Safety protocols, precautions, and countermeasures aboard the International Space Station (ISS) to prevent ocular injury.

The International Space Station (ISS) is a $100 billion epicenter of human activity in the vacuum of space, displaying mankind's collective endeavor to explore the cosmic frontier. Even within the marvels of technological sophistication aboard the ISS, the human eye remains a highly vulnerable structure. In the absence of multiple layers of protection and risk assessments, crewmembers would face a substantial increase in vulnerability to ocular injury. Aside from stringent preflight screening criteria for astronauts, the ISS is equipped with ophthalmic medications, environmental control and life support systems (e.g., humidity regulation, carbon dioxide removal, pressurized device regulators), and radiation protection to reduce ocular injury. Moreover, additional countermeasures are currently being developed to mitigate the effects of spaceflight-associated neuro-ocular syndrome (SANS) and lunar dust toxicity for the Artemis Program missions. The success of future endeavors hinges not only on continued technological innovation, but also respecting the intricate interplay between human physiology and the extraterrestrial environments. Establishing habitations on the Moon and Mars, as well as NASA's Gateway Program (humanity's first space station around the Moon), will introduce a new set of challenges, underscoring the necessity for continuous insights into ocular health in space. We discuss the safety protocols, precautions, and countermeasures implemented on the ISS to prevent ocular injury - an aspect often overshadowed by the grandeur of space exploration.

Efficacy of Gasserian Ganglion High-Voltage, Long-Duration Pulsed Radiofrequency Combined With Block on Acute/Subacute Zoster-Related Trigeminal Neuralgia.

Background: Trigeminal postherpetic neuralgia (TPHN) is a severe chronic pain that can lead to various socioeconomic consequences. Therefore, it is necessary to explore optimal treatment options for acute/subacute herpes zoster (HZ)-related trigeminal neuralgia and prevent the further development of TPHN. High-voltage, long-duration pulsed radiofrequency (HL-PRF) of the Gasserian ganglion is a new surgical intervention used to treat PHN. A ganglion block has been reported to possess anti-inflammatory effects and potential analgesic benefits. Methods: We included 83 patients with HZ-related acute/subacute trigeminal neuralgia admitted from January 1, 2021, to June 1, 2023, and received Gasserian ganglion HL-PRF combined with block. A 6-month follow-up was conducted, including Numerical Rating Scale (NRS) scores, Pittsburgh Sleep Quality Index (PSQI), the incidence of TPHN, the dosage of anticonvulsants and analgesics, efficacy, and adverse events. Results: All patients showed a significant decrease in postoperative NRS scores (p < 0.05). The NRS scores of the acute HZ group were consistently lower than those of the subacute HZ group at different time points (p < 0.01). The overall incidence of TPHN from the onset of HZ to 12 weeks is 21.68%. The incidence of TPHN in the acute phase group was 12.77%, significantly lower than the 33.33% in the subacute phase group (p=0.024). The effective rate was 74.7% in all patients, at 3 months after the treatment. The effective rate was 82.98% in the acute phase group and 63.89% in the subacute phase group, showing a statistically significant difference (p=0.047). The PSQI score of the acute group was consistently lower than that of the subacute group (p < 0.01). The dosage of analgesics and anticonvulsants used in the acute HZ group was lower than that in the subacute group (p < 0.01). All patients did not experience serious adverse reactions. Conclusions: Gasserian ganglion HL-PRF combined with block can be an effective and safe technique to relieve the pain of acute/subacute zoster-related trigeminal neuralgia and prevent the incidence of TPHN.

Computer simulation of low-power and long-duration bipolar radiofrequency ablation under various baseline impedances.

