RESUMO
Surgical resection of esophageal cancer may result in benign anastomotic strictures, which are usually treated by balloon dilatation. Here we reported the long-term outcomes of large balloon dilatation for benign anastomotic strictures secondary to esophagectomy for esophageal cancer. From February 2011 to December 2016, 27 esophageal cancer patients underwent large balloon dilatation for benign strictures following surgical resection. Clinical success rate, number of dilatation sessions, complication rate, and mortality rate were evaluated. A total of 27 patients developed a benign stricture at the esophagectomy site. A total of 50 dilatation sessions of large balloon were performed, with a mean of 1.8 sessions per patients (range 1.0-5.0). Only 1 perforation was observed (2.0% per dilatation session), and required no surgery. No procedure-related deaths were recorded. Large balloon dilation was technically successful in the remained 26 patients (96.3%). Dysphagia score and stricture index decreased significantly (P < .0001). Proximal diameter of stricture, stricture diameter and length decreased significantly. Patients were followed up for 36.3 ± 7.1 months, and 14 patients survived without dysphagia. The survival rates were 95.0%, 69.1%, 34.5% for 1, 5, and 9 years, respectively. The median survival was 96.0 months. Large balloon dilatation can be a safe and feasible treatment for benign anastomic strictures following surgical resection of esophageal cancer, with a low perforation rate. However, further study compared with small balloon dilatation is warranted.
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Transtornos de Deglutição , Neoplasias Esofágicas , Humanos , Constrição Patológica , Dilatação , Neoplasias Esofágicas/cirurgia , AeronavesRESUMO
The human pathogenic bacteria Bacillus cereus, Bacillus anthracis and the entomopathogenic Bacillus thuringiensis form spores encased in a protein coat surrounded by a balloon-like exosporium. These structures mediate spore interactions with its environment, including the host immune system, control the transit of molecules that trigger germination and thus are essential for the spore life cycle. Formation of the coat and exosporium has been traditionally visualized by transmission electronic microscopy on fixed cells. Recently, we showed that assembly of the exosporium can be directly observed in live B. cereus cells by super resolution-structured illumination microscopy (SR-SIM) using the membrane MitoTrackerGreen (MTG) dye. Here, we demonstrate that the different steps of coat formation can also be visualized by SR-SIM using MTG and SNAP-cell TMR-star dyes during B. cereus sporulation. We used these markers to characterize a subpopulation of engulfment-defective B. cereus cells that develops at a suboptimal sporulation temperature. Importantly, we predicted and confirmed that synthesis and accumulation of coat material, as well as synthesis of the σK-dependent protein BxpB, occur in cells arrested during engulfment. These results suggest that, unlike the well-studied model organism Bacillus subtilis, the activity of σK is not strictly linked to the state of forespore development in B. cereus.
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Bacillus anthracis , Cactaceae , Humanos , Bacillus cereus , Aeronaves , Bacillus subtilis , Corantes , Microscopia Eletrônica de TransmissãoRESUMO
The Korean War was the first conflict in which helicopters were used extensively for casualty evacuation but their contribution to medical evacuation at that time is disputed. On the one hand, many cases undoubtedly survived because of helicopter transportation; on the other, the proportion of casualties evacuated appears to have been small and difficult to determine precisely. Taking the British army as a case study, this article looks more closely at arrangements for casualty evacuation in Korea, assessing the role of helicopters in relation to other elements of the evacuation system and its operation as a whole. The article is divided into several sections. The first examines the command structure of the medical system in Korea, which extended as far back as hospitals in Japan. It shows how medical support for British forces was closely integrated with that of other Commonwealth forces. It notes that rapid and effective integration was a major factor in the success of medical evacuation because it allowed ideas and equipment to be shared easily and because it fostered a spirit of cooperation. This section also highlights the Second World service of all senior Commonwealth medical officers as a factor conducive to integration. The second section provides an overview of the chain of evacuation from the frontline to hospitals in Japan. It describes the functions of the different medical institutions along the chain and how they were connected. Among other things, it shows how the chain for British and Commonwealth troops intersected with medical units of the United States such as Mobile Army Surgical Hospitals and hospital trains. In the third section of the article, there is a detail examination of evacuation by helicopter, describing how it was arranged, what its limitations were, and what types of casualty were evacuated. It estimates the proportion of casualties that were evacuated by this means. The fourth and fifth sections highlight the importance of command decisions in the effective working of the evacuation system. The fourth concentrates on the evolution of a system of forward treatment of minor cases, looking at the challenge posed by disease and other non-battle casualties. The fifth and final section of the article describes how the system of evacuation functioned as a whole, including the different means used to carry the sick and wounded in addition to helicopters. It stresses the importance of coordination between these different elements and places particular emphasis on the value of wireless communications. The article concludes that the success of casualty evacuation in Korea depended less on any single method of transportation than on effective command and control. In this respect, communication between constituent units of the evacuation chain and cooperation between British and other UN forces was crucial. Of equal and perhaps even greater importance was the decision to implement a policy of forward treatment of sickness and minor injuries. Without such a policy, the lines of evacuation would inevitably have become congested, having a detrimental effect on casualty survival rates. This policy drew on the lessons of the two world wars which were still relatively fresh in the minds of medical commanders. Although far less striking than the advent of the helicopter, prior knowledge of coalition warfare and the handling of mass casualties was crucial to medical success. If there is a lesson to be learned from the Korean War for own times, it is probably this.
