Inguinal hernia 1998--an assessment of current status

Hernia surgery has considerably changed in recent years. In the era of minimal invasive surgery classical Shouldice repair has become old-fashioned and is increasingly replaced by tension-free techniques using synthetic mesh material. Currently, Shouldice repair remains the treatment of choice in young patients with small primary hernia. Lichtenstein hernioplasty is indicated in young patients with large hernias, and in those over 35 years of age for any size of hernias. Endoscopic operations are restricted to bilateral primary hernias and recurrent hernias. In future, when used on the basis of a reasonable strategy, the variety of operative procedures offers a chance to improve the results of hernia surgery. Further studies are needed to demonstrate which hernia strategy is most reliable in terms of cost-effectiveness, patient comfort, complication and recurrence rate.     

The Impact of WARC-79 on the Broadcasting-Satellite Service

The World Administrative Radio Conference, Geneva, Switzerland, 1979 (WARC-79) decided many of the international issues facing the Broadcasting-Satellite service (BSS) and adopted Resolutions and Recommendations dealing with most of the others. This paper identifies the BSS issues considered at WARC-79, describes the actions taken during the Conference, indicates the current status of subsequent WARC-mandated activities involving the BSS, and assesses the potential impact of the WARC on future BSS systems.     

Analysis of a simplified calibration procedure for 18 design-phase building energy models

This paper evaluates the accuracy of 18 design-phase building energy models, built according to LEED Canada protocol, and investigates the effectiveness of model calibration steps to improve simulation predictions with respect to measured energy data. These calibration steps, applied in professional practice, included inputting actual weather data, adding unregulated loads, revising plug loads (often with submetered data), and other simple updates. In sum, the design-phase energy models underpredicted the total measured energy consumption by 36%. Following the calibration steps, this error was reduced to a net 7% underprediction. For the monthly energy use intensity (EUI), the coefficient of variation of the root mean square error improved from 45% to 24%. Revising plug loads made the largest impact in these cases. This step increased the EUI by 15% median (32% mean) in the models. This impact far exceeded that of calibrating the weather data, even in a sensitivity test using extreme weather years.     

Densification behavior,microstructure evolution,and wear performance of selective laser melting processed commercially pure titanium

This work presents a comprehensive study of the densification behavior, phase and microstructure development, hardness and wear performance of commercially pure Ti parts processed by selective laser melting (SLM). An in-depth relationship between SLM process, microstructures, properties, and metallurgical mechanisms has been established. A combination of a low scan speed and attendant high laser energy density resulted in the formation of microscopic balling phenomenon and interlayer thermal microcracks, caused by a low liquid viscosity, a long liquid lifetime, and resultant elevated thermal stress. In contrast, using a high scan speed produced the disorderly liquid solidification front and considerably large balling, due to an elevated instability of the liquid induced by Marangoni convection. A narrow, feasible process window was accordingly determined to eliminate process defects and result in full densification. The phase constitutions and microstructural characteristics of SLM-processed Ti parts experienced a successive change on increasing the applied scan speeds: relatively coarsened lath-shaped α → refined acicular-shaped martensitic α′ → further refined zigzag-structured martensitic α′, due to the elevated thermal and kinetic undercooling and attendant solidification rate. The optimally prepared fully dense Ti parts had a very high hardness of 3.89 GPa, a reduced coefficient of friction of 0.98 and wear rate of 8.43 × 10^?4 mm³ N^?1 m^?1 in dry sliding wear tests. The formation of an adherent, plastically smeared tribolayer on the worn surface contributed to the enhancement of wear performance.     

A new modular feeding system and its economic scope of application

Since flexible production systems usually require special technologies and additional components, high costs are the main limitation factor for their flexibility. Therefore, the most economic components have to be chosen for each flexible production system. This paper focuses on automatic feeding systems and starts with a comparison of the flexibility and the feeding rates of the most important flexible feeders available today. To cope with the deficits of flexible feeders with mechanical orientation, a new modular system is presented. In addition, a design method for the different modules of the new feeder is introduced. Finally, a detailed cost analysis determines the economic application of the modular feeder within the presented systems in dependency of the given flexible feeding task.     

The Role of Advanced Glycation End Products and Its Soluble Receptor in Kidney Diseases

Patients with chronic kidney disease (CKD) are more prone to oxidative stress and chronic inflammation, which may lead to an increase in the synthesis of advanced glycation end products (AGEs). Because AGEs are mostly removed by healthy kidneys, AGE accumulation is a result of both increased production and decreased kidney clearance. On the other hand, AGEs may potentially hasten decreasing kidney function in CKD patients, and are independently related to all-cause mortality. They are one of the non-traditional risk factors that play a significant role in the underlying processes that lead to excessive cardiovascular disease in CKD patients. When AGEs interact with their cell-bound receptor (RAGE), cell dysfunction is initiated by activating nuclear factor kappa-B (NF-κB), increasing the production and release of inflammatory cytokines. Alterations in the AGE-RAGE system have been related to the development of several chronic kidney diseases. Soluble RAGE (sRAGE) is a decoy receptor that suppresses membrane-bound RAGE activation and AGE-RAGE-related toxicity. sRAGE, and more specifically, the AGE/sRAGE ratio, may be promising tools for predicting the prognosis of kidney diseases. In the present review, we discuss the potential role of AGEs and sRAGE as biomarkers in different kidney pathologies.