the d-invariant relation between a pair of supervisors, it is shown that when the control objective is described in terms of intersection of two languages, a necessary and sufficient condition for the modular supervisor to be deadlock-free is that this pair of subsupervisors satisfies a d-invariant relation. A procedure for synthesizing the deadlock-free modular supervisor is presented. Some issues concerning deadlock-free modular supervisory control are also discussed     

铝液夹杂物检测DMIRT－Ⅲ法的试验研究

提出了一种新的铝液夹杂物快速检测方法。导出了该法的检测原理方程。分析并试验研究了影响检测重复性和分辨率的因素。试验选择了较好的检测参数，并获得了较好的检测结果。     

用于多种组装技术的厚膜导体复合结构

厚膜导体Ｐｄ－Ａｇ／Ａｕ、Ｐｔ－Ｐｄ－Ａｕ／Ａｕ平面复合结构，Ｐｄ－Ａｇ／Ａｕ立体复合结构可使多种组装技术相互兼容。立体复合结构还可有效地降低导体线电阻，减少线损耗。而且，其超声键合性尤佳     

一种派生式与创成式相结合的CAPP系统

本文结合为某机械厂开发的实用计算机辅助工艺设计系统(JJCAPP),论述了一种兼有派生式和创成式特点的综合式工艺自动设计方法.     

一种新的环网故障诊断与重构算法

为提高环网的容错性能，文献（1）提出了一种基于事件驱动的故障重构算法，其缺点是该算法只能容忍连线故障。本文给出一种新的采用时钟起时驱动的重构算法，该算法既能容忍连线故障也能容忍站（或节点）故障，且令牌控制较文献（1）的简单。     

Effect of degumming on the tensile properties of silkworm (Bombyx mori) silk fiber

Forcibly reeled silkworm (Bombyx mori) silk was used to study how exposure to a degumming treatment (boiling in distilled water for 30 min) affects tensile properties. Because forcibly reeled and naturally spun fibers exhibit comparable mechanical behavior, the results can be generalized to material obtained conventionally from cocoons. The effects of degumming include: a decrease in the initial elastic modulus, a decrease in the stress at the proportional limit (yield strength), a change in the qualitative shape of force‐displacement curves, and significant qualitative and quantitative variability in force‐displacement data from samples subjected to nominally identical degumming histories. Immersion in water at room temperature or heating in air at 100°C for 30 min are both qualitatively equivalent to a 30‐min degumming treatment in boiling water, in terms of the effect on silk tensile properties. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1431–1437, 2002; DOI 10.1002/app.10366     

Synthesis and characterization of novel copolymers with the trimethylsilyl group for deep‐UV photoresists

N‐(4‐Acetoxyphenyl) maleimide (APMI) and three kinds of comonomers bearing a trimethylsilyl group were copolymerized at 60°C in the presence of azobisisobutyronitrile (AIBN) as an initiator in 1,4‐dioxane to obtain the three IP, IIP, and IIIP copolymers. These copolymers were removed from the acetoxy group in a transesterification process into new IVP, VP, and VIP copolymers with a pendant hydroxyl group. Two modified processes were adopted to prepare photoresists using these copolymers. The first process involved mixing the dissolution inhibitor, o‐nitrobenzyl cholate, with the new copolymers. Second, o‐nitrobenzyl cholate was introduced into the copolymers using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) in dimethylformamide (DMF). The cyclic maleimide structure is responsible for the high thermal stability of these copolymers. After irradiation using deep–UV light and development with aqueous Na₂CO₃ (0.01 wt %), the developed patterns showed positive images and exhibited good adhesion to the silicon wafer without using any adhesion promoter. The resolution of these resists was at least 0.8 μm and an oxygen‐plasma etching rate was 1/5.3 to that of hard‐baked HPR‐204. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2791–2798, 2002; DOI 10.1002/app.10255