Fatigue among Air crews on (Ultra)-Long-Range flights - A comparison of subjective fatigue with objective concentration ability.

Introduction: Long duty times are common in the aviation industry, especially with the introduction of ultra long range flights (ULR). This article aims to compare the subjective fatigue assessment and concentration ability of flight crews with objective concentration and alertness tests during (U)LR-flights. Method: The study examined different (U)LR-flights. Before, during and after the flights subjective fatigue and concentration ability of the flight crew was examined with visual analog scale and objective attention and concentration ability with the FAIR-2 test respectively the 3-min Psychomotor Vigilance Test. For statistical analysis we used a repeated ANOVA with a post-hoc-analysis and a Wilcoxon signed-rank test for connected samples. Results: In total 28 crew members were examined. Subjective concentration ability declined and fatigue increased significantly over the course of flights. However, no significant changes were observed in the objective concentration tests performed before and after the flights. Conclusions: The study found that fatigue significantly increased with flight time, particularly during night hours at the window of circadian low of the crews. However, objective concentration performance showed no significant deterioration over time. The study's results were consistent with previous research, except for the finding that objective concentration was still stable. The study also compared the findings to another profession and found similar results regarding the performance of complex tasks after long working hours while experiencing fatigue. Pratical applications: This study helps to understand the effects of ultra long-range flight on fatigue and concentration of the air crew and can help to improve safety issues on such flights.

Changes in vital signs, ventilation mode, and catecholamine use during intensive care aeromedical evacuation flights.

Introduction: Especially after (natural) disasters, local health systems are also destroyed or their ability to work is massively restricted. The transport of injured patients is therefore often necessary for further care. Numerous nations keep fixed-wing aircraft with intensive-care capabilities available for secondary transport, but little data on the transport is available to date. Methods: An analysis of all flights with the German Air Force's intensive care fixed-wing-aircraft carried out in the context of humanitarian aid missions since 2002 with a focus on intubated patients was done. Results: A total of 38 patients were transported. Two patients had to be intubated on or during transport. There were significant changes in the necessary positive end-expiratory pressure (PEEP) and the fraction of inspired oxygen. Circulatory parameters did not change. Discussion: Overall, there are no clinically relevant deteriorations due to secondary transport with corresponding air transfers. Due to the hypobaric hypoxic conditions on board of all aircrafts, intubation in clinically borderline patients should be performed electively on the ground before flight.

Fatigue and Ability to Concentrate in Flight Attendants During Ultra-Long-Range Flights.

Sammito, Stefan, David Cyrol, and Janina Post. Fatigue and ability to concentrate in flight attendants during ultra-long-range flights. High Alt Med Biol. 23:159-164, 2022. Background: Scientific studies on stresses and strains experienced by flight crews in the ultra-long-range (ULR) sector have focused on the group of pilots. Studies on cabin crews are rare. Methods: The subjective fatigue, concentration, and responsiveness of 16 flight attendants were examined during 3 flights (first and third flights were ULR flights) and related to the local time at the home airport. The flight route was Cologne/Bonn (Germany) to Canberra (Australia) (first flight), Tahiti (French Polynesia) (second flight), and back to Cologne/Bonn (third flight). Results: Overall, there was an increase in fatigue (first flight: +36.0% and third flight: +38.5%) as well as reduced responsiveness (-32.5% and -35.5%) and concentration (-30.0% and -33.5%) in the course of the ULR flights. A marked increase in fatigue occurred in particular during night hours measured against the local time at the home airport, especially at the beginning of the third flight. For all parameters, there was consistently no difference between the individual shift groups of flight attendants (p > 0.05). Conclusions: ULR flights cause cabin crew members to become increasingly fatigued due to the length of the flights despite appropriate rest opportunities. The available findings can help to prepare in the best possible way for necessary flight safety through appropriate planning of shift models, especially with regard to the potentially critical takeoff and landing stages. To this end, local times at the home airport must also be taken into account.

Analysis of European Air Medical Evacuation Flights of Coronavirus Disease 2019 Patients.

OBJECTIVE: As part of the humanitarian response to the coronavirus disease 2019 (COVID-19) pandemic, the German and French Armed Forces provided air transport for patients from overwhelmed regional hospitals in Italy and France. The objective of this study was to analyze the characteristics of the missions and the medical conditions of COVID-19 patients transported during an air medical evacuation on fixed wing aircraft in March and April 2020. METHOD: This was a retrospective analysis of transport records as well as other documents for 58 COVID-19 patients requiring artificial ventilation. RESULTS: The median age of the transported patients was 61.5 years, and 61% of them had preexisting medical conditions. They had been ventilated for a median of 5 days and experienced the first symptoms 18 days before transport. The patients flown out of France had less days of ventilation before flight, a lower end-tidal carbon dioxide level at the beginning of the flight, and a lower Charlson Comorbidity Index. There were also some differences between the ventilation and the flight level flown by the 2 air forces. CONCLUSION: The intensive care transport of ventilated COVID-19 patients requires highly qualified personnel and appropriate equipment and should be planned appropriately.

