An investigation of the effects of sand and dust storms in the North East Sahara Desert on Turkish airports and PM10 values: 7 and 8 April, 2013 events.

Between April 7 and April 10, 2013, a cyclone with a value of 995 hPa that developed in the central Mediterranean transported dust from the Sahara Desert towards Turkey. At 13 airports in Turkey, dust haze and widespread dust were seen during different occasions in this period and caused the observation of so-called "Blowing dust events." This cyclone blew dust towards the Cappadocia airport, and the prevailing visibility decreased to 3800 m, making it the lowest value measured during the transition of this cyclone. In this study, Aviation Routine Weather Report (Metar) and Aviation Selected Special Weather Report (Speci) observations of airports in North Africa and Turkey were evaluated for the period between April 3 and April 11, 2013. With this cyclone the prevailing visibility at Benina Airport in Libya decreased to 50 m on April 6, 2013. This study aims to evaluate long-distance dust transport's effects on meteorological visibility at airports in Turkey and examine the episodic changes of PM10 values measured by air quality monitoring stations. Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model outputs were used to determine the trajectories of long-distance dust particles. Powder red, green, and blue (RGB) and Moderate Resolution Imaging Spectroradiometer (MODIS) satellite images, Cloud-Aerosol LIDAR Infrared Pathfinder Satellite Observations (CALIPSO) images, the Barcelona Supercomputing Center-Dust Regional Atmosphere Model (BSC-DREAM8b) outputs, and Global Forecast System (GFS) synoptic maps were used for analysis. In addition, PM10 values obtained from air quality monitoring stations were examined. According to the data obtained from the CALIPSO images, the dust concentration on the Eastern Mediterranean reaches up to 5 km. The episodic values obtained from certain air quality measurement stations are Adana 701, Gaziantep 629, Karaman 900, Nevsehir 1343, and Yozgat 782 µg/m3 on an hourly average.

COVID-19 cases reported in Colorado following screening at selected US airports, January - July 2020.

OBJECTIVE: We sought to estimate the proportion of air travelers who may have been infected with SARS-CoV-2 upon arrival to Colorado by comparing data on Colorado residents screened upon entering the US to COVID-19 cases reported in the state. Data on Colorado's screened passengers arriving into the US between January 17 and July 30, 2020 were compared to Colorado's Electronic Disease Reporting System. We conducted a descriptive analysis of true matches, including age, gender, case status, symptom status, time from arrival to symptom onset (days), and time from arrival to specimen collection date (days). RESULTS: Fourteen confirmed COVID-19 cases in travelers who were diagnosed within 14 days after arriving in Colorado were matched to the 8,272 travelers who underwent screening at 15 designated airports with a recorded destination of Colorado, or 0.2%. Most (N = 13/14 or 93%) of these infected travelers arrived in Colorado in March 2020; 12 (86%) of them were symptomatic. Entry screening for COVID-19 and the sharing of traveler information with the Colorado Department of Public Health and Environment appeared to identify few cases early in the pandemic. Symptom-based entry screening and sharing of traveler information was minimally effective at decreasing travel-associated COVID-19 transmission.

Models of Aviation Noise Impact in the Context of Operation Decrease at Tan Son Nhat Airport.

Air traffic bans in response to the spread of the coronavirus have changed the sound situation of urban areas around airports. This study aimed to investigate the effect of this unprecedented event on the community response to noise before and after the international flight operation at Tan Son Nhat Airport (TSN) in March 2020. The "before" survey was conducted in August 2019, and the two "after" surveys were conducted in June and September 2020. Structural equation models (SEMs) for noise annoyance and insomnia were developed by linking the questionnaire items of the social surveys. The first effort aimed to achieve a common model of noise annoyance and insomnia, corresponding to the situation before and after the change, respectively. Approximately, 1200 responses were obtained from surveys conducted in 12 residential areas around TSN in 2019 and 2020. The average daily flight numbers observed in August 2019 during the two surveys conducted in 2020 were 728, 413, and 299, respectively. The sound pressure levels of the 12 sites around TSN decreased from 45-81 dB (mean = 64, SD = 9.8) in 2019 to 41-76 dB (mean = 60, SD = 9.8) and 41-73 dB (mean = 59, SD = 9.3) in June and September 2020, respectively. The SEM indicated that the residents' health was related to increased annoyance and insomnia.

PFAS in fish from AFFF-impacted environments: Analytical method development and field application at a Canadian international civilian airport.

