How job stressors and economic stressors impact public transport drivers' performance and well-being under the health risk of the COVID-19 pandemic.

INTRODUCTION: During the COVID-19 pandemic, public transport (e.g., bus and taxi) drivers encountered great stress because they needed to work to maintain the operation of the transportation system. This study proposes and empirically investigates the impacts of job stressors and economic stressors of public transport drivers on emotional exhaustion, and subsequent psychological well-being and performance under the health risk of COVID-19. The moderating effects of perceived threat and death anxiety on the relationships between stressors and emotional exhaustion are also examined. METHOD AND RESULTS: Using two survey samples collected from bus and taxi drivers in Taiwan, the results reveal that, except for the effect of time pressure on taxi drivers' exhaustion, job stressors (job overload and time pressure) and economic stressors (job insecurity) positively relate to emotional exhaustion for both bus and taxi drivers. Drivers' emotional exhaustion has negative effects on both job satisfaction and positive effects on risky driving behaviors. Perceived pandemic threat strengthens the positive influence of job insecurity on emotional exhaustion for bus drivers, while perceived pandemic threat and death anxiety weaken the negative influence of job insecurity on emotional exhaustion for taxi drivers. PRACTICAL APPLICATIONS: Effective intervention strategies and policies to mitigate perceived pandemic threat and death anxiety of drivers are recommended.

Rare finding of primary aortoduodenal fistula on single-photon emission computed tomography/computed tomography of gastrointestinal bleeding: A case report.

BACKGROUND: Primary aortoduodenal fistula is a rare cause of gastrointestinal (GI) bleeding consisting of abnormal channels between the aorta and GI tract without previous vascular intervention that results in massive intraluminal hemorrhage. CASE SUMMARY: A 67-year-old man was hospitalized for coffee ground vomiting, tarry stools, and colic abdominal pain. He was repeatedly admitted for active GI bleeding and hypovolemic shock. Intermittent and spontaneously stopped bleeders were undetectable on multiple GI endoscopy, angiography, computed tomography angiography (CTA), capsule endoscopy, and 99mTc-labeled red blood cell (RBC) scans. The patient received supportive treatment and was discharged without signs of rebleeding. Thereafter, he was re-admitted for bleeder identification. Repeated CTA after a bleed revealed a small aortic aneurysm at the renal level contacting the fourth portion of the duodenum. A 99mTc-labeled RBC single-photon emission CT (SPECT)/CT scan performed during bleeding symptoms revealed active bleeding at the duodenal level. According to his clinical symptoms (intermittent massive GI bleeding with hypovolemic shock, dizziness, dark red stool, and bloody vomitus) and the abdominal CTA and 99mTc-labeled RBC SPECT/CT results, we suspected a small aneurysm and an aortoduodenal fistula. Subsequent duodenal excision and duodenojejunal anastomosis were performed. A 7-mm saccular aneurysm arising from the anterior wall of the abdominal aorta near the left renal artery was identified. Percutaneous intravascular stenting of the abdominal aorta was performed and his symptoms improved. CONCLUSION: Our findings suggest that 99mTc-labeled RBC SPECT/CT scanning can aid the diagnosis of a rare cause of active GI bleeding.

Investigating the Effects of Job Stress on the Distraction and Risky Driving Behaviors of Food Delivery Motorcycle Riders.

Background: Occupational safety issues related to food delivery riders emerge with evidence of an increase in associated traffic accidents and injuries along with the rapid growth of the online food delivery business. This paper focuses on food delivery riders' job stress and investigates its relationships with both antecedents and risky riding outcomes. Method: Survey data were collected from 279 Taiwanese food delivery motorcycle riders and analyzed using hierarchical regression analysis. Results: The results show that job overload and time pressure positively impact riders' job stress, while self-efficacy slightly reduces job stress. Job stress positively leads to risky driving behavior and distraction. In addition, time pressure can strengthen the impact of job overload on job stress. Riders' risky riding attitude can also strengthen the impacts of job stress on risky riding behaviors and distraction. Conclusion: This paper advances the literature on online food delivery as well as the occupational safety improvement of food delivery riders. Specifically, this study provides insights into the job stress of food delivery motorcycle riders and the effects of job characteristics and risky behavioral consequences.

