A versatile sample-delivery system for X-ray photoelectron spectroscopy of in-flight aerosols and free nanoparticles at MAX IV Laboratory.

Aerosol science is of utmost importance for both climate and public health research, and in recent years X-ray techniques have proven effective tools for aerosol-particle characterization. To date, such methods have often involved the study of particles collected onto a substrate, but a high photon flux may cause radiation damage to such deposited particles and volatile components can potentially react with the surrounding environment after sampling. These and many other factors make studies on collected aerosol particles challenging. Therefore, a new aerosol sample-delivery system dedicated to X-ray photoelectron spectroscopy studies of aerosol particles and gas molecules in-flight has been developed at the MAX IV Laboratory. The aerosol particles are brought from atmospheric pressure to vacuum in a continuous flow, ensuring that the sample is constantly renewed, thus avoiding radiation damage, and allowing measurements on the true unsupported aerosol. At the same time, available gas molecules can be used for energy calibration and to study gas-particle partitioning. The design features of the aerosol sample-delivery system and important information on the operation procedures are described in detail here. Furthermore, to demonstrate the experimental range of the aerosol sample-delivery system, results from aerosol particles of different shape, size and composition are presented, including inorganic atmospheric aerosols, secondary organic aerosols and engineered nanoparticles.

Production and separation of positron emitters for hadron therapy at FRS-Cave M.

The FRagment Separator FRS at GSI is a versatile spectrometer and separator for experiments with relativistic in-flight separated short-lived exotic beams. One branch of the FRS is connected to the target hall where the bio-medical cave (Cave M) is located. Recently a joint activity between the experimental groups of the FRS and the biophysics at the GSI and Department of physics at LMU was started to perform biomedical experiments relevant for hadron therapy with positron emitting carbon and oxygen beams. This paper presents the new ion-optical mode and commissioning results of the FRS-Cave M branch where positron emitting 15O-ions were provided to the medical cave for the first time. An overall conversion efficiency of 2.9±0.2×10-4 15O fragments per primary 16O ion accelerated in the synchrotron SIS18 was reached.

Genomic Evidence of In-Flight SARS-CoV-2 Transmission, India to Australia, April 2021.

Epidemiologic and genomic investigation of SARS-CoV-2 infections associated with 2 repatriation flights from India to Australia in April 2021 indicated that 4 passengers transmitted SARS-CoV-2 to >11 other passengers. Results suggest transmission despite mandatory mask use and predeparture testing. For subsequent flights, predeparture quarantine and expanded predeparture testing were implemented.

In-Flight Alignment of Integrated SINS/GPS/Polarization/Geomagnetic Navigation System Based on Federal UKF.

As a common integrated navigation system, the strapdown inertial navigation system (SINS)/global positioning system (GPS) can estimate velocity and position errors well. Many auxiliary attitude measurement systems can be used to improve the accuracy of attitude angle errors. In this paper, the in-flight alignment problem of the integrated SINS/GPS/Polarization/Geomagnetic navigation system is discussed. Firstly, the SINS/Geomagnetic subsystem is constructed to improve the estimation accuracy of horizontal attitude angles. Secondly, the polarization sensor is used to improve the estimation accuracy of heading angle. Then, a federal unscented Kalman filter (FUKF) with non-reset structure is applied to fuse the navigation data. Finally, simulation results for the integrated navigation system are provided based on experimental data. It can be shown that the proposed approach can improve not only the speed and position, but also the attitude error effectively.

Genomic Evidence of In-Flight Transmission of SARS-CoV-2 Despite Predeparture Testing.