Methods targeting anionic per- and polyfluoroalkyl substances (PFAS) in aquatic biota are well established, but commonly overlook many PFAS classes present in aqueous film-forming foams (AFFFs). Here, we developed an analytical method for the expanded analysis of negative and positive ion mode PFAS in fish tissues. Eight variations of extraction solvents and clean-up protocols were first tested to recover 70 AFFF-derived PFAS from the fish matrix. Anionic, zwitterionic, and cationic PFAS displayed the best responses with methanol-based ultrasonication methods. The response of long-chain PFAS was improved for extracts submitted to graphite filtration alone compared with those involving solid-phase extraction. The validation included an assessment of linearity, absolute recovery, matrix effects, accuracy, intraday/interday precision, and trueness. The method was applied to a set of freshwater fish samples collected in 2020 in the immediate vicinity (creek, n = 15) and downstream (river, n = 15) of an active fire-training area at an international civilian airport in Ontario, Canada. While zwitterionic fluorotelomer betaines were major components of the subsurface AFFF source zone, they were rarely detected in fish, suggesting limited bioaccumulation potential. PFOS largely dominated the PFAS profile, with record-high concentrations in brook sticklebacks (Culaea inconstans) from the creek (16000-110,000 ng/g wet weight whole-body). These levels exceeded the Canadian Federal Environmental Quality Guidelines (FEQG) for PFOS pertaining to the Federal Fish Tissue Guideline (FFTG) for fish protection and Federal Wildlife Diet Guidelines (FWiDG) for the protection of mammalian and avian consumers of aquatic biota. Perfluorohexane sulfonamide and 6:2 fluorotelomer sulfonate were among the precursors detected at the highest levels (maximum of ∼340 ng/g and ∼1100 ng/g, respectively), likely reflecting extensive degradation and/or biotransformation of C6 precursors originally present in AFFF formulations.

Impact of airline network on the global importation risk of mpox, 2022.

From 1 January 2022 to 4 September 2022, a total of 53 996 mpox cases were confirmed globally. Cases are predominantly concentrated in Europe and the Americas, while other regions are also continuously observing imported cases. This study aimed to estimate the potential global risk of mpox importation and consider hypothetical scenarios of travel restrictions by varying passenger volumes (PVs) via airline travel network. PV data for the airline network, and the time of first confirmed mpox case for a total of 1680 airports in 176 countries (and territories) were extracted from publicly available data sources. A survival analysis technique in which the hazard function was a function of effective distance was utilised to estimate the importation risk. The arrival time ranged from 9 to 48 days since the first case was identified in the UK on 6 May 2022. The estimated risk of importation showed that regardless of the geographic region, most locations will have an intensified importation risk by 31 December 2022. Travel restrictions scenarios had a minor impact on the global airline importation risk against mpox, highlighting the importance to enhance local capacities for the identification of mpox and to be prepared to carry out contact tracing and isolation.

Spatial immunization to abate disease spreading in transportation hubs.

Proximity social interactions are crucial for infectious diseases transmission. Crowded agglomerations pose serious risk of triggering superspreading events. Locations like transportation hubs (airports and stations) are designed to optimize logistic efficiency, not to reduce crowding, and are characterized by a constant in and out flow of people. Here, we analyze the paradigmatic example of London Heathrow, one of the busiest European airports. Thanks to a dataset of anonymized individuals' trajectories, we can model the spreading of different diseases to localize the contagion hotspots and to propose a spatial immunization policy targeting them to reduce disease spreading risk. We also detect the most vulnerable destinations to contagions produced at the airport and quantify the benefits of the spatial immunization technique to prevent regional and global disease diffusion. This method is immediately generalizable to train, metro and bus stations and to other facilities such as commercial or convention centers.

Assessing the impact of aircraft arrival on ambient ultrafine particle number concentrations in near-airport communities in Boston, Massachusetts.