The characteristics and potential applications of structural lipid droplet proteins in plants.

Plant cytosolic lipid droplets are storage organelles that accumulate hydrophobic molecules. They are found in many tissues and their general structure includes an outer lipid monolayer with integral and associated proteins surrounding a hydrophobic core. Two distinct types can be distinguished, which we define here as oleosin-based lipid droplets (OLDs) and non-oleosin-based lipid droplets (NOLDs). OLDs are the best characterized lipid droplets in plants. They are primarily restricted to seeds and other germinative tissues, their surface is covered with oleosin-family proteins to maintain stability, they store triacylglycerols (TAGs) and they are used as a source of energy (and possibly signaling molecules) during the germination of seeds and pollen. Less is known about NOLDs. They are more abundant than OLDs and are distributed in many tissues, they accumulate not only TAGs but also other hydrophobic molecules such as natural rubber, and the structural proteins that stabilize them are unrelated to oleosins. In many species these proteins are members of the rubber elongation factor superfamily. NOLDs are not typically used for energy storage but instead accumulate hydrophobic compounds required for environmental interactions such as pathogen defense. There are many potential applications of NOLDs including the engineering of lipid production in plants and the generation of artificial oil bodies.

Down-regulation of small rubber particle protein expression affects integrity of rubber particles and rubber content in Taraxacum brevicorniculatum.

The biosynthesis of rubber is thought to take place on the surface of rubber particles in laticifers, highly specialized cells that are present in more than 40 plant families. The small rubber particle protein (SRPP) has been supposed to be involved in rubber biosynthesis, and recently five SRPPs (TbSRPP1-5) were identified in the rubber-producing dandelion species Taraxacum brevicorniculatum. Here, we demonstrate by immunogold labeling that TbSRPPs are localized to rubber particles, and that rubber particles mainly consist of TbSRPP3, 4 and 5 as shown by high-resolution two-dimensional gel electrophoresis and mass spectrometric analysis. We also carried out an RNA-interference approach in transgenic plants to address the function of TbSRPPs in rubber biosynthesis as well as rubber particle morphology and stability. TbSRPP-RNAi transgenic T. brevicorniculatum plants showed a 40-50% reduction in the dry rubber content, but neither the rubber weight average molecular mass nor the polydispersity of the rubber were affected. Although no phenotypical differences to wild-type particles could be observed in vivo, rubber particles from the TbSRPP-RNAi transgenic lines were less stable and tend to rapidly aggregate in expelling latex after wounding of laticifers. Our results prove that TbSRPPs are very crucial for rubber production in T. brevicorniculatum, probably by contributing to a most favourable and stable rubber particle architecture for efficient rubber biosynthesis and eventually storage.

Laticifer-specific cis-prenyltransferase silencing affects the rubber, triterpene, and inulin content of Taraxacum brevicorniculatum.

Certain Taraxacum species, such as Taraxacum koksaghyz and Taraxacum brevicorniculatum, produce large amounts of high-quality natural rubber in their latex, the milky cytoplasm of specialized cells known as laticifers. This high-molecular mass biopolymer consists mainly of poly(cis-1,4-isoprene) and is deposited in rubber particles by particle-bound enzymes that carry out the stereospecific condensation of isopentenyl diphosphate units. The polymer configuration suggests that the chain-elongating enzyme (rubber transferase; EC 2.5.1.20) is a cis-prenyltransferase (CPT). Here, we present a comprehensive analysis of transgenic T. brevicorniculatum plants in which the expression of three recently isolated CPTs known to be associated with rubber particles (TbCPT1 to -3) was heavily depleted by laticifer-specific RNA interference (RNAi). Analysis of the CPT-RNAi plants by nuclear magnetic resonance, size-exclusion chromatography, and gas chromatography-mass spectrometry indicated a significant reduction in rubber biosynthesis and a corresponding 50% increase in the levels of triterpenes and the main storage carbohydrate, inulin. Transmission electron microscopy revealed that the laticifers in CPT-RNAi plants contained fewer and smaller rubber particles than wild-type laticifers. We also observed lower activity of hydroxymethylglutaryl-coenzyme A reductase, the key enzyme in the mevalonate pathway, reflecting homeostatic control of the isopentenyl diphosphate pool. To our knowledge, this is the first in planta demonstration of latex-specific CPT activity in rubber biosynthesis.