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Aeronaves , Comunicação , Estados Unidos , Dissidências e Disputas , Hospitais Militares , República da CoreiaRESUMO
INTRODUCTION: A broad range of pathophysiologic conditions can lead to cardiopulmonary arrest in children. Some of these children suffer from refractory cardiac arrest, not responding to basic and advanced life support. Extracorporeal-Cardiopulmonary Resuscitation (E-CPR) might be a life-saving option for this group. Currently this therapy is only performed in-hospital, often necessitating long transport times, thereby negatively impacting eligibility and chances of survival. We present the first two cases of prehospital E-CPR in children performed by regular Helicopter Emergency Medical Services (HEMS). CASE PRESENTATIONS: The first patient was a previously healthy 7 year old boy who was feeling unwell for a couple of days due to influenza. His course deteriorated into a witnessed collapse. Direct bystander CPR and subsequent ambulance advanced life support was unsuccessful in establishing a perfusing rhythm. While doing chest compressions, the patient was seen moving both his arms and making spontaneous breathing efforts. Echocardiography however revealed a severe left ventricular impairment (near standstill). The second patient was a 15 year old girl, known with bronchial asthma and poor medication compliance. She suffered yet another asthmatic attack, so severe that she progressed into cardiac arrest in front of the attending ambulance and HEMS crews. Despite maximum bronchodilator therapy, intubation and the exclusion of tension pneumothoraxes and dynamic hyperinflation, no cardiac output was achieved. INTERVENTION: After consultation with the nearest paediatric E-CPR facilities, both patients were on-scene cannulated by regular HEMS. The femoral artery and vein were cannulated (15-17Fr and 21Fr respectively) under direct ultrasound guidance using an out-of-plane Seldinger approach. Extracorporeal Life Support flow of 2.1 and 3.8 l/min was established in 20 and 16 min respectively (including preparation and cannulation). Both patients were transported uneventfully to the nearest paediatric intensive care with spontaneous breathing efforts and reactive pupils during transport. CONCLUSION: This case-series shows that a properly trained regular HEMS crew of only two health care professionals (doctor and flight nurse) can establish E-CPR on-scene in (older) children. Ambulance transport with ongoing CPR is challenging, even more so in children since transportation times tend to be longer compared to adults and automatic chest compression devices are often unsuitable and/or unapproved for children. Prehospital cannulation of susceptible E-CPR candidates has the potential to reduce low-flow time and offer E-CPR therapy to a wider group of children suffering refractory cardiac arrest.
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Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca , Adulto , Masculino , Feminino , Humanos , Criança , Adolescente , Estudos de Viabilidade , AeronavesRESUMO
Vertebrate macroevolution has been punctuated by fundamental habitat transitions from shallow marine origins to terrestrial, freshwater, and aerial environments. Invasion of the deep sea is a less well-known ecological shift because of low fossilization potential and continual loss of abyssal fossil record by ocean floor subduction. Therefore, there has been a lack of convincing evidence of bottom-living vertebrates from pre-Paleogene deep seas. Here, we describe trace fossils from abyssal plain turbidites of the Tethys Ocean, which, combined with nannofossil dating, indicate that fishes have occupied the deep seafloor since at least the Early Cretaceous (Hauterivian-Barremian). These structures are identical to those produced by modern demersal fishes that feed by either scratching the substrate or expose their prey by water flow generated by suction or jetting. The trace fossils suggest activity of at least three fish species exploiting a productive abyssal invertebrate sediment fauna. These observations are consistent with Early Cretaceous vertebrate transition to the deep sea triggered by the availability of new food sources. Our results anticipate the appearance of deep-seafloor fishes in the fossil record by over 80 My while reassessing the mode of vertebrate colonization of the deep sea.