Experiences from the international frontlines: An exploration of the perceptions of airport employees during the COVID-19 pandemic.

The aviation industry is one of the sectors that has been heavily impacted by the pandemic. While the major body of literature has focused on passenger experience and behaviour, this study focuses on airport employees instead-their experiences, perceptions, and preferences following the emergence of COVID-19. More than 1000 participants from 4 major airports-Amsterdam Airport Schiphol, Singapore Changi Airport, Taipei Taoyuan Airport, and Zurich Airport-representing over 10 different occupations, have provided a variety of sentiments about the airport as an employment ecosystem in the wake of COVID-19. Quantitatively and qualitatively surveying four different airports enabled a cross-border analysis of the results to identify interesting geographic contrasts, as well as global themes, among the responses. Regional differences regarding, the feeling of preparedness, confidence in measures, and optimism are presented. A significant difference in confidence in non-pharmaceutical measures between employees from Asian and European airports is shown. Wants and needs such as better physical/IT workplace infrastructure and more flexibility regarding job scope and hours are pointed out. The results of this research provide insights for future airport employee experience research by outlining areas to study in greater detail. Furthermore, practical implications for airport stakeholders and companies arising from the challenges experienced by the workforce are laid out to provide guidance to prepare for similar circumstances in the future and navigate the aftermath of and recovery from the pandemic.

The Effects of Personality and Attitude on Risky Driving Behavior Among Public van Drivers: Hierarchical Modeling.

Background: Traffic injuries have become a significant public health problem in low- and middle-income countries. Several studies have examined the role of personality and attitude toward traffic safety in predicting driving behaviors in diverse types of drivers. Few studies have investigated risky behavior among public passenger van drivers. This study aims to identify the predictors of self-reported risky driving behavior among public van drivers. Method: A total of 410 public van drivers were interviewed at terminal stations in Bangkok. Hierarchical regression models were applied to determine the effects of demographics, personality traits, and attitude on self-reported risky driving behaviors. Results: The results indicated that drivers with a high education level, more working days, and high scores for normlessness and anger were more likely to report risky driving behaviors (p < 0.05). Conclusion: The personality traits and attitude toward speeding account for aberrant self-reported risky driving behavior in passenger van drivers. This could be another empirical basis for evidence-based road safety interventions in the context of public transport.

Multilevel analysis of injury severity of elderly motorcycle riders: The role of regional transport development.

OBJECTIVE: Research specifically focusing on the elderly segment of motorcycle riders remains largely scarce, which represents a serious lack in understanding given the fast-growing trend of aging societies around the world. This article examines factors affecting the injury severity of elderly motorcycle riders in Taiwan using a multilevel model consisting of both individual and municipality levels. In particular, this study emphasized the role of municipality-level factors closely related to the municipality characteristics and policy considerations in directing local governments' policies and implementing crash-prevention strategies and measures. METHODS: A multilevel logistic regression model was specified and estimated by using crash data of elderly motorcycle riders across 20 municipalities in Taiwan between 2012 and 2018. Principal component analysis was employed to identify the municipality-level factors. RESULTS: Individual-level factors such as being male, old age, no valid license, drunk driving, not wearing a helmet, turning or overtaking others, early morning and evening riding, errors in traffic signaling, and exceeding the speed limit have significant effects on injury severity. The highlighted municipality-level factor, the transport development index, demonstrates its significant effect on mitigating injury severity across municipalities. CONCLUSIONS: Apart from considering individual factors such as driver-related, vehicle-related and road-side-related variables, this paper shed light on the role of transport development level of a municipality in analyzing the injury severity of elderly motorcycle riders. Policy implications in directing local governments' policies and implementing crash-prevention strategies and measures are discussed and provided.

Highly-efficient electrically-driven localized surface plasmon source enabled by resonant inelastic electron tunneling.