Since the first wave of coronavirus disease in March 2020, citizens and permanent residents returning to New Zealand have been required to undergo managed isolation and quarantine (MIQ) for 14 days and mandatory testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As of October 20, 2020, of 62,698 arrivals, testing of persons in MIQ had identified 215 cases of SARS-CoV-2 infection. Among 86 passengers on a flight from Dubai, United Arab Emirates, that arrived in New Zealand on September 29, test results were positive for 7 persons in MIQ. These passengers originated from 5 different countries before a layover in Dubai; 5 had negative predeparture SARS-CoV-2 test results. To assess possible points of infection, we analyzed information about their journeys, disease progression, and virus genomic data. All 7 SARS-CoV-2 genomes were genetically identical, except for a single mutation in 1 sample. Despite predeparture testing, multiple instances of in-flight SARS-CoV-2 transmission are likely.

Cabin air quality on non-smoking commercial flights: A review of published data on airborne pollutants.

We reviewed 47 documents published 1967-2019 that reported measurements of volatile organic compounds (VOCs) on commercial aircraft. We compared the measurements with the air quality standards and guidelines for aircraft cabins and in some cases buildings. Average levels of VOCs for which limits exist were lower than the permissible levels except for benzene with average concentration at 5.9 ± 5.5 µg/m3 . Toluene, benzene, ethylbenzene, formaldehyde, acetaldehyde, limonene, nonanal, hexanal, decanal, octanal, acetic acid, acetone, ethanol, butanal, acrolein, isoprene and menthol were the most frequently measured compounds. The concentrations of semi-volatile organic compounds (SVOCs) and other contaminants did not exceed standards and guidelines in buildings except for the average NO2 concentration at 12 ppb. Although the focus was on VOCs, we also retrieved the data on other parameters characterizing cabin environment. Ozone concentration averaged 38 ppb below the upper limit recommended for aircraft. The outdoor air supply rate ranged from 1.7 to 39.5 L/s per person and averaged 6.0 ± 0.8 L/s/p (median 5.8 L/s/p), higher than the minimum level recommended for commercial aircraft. Carbon dioxide concentration averaged 1315 ± 232 ppm, lower than what is permitted in aircraft and close to what is permitted in buildings. Measured temperatures averaged 23.5 ± 0.8°C and were generally within the ranges recommended for avoiding thermal discomfort. Relative humidity averaged 16% ± 5%, lower than what is recommended in buildings.

The global incidence of in-flight medical emergencies: A systematic review and meta-analysis of approximately 1.5 billion airline passengers.

BACKGROUND: Medical emergencies during short- or long-haul commercial airline flights have become more commonplace due to the aviation industry's contemporary growth, the popularization of commercial flights, and an increased aging of air travelers with significant comorbidities. However, the precise incidence of onboard medical events on commercial airlines and the most common medical conditions is unclear. METHODS: In this systematic review and meta-analysis, we explored the incidence of in-flight medical emergencies among airline passengers and estimated the incidence rate by physiological body system, or organ class/syndrome for emergencies that may be associated with different body systems. We limited our search to cohort studies published between 1945 to October 31, 2020 in MEDLINE, Embase, Cochrane Library and official reports from the Federal Aviation Administration/International Air Transport Association, regardless of the language of publication. Only studies that evaluated the overall frequency of onboard medical events on commercial air carriers (in which they also presented the total number of annual revenue passengers) and the frequency of events by physiological body systems or organ class/syndrome were included. We excluded case reports and case series, systematic or narrative reviews, and studies addressing specific health-related conditions. Two independent investigators performed first- and second-phase study screening, abstracted data, and appraised risk of bias. We rated the certainty of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Using a quality effect model, we meta-analyzed data associated with the incidence of in-flight medical emergencies, all-cause fatality, incidence of medical events by medical condition category, frequency of en-route diversion, presence of medical personnel on board, and the use of an automatic external defibrillator. We also extracted data regarding the cost of flight diversion. RESULTS: Of 18 individual studies with approximately 1.5 billion passengers, 11 reported the overall incidence of in-flight medical emergencies. Low certainty of evidence suggested that the global incidence of in-flight medical emergencies was 18.2 events per million passengers (95% CI 0.5 to 53.4 per million; I2 = 100%, P < 0.001, very low certainty), and an all-cause mortality rate was 0.21 per million passengers (95% CI 0 to 0.76 per million; I2 = 99%, P < 0.001, low certainty). The four most common categories of medical conditions or syndromes during flight were syncope, gastrointestinal events, respiratory and neurological diagnostic groups. The diversion rate was 11.1 per 100,000 flights (95% CI 5.9 to17.6 per 100,000 flights; I2 = 97%, P < 0.001), with an average cost ranging from $15,000 to $893,000 per unplanned emergency landing across studies which examined this outcome. CONCLUSIONS: In-flight medical events on commercial travels are extremely low with a corresponding very low in-flight mortality rate. Associated costs derived from en-route diversion might significantly influence airlines' budgetary equilibrium. Novel and modern standardized reporting systems or platforms should be internationally provided and enforced by health and aviation authorities to obtain higher quality patient-passengers datasets. Onboard volunteer medical providers must be aware of everyday life-threatening events during commercial flights and should consider the establishment of a connection between the aircraft and ground-based medical advisory services while assisting in-flight medical events.