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Aeronaves , Vertebrados , Animais , Alimentos , Fósseis , Água DoceRESUMO
BACKGROUND: SARS-CoV-2 can be effectively transmitted between individuals located in close proximity to each other for extended durations. Aircraft provide such conditions. Although high attack rates during flights were reported, little was known about the risk levels of aerosol transmission of SARS-CoV-2 in aircraft cabins. OBJECTIVES: The major objective was to estimate the risk of contracting COVID-19 from transmission of aerosol particles in aircraft cabins. METHODS: In two single-aisle and one twin-aisle aircraft, dispersion of generated aerosol particles over a seven-row economy class cabin section was measured under cruise and taxi conditions and simulated with a computational fluid dynamic model under cruise conditions. Using the aerosol particle dispersion data, a quantitative microbial risk assessment was conducted for scenarios with an asymptomatic infectious person expelling aerosol particles by breathing and speaking. Effects of flight conditions were evaluated using generalized additive mixed models. RESULTS: Aerosol particle concentration decreased with increasing distance from the infectious person, and this decrease varied with direction. On a typical flight with an average shedder, estimated mean risk of contracting COVID-19 ranged from 1.3×10-3 to 9.0×10-2. Risk increased to 7.7×10-2 with a super shedder (<3% of cases) on a long flight. Risks increased with increasing flight duration: 2-23 cruise flights of typical duration and 2-10 flights of longer duration resulted in at least 1 case of COVID-19 due to onboard aerosol transmission by one average shedder, and in the case of one super shedder, at least 1 case in 1-3 flights of typical duration cruise and 1 flight of longer duration. DISCUSSION: Our findings indicate that the risk of contracting COVID-19 by aerosol transmission in an aircraft cabin is low, but it will not be zero. Testing before boarding may help reduce the chance of a (super)shedder boarding an aircraft and mask use further reduces aerosol transmission in the aircraft cabin. https://doi.org/10.1289/EHP11495.
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COVID-19 , Humanos , SARS-CoV-2 , Aerossóis e Gotículas Respiratórios , Aeronaves , Medição de RiscoRESUMO
BACKGROUND: Trauma related deaths remain a relevant public health problem, in particular in the younger male population. A significant number of these deaths occur prehospitally without transfer to a hospital. These patients, sometimes termed "the forgotten cohort", are usually not included in clinical registries, resulting in a lack of information about prehospitally trauma deaths. The aim of the present study was to compare patients who died prehospital with those who sustained life-threatening injuries in order to analyze and potentially improve prehospital strategies. METHODS: This cohort study included all primary operations carried out by Switzerland's largest helicopter emergency medical service (HEMS) between January 1, 2011, and December 31, 2021. We included all adult trauma patients with life-threatening or fatal conditions. The outcome of this study is the vital status of the patient at the end of mission, i.e. fatal or life-threatening. Injury, rescue characteristics, and interventions of the forgotten trauma cohort, defined as patients with a fatal injury (NACA score of VII), were compared with life-threatening injuries (NACA score V and VI). RESULTS: Of 110,331 HEMS missions, 5534 primary operations were finally analyzed, including 5191 (93.8%) life-threatening and 343 (6.2%) fatal injuries. More than two-thirds of patients (n = 3772, 68.2%) had a traumatic brain injury without a significant difference between the two groups (p > 0.05). Thoracic trauma (44.6% vs. 28.7%, p < 0.001) and abdominal trauma (22.2% vs. 16.1%, p = 0.004) were more frequent in fatal missions whereas pelvic trauma was similar between the two groups (13.4% vs. 12.9%, p = 0.788). Pneumothorax decompression rate (17.2% vs. 3.7%, p < 0.001) was higher in the forgotten cohort group and measures for bleeding control (15.2% vs. 42.7%, p < 0.001) and pelvic belt application (2.9% vs. 13.1% p < 0.001) were more common in the life-threating injury group. CONCLUSION: Chest decompression rates and measures for early hemorrhage control are areas for potential improvement in prehospital care.