On-chip plasmonic circuitry offers a promising route to meet the ever-increasing requirement for device density and data bandwidth in information processing. As the key building block, electrically-driven nanoscale plasmonic sources such as nanoLEDs, nanolasers, and nanojunctions have attracted intense interest in recent years. Among them, surface plasmon (SP) sources based on inelastic electron tunneling (IET) have been demonstrated as an appealing candidate owing to the ultrafast quantum-mechanical tunneling response and great tunability. However, the major barrier to the demonstrated IET-based SP sources is their low SP excitation efficiency due to the fact that elastic tunneling of electrons is much more efficient than inelastic tunneling. Here, we remove this barrier by introducing resonant inelastic electron tunneling (RIET)-follow a recent theoretical proposal-at the visible/near-infrared (NIR) frequencies and demonstrate highly-efficient electrically-driven SP sources. In our system, RIET is supported by a TiN/Al2O3 metallic quantum well (MQW) heterostructure, while monocrystalline silver nanorods (AgNRs) were used for the SP generation (localized surface plasmons (LSPs)). In principle, this RIET approach can push the external quantum efficiency (EQE) close to unity, opening up a new era of SP sources for not only high-performance plasmonic circuitry, but also advanced optical sensing applications.

Two-Exposure Image Fusion Based on Optimized Adaptive Gamma Correction.

In contrast to conventional digital images, high-dynamic-range (HDR) images have a broader range of intensity between the darkest and brightest regions to capture more details in a scene. Such images are produced by fusing images with different exposure values (EVs) for the same scene. Most existing multi-scale exposure fusion (MEF) algorithms assume that the input images are multi-exposed with small EV intervals. However, thanks to emerging spatially multiplexed exposure technology that can capture an image pair of short and long exposure simultaneously, it is essential to deal with two-exposure image fusion. To bring out more well-exposed contents, we generate a more helpful intermediate virtual image for fusion using the proposed Optimized Adaptive Gamma Correction (OAGC) to have better contrast, saturation, and well-exposedness. Fusing the input images with the enhanced virtual image works well even though both inputs are underexposed or overexposed, which other state-of-the-art fusion methods could not handle. The experimental results show that our method performs favorably against other state-of-the-art image fusion methods in generating high-quality fusion results.

Kerr Metasurface Enabled by Metallic Quantum Wells.

Optical metasurfaces have emerged as promising candidates for multifunctional devices. Dynamically reconfigurable metasurfaces have been introduced by employing phase-change materials or by applying voltage, heat, or strain. While existing metasurfaces exhibit appealing properties, they do not express any significant nonlinear effects due to the negligible nonlinear responses from the typical materials used to build the metasurface. In this work, we propose and experimentally demonstrate one kind of Kerr metasurface that shows strong intensity-dependent responses. The Kerr metasurface is composed of a top layer of gold antennas, a dielectric spacer, and a ground layer of metallic quantum wells (MQWs). Because of the large Kerr nonlinearity supported by the MQWs, the effective optical properties of the MQWs can change from metallic to dielectric with increasing of the input intensity, leading to dramatic modifications of the metasurface responses. This opens up new routes for potential applications in the field of nonlinear optics.

Taking a Closer Look at Bus Driver Emotional Exhaustion and Well-Being: Evidence from Taiwanese Urban Bus Drivers.

BACKGROUND: Urban bus drivers work under conditions that are among the most demanding, stressful, and unhealthy with higher rates of mortality and morbidity as well as absenteeism and turnover. METHODS: Drawing on the job demand-resource model, this study investigates the impacts of job characteristics on emotional exhaustion and the effects of emotional exhaustion on job outcomes (including job satisfaction, life satisfaction, organizational commitment, and turnover intention) in the context of bus drivers. RESULTS: Using self-reported survey data collected from a sample of 320 Taiwanese urban bus drivers, results reveal that role overload and work-family conflict (as job demand factors) positively relate to emotional exhaustion, and organizational support (as a job resource factor) is negatively associated with emotional exhaustion. Emotional exhaustion has negative effects on both job satisfaction and organizational commitment. Job satisfaction positively leads to life satisfaction, whereas organizational commitment negatively relates to turnover intention. CONCLUSION: This study concludes that role overload and work-family conflict as two stressors related to job demands and organizational support as the job resource factor to affect emotional exhaustion which further influence well-being in bus driver context. The moderating effects of both extraversion and neuroticism on the relationship between job demands and emotional exhaustion are evident.