Aircraft emissions contribute to overall ambient air pollution, including ultrafine particle (UFP) concentrations. However, accurately ascertaining aviation contributions to UFP is challenging due to high spatiotemporal variability along with intermittent aviation emissions. The objective of this study was to evaluate the impact of arrival aircraft on particle number concentration (PNC), a proxy for UFP, across six study sites 3-17 km from a major arrival aircraft flight path into Boston Logan International Airport by utilizing real-time aircraft activity and meteorological data. Ambient PNC at all monitoring sites was similar at the median but had greater variation at the 95th and 99th percentiles with more than two-fold increases in PNC observed at sites closer to the airport. PNC was elevated during the hours with high aircraft activity with sites closest to the airport exhibiting stronger signals when downwind from the airport. Regression models indicated that the number of arrival aircraft per hour was associated with measured PNC at all six sites, with a maximum contribution of 50% of total PNC at a monitor 3 km from the airport during hours with arrival activity on the flight path of interest (26% across all hours). Our findings suggest strong but intermittent contributions from arrival aircraft to ambient PNC in communities near airports.

Sniffer dogs performance is stable over time in detecting COVID-19 positive samples and agrees with the rapid antigen test in the field.

Rapid antigen diagnostic (RAD) tests have been developed for the identification of the SARS-CoV-2 infection. However, they require nasopharyngeal or nasal swab, which is invasive, uncomfortable, and aerosolising. The use of saliva test was also proposed but has not yet been validated. Trained dogs may efficiently smell the presence of SARS-CoV-2 in biological samples of infected people, but further validation is needed both in laboratory and in field. The present study aimed to (1) assess and validate the stability over a specific time period of COVID-19 detection in humans' armpit sweat by trained dogs thanks to a double-blind laboratory test-retest design, and (2) assess this ability when sniffing people directly. Dogs were not trained to discriminate against other infections. For all dogs (n. 3), the laboratory test on 360 samples yielded 93% sensitivity and 99% specificity, an 88% agreement with the Rt-PCR, and a moderate to strong test-retest correlation. When sniffing people directly (n. 97), dogs' (n. 5) overall sensitivity (89%) and specificity (95%) were significantly above chance level. An almost perfect agreement with RAD results was found (kappa 0.83, SE 0.05, p = 0.001). Therefore, sniffer dogs met appropriate criteria (e.g., repeatability) and WHO's target product profiles for COVID-19 diagnostics and produced very promising results in laboratory and field settings, respectively. These findings support the idea that biodetection dogs could help reduce the spread of the virus in high-risk environments, including airports, schools, and public transport.

Multiobjective Gate Assignment Model Considering Carbon Emissions.

It has been a main concern for governments to reduce the carbon emission of the aviation industry. The paper proposes a multiobjective gate assignment model that considers the carbon emission at the airport surface to facilitate environmental-friendly airport construction. Three objectives are considered in the model to reduce carbon emissions, including the proportion of flights assigned to the contact gate, aircraft taxiing fuel consumption, and gate assignment robustness. In order to achieve better performance on all objectives, a Non-dominated Sorting Genetic Algorithm-II (NSGA-II) is used to obtain the optimal results. The operation data from a domestic airport is deployed to validate the model. The optimal results of the gate assignment model are compared with the original scheme. It indicates that the proposed model can effectively reduce carbon emissions. The study can provide a strategy for gate assignment to reduce carbon emissions and improve the management of the airport.

A novel resilience analysis methodology for airport networks system from the perspective of different epidemic prevention and control policy responses.

As the COVID-19 pandemic fades, the aviation industry is entering a fast recovery period. To analyze airport networks' post-pandemic resilience during the recovery process, this paper proposes a Comprehensive Resilience Assessment (CRA) model approach using the airport networks of China, Europe, and the U.S.A as case studies. The impact of COVID-19 on the networks is analyzed after populating the models of these networks with real air traffic data. The results suggest that the pandemic has caused damage to all three networks, although the damages to the network structures of Europe and the U.S.A are more severe than the damage in China. The analysis suggests that China, as the airport network with less network performance change, has a more stable level of resilience. The analysis also shows that the different levels of stringency policy in prevention and control measures during the epidemic directly affected the recovery rate of the network. This paper provides new insights into the impact of the pandemic on airport network resilience.

Effect of Predeparture Testing on Postarrival SARS-CoV-2-Positive Test Results Among International Travelers - CDC Traveler-Based Genomic Surveillance Program, Four U.S. Airports, March-September 2022.