In-Flight Tests of Intruder Detection Vision System.

In the near future, the integration of manned and unmanned aerial vehicles into the common airspace will proceed. The changes taking place mean that the safety of light aircraft, ultralight aircraft and unmanned air vehicles (UAV) will become an increasing problem. The IDAAS project (Intruder Detection And collision Avoidance System) meets the new challenges as it aims to produce technically advanced detection and collision avoidance systems for light and unmanned aerial vehicles. The work discusses selected elements of research and practical tests of the intruder detection vision system, which is part the of IDAAS project. At the outset, the current formal requirements related to the necessity of installing anticollision systems on aircraft are presented. The concept of the IDAAS system and the structure of algorithms related to image processing are also discussed. The main part of the work presents the methodology developed for the needs of dedicated flight tests, its implementation and the results obtained. The initial tests of the IDAAS system carried out on an ultralight aircraft generally indicate the possibility of the effective detection of intruders in the airspace with the use of vision methods, although they also indicated the existence of conditions in which this detection may prove difficult or even impossible.

"Is there a doctor on board?": willingness and confidence of physicians in the Kingdom of Saudi Arabia in assisting with in-flight medical emergencies.

BACKGROUND: In-flight medical emergencies (IMEs) are common, and for a traveling physician, it is very likely to encounter such a condition. Data discussing this issue are limited. Thus, this study aimed to evaluate the willingness and confidence of physicians in the Kingdom of Saudi Arabia (KSA) in responding to IMEs. As well as, to assess the associated sociodemographic, occupational, and travel-related factors, and their previous experience with such events. METHODS: This cross-sectional, online-based, study was conducted among all physicians in KSA during January 2021. The self-administered questionnaire included questions on sociodemographic, occupational, travel profiles, willingness and confidence towards IMEs. Chi-Squared or Fisher's Exact test were used for bivariate analysis followed by the multivariable binary logistic regression analysis. RESULTS: A total of 4558 physicians participated in the study. About one-third of participants reported one or more IME incidents, and the vast majority of them provided assistance. Cardiovascular diseases were the most common IMEs. About half of the participating physicians are concerned about the medico-legal consequences of providing assistance with such a condition. Among all specialties, emergency physicians reported the highest willingness and confidence toward IMEs. Predictors for a physician's willingness to assist in IMEs were being male, having been involved in a previous IME situation, attended life support and IME courses, frequent traveling, and practicing medicine in the Central region of Saudi Arabia. CONCLUSION: Findings from the current study stressed the need for establishing standardized guidelines about the roles of healthcare workers and the legal consequences of providing medical assessment in IMEs. Moreover, training programs on IMEs to all physicians, especially those who deal with a variety of cases during their practice such as internal medicine and family medicine are also suggested.