Nanoscale optical pulse limiter enabled by refractory metallic quantum wells.

The past several decades have witnessed rapid development of high-intensity, ultrashort pulse lasers, enabling deeper laboratory investigation of nonlinear optics, plasma physics, and quantum science and technology than previously possible. Naturally, with their increasing use, the risk of accidental damage to optical detection systems rises commensurately. Thus, various optical limiting mechanisms and devices have been proposed. However, restricted by the weak optical nonlinearity of natural materials, state-of-the-art optical limiters rely on bulk liquid or solid media, operating in the transmission mode. Device miniaturization becomes complicated with these designs while maintaining superior integrability and controllability. Here, we demonstrate a reflection-mode pulse limiter (sub-100 nm) using nanoscale refractory films made of Al2O3/TiN/Al2O3 metallic quantum wells (MQWs), which provide large and ultrafast Kerr-type optical nonlinearities due to the quantum size effect of the MQW. Functional multilayers consisting of these MQWs could find important applications in nanophotonics, nonlinear optics, and meta-optics.

Optical edge detection based on high-efficiency dielectric metasurface.

Optical edge detection is a useful method for characterizing boundaries, which is also in the forefront of image processing for object detection. As the field of metamaterials and metasurface is growing fast in an effort to miniaturize optical devices at unprecedented scales, experimental realization of optical edge detection with metamaterials remains a challenge and lags behind theoretical proposals. Here, we propose a mechanism of edge detection based on a Pancharatnam-Berry-phase metasurface. We experimentally demonstrated broadband edge detection using designed dielectric metasurfaces with high optical efficiency. The metasurfaces were fabricated by scanning a focused laser beam inside glass substrate and can be easily integrated with traditional optical components. The proposed edge-detection mechanism may find important applications in image processing, high-contrast microscopy, and real-time object detection on compact optical platforms such as mobile phones and smart cameras.

Large optical nonlinearity enabled by coupled metallic quantum wells.

New materials that exhibit strong second-order optical nonlinearities at a desired operational frequency are of paramount importance for nonlinear optics. Giant second-order susceptibility χ (2) has been obtained in semiconductor quantum wells (QWs). Unfortunately, the limited confining potential in semiconductor QWs causes formidable challenges in scaling such a scheme to the visible/near-infrared (NIR) frequencies for more vital nonlinear-optic applications. Here, we introduce a metal/dielectric heterostructured platform, i.e., TiN/Al2O3 epitaxial multilayers, to overcome that limitation. This platform has an extremely high χ (2) of approximately 1500 pm/V at NIR frequencies. By combining the aforementioned heterostructure with the large electric field enhancement afforded by a nanostructured metasurface, the power efficiency of second harmonic generation (SHG) achieved 10-4 at an incident pulse intensity of 10 GW/cm2, which is an improvement of several orders of magnitude compared to that of previous demonstrations from nonlinear surfaces at similar frequencies. The proposed quantum-engineered heterostructures enable efficient wave mixing at visible/NIR frequencies into ultracompact nonlinear optical devices.

Unraveling the spatiotemporal brain dynamics during a simulated reach-to-eat task.

The reach-to-eat task involves a sequence of action components including looking, reaching, grasping, and feeding. While cortical representations of individual action components have been mapped in human functional magnetic resonance imaging (fMRI) studies, little is known about the continuous spatiotemporal dynamics among these representations during the reach-to-eat task. In a periodic event-related fMRI experiment, subjects were scanned while they reached toward a food image, grasped the virtual food, and brought it to their mouth within each 16-s cycle. Fourier-based analysis of fMRI time series revealed periodic signals and noise distributed across the brain. Independent component analysis was used to remove periodic or aperiodic motion artifacts. Time-frequency analysis was used to analyze the temporal characteristics of periodic signals in each voxel. Circular statistics was then used to estimate mean phase angles of periodic signals and select voxels based on the distribution of phase angles. By sorting mean phase angles across regions, we were able to show the real-time spatiotemporal brain dynamics as continuous traveling waves over the cortical surface. The activation sequence consisted of approximately the following stages: (1) stimulus related activations in occipital and temporal cortices; (2) movement planning related activations in dorsal premotor and superior parietal cortices; (3) reaching related activations in primary sensorimotor cortex and supplementary motor area; (4) grasping related activations in postcentral gyrus and sulcus; (5) feeding related activations in orofacial areas. These results suggest that phase-encoded design and analysis can be used to unravel sequential activations among brain regions during a simulated reach-to-eat task.