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Resgate Aéreo , Serviços Médicos de Emergência , Adulto , Humanos , Masculino , Estudos de Coortes , Estudos Retrospectivos , Serviços Médicos de Emergência/métodos , AeronavesRESUMO
Aviation safety depends on the skill and expertise of pilots to meet the task demands of flying an aircraft in an effective and efficient manner. During flight training, students may respond differently to imposed task demands based on individual differences in capacity, physiological arousal, and effort. To ensure that pilots achieve a common desired level of expertise, training programs should account for individual differences to optimize pilot performance. This study investigates the relationship between task performance and physiological correlates of effort in ab initio pilots. Twenty-four participants conducted a flight simulator task with three difficulty levels and were asked to rate their perceived demand and effort using the NASA TLX. We recorded heart rate, EEG brain activity, and pupil size to assess changes in the participants' mental and physiological states across different task demands. We found that, despite group-level correlations between performance error and physiological responses, individual differences in physiological responses to task demands reflected different levels of participant effort and task efficiency. These findings suggest that physiological monitoring of student pilots might provide beneficial insights to flight instructors to optimize pilot training at the individual level.
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Aviação , Pilotos , Humanos , Individualidade , Aeronaves , Frequência CardíacaRESUMO
Unique identification of machine parts is critical to production and maintenance, repair and overhaul (MRO) processes in the aerospace industry. Despite recent advances in automating these identification processes, many are still performed manually. This is time-consuming, labour-intensive and prone to error, particularly when dealing with visually similar objects that lack distinctive features or markings or when dealing with parts that lack readable identifiers due to factors such as dirt, wear and discolouration. Automation of these processes has the potential to alleviate these problems. However, due to the high visual similarity of components in the aerospace industry, commonly used object identifiers are not directly transferable to this domain. This work focuses on the challenging component spectrum engine tubes and aims to understand which identification method using only object-inherent properties can be applied to such problems. Therefore, this work investigates and proposes a comprehensive set of methods using 2D image or 3D point cloud data, incorporating digital image processing and deep learning approaches. Each of these methods is implemented to address the identification problem. A comprehensive benchmark problem is presented, consisting of a set of visually similar demonstrator tubes, which lack distinctive visual features or markers and pose a challenge to the different methods. We evaluate the performance of each algorithm to determine its potential applicability to the target domain and problem statement. Our results indicate a clear superiority of 3D approaches over 2D image analysis approaches, with PointNet and point cloud alignment achieving the best results in the benchmark.
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Aeronaves , Algoritmos , Automação , Processamento de Imagem Assistida por ComputadorRESUMO
INTRODUCTION: The modern aircraft cockpit has evolved into a complex system of systems. Numerous performance evaluation metrics and techniques exist that can measure the effectiveness of cockpit components in terms of how they influence the human operator's ability to perform tasks relevant to mission success. As no prior review of these metrics has been found in the literature, this effort attempts to do so, albeit without applying the metrics to a novel cockpit evaluation.METHODS: These metrics and techniques are discussed and presented in five defined categories as they relate to evaluating cockpit subsystems: ergonomics and anthropometrics; human-computer interaction; data management and presentation; crew resource management and operations; and ingress and egress.DISCUSSION: While this effort is significant and novel, it is not necessarily comprehensive. In conclusion, it is noted that no single holistic quantitative metric to evaluate cockpit design and performance yet exists. Utilizing some of the preexisting metrics presented to develop such a metric would be beneficial in efforts to evaluate aircraft cockpit designs and performance, as well as aiding future cockpit designs.Brighton EM, Klaus DM. Categorization of select cockpit performance evaluation techniques. Aerosp Med Hum Perform. 2023; 94(9):696-704.