Moral Dilemmas of Nurses and Paramedics During In-Flight Medical Emergencies on Commercial Airlines.

During commercial flights, in-flight medical emergencies may lead the cabin crew to request assistance from qualified health care professionals among the passengers. Although a physician's function and role are well known and virtually universal globally, the role, education, and scope of practice of nurses and paramedics varies significantly. This article analyzes the possible dilemmas that medical professionals other than physicians who assist during in-flight medical emergencies may face and presents recommendations for aviation authorities. There is an identified need for universal cross-border regulations and an awareness of legal and ethical boundaries for medical responders other than physicians on board commercial international aircraft.

Flight-Associated Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 Corroborated by Whole-Genome Sequencing.

To investigate potential transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during a domestic flight within Australia, we performed epidemiologic analyses with whole-genome sequencing. Eleven passengers with PCR-confirmed SARS-CoV-2 infection and symptom onset within 48 hours of the flight were considered infectious during travel; 9 had recently disembarked from a cruise ship with a retrospectively identified SARS-CoV-2 outbreak. The virus strain of those on the cruise and the flight was linked (A2-RP) and had not been previously identified in Australia. For 11 passengers, none of whom had traveled on the cruise ship, PCR-confirmed SARS-CoV-2 illness developed between 48 hours and 14 days after the flight. Eight cases were considered flight associated with the distinct SARS-CoV-2 A2-RP strain; the remaining 3 cases (1 with A2-RP) were possibly flight associated. All 11 passengers had been in the same cabin with symptomatic persons who had culture-positive A2-RP virus strain. This investigation provides evidence of flight-associated SARS-CoV-2 transmission.

A large national outbreak of COVID-19 linked to air travel, Ireland, summer 2020.

An outbreak of 59 cases of coronavirus disease (COVID-19) originated with 13 cases linked by a 7 h, 17% occupancy flight into Ireland, summer 2020. The flight-associated attack rate was 9.8-17.8%. Spread to 46 non-flight cases occurred country-wide. Asymptomatic/pre-symptomatic transmission in-flight from a point source is implicated by 99% homology across the virus genome in five cases travelling from three different continents. Restriction of movement on arrival and robust contact tracing can limit propagation post-flight.

A New In-Flight Alignment Method with an Application to the Low-Cost SINS/GPS Integrated Navigation System.

The optimization-based alignment (OBA) methods, which are implemented by the optimal attitude estimation using vector observations-also called double-vectors-have proven to be effective at solving the in-flight alignment (IFA) problem. However, the traditional OBA methods are not applicable for the low-cost strap-down inertial navigation system (SINS) since the error of double-vectors will be accumulated over time due to the substantial drift of micro-electronic- mechanical system (MEMS) gyroscope. Moreover, the existing optimal estimation method is subject to a large computation burden, which results in a low alignment speed. To address these issues, in this article we propose a new fast IFA method based on modified double-vectors construction and the gradient descent method. To be specific, the modified construction method is implemented by reducing the integration interval and identifying the gyroscope bias during the construction procedure, which improves the accuracy of double-vectors and IFA; the gradient descent scheme is adopted to estimate the optimal attitude of alignment without complex matrix operation, which results in the improvement of alignment speed. The effect of different sizes of mini-batch on the performance of the gradient descent method is also discussed. Extensive simulations and vehicle experiments demonstrate that the proposed method has better accuracy and faster alignment speed than the related traditional methods for the low-cost SINS/global positioning system (GPS) integrated navigation system.

Established and empirically derived landbird focal species lists correlate with vegetation and avian metrics.