Compared to traditional unipolar radiofrequency ablation (RFA), bipolar RFA offers advantages such as more precise heat transfer and higher ablation efficiency. Clinically, myocardial baseline impedance (BI) is one of the important factors affecting the effectiveness of ablation. We aim at finding suitable ablation protocols and coping strategies by analyzing the ablation effects and myocardial impedance changes of bipolar RFA under different BIs. In this research, a three-dimensional local myocardial computer model was constructed for bipolar RFA simulation, and in vitro experimental data were used to validate accuracy. Four fixed low-power levels (20 W, 25 W, 30 W, and 35 W) and six myocardial BIs (91.02 Ω, 99.83 Ω, 111.03 Ω, 119.77 Ω, 130.03 Ω, and 135.45 Ω) were set as initial conditions, with an ablation duration of 120-s. In the context of low-power and long-duration (LPLD) ablation, the maximum TID (TIDM) decreased by 21-32 Ω, depending on the BI. In cases where steam pop did not occur, TIDM increased with the increase in power. For the same power, there was no significant difference in TIDM for the range of BIs. In cases where steam pop occurred, for every 1 Ω increase in BI, TIDM increased by 0.34-0.41 Ω. The simulation results also showed that using a higher power resulted in a smaller decrease in TIDM. This study provided appropriate ablation times and impedance decrease ranges for bipolar LPLD RFA. The combination of 25 W for 120-s offered optimal performance when considering effectiveness and safety simultaneously.

Comparative Analysis of Clinical Outcomes of High-power, Short-duration Ablation versus Low-power, Long-duration Ablation Strategy in Patients with Atrial Fibrillation: A Comprehensive Umbrella Review of Meta-analyses.

Atrial fibrillation (AF) affects around 33 million people worldwide, rendering it a common cardiac arrhythmia. Catheter ablation (CA) has evolved as a leading therapeutic intervention for symptomatic AF. This umbrella review systematically evaluates existing systematic reviews and meta-analyses to assess the safety, efficacy, and potential of high-power, short-duration (HPSD) ablation as an alternative therapy option for AF. A thorough exploration was undertaken across PubMed, the Cochrane Library, and Embase to identify pertinent studies for inclusion in this umbrella review. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) method was employed to assess the overall certainty of the evidence comprehensively, and the quality of the incorporated reviews was meticulously evaluated through use of the AMSTAR 2 tool, the Cochrane Collaboration tool, and the Newcastle-Ottawa scale. In this study, we initially identified 35 systematic reviews and meta-analyses, narrowing them down to a final selection of 11 studies, which collectively integrated data from 6 randomized controlled trials and 26 observational studies. For primary efficacy outcomes, the HPSD approach led to a non-significant decrease in the risk of atrial tachyarrhythmia recurrence (risk ratio [RR], 0.88; 95% confidence interval [CI], 0.70-1.12; I 2 = 90%; P = .31) and a significantly reduced risk of AF recurrence (RR, 0.53; 95% CI, 0.42-0.67; I 2 = 0%; P < .00001) compared to the low-power, long-duration (LPLD) approach. In terms of primary safety outcomes, the HPSD approach significantly reduced the risk of esophageal thermal injury (ETI) (RR, 0.71; 95% CI, 0.61-0.83; I 2 = 0%; P < .00001) and facilitated a non-significant decrease in the risk of other major complications (RR, 0.87; 95% CI, 0.73-1.03; I 2 = 0%; P = .10). In conclusion, HPSD therapy is safer and more effective than LPLD therapy, facilitating decreased AF recurrence rates along with reductions in ETI, total procedure duration, ablation number, ablation time, fluoroscopy time, and acute pulmonary vein reconnection.

[Pricking-cupping combined with auricular thumbtack needle for postherpetic neuralgia of qi stagnation and blood stasis on chest and waist: a randomized controlled trial].