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Aeronaves , Ergonomia , Humanos , AntropometriaRESUMO
BACKGROUND: The COVID-19 pandemic from 2019 to 2022 devastated many aspects of life and the economy, with the commercial aviation industry being no exception. One of the major concerns during the pandemic was the degree to which the internal aircraft environment contributed to virus transmission between humans and, in particular, the stability of SARS-CoV-2 on contact surfaces in the aircraft cabin interior. METHOD: In this study, the stability of various major strains of SARS-CoV-2 on interior aircraft surfaces was evaluated using the TCID50 assessment. RESULTS: In contrast to terrestrial materials, SARS-CoV-2 was naturally less stable on common contact points in the aircraft interior, and, over a 4 h time period, there was a 90% reduction in culturable virus. Antiviral and surface coatings were extremely effective at mitigating the persistence of the virus on surfaces; however, their benefit was diminished by regular cleaning and were ineffective after 56 days of regular use and cleaning. Finally, successive strains of SARS-CoV-2 have not evolved to be more resilient to survival on aircraft surfaces. CONCLUSIONS: We conclude that the mitigation strategies for SARS-CoV-2 on interior aircraft surfaces are more than sufficient, and epidemiological evidence over the past three years has not found that surface spread is a major route of transmission.
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Aviação , COVID-19 , Humanos , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pandemias , AeronavesRESUMO
Closing the static suborbital debris hazard zone method leads to low airspace resource utilization and long delays for civil aircraft, while the dynamic delineation of suborbital debris hazard zone method can solve the above phenomena. However, the existing research lacks the decision instruction for civil aircraft to avoid the dynamic suborbital debris hazard zone. To address the above problems, this paper creates probability ellipsoids of suborbital debris with different ballistic coefficients in the two-dimensional plane and use the divide-and-conquer algorithm for the dynamic delineation of the suborbital debris hazard zone. The suborbital debris hazard zone is extended outward by 10 km. Subsequently, the standard A* algorithm, the standard Lazy theta* algorithm, the improved Lazy theta* algorithm, and a flight path planning strategy are designed to avoid the suborbital debris hazard zone and provide safe dynamic avoidance commands for civil aircraft with fixed time intervals. The simulation results show that the average area of the dynamically delineated suborbital debris hazard zone is lower than the traditional static no-fly zone; the standard A* algorithm and improved Lazy theta* algorithm provides shorter flight path lengths and flight time and fewer waypoints in windless and windy conditions, respectively.
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Aeronaves , Algoritmos , Simulação por Computador , Probabilidade , VentoRESUMO
In social animals, success can depend on the outcome of group battles. Theoretical models of warfare predict that group fighting ability is proportional to two key factors: the strength of each soldier in the group and group size. The relative importance of these factors is predicted to vary across environments [F. W. Lanchester, Aircraft in Warfare, the Dawn of the Fourth Arm (1916)]. Here, we provide an empirical validation of the theoretical prediction that open environments should favor superior numbers, whereas complex environments should favor stronger soldiers [R. N. Franks, L. W. Partridge, Anim. Behav. 45, 197-199 (1993)]. We first demonstrate this pattern using simulated battles between relatively strong and weak soldiers in a computer-driven algorithm. We then validate this result in real animals using an ant model system: In battles in which the number of strong native meat ant Iridomyrmex purpureus workers is constant while the number of weak non-native invasive Argentine ant Linepithema humile workers increases across treatments, fatalities of I. purpureus are lower in complex than in simple arenas. Our results provide controlled experimental evidence that investing in stronger soldiers is more effective in complex environments. This is a significant advance in the empirical study of nonhuman warfare and is important for understanding the competitive balance among native and non-native invasive ant species.
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Aeronaves , Formigas , Animais , Algoritmos , Pesquisa Empírica , Espécies IntroduzidasRESUMO
An analysis has been carried out to investigate the sound radiation through a heated jet in cooler cross-flow, which is representative of many industrial exhaust systems, using a hybrid steady-state computational fluid dynamics and computational acoustic model. The mean flow and temperature fields are modelled using steady-state computational fluid dynamics, with the turbulence modelled using Reynolds Averaged Navier-Stokes equations. The corresponding mean flow and temperature fields are used in the computational sound propagation model using linearised acoustic wave equation with mean flow based on a scalar flow potential. The results obtained from the computational simulations show that the flow significantly changes the sound propagation path and that the sound levels downstream of the duct outlet are higher than expected from using an acoustic monopole radiation pattern. The dominant mechanism affecting the propagation of sound is the refraction arising from the plume's temperature and velocity gradients. The sound propagation is highly dependent on the proximity from the duct outlet, normalised wavenumber, temperature and the jet to cross-flow mean velocity ratio. This computational study builds upon previous experimental work to analyse the fluid-acoustic interaction for heated jets in cooler cross-flow to understand the complex radiation pattern that leads to higher-than-expected sound levels downstream of the duct outlet.