Beginning December 6, 2021, all international air passengers boarding flights to the United States were required to show either a negative result from a SARS-CoV-2 viral test taken ≤1 day before departure or proof of recovery from COVID-19 within the preceding 90 days (1). As of June 12, 2022, predeparture testing was no longer mandatory but remained recommended by CDC (2,3). Various modeling studies have estimated that predeparture testing the day before or the day of air travel reduces transmission or importation of SARS-CoV-2 by 31%-76% (4-7). Postarrival SARS-CoV-2 pooled testing data from CDC's Traveler-based Genomic Surveillance program were used to compare SARS-CoV-2 test results among volunteer travelers arriving at four U.S. airports during two 12-week periods: March 20-June 11, 2022, when predeparture testing was required, and June 12-September 3, 2022, when predeparture testing was not required. In a multivariable logistic regression model, pooled nasal swab specimens collected during March 20-June 11 were 52% less likely to be positive for SARS-CoV-2 than were those collected during June 12-September 3, after adjusting for COVID-19 incidence in the flight's country of origin, sample pool size, and collection airport (adjusted odds ratio [aOR] = 0.48, 95% CI = 0.39-0.58) (p<0.001). These findings support predeparture testing as a tool for reducing travel-associated SARS-CoV-2 transmission and provide important real-world evidence that can guide decisions for future outbreaks and pandemics.

Cost-benefit analysis of micro WtE incinerator applications in an urban environment: A case study at the Hong Kong International Airport.

The globally located waste-to-energy (WtE) incinerators are generally of large capacities with high investments and long construction periods. This paper aims to evaluate the financial feasibility of micro WtE incinerators application in an urban environment using cost-benefit analysis (CBA). First, we propose a CBA method for such an application, considering two energy recovery methods. The advantage of carbon emission reduction over the existing disposal method is converted into monetary terms through a carbon trading system. Second, two facilities with different incineration technologies are considered. Six possible application scenarios are analyzed, taking into account differentiated benefit compositions. Third, a comprehensive sensitivity analysis is carried out to measure the impact of the parameter changes. Finally, the Hong Kong International Airport is applied as a case study. The results reveal the great potential for micro WtE incinerator applications in an urban environment, and the low-temperature magnetization facility has a comparative advantage over the high-temperature pyrolysis gasification facility.

Preparing for the Next Pandemic: An After-Action Review of Infection Prevention and Control Audit Strategies Within Airport and Hotel Quarantine Program.

BACKGROUND: Effective infection prevention and control (IPAC) practices within the New South Wales (NSW) Airport Operations and Hotel Quarantine Program (Quarantine Program) were required to mitigate the risk of COVID-19 being transmitted to staff, other guests, contractors, and the community. METHOD: The Quarantine Program relied on complex logistical arrangements and an end-to-end process that included all steps from the time travelers boarded the returning flight until completion of the quarantine period. This required compliance with relevant IPAC standards historically reserved for health care and the implementation of a quality assurance audit framework. RESULTS: The Clinical Excellence Commission (CEC) as the NSW Health Pillar for quality and safety and the lead in IPAC provided training and resources coupled with an IPAC quality audit framework after program commencement. CONCLUSION: This approach ensured a clear governance structure and a regular review process to minimize risk and support continuous improvement within the program.

Aircraft Noise Reduction Strategies and Analysis of the Effects.

In this study, six aircraft noise reduction strategies including the optimization of aircraft type, regulation of night flight number, optimization of flight procedure, modification of operating runway, land use planning and installation of sound insulation windows were proposed to alleviate the harmful impact of aircraft noise on the local area and population near Guangzhou Baiyun International Airport (BIA) in China. The effects of all proposed strategies except for land use planning and sound insulation windows were simulated and analyzed using CadnaA software. The results indicate that these noise reduction strategies have their own advantages and each of them can serve as an effective noise reduction measure for different applications. For instance, the replacement of noisy aircraft with low-noise aircraft can simultaneously reduce the area and population exposed to a high noise level, while the optimization of flight procedure can only reduce the population exposed under relatively low noise levels (70 ≤LWECPN ≤ 75 dB). Nevertheless, the modification of operating runway is more effective in reducing the population suffering under high noise levels (LWECPN > 85 dB). Among these strategies, reducing the number of night flights is found to be most effective in reducing the overall noise-exposed area and population. Additionally, with the assistance of noise mapping, proper land use planning was suggested according to national standards, and the installation of sound insulation windows with different sound reduction grades can be determined for different areas impacted by the aircraft noise of BIA. It is believed that the results of this study can be applied as a reference in selecting suitable noise reduction strategies to improve the acoustic environment of a specific airport.

Travelers' Subjective Well-Being as an Environmental Practice: Do Airport Buildings' Eco-Design, Brand Engagement, and Brand Experience Matter?