OBJECTIVE: To observe the clinical effect of pricking-cupping combined with auricular thumbtack needle for postherpetic neuralgia (PHN) of qi stagnation and blood stasis on chest and waist. METHODS: A total of 98 patients with PHN of qi stagnation and blood stasis on chest and waist were randomized into an observation group (49 cases, 1 case was eliminated, 1 case dropped out) and a control group (49 cases, 1 case dropped out). In the observation group, treatment of pricking-cupping combined with auricular thumbtack needle was delivered, pricking and cupping were applied at Jiaji points (EX-B 2) at the related spinal segments corresponding to the pain sites and regional ashi points, once every other day, auricular thumbtack needle was applied at Xin (CO15), Shenmen (TF4), Neifenmi (CO18), Pizhixia (AT4), etc., once every 3 days. In the control group, pregabalin capsule was taken orally, 75 mg a time, twice a day. The treatment of 4 weeks was required in the two groups. Before and after treatment, the scores of TCM symptom, visual analogue scale (VAS), Pittsburgh sleep quality index (PSQI), self-rating depression scale (SDS) and self-rating anxiety scale (SAS) were observed, the serum levels of immunoglobulin G (IgG), interleukin-6 (IL-6), C-reactive protein (CRP) were detected, and the clinical efficacy and safety were evaluated in the two groups. RESULTS: After treatment, the item scores and total scores of TCM symptom, as well as the scores of VAS, PSQI, SDS and SAS were decreased compared with those before treatment (P<0.05); the item scores of pruritus degree, tactile sensitivity, skin numbness and total score of TCM symptom, as well as the scores of VAS, PSQI, SDS and SAS in the observation group were lower than those in the control group (P<0.05). After treatment, the serum levels of IgG were increased (P<0.05), while the serum levels of IL-6 and CRP were decreased (P<0.05) compared with those before treatment in the two groups; in the observation group, the serum level of IgG was higher (P<0.05), while the serum levels of IL-6 and CRP were lower (P<0.05) than those in the control group. The total effective rate was 95.7% (45/47) in the observation group, which was superior to 77.1% (37/48) in the control group (P<0.05). The incidence rate of adverse reaction was 6.4% (3/47) in the observation group, which was lower than 12.5% (6/48) in the control group (P<0.05). CONCLUSION: Pricking-cupping combined with auricular thumbtack needle can effectively relieve the clinical symptoms in patients with PHN of qi stagnation and blood stasis on chest and waist, reduce the pigmentation of herpes and improve itch or burning, numb sensations in the skin lesions, improve the sleep quality and relieve anxiety and depression.

Cardiovascular effects of long-duration space flight.

Introduction: Early studies exploring the physiological effects of space travel have indicated the body's capacity for reversible adaptation. However, the impact of long-duration spaceflight, exceeding 6 months, presents more intricate challenges. Effects on the Cardiovascular CV System: Extended exposure to microgravity and radiation profoundly affects the CV system. Notable phenomena include fluid shifts toward the head and modified arterial pressure. These changes disrupt blood pressure regulation and elevate cardiac output. Additionally, the loss of venous compression leads to a reduction in central venous pressure. Fluid and Plasma Volume Changes: The displacement of fluid from the vascular system to the interstitium, driven by baroreceptor stimulation, results in a 10%-15% decline in plasma volume. Cardiac Muscle and Hematocrit Variations: Intriguingly, despite potential increases in cardiac workload, cardiac muscle atrophy and perplexing variations in hematocrit levels have been observed. The mechanism underlying atrophy appears to involve a shift in protein synthesis from the endoplasmic reticulum to the mitochondria via mortalin-mediated mechanisms. Arrhythmias and QT Interval Prolongation: Instances of arrhythmias have been recurrently documented, although generally nonlethal, in both Russian and American space missions. Long-duration spaceflight has been associated with the prolongation of the QT interval, particularly in extended missions. Radiation Effects: Exposure of the heart to the proton and heavy ion radiation pervasive in deep space contributes to coronary artery degeneration, augmented aortic stiffness, and carotid intima thickening through collagen-mediated processes. Moreover, it accelerates the onset of atherosclerosis and triggers proinflammatory responses. Reentry and Postflight Challenges: Upon reentry, astronauts frequently experience orthostatic intolerance and altered sympathetic responses, which bear potential hazards in scenarios requiring rapid mobilization or evacuation. Conclusion: Consequently, careful monitoring of these cardiac risks is imperative for forthcoming missions. While early studies illuminate the adaptability of the body to space travel's challenges, the intricacies of long-duration missions and their effects on the CV system necessitate continued investigation and vigilance to ensure astronaut health and mission success.