Surrogate species are commonly used in conservation science due to the fact that it is not feasible to measure and manage each component of biodiversity independently; yet, there is much debate about their efficacy. We use long-term monitoring data from six national park units in northern California and southern Oregon to test the focal species approach, wherein a suite of species is selected whose habitat requirements collectively encompass those of co-occurring species. Specifically, we examine how well existing Partners in Flight (PIF) habitat-based focal species lists and empirically derived focal species lists represent vegetation and three avian assemblages of interest: the entire assemblage, species of concern, and common species in steep decline. Existing PIF focal species lists were significantly correlated with the three alternative matrices of avian assemblages and vegetation, but not all parks and alternate matrices performed with equal correlative strength and/or significance. For example, existing PIF focal species lists were significantly correlated to the entire assemblage at five of the six parks and had ecologically meaningful correlations (>0.70) at four. However, PIF focal species list correlations with park specific species of concern and common species in steep declined varied widely, with correlations between 0.040-0.943 and 0.210-0.556, respectively. Averaged across park units the empirical focal species lists developed to represent both vegetation metrics and species of concern improved correlation with all alternative matrices of avian assemblages and vegetation metrics. We found that the focal species approach generally represented the entire avian community, but did not adequately represent suites of species of concern or common species in decline. Empirical testing is a critical step in validating or refining suites of focal species at management relevant scales, and in some instances, a more refined focal species list may increase overall utility of the surrogate species approach.

Light-In-Flight Imaging by a Silicon Image Sensor: Toward the Theoretical Highest Frame Rate.

Light in flight was captured by a single shot of a newly developed backside-illuminated multi-collection-gate image sensor at a frame interval of 10 ns without high-speed gating devices such as a streak camera or post data processes. This paper reports the achievement and further evolution of the image sensor toward the theoretical temporal resolution limit of 11.1 ps derived by the authors. The theoretical analysis revealed the conditions to minimize the temporal resolution. Simulations show that the image sensor designed following the specified conditions and fabricated by existing technology will achieve a frame interval of 50 ps. The sensor, 200 times faster than our latest sensor will innovate advanced analytical apparatuses using time-of-flight or lifetime measurements, such as imaging TOF-MS, FLIM, pulse neutron tomography, PET, LIDAR, and more, beyond these known applications.

Prediction of particle deposition around the cabin air supply nozzles of commercial airplanes using measured in-cabin particle emission rates.

Enhanced soiling on the surfaces around air supply nozzles due to particle deposition is frequently observed in commercial airliners. The problem is worsened by severe outdoor air pollution and flight delays in China. The particles in an aircraft cabin originate from both outdoor and in-cabin sources. This study conducted measurements on multiple commercial flights to obtain particle emission rates from in-cabin sources. Additional experiments on a retired MD-82 airplane provided justification of the in-flight measurements. The in-cabin sources emitted more particles during boarding/deplaning than during meal servicing and sitting. The average PM2.5 emission rates were 7.2, 2.6, 1.9, and 1.8 (µg/min per person), respectively, during the boarding/deplaning, sitting on the ground, sitting in the air, and meal servicing. The corresponding PM10 emission rates were 15.4, 6.1, 5.3, and 5.4 (µg/min per person), respectively, for these four periods. The average particle emission rate from in-cabin sources varied seasonally and was the highest in winter. With the measured data, this investigation used a CFD model to predict the accumulation of particles deposited around the nozzles of an airplane, taking into account the flight routes and the outdoor particle concentrations at the airports where the airplanes were parked. For the most polluted airplane in China, the dirty spots/areas around the nozzles inside the airplane became visible after 6 months. The method proposed in this study can be used for any commercial airplane to predict the accumulation of particles deposited around the air supply nozzles.

Routes of transmission of influenza A H1N1, SARS CoV, and norovirus in air cabin: Comparative analyses.