The physical environment of airports plays a crucial role in improving travelers' perceptions and well-being. Adopting a green physical environment may elicit customers' cognitive and emotional responses and provide a convenient consumption environment. Brand experience and engagement are other important consumer-firm interactions that influence the attributes of the passengers' well-being. The current study sought to assess the impact of the eco-design of buildings, brand experience and engagement on the well-being of travelers at an international airport in Saudi Arabia. Additionally, the current study investigated the possible effects of eco-design on airport experience and engagement. The results of the structural equation modeling analysis revealed that the eco-design of airport buildings was independently associated with passengers' well-being and brand engagement, but not with brand experience. Additionally, well-being was significantly predicted by brand engagement and experience. Airport managers are advised to adopt an internal eco-design to help promote passengers' connection with the brand and improve their well-being, which would eventually be reflected in their behavioral attributes and decision-making.

High-resolution processing and sigmoid fusion modules for efficient detection of small objects in an embedded system.

Recent advances in deep learning realized accurate, robust detection of various types of objects including pedestrians on the road, defect regions in the manufacturing process, human organs in medical images, and dangerous materials passing through the airport checkpoint. Specifically, small object detection implemented as an embedded system is gaining increasing attention for autonomous vehicles, drone reconnaissance, and microscopic imagery. In this paper, we present a light-weight small object detection model using two plug-in modules: (1) high-resolution processing module (HRPM ) and (2) sigmoid fusion module (SFM). The HRPM efficiently learns multi-scale features of small objects using a significantly reduced computational cost, and the SFM alleviates mis-classification errors due to spatial noise by adjusting weights on the lost small object information. Combination of HRPM and SFM significantly improved the detection accuracy with a low amount of computation. Compared with the original YOLOX-s model, the proposed model takes a two-times higher-resolution input image for higher mean average precision (mAP) using 57% model parameters and 71% computation in Gflops. The proposed model was tested using real drone reconnaissance images, and provided significant improvement in detecting small vehicles.

Exploring the Transmission Path, Influencing Factors and Risk of Aerosol Transmission of SARS-CoV-2 at Xi'an Xianyang International Airport.

SARS-CoV-2 genetic sequence results collected from native COVID-19 cases who waited or saw relatives off at Xi'an Xianyang International Airport were highly consistent with the imported cases. In order to explore the routes of transmission and influencing factors that may cause the transmission of SARS-CoV-2 at the airport, a field simulation experiment of aerosol diffusion was adopted based on epidemiological survey data and a detailed field investigation of airport structure and ventilation. The results showed that the inbound passengers waited for approximately 3 h in the rest area on the first level of the international arrival area (Zone E). During the period, masks were removed for eating and drinking, resulting in the viral aerosols rising from the first level to the second level with hot air. After deplaning, the inbound passengers handled the relevant procedures and passed through the corridor on the second floor. The local side wall of the corridor adopted fan coil air conditioning, combined with fresh air supply and personnel walking, resulting in airflow flowing to Zone E. After merging with diffused air containing virus aerosol from the first floor, it continued to spread upward to the connected third-layer area. There was a local suspended ceiling on the top of the third floor, but it was approximately 4 m high and connected to the corridor from Terminal 2 to Terminal 3. When the virus aerosol diffused above the Terminal 2-Terminal 3 corridor, where the temperature was low and the air diffused downward, it could cause an infection risk for people passing through the corridor. In addition, the investigation found that the exhaust pipes of the nucleic acid sampling rooms at the international arrival corridor were directly discharged outdoors without treatment. Only one exhaust pipe and poor ventilation in the bathroom in Zone E had a risk of viral aerosol diffusion. Therefore, the international arrival area should be set up alone or separated from the other areas by hard isolation to avoid the existence of communication between different areas that could cause viral aerosols to diffuse with airflow. The toilet ventilation should be increased to avoid the accumulation of viral aerosols at high concentrations. The exhaust pipes of the toilet and the nucleic acid sampling rooms should be equipped with disinfection and efficient filtration devices, and high-altitude emission should be adopted to reduce the risk of virus aerosol diffusion.

Detection of Monkeypox Virus DNA in Airport Wastewater, Rome, Italy.

Environmental surveillance can be a complementary tool for detecting pathogens circulating in communities. We detected monkeypox virus DNA in wastewater from Italy's largest airport by using real-time PCR assays targeting the G2R region and F3L and N3R genes and sequencing. Wastewater surveillance can be quickly adapted to investigate emerging threats.