Differences in water soluble non-digestible polysaccharides and anti-inflammatory activities of fruiting bodies from two cultivated Xylaria nigripes strains.

Polysaccharides including ß-glucans are important bioactive components of mushroom. Xylaria nigripes is a popular medicinal fungus that has been used for treating trauma, insomnia and mental illness. This study examined the physicochemical characteristics and anti-inflammatory activities of water soluble non-digestible polysaccharides (TXNP and CXNP) from fruiting bodies of two cultivated X. nigripes strains (TXN and CXN). Results showed that both TXNP and CXNP possessed relatively similar FT-IR spectra. TXNP had a triple helix conformation and molecular weight of 853.8 kDa, whereas the molecular weight of CXNP was 14.7 kDa. The monosaccharide composition of TXNP was predominantly glucose, whereas CXNP contained xylose, mannose and glucose. Although both TXNP and CXNP dose-dependently suppressed the production of NO, IL-1ß, TNF-α and PGE2, as well as the expression of iNOS, COX-2 and NF-κB in the lipopolysaccharide-induced RAW264.7 macrophages, the potency of TXNP was stronger. This study reveals that under similar conditions of cultivation and extraction procedures, the different physicochemical characteristics of polysaccharides from TXN and CXN may have contributed to the differences in their anti-inflammatory potency.

Spatiotemporal integration of looming visual and tactile stimuli near the face.

Real-world objects approaching or passing by an observer often generate visual, auditory, and tactile signals with different onsets and durations. Prompt detection and avoidance of an impending threat depend on precise binding of looming signals across modalities. Here we constructed a multisensory apparatus to study the spatiotemporal integration of looming visual and tactile stimuli near the face. In a psychophysical experiment, subjects assessed the subjective synchrony between a looming ball and an air puff delivered to the same side of the face with a varying temporal offset. Multisensory stimuli with similar onset times were perceived as completely out of sync and assessed with the lowest subjective synchrony index (SSI). Across subjects, the SSI peaked at an offset between 800 and 1,000 ms, where the multisensory stimuli were perceived as optimally in sync. In an fMRI experiment, tactile, visual, tactile-visual out-of-sync (TVoS), and tactile-visual in-sync (TViS) stimuli were delivered to either side of the face in randomized events. Group-average statistical responses to different stimuli were compared within each surface-based region of interest (sROI) outlined on the cortical surface. Most sROIs showed a preference for contralateral stimuli and higher responses to multisensory than unisensory stimuli. In several bilateral sROIs, particularly the human MT+ complex and V6A, responses to spatially aligned multisensory stimuli (TVoS) were further enhanced when the stimuli were in-sync (TViS), as expressed by TVoS < TViS. This study demonstrates the perceptual and neural mechanisms of multisensory integration near the face, which has potential applications in the development of multisensory entertainment systems and media.

Anti-Inflammatory Activity and Bioactive Constituents of Cultivated Fruiting Bodies of Xylaria nigripes (Ascomycetes), a Chinese Medicinal Fungus.