Neurostimulation as a technology countermeasure for dry eye syndrome in astronauts.

Dry eye syndrome (DES) poses a significant challenge for astronauts during space missions, with reports indicating up to 30% of International Space Station (ISS) crew members. The microgravity environment of space alters fluid dynamics, affecting distribution of fluids on the surface of the eye as well as inducing cephalad fluid shifts that can alter tear drainage. Chronic and persistent DES not only impairs visual function, but also compromises the removal of debris, a heightened risk for corneal abrasions in the microgravity environment. Despite the availability of artificial tears on the ISS, the efficacy is challenged by altered fluid dynamics within the bottle and risks of contamination, thereby exacerbating the potential for corneal abrasions. In light of these challenges, there is a pressing need for innovative approaches to address DES in astronauts. Neurostimulation has emerged as a promising technology countermeasure for DES in spaceflight. By leveraging electrical signals to modulate neural function, neurostimulation offers a novel therapeutic avenue for managing DES symptoms. In this paper, we will explore the risk factors and current treatment modalities for DES, highlighting the limitations of existing approaches. Furthermore, we will delve into the novelty and potential of neurostimulation as a countermeasure for DES in future long-duration missions, including those to the Moon and Mars.

Dexmedetomidine Attenuates Inflammation in Elderly Patients Following Major Hepatobiliary and Pancreatic Surgery: A Randomized Clinical Trial.

Background: Dexmedetomidine (Dex) may have anti-inflammatory properties and potentially reduce the incidence of postoperative organ injury. Objective: To investigate whether Dex protects pulmonary and renal function via its anti-inflammatory effects in elderly patients undergoing prolonged major hepatobiliary and pancreatic surgery. Design and Setting: Between October 2019 and December 2020, this randomized controlled trial was carried out at a tertiary hospital in Chongqing, China. Patients: 86 patients aged 60-75 who underwent long-duration (> 4 hrs) hepatobiliary and pancreatic surgery without significant comorbidities were enrolled and randomly assigned into two groups at a 1:1 ratio. Interventions: Patients were given either Dex or an equivalent volume of 0.9% saline (Placebo) with a loading dose of 1 µg kg-1 for 10 min, followed by 0.5 µg kg-1 hr-1 for maintenance until the end of surgery. Main Outcome Measures: The changes in serum concentrations of interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) were primary outcomes. Results: At one hour postoperatively, serum IL-6 displayed a nine-fold increase (P<0.05) in the Placebo group. Administration of Dex decreased IL-6 to 278.09 ± 45.43 pg/mL (95% CI: 187.75 to 368.43) compared to the Placebo group (P=0.019; 432.16 ± 45.43 pg/mL, 95% CI: 341.82 to 522.50). However, no significant differences in TNF-α were observed between the two groups. The incidence of postoperative acute kidney injury was twice as high in the Placebo group (9.30%) compared to the Dex group (4.65%), and the incidence of postoperative acute lung injury was 23.26% in the Dex group, lower than that in the Placebo group (30.23%), although there was no statistical significance between the two groups. Conclusion: Dex administration in elderly patients undergoing major hepatobiliary and pancreatic surgery reduces inflammation and potentially protects kidneys and lungs. Registration: Chinese Clinical Trials Registry, identifier: ChiCTR1900024162, on 28 June 2019.

A Study on the Critical Saturation Response Characteristics of Simple and Sandwich Cylindrical Shells under Long-Duration Blast Loading.

Experimental research and numerical simulations of the structural response to shock waves with pulse durations of hundreds of milliseconds, or even seconds, are extremely challenging. This paper takes typical single-layer and sandwich cylindrical shells as the research objects. The response rules of cylindrical shells under long-duration blast loadings were studied. The results show that when the pulse duration is greater than or equal to 4~5 times the first-order period of the structure, the maximum response of the structure tends to be consistent, that is, the maximum response of the cylindrical shells with different vibration shapes shows a saturation effect as the pulse duration increases. This study established the relationship between the saturation loading time and the inherent characteristics of the structure. It was found that the saturation effect was applicable under the following conditions, including different load waveforms, elastic-plastic deformation of the structure, and the loading object being a sandwich shell. This will help transform the long-duration explosion wave problem into a finite pulse-duration shock wave problem that can be realized by both experiments and numerical simulations.