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Acústica , Som , Aeronaves , Hidrodinâmica , Temperatura AltaRESUMO
Atmospheric pressure plasma jets with cross-field electrode configuration are a potential jet design for gases with high breakdown fields. This study focuses on the effect of an additional floating electrode on the cross-field plasma jet properties. Detailed experiments are done with the additional floating electrodes of different widths introduced below the ground electrode in a plasma jet with a cross-field electrode configuration. It is observed that in the presence of an additional floating electrode in the jet propagation path, less applied power is needed for the plasma jet to cross the nozzle and jet length increases. This threshold power, as well as the maximum jet length, depends on the electrode widths. A detailed analysis of charge dynamics in the presence of an additional floating electrode shows decrement in the net charge transferred radially to the external circuit through the ground electrode, and an increment in the net charge transferred axially. Increment in the optical emission intensity of reactive oxygen and nitrogen species, as well as the relative yield of ions like N[Formula: see text], O[Formula: see text], OH[Formula: see text], NO[Formula: see text], O[Formula: see text], and OH[Formula: see text] in the plasma plume, that are crucial for biomedical applications suggest an improvement in the reactivity of plasma plume in the presence of additional floating electrode.
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Aeronaves , Pressão Atmosférica , Eletrodos , Gases , NitrogênioRESUMO
BACKGROUND: There is increasing evidence for adverse health effects associated with aircraft-emitted particulate matter (PM) exposures, which are largely in the ultrafine (PM0.1) size fraction, but no previous study has examined neurodevelopmental outcomes. OBJECTIVE: To assess associations between maternal exposure to aircraft ultrafine particles (UFP) during pregnancy and offspring autism spectrum disorder (ASD) diagnosis. METHODS: This large, representative cohort study included 370,723 singletons born in a single healthcare system. Demographic data, maternal health information, and child's ASD diagnosis by age 5 were extracted from electronic medical records. Aircraft exposure estimates for PM0.1 were generated by the University of California Davis/California Institute of Technology Source Oriented Chemical Transport model. Cox proportional hazard models were used to assess associations between maternal exposure to aircraft PM0·1 in pregnancy and ASD diagnosis, controlling for covariates. RESULTS: Over the course of follow-up, 4,554 children (1.4 %) were diagnosed with ASD. Increased risk of ASD was associated with maternal exposure to aircraft PM0.1 [hazard ratio, HR: 1.02, (95 % confidence interval (CI): 1.01-1.03) per IQR = 0.02 µg/m3 increase during pregnancy. Associations were robust to adjustment for total PM0.1 and fine particulate matter (PM2.5), near-roadway air pollution, and other covariates. Noise adjustment modestly attenuated estimates of UFP effects, which remained statistically significant. DISCUSSION: The results strengthen the emerging evidence that maternal particulate matter exposure during pregnancy is associated with offspring ASD diagnosis and identify aircraft-derived PM0.1 as novel targets for further study and potential regulation.
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Poluentes Atmosféricos , Poluição do Ar , Transtorno do Espectro Autista , Gravidez , Feminino , Humanos , Criança , Pré-Escolar , Material Particulado/efeitos adversos , Material Particulado/análise , Exposição Materna/efeitos adversos , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Transtorno do Espectro Autista/epidemiologia , Transtorno do Espectro Autista/etiologia , Estudos de Coortes , Poluição do Ar/análise , Aeronaves , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análiseAssuntos
Resgate Aéreo , Dispositivos Aéreos não Tripulados , Humanos , Pegada de Carbono , AeronavesRESUMO
We analyzed the characteristics of sustained attention changes in flight crews during exempt and non-exempt flights. Fourteen pilots (aged 30-43 y) participated in this study, with seven involved in each flight type, all of which were intercontinental (China to North America). Pilots completed continuous performance tests (CPT) at the required flight stages without compromising safety while on duty. No significant differences in sleep and sustained attention emerged between the exempt and non-exempt flight crews. Pilots' fatigue was highest in the early morning hours. Their general stability of efficiency increased during the day and decreased at night. Non-exempt flight crews appeared to sacrifice reaction rate to improve accuracy. Exempt crews appeared to increase their test proficiency. The task stability time of the non-exempt flight crews was better than that of the exempt ones. Short-term stability was better for exempt inbound flights rather than for outbound ones. Pilots were more prone to error runs as their total time awake increased, especially on non-exempt flights. The addition of crew members to exempt flights, allowance for more in-flight rest shifts, and over-stop rest on non-exempt flights may alleviate pilot fatigue and preserve alertness.