Xylaria nigripes, also known as Wu Ling Shen, is popular for treating insomnia and trauma in traditional Chinese medicine. This study aimed to examine the anti-inflammatory activity and bioactive constituents of cultivated X. nigripes fruiting bodies in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. Results showed that among the different extracts, the hexane fraction exhibited the best protection against cell toxicity induced by 1 µg/mL LPS and the strongest inhibitory effect on nitric oxide (NO) production. This fraction led to the isolation of 2 bioactive compounds (namely, XN-CP1 and XN-CP2), which were confirmed to be ergostarien-3ß-ol and ergosterol peroxide, respectively. Although both XN-CP1 and XN-CP2 showed good inhibitory effects on NO, tumor necrosis factor-α, interleukin (IL)-1ß, IL-6, and prostaglandin E2 production in LPS-stimulated macrophages, XN-CP2 was shown to have a stronger anti-inflammatory activity; this was further supported by its strong suppressive effects on inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression and nuclear factor (NF)-κB activation. These results conclude that ergosterol peroxide (XN-CP2) could be the main bioactive compound contributing to the potent anti-inflammatory activity of X. nigripes, and its mechanism of action is mediated through inhibition of iNOS and COX-2 expression via the NF-κB signaling pathway.

Mapping the complex topological organization of the human parietal face area.

The macaque monkey ventral intraparietal area (VIP) contains neurons with aligned visual-tactile receptive fields anchored to the face and upper body. Our previous fMRI studies using standard head coils found a human parietal face area (VIP+ complex; putative macaque VIP homologue) containing superimposed topological maps of the face and near-face visual space. Here, we construct high signal-to-noise surface coils and used phase-encoded air puffs and looming stimuli to map topological organization of the parietal face area at higher resolution. This area is consistently identified as a region extending between the superior postcentral sulcus and the upper bank of the anterior intraparietal sulcus (IPS), avoiding the fundus of IPS. Using smaller voxel sizes, our surface coils picked up strong fMRI signals in response to tactile and visual stimuli. By analyzing tactile and visual maps in our current and previous studies, we constructed a set of topological models illustrating commonalities and differences in map organization across subjects. The most consistent topological feature of the VIP+ complex is a central-anterior upper face (and upper visual field) representation adjoined by lower face (and lower visual field) representations ventrally (laterally) and/or dorsally (medially), potentially forming two subdivisions VIPv (ventral) and VIPd (dorsal). The lower visual field representations typically extend laterally into the anterior IPS to adjoin human area AIP, and medially to overlap with the parietal body areas at the superior parietal ridge. Significant individual variations are then illustrated to provide an accurate and comprehensive view of the topological organization of the parietal face area.

Validation of periodic fMRI signals in response to wearable tactile stimulation.

To map cortical representations of the body, we recently developed a wearable technology for automatic tactile stimulation in human functional magnetic resonance imaging (fMRI) experiments. In a two-condition block design experiment, air puffs were delivered to the face and hands periodically. Surface-based regions of interest (S-ROIs) were initially identified by thresholding a linear statistical measure of signal-to-noise ratio of periodic response. Across subjects, S-ROIs were found in the frontal, primary sensorimotor, posterior parietal, insular, temporal, cingulate, and occipital cortices. To validate and differentiate these S-ROIs, we develop a measure of temporal stability of response based on the assumption that a periodic stimulation evokes stable (low-variance) periodic fMRI signals throughout the entire scan. Toward this end, we apply time-frequency analysis to fMRI time series and use circular statistics to characterize the distribution of phase angles for data selection. We then assess the temporal variability of a periodic signal by measuring the path length of its trajectory in the complex plane. Both within and outside the primary sensorimotor cortex, S-ROIs with high temporal variability and deviant phase angles are rejected. A surface-based probabilistic group-average map is constructed for spatial screening of S-ROIs with low to moderate temporal variability in non-sensorimotor regions. Areas commonly activated across subjects are also summarized in the group-average map. In summary, this study demonstrates that analyzing temporal characteristics of the entire fMRI time series is essential for second-level selection and interpretation of S-ROIs initially defined by an overall linear statistical measure.

Material-assisted metamaterial: a new dimension to create functional metamaterial.

A high Q-value reflective type metasurface consisting of 1D Au nanorods, a SiO2 spacer and a Au back reflector is demonstrated. It is shown that the sideband of the resonant mode can be suppressed as the resonant wavelength close to the phonon absorption of SiO2. By combining both designed structured resonance and inherent property of the based materials, a low angle-dependent metasurface with a Q-value of 40 has been demonstrated. The proposed structure will be useful for high sensitivity sensing and narrow band thermal emitter.