Identifying the exact transmission route(s) of infectious diseases in indoor environments is a crucial step in developing effective intervention strategies. In this study, we proposed a comparative analysis approach and built a model to simulate outbreaks of 3 different in-flight infections in a similar cabin environment, that is, influenza A H1N1, severe acute respiratory syndrome (SARS) coronavirus (CoV), and norovirus. The simulation results seemed to suggest that the close contact route was probably the most significant route (contributes 70%, 95% confidence interval [CI]: 67%-72%) in the in-flight transmission of influenza A H1N1 transmission; as a result, passengers within 2 rows of the index case had a significantly higher infection risk than others in the outbreak (relative risk [RR]: 13.4, 95% CI: 1.5-121.2, P = .019). For SARS CoV, the airborne, close contact, and fomite routes contributed 21% (95% CI: 19%-23%), 29% (95% CI: 27%-31%), and 50% (95% CI: 48%-53%), respectively. For norovirus, the simulation results suggested that the fomite route played the dominant role (contributes 85%, 95% CI: 83%-87%) in most cases; as a result, passengers in aisle seats had a significantly higher infection risk than others (RR: 9.5, 95% CI: 1.2-77.4, P = .022). This work highlighted a method for using observed outbreak data to analyze the roles of different infection transmission routes.

Contact tracing for influenza A(H1N1)pdm09 virus-infected passenger on international flight.

In April 2009, influenza A(H1N1)pdm09 virus infection was confirmed in a person who had been symptomatic while traveling on a commercial flight from Mexico to the United Kingdom. Retrospective public health investigation and contact tracing led to the identification of 8 additional confirmed cases among passengers and community contacts of passengers.

Wastewater sequencing as a powerful tool to reveal SARS-CoV-2 variant introduction and spread in French Guiana, South America.

The origin of introduction of a new pathogen in a country, the evolutionary dynamics of an epidemic within a country, and the role of cross-border areas on pathogen dynamics remain complex to disentangle and are often poorly understood. For instance, cross-border areas represent the ideal location for the sharing of viral variants between countries, with international air travel, land travel and waterways playing an important role in the cross-border spread of infectious diseases. Unfortunately, monitoring the point of entry and the evolutionary dynamics of viruses in space and time within local populations remain challenging. Here we tested the efficiency of wastewater-based epidemiology and genotyping in monitoring Covid-19 epidemiology and SARS-CoV-2 variant dynamics in French Guiana, a tropical country located in South America. Our results suggest that wastewater-based epidemiology and genotyping are powerful tools to monitor variant introduction and disease evolution within a tropical country but the inclusion of both clinical and wastewater samples could still improve our understanding of genetic diversity co-circulating. Wastewater sequencing also revealed the cryptic transmission of SARS-CoV-2 variants within the country. Interestingly, we found some amino acid changes specific to the variants co-circulating in French Guiana, suggesting a local evolution of the SARS-CoV-2 variants after their introduction. More importantly, our results showed that the proximity to bordering countries was not the origin of the emergence of the French Guianese B.1.160.25 variant, but rather that this variant emerged from an ancestor B.1.160 variant introduced by European air plane travelers, suggesting thus that air travel remains a significant risk for cross-border spread of infectious diseases. Overall, we suggest that wastewater-based epidemiology and genotyping provides a cost effective and non-invasive approach for pathogen monitoring and an early-warning tool for disease emergence and spread within a tropical country.

Relationship between Presentation, Attitude, and In-Flight Meal Food Healthiness: Moderating Role of Familiarity.

This work focused on the perception of the food healthiness of in-flight meals. This work adopts presentation as the determinant. This work also employs attitude as the consequence of food healthiness. This research also examines the moderating effect of familiarity on the relationship between food presentation and food healthiness. This research used a survey, and survey participants were recruited via a Clickworker platform service. Survey participants were experienced with in-flight meals. The number of observations was 317. Moreover, this research tested the research hypotheses using the Hayes process macro Model 7. The results revealed that food healthiness is positively influenced by presentation and that food healthiness positively affects attitude. Moreover, the results revealed that the type of presentation has a positive influence on attitude. Familiarity was a significant moderating variable for the relationship between food presentation and food healthiness. This work sheds light on the literature by identifying the associations among four attributes of in-flight meals. Additionally, the results of this study could be used as a reference to develop better in-flight meals.