Markedly Delayed Presentation of a Psychotic Disorder 10 Years After the First Onset of Symptoms.

Schizophrenia affects 1% of the population, causing chronic debilitating symptoms with largely unknown causes. Structural brain changes and neurochemical alterations are believed to contribute to its etiology. Delayed treatment initiation is a major concern. This case involves a male patient with a decade-long history of psychosis, experiencing isolation, agoraphobia, and paranoid delusions. His situation deteriorated to the point where he lived in a self-imposed physically constraining environment for a year, leading to muscle atrophy and deteriorating health. Delayed help-seeking was driven by insurance concerns, despite prior academic success. Following extensive evaluation, he received the diagnosis of schizophrenia (first episode, severe), requiring multidisciplinary treatment, including medication adjustments and therapy. This case serves as a poignant illustration of a missed opportunity for early intervention, with treatment initiated only after symptoms became severe. Research indicates that early intervention in schizophrenia is crucial, typically leading to improved outcomes, emphasizing its critical importance.

Robust capital cost optimization of generation and multitimescale storage requirements for a 100% renewable Australian electricity grid.

Transitioning from a fossil-fuel-dependent economy to one based on renewable energy requires significant investment and technological advancement. While wind and solar technologies provide lower cost electricity, enhanced energy storage and transmission infrastructure come at a cost for managing renewable intermittency. Energy storage systems vary in characteristics and costs, and future grids will incorporate multiple technologies, yet the optimal combination of storage technologies and the role of interconnectors in alleviating storage needs are not widely explored. This study focuses on optimal generation-storage capacity requirements to elucidate associated investments. We propose a multitimescale storage solution consisting of three storage categories and an interconnector between Australia's eastern and western grids. Subsequently, through an extensive sensitivity analysis, we investigate the impact of specific storage technologies and cost variations. Our findings demonstrate that the proposed interconnector offers a cost-effective solution, reducing generation and storage power capacity needs by 6 and 14%, respectively, resulting in 4% savings on overall investment costs. Moreover, the study's sensitivity analysis reveals that wind generation provides 50-70% of the energy demand for the least-cost solution. Despite storage inefficiencies, long-duration storage would need to be deployed to support power capacity for 2-4 days, representing 15-40% of peak demand, depending on future technology costs. Subsequently, achieving a fully renewable electricity sector in Australia requires a significant expansion of generation and storage infrastructure, with a 13-fold increase in storage power capacity and a 40-fold increase in storage energy capacity compared to existing levels.

The impact of energy storage on the reliability of wind and solar power in New England.

In this study, the potential of wind and solar power to reliably meet the electricity demand of New England is evaluated, as well as the role of energy storage in improving the reliability of the region's renewable energy system. Using 44 years of hourly weather data from 1980 to 2023 obtained from the NASA MERRA-2 reanalysis product, the variability of these renewable resources and their impact on the region's electricity supply and demand is investigated. With varying mixes of wind and solar resources and sufficient resources capacity to generate electricity equal to annual demand, we find that a wind-dominant system can meet approximately 73% of the region's hourly electricity demand, whereas a solar-dominant system can only meet about 69%. However, incorporating 12 h of energy storage enhances the overall reliability of a wind-dominant system to 86%. In comparison, incorporating the same amount of energy storage in a solar-dominant system results in an overall reliability of approximately 87%. Ultimately, our analysis shows that achieving 100% reliability in meeting the annual electricity demand of New England requires addressing the mismatch between electricity demand and resource availability in terms of both location and time. This can be achieved through the integration of significant amounts of energy storage and/or wind and solar resources installations capable of generating electricity that exceeds peak demand by at least 3 times.