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Aeronaves , Privação do Sono , Humanos , Ritmo Circadiano , Tolerância ao Trabalho Programado , Sono , Atenção , FadigaRESUMO
INTRODUCTION: Several studies have shown the additional benefit of point-of-care ultrasound (POCUS) by prehospital Emergency Medical Services (EMS). Since organization of EMS may vary significantly across countries, the value of POCUS likely depends on the prehospital system in which it is used. In order to be able to optimally implement POCUS and develop a tailored training curriculum, it is important to know how often POCUS is currently used, for which indications it is used, and how it affects decision making. The aims of this study were: (1) to determine the percentage of patients in whom POCUS was used by Dutch Helicopter Emergency Medical Services (HEMS) crews; (2) to determine how often POCUS findings led to changes in on-scene management; and (3) what these changes were. METHODS: Patients who received prehospital care from December 1, 2020 through March 31, 2021 by a single HEMS crew were included in this prospective cohort study. Clinical data and specific data on POCUS examination, findings, and therapeutic consequences were collected and analyzed. RESULTS: During the study period, on-scene HEMS care was provided to 612 patients, of which 211 (34.5%) patients underwent POCUS. Of these, 209 (34.2%) patients with a median age of 45 years were included. There were 131 (62.7%) trauma patients, and 70 (33.7%) of the included patients underwent cardiopulmonary resuscitation (CPR). The median reported time of POCUS examination was three (P25-P75 2-5) minutes. Median prolongation of on-scene time was zero (P25-P75 0-1) minutes. In 85 (40.7%) patients, POCUS examination had therapeutic consequence: POCUS was found to impact treatment decisions in 34 (26.0%) trauma patients and 51 (65.4%) non-trauma patients. In patients with cardiac arrest, POCUS was most often used to aid decision making with regard to terminating or continuing resuscitation (28 patients; 13.4%). CONCLUSION: During the study period, POCUS examination was used in 34.5% of all prehospital HEMS patients and had a therapeutic consequence in 40.7% of patients. In trauma patients, POCUS seems to be most effective for patient triage and evaluation of treatment effectiveness. Moreover, POCUS can be of significant value in patients undergoing CPR. A tailored HEMS POCUS training curriculum should include ultrasound techniques for trauma and cardiac arrest.
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Resgate Aéreo , Serviços Médicos de Emergência , Parada Cardíaca , Médicos , Humanos , Pessoa de Meia-Idade , Sistemas Automatizados de Assistência Junto ao Leito , Estado Terminal/terapia , Estudos Prospectivos , Aeronaves , Tomada de Decisões , Estudos RetrospectivosRESUMO
Operating an aircraft requires pilots to handle a significant amount of multi-modal information, which creates a high working memory load. Detecting auditory alarms in this high-load scenario is crucial for aviation safety. According to cognitive control load theory, an increase in working memory load may enhance distractor interference, resulting in improved detection sensitivity for task-irrelevant stimuli. Therefore, understanding the effect of working memory load on auditory alarm detection is of particular interest in aviation safety research. The studies were designed to investigate the effect of storage load and executive function load of working memory on auditory alarm detection during aeronautical decision-making through three experiments. In Experiment 1 and 2, participants performed an aeronautical decision-making task while also detecting an auditory alarm during the retention interval of a working memory task (visual-spatial, visual-verbal and auditory-verbal). In Experiment 3, participants were required to detect an auditory alarm while performing the 2-back and 3-back aeronautical decision-making tasks. Experiment 1 found that the auditory alarm sensitivity was higher in conditions of low visual-spatial working memory storage load compare to high load conditions. Experiment 2 found that a high storage load of visual-verbal working memory reduced auditory alarm sensitivity but auditory-verbal working memory load did not. Experiment 3 found that, unlike storage load, auditory alarm sensitivity was stronger under high executive function load relative to low executive function load. These findings show that working memory storage load and executive function load have different effects on auditory alarm sensitivity. The relationship between executive function and auditory alarm sensitivity supports cognitive control load theory, while the impact of the storage function on auditory alarm sensitivity does not adhere to this theory.