A wide-bandwidth low-noise InGaAsP-InAlAs superlattice avalanchephotodiode with a flip-chip structure for wavelengths of 1.3 and 1.55μm

The authors reports the fabrication of a flip-chip InGaAsP-InAlAs superlattice avalanche photodiode using gas source molecular beam epitaxy. The incident light reaches the InGaAs photoabsorption layer through the InP substrate and an InGaAsP-InAlAs superlattice multiplication region which are transparent for wavelengths of 1.55 and 1.3 μm. The light reflection by the electrode enables the absorption layer to be as thin as 0.8 μm without significantly reducing the quantum efficiency. A maximum bandwidth of 17 GHz was obtained at a low multiplication factor because the transit time through the absorption layer is reduced     

Psychiatric diseases and their treatment in general practice in Germany. Results of a World Health Organization (WHO) study

As part of an international study initiated by the World Health Organization (WHO) about psychological disorders in primary health care, patients in the Federal Republic of Germany were compared with patients in other European centres. Patients from Germany do not differ from other European patients in respect to sociodemographic variables or psychiatric disorders. The most frequent CIDI-based diagnoses recorded in patients attending general practices are current depressive episodes (8.6%), generalized anxiety disorders (8.5%), neurasthenia (7.5%), and alcohol dependence (6.3%). In 20.9% of the patients at least one psychiatric diagnosis based on ICD-10 was recorded. In Germany significantly lower global ratings of health status are given than in other European centres although there is no difference in diagnostic prevalence rates. The recognition rate, i.e. the agreement between the CIDI-based ICD-10 diagnoses and the recognition as a case by the physician, is 56.2%-60.2%. On the other hand, the CIDI detects 90% of the patients described as psychologically ill by the physicians if subthreshold cases are also counted, or 46.4% if only defined diagnoses are taken into account. There is a significant correlation between severity of the psychiatric disorder and disability in social functioning. In Mainz and in the other European countries the disability rate of patients with a well-defined disorder is between 67.0% and 72.7%, whereas in Berlin this relation is not as clear, because especially in East Berlin there is a higher rate of unemployment in view of the political situation. Drug treatment is prescribed for 16.1% of the patients in primary care for psychiatric disorders. Half the patients recognized by physicians as cases receive medication. In the rest of Europe patients receive significantly more tranquillizers than in Germany, where the use of herbal drugs is more wide spread.     

Solid-state13C NMR investigations of insoluble deposits in aromatic bitters

Insoluble deposit formed in aromatic bitters produced from alcoholic extracts of about 30 different botanical materials with a dry matter content of 1.67% and 38 vol% alcohol and a characteristic astringent flavour was shown by¹³C NMR spectroscopy to be a coprecipitate of plant polyphenols, proteins and carbohydrates. The polyphenols in the deposit were flavonoids such as anthocyanidins and anthocyanins, with glucose as the principal carbohydrate and derivatives of cinnamic acid. The deposit formation in the aromatic bitters was accelerated by addition of the radical initiator 2,2′-azobis(2-amidinopropane) dihydrochloride or by addition of hydrogen peroxide in combination with iron(III) nitrate and ascorbic acid as a Fenton reagent. Polymerization of catechin and pelargonidin was shown, in model experiments, to be oxidative and to be accelerated by exposure to light. A mechanism involving oxidative polymerization of polyphenols followed by coprecipitation of polymerized polyphenols, proteins and carbohydrates is proposed for formation of deposits in alcoholic beverages of the bitters type.     

Ba（Mg1／3Ta2／3）O3微波陶瓷的损耗研究

本工作用ＸＲＤ，ＥＰＭＡ，ＳＥＭ等测试技术计算和示出了用不同活性粉料制备的Ｂａ（Ｍｇ１／３Ｔａ２／３）Ｏ３微波陶瓷晶格中Ｂ位离子有序度和元素的面分布情况，对它们在Ｘ面下的电行为作了探讨。实验结果表明，ＢＭＴ陶瓷的微波损耗主要与其密度有序度和微观结构的均一度有关。     

Hierarchical production control for a flow shop with dynamic setup changes and random machine breakdowns

In this paper, we study a manufacturing system consisting of two machines separated by two intermediate buffers, and capable of producing two different products. Each product requires a constant processing time on each of the machines. Each machine requires a constant non-negligible setup change time from one product to the other. The demand rate for each product is considered to be piecewise constant. Each machine undergoes failure and repair. The time-to-failure and time-to-repair are exponentially distributed random variables. The setup change and processing operations are resumable. We model our system as a continuous time, continuous flow process. An optimal control problem is formulated for the system to minimize the total expected discounted cost over an infinite horizon. To determine the optimal control policy structure, a discrete version of the problem is solved numerically using a dynamic programming formulation with a piecewise linear penalty function. A real-time control algorithm is then developed with the objective of maintaining low work-in-process inventory and keeping the production close to the demand. The algorithm uses a hierarchical control structure to generate the loading times for each product on each machine in real time and to respond to random disruptions in the system. The system is simulated using this algorithm to study its performance. The performance of the algorithm is also compared to alternative policies.     

Patellar instability in children

Current work on disease states involving the patella has led to increased interest in patellar instability. We reviewed a series of patellar luxations. True trauma-induced luxations are rare. Most cases are recurrent luxations in subjects with a morphological anomaly of the knee extensor system. Because of the growth cartilages, selective therapeutic techniques are needed to stabilize the patella. Recurrent or permanent luxations of the patella result from congenital malformations of the muscles or skeleton. A complete MRI study is highly indicated. The patella can be correctly realigned by surgical release. In cases with femoropatellar dysplasia, which is not specific for children, well conducted rehabilitation therapy often leads to favourable outcome.     

Energy expenditure in workers who install plastic and metal pipes for water supplies and sewage

Since 1985, many drug abuse treatment centers and health care providers have implemented special education programs for individuals who inject drugs. They focus primarily on increasing awareness of the threat of the human immunodeficiency virus (HIV) being spread through drug injection equipment and by sexual activities. As part of the Drug Abuse Treatment for AIDS-Risk Reduction (DATAR) project, the AIDS/HIV Risk Reduction Module was designed to meet these special intervention needs. This study examined program impact on 110 methadone treatment clients. Results indicated that for those in treatment less than 4 months, the AIDS intervention program enhanced specialized knowledge about AIDS, aided in the reduction of AIDS-risky behaviors, and enhanced attitudes toward achieving and maintaining abstinence from drug use. Thus, AIDS education and intervention programs appear to be effective and should be emphasized in the early phase of drug abuse treatment.