Detection of retinal dysfunction induced by HCN channel inhibitors using multistep light stimulus and long-duration light stimulus ERG in rats.

Ivabradine, a hyperpolarization-activated cyclic nucleotide-gated (HCN) channel inhibitor, has been reported to induce photosensitivity-related visual disturbances such as phosphene in humans. Ivabradine-induced visual disturbances are caused by inhibition of HCN channels in the retina, and the mechanisms have been verified using HCN channel knockout mice and electroretinography (ERG). However, in rats, classical ERG using single flash light stimulus with standard analyses of waveform amplitude and latency has not revealed abnormal retinal function after administration of ivabradine. To verify whether retinal dysfunction after ivabradine administration was detectable in rats, we performed ERG using multistep flash light stimulation at the time when plasma concentration of ivabradine was high. Furthermore, the mechanism of the change in the waveform that appeared after the b-wave was investigated. Ivabradine and cilobradine, a selective HCN channel inhibitor, were administered subcutaneously to rats at 4-40 mg/kg as a single dose, and flash or long-duration ERG recordings at each light stimulus luminance were conducted 1.5 h after administration. Plasma and retinal concentrations of both compounds were measured immediately after the ERG recordings. In the flash ERG, prolongation of a- and/or b-wave latencies were detected at each light stimulus, and dose-dependent waveform changes after the b-wave were recorded at the specific light stimulus luminance for both compounds. These ERG changes increased in response to increasing plasma and retinal concentrations for both ivabradine and cilobradine. In the long-duration light stimulus ERG, a change in the waveform of the b-wave trough and attenuation of the c-wave were recorded, suggesting that the feedback control in the photoreceptor cells may be inhibited. This study revealed that the retinal dysfunction by HCN channel inhibitors in rats can be detected by multistep light stimulus ERG. Additionally, we identified that the inhibition of feedback current and the sustained responses in the photoreceptor cells cause the retinal dysfunction of HCN channel inhibitors in rats.

Bipolar, high-voltage, long-duration pulsed radiofrequency ablation of the Gasserian ganglion for the treatment of trigeminal neuralgia in a patient with a cardiac implantable electronic device: illustrative case.

BACKGROUND: One of the common methods of treating trigeminal neuralgia (TN) nowadays is radiofrequency therapy. However, it has serious limitations in patients with a cardiac pacemaker because of electromagnetic interference. Therefore, it is crucial to select optimal radiofrequency ablation parameters to make this procedure safe with favorable outcomes for such patients. OBSERVATIONS: In this study, the authors present a case of a 70-year-old man with a history of cardiac pacemaker dependency and previous microvascular decompression with complaints of severe, constant facial pain. After reprogramming the cardiac implantable electronic device (CIED), the authors performed bipolar, high-voltage, long-duration pulsed radiofrequency therapy (PRFT) of the Gasserian ganglion under electrocardiography and pulse rate control in the pre-, intra-, and postoperative periods. There were no cardiovascular or neurological complications after PRFT. The patient reported relief of pain after the procedure, and at the 9-month follow-up, he was pain-free. LESSONS: This clinical case demonstrates that the use of bipolar, high-voltage PRFT for TN treatment in patients with a CIED can be safe and effective, provided that the rules and pacemaker instructions are followed. It is necessary to use ablative treatment with caution and to guide the patient in collaboration with a cardiac surgeon and an anesthesiologist resuscitator.

Team Dynamics and Collaborative Problem-Solving for Lunar Construction: Lessons From Complex Construction Scenarios on Earth.

