Evaluation of Static Work Capabilities in a Hot Environment

The effects of heat stress on an individual's static work capabilities were investigated. Various indicators of strength and endurance were measured under differing heat stress levels. One measure which exhibited a significant change at higher heat stress levels was a combined strength-endurance measurement involving a series of maximal voluntary contractions throughout a one hour exposure. At 35° C WBGT the decrease in MVC from the beginning of the exposure to the end was 43% compared to only 6% at 18° C WBGT. Core temperature was also monitored throughout each exposure.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

A Human Factors Perspective on Helicopter Human External Loads

Human external loads (HEL) refer to operations where humans are transported while suspended below a helicopter. HEL operations are often required to access remote work sites, to access power lines in need of maintenance and repair, for transport of offshore ship captains, and for rescue operations. This paper reports a human factors investigation of HEL operations and the devices used to secure HELs involved in work (non-rescue) activities. The goal of this investigation was to determine if HEL operations pose a significant safety hazard. Specifically, the paper describes the various devices used to secure HELs, the accident history associated with HELs, and human factors recommendations for the regulation of HEL devices and operations. Review of 616 helicopter accident reports revealed that only 1.5% of the accidents occurred during HEL operations and only 0.5% were directly attributable to the presence of an HEL.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Protective mechanisms and current clinical evidence of hypothermic oxygenated machine perfusion (HOPE) in preventing post-transplant cholangiopathy

The development of cholangiopathies after liver transplantation impacts on the quality and duration of graft and patient survival, contributing to higher costs as numerous interventions are required to treat strictures and infections at the biliary tree. Prolonged donor warm ischaemia time in combination with additional cold storage are key risk factors for the development of biliary strictures. Based on this, the clinical implementation of dynamic preservation strategies is a current hot topic in the field of donation after circulatory death (DCD) liver transplantation. Despite various retrospective studies reporting promising results, also regarding biliary complications, there are only a few randomised-controlled trials on machine perfusion. Recently, the group from Groningen has published the first randomised-controlled trial on hypothermic oxygenated perfusion (HOPE), demonstrating a significant reduction of symptomatic ischaemic cholangiopathies with the use of a short period of HOPE before DCD liver implantation. The most likely mechanism for this important effect, also shown in several experimental studies, is based on mitochondrial reprogramming under hypothermic aerobic conditions, e.g. exposure to oxygen in the cold, with a controlled and slow metabolism of ischaemically accumulated succinate and simultaneous ATP replenishment. This unique feature prevents mitochondrial oxidative injury and further downstream tissue inflammation. HOPE treatment therefore supports livers by protecting them from ischaemia-reperfusion injury (IRI), and thereby also prevents the development of post-transplant biliary injury. With reduced IRI-associated inflammation, recipients are also protected from activation of the innate immune system, with less acute rejections seen after HOPE

Training Characteristics of the Criterion Task Set Workload Assessment Battery

An evaluation of the Criterion Task Set was performed to determine the training requirements for the various tasks. Twenty subjects were divided into four groups. One group trained on all nine tasks in the battery. The other three groups trained on different three-task subsets. All subjects trained for two hours per day on five consecutive days. Response time, accuracy and subjective workload measures were obtained for each trial.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

CMB dipoles and other low-order multipoles in the quasispherical Szekeres model

Several authors have previously shown that a Gpc-scale void based on the spherically symmetric Lemaıˆtre-Tolman-Bondi (LTB) model can provide a good fit to certain cosmological data, including the SNIa data, but it is only consistent with the observed CMB dipole if we are located very close to the center, in violation of the Copernican principle. In this work we investigate the more general quasispherical Szekeres model, which does not include spherical symmetry, in order to determine whether this option may be less constricting. We find that the observer is still constrained to a small region, but it is not as geometrically ''special'' as the center of a LTB void. Furthermore, whereas the quadrupole and octupole near the center of a LTB void are necessarily small, certain Szekeres models can include a significant quadrupole while still being consistent with the observed dipole, hinting that Szekeres models may be able to give an explanation for the observed quadrupole/octupole anomalies

DVB-T2: Optionen für Deutschland

Die zweite Generation des DVB- (Digital Video Broadcasting) Standards für die digitale terrestrische Fernsehausstrahlung (DVB-T2) wurde mit Hilfe eines Toolbox-Konzepts entwickelt. Verglichen mit seinem Vorgänger DVB-T enthält der neue Standard viele neue Algorithmen und ermöglicht eine flexible Parameterauswahl. Die Parameter lassen sich perfekt für jedes Empfangsszenario optimieren, ausgehend vom stationären Empfang mit Dachantennen, bis hin zum portablen oder mobilen Empfang. Viele Länder haben bereits DVB-T2 eingeführt. Die Netze wurden aber vor allem für den stationären Empfang optimiert. Im Gegensatz dazu ist der stationäre Empfang keine relevante Option für eine mögliche Nutzung von DVB-T2 in Deutschland. Eine eventuelle Einführung würde sich auf die Vorteile des terrestrischen Rundfunks im Vergleich zu Satellit und Kabel konzentrieren, d. h die Möglichkeit, mit portablen und mobilen Empfängern TV-Programme zu nutzen. Innerhalb eines umfangreichen Feldversuchs in Norddeutschland wurde die Leistung der unterschiedlichen Parameter-Konfigurationen und der neuen Algorithmen von DVB-T2 z. B. M-PLP (Multiple Physical Layer Pipes), Rotated Constellations, MISO (Multiple Input Single Output) im Detail analysiert. Dieser Beitrag stellt den Modellversuch und dessen Ergebnisse vor, die auf Tausenden von Einzelmessungen beruhen. Darüber hinaus gibt das Dokument einen kurzen Überblick über die optimalen Parameter-Konfigurationen für Deutschland