OBJECTIVE: This paper surveys the existing literature surrounding problem-solving and team dynamics in complex and unpredictable scenarios, and evaluates the applicability of studying Earth-based construction teams to identify training needs for Lunar construction crews. BACKGROUND: Lunar and other space exploration construction crews will work in extreme environments and face unpredictable challenges, necessitating real-time problem-solving to address unexpected contingencies. This work will require coordination with Mission Control and autonomous assistants, so crew training must account for multi-agent, distributed teamwork. METHOD: A narrative literature review identified processes, attributes, and skills necessary for the success of Lunar construction teams. We summarized relevant frameworks and synthesized collective findings into over-arching trends and remaining research gaps. RESULTS: While significant literature exists surrounding team performance, very little systematic inquiry has been done with a focus on Lunar construction crews and operations, particularly with respect to dynamic problem-solving and team-based decision-making. Established and standardized metrics for evaluating team performance are lacking, resulting in significant variation in reported outcomes between studies. CONCLUSION: Lunar and other space exploration construction teams will need training that focuses on developing the right approach to team-based problem-solving, rather than on preparing response execution for known contingencies. An investigation of successful Earth-based construction crews may facilitate the development of relevant metrics for training future Lunar construction crews. APPLICATION: Metrics and team training protocols developed for future Lunar construction teams may be adaptable and applicable to a wide range of extreme teams facing uncertain challenges, such as aircrews, surgical teams, first responders, and construction crews.

Thermoelectric Generator Through Dual-Direction Thermal Regulation by Thermal Diodes for Waste Heat Harvesting.

Thermal energy harvesting provides an opportunity for multi-node systems to achieve self-power autonomy. Thermoelectric generators (TEGs), either by thermocouple arrangement with higher-aspect-ratios or thermoelectric films overlay, are limited by the small temperature difference and its short-duration (less than dozens of minutes), hindering the harvesting efficiency. Here, by introducing thermal diodes with dual-direction thermal regulation ability to optimize the heat flux path, the proposed TEGs exhibit enhanced power-supply capability with unprecedented long-duration (more than hours). In contrast with conventional TEGs with fixed-leg dimensions enabled single output, these compact-TEGs can supply up to fourteen output-channels for selection, the produced power ranges from 1.11 to 921.99 µW, open circuit voltage ranges from 8.07 to 51.32 mV, when the natural temperature difference is 53.84 °C. Compared to the most recent TEGs, the proposed TEGs in this study indicate higher power (more than hundreds times) and much longer output duration (2.4-120 times) in a compact manner.

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.

Precisional modulation of translaminar pressure gradients for ophthalmic diseases.

The translaminar pressure gradient (TLPG) refers to two forces at the lamina cribosa of the optic nerve: the anteriorly acting intracranial pressure (ICP), and posteriorly-acting intraocular pressure (IOP). It has been proposed that controlling the translaminar pressure gradient at regular intervals may preserve the optic nerve and slow the course of glaucoma. The precisional modulation of this TLPG is a recently introduced concept that may play a role in the treatment of ophthalmic diseases such as glaucoma. In this manuscript, we review the applications of pressurized goggles on ophthalmic diseases. We also elaborate upon current investigations in modulation of the TLPG including goggles and the multi-pressure dial goggle. We discuss future research directions for ophthalmic diseases including spaceflight associated neuro-ocular syndrome (SANS), a large physiological barrier to future long-duration spaceflight.

Power tether for long duration multi-copter flight.

The possibilities and promises of unmanned aerial vehicles (UAVs) for smart agriculture, 5G cellular integration, package delivery, and persistent surveillance are but a few of the active drivers for advancing UAV technology and systems. The UAVs' dependence on battery power represents a key limitation for practical deployment. As every remote pilot understands, even a modest research payload can limit a UAV's endurance to under 20 min. When horizontal maneuverability is not required, a power tether from the ground can provide near infinite flight time. Commercial tethers exist but can be prohibitively expensive or underpowered for research payloads. This paper describes the detailed design, construction, and operation of a relatively inexpensive open-source alternative. The designed and prototyped tether system delivers 1 kW of power at the tether base which, on an efficient UAV, corresponds to a payload of approximately 4.75 kg. We discuss the tradeoffs, design choices, best practices, and customization options, and provide empirical data for characterizing the power-payload relationship. The power and payload are scalable thanks to the modular design and the tools presented in this paper. The very low cost compared to commercial heavy-lift tether systems and the open-source design enable reproducibility and widespread use for supporting research, development, and emerging services/applications.