14,738 research outputs found

    Detecting Driver Sleepiness Using Consumer Wearable Devices in Manual and Partial Automated Real-Road Driving

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    Driver sleepiness constitutes a well-known traffic safety risk. With the introduction of automated driving systems, the chance of getting sleepy and even falling asleep at wheel could increase further. Conventional sleepiness detection methods based on driving performance and behavior may not be available under automated driving. Methods based on physiological measurements such as heart rate variability (HRV) becomes a potential solution under automated driving. However, with reduced task load, HRV could potentially be affected by automated driving. Therefore, it is essential to investigate the influence of automated driving on the relation between HRV and sleepiness. Data from real-road driving experiments with 43 participants were used in this study. Each driver finished four trials with manual and partial automated driving under normal and sleep-deprived condition. Heart rate was monitored by consumer wearable chest bands. Subjective sleepiness based on Karolinska sleepiness scale was reported at five min interval as ground truth. Reduced heart rate and increased overall variability were found in association with severe sleepy episodes. A binary classifier based on the AdaBoost method was developed to classify alert and sleepy episodes. The results indicate that partial automated driving has small impact on the relationship between HRV and sleepiness. The classifier using HRV features reached area under curve (AUC) = 0.76 and it was improved to AUC = 0.88 when adding driving time and day/night information. The results show that commercial wearable heart rate monitor has the potential to become a useful tool to assess driver sleepiness under manual and partial automated driving

    Detecting driver fatigue using heart rate variability: A systematic review

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    Driver fatigue detection systems have potential to improve road safety by preventing crashes and saving lives. Conventional driver monitoring systems based on driving performance and facial features may be challenged by the application of automated driving systems. This limitation could potentially be overcome by monitoring systems based on physiological measurements. Heart rate variability (HRV) is a physiological marker of interest for detecting driver fatigue that can be measured during real life driving. This systematic review investigates the relationship between HRV measures and driver fatigue, as well as the performance of HRV based fatigue detection systems. With the applied eligibility criteria, 18 articles were identified in this review. Inconsistent results can be found within the studies that investigated differences of HRV measures between alert and fatigued drivers. For studies that developed HRV based fatigue detection systems, the detection performance showed a large variation, where the detection accuracy ranged from 44% to 100%. The inconsistency and variation of the results can be caused by differences in several key aspects in the study designs. Progress in this field is needed to determine the relationship between HRV and different fatigue causal factors and its connection to driver performance. To be deployed, HRV-based fatigue detection systems need to be thoroughly tested in real life conditions with good coverage of relevant driving scenarios and a sufficient number of participants

    Evidence for a Type-II band alignment between cubic and hexagonal phases of GaN

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    The study of photoluminescence spectra of a series of thin, undoped, hexagonal GaN films containing cubic GaN inclusions grown by molecular-beam epitaxy on 6H-SiC was presented. It was shown that an emission peak at ∼3.17 eV in thin, hexagonal GaN films exhibits behaviors typical of a spatially indirect transition. The values of the band offsets extracted from the data were in good agreement with theoretical predictions.published_or_final_versio

    Exploiting semantic and public prior information in MonoSLAM

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    In this paper, we propose a method to use semantic information to improve the use of map priors in a sparse, feature-based MonoSLAM system. To incorporate the priors, the features in the prior and SLAM maps must be associated with one another. Most existing systems build a map using SLAM and then align it with the prior map. However, this approach assumes that the local map is accurate, and the majority of the features within it can be constrained by the prior. We use the intuition that many prior maps are created to provide semantic information. Therefore, valid associations only exist if the features in the SLAM map arise from the same kind of semantic object as the prior map. Using this intuition, we extend ORB-SLAM2 using an open source pre-trained semantic segmentation network (DeepLabV3+) to incorporate prior information from Open Street Map building footprint data. We show that the amount of drift, before loop closing, is significantly smaller than that for original ORB-SLAM2. Furthermore, we show that when ORB-SLAM2 is used as a prior-aided visual odometry system, the tracking accuracy is equal to or better than the full ORB-SLAM2 system without the need for global mapping or loop closure

    Atoms in Flight and the Remarkable Connections between Atomic and Hadronic Physics

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    Atomic physics and hadron physics are both based on Yang Mills gauge theory; in fact, quantum electrodynamics can be regarded as the zero-color limit of quantum chromodynamics. I review a number of areas where the techniques of atomic physics provide important insight into the theory of hadrons in QCD. For example, the Dirac-Coulomb equation, which predicts the spectroscopy and structure of hydrogenic atoms, has an analog in hadron physics in the form of light-front relativistic equations of motion which give a remarkable first approximation to the spectroscopy, dynamics, and structure of light hadrons. The renormalization scale for the running coupling, which is unambiguously set in QED, leads to a method for setting the renormalization scale in QCD. The production of atoms in flight provides a method for computing the formation of hadrons at the amplitude level. Conversely, many techniques which have been developed for hadron physics, such as scaling laws, evolution equations, and light-front quantization have equal utility for atomic physics, especially in the relativistic domain. I also present a new perspective for understanding the contributions to the cosmological constant from QED and QCD.Comment: Presented at EXA2011, the International Conference on Exotic Atoms and Related Topics, Vienna, September 5-9, 201

    Dysbiosis of intestinal microbiota mediates tubulointerstitial injury in diabetic nephropathy via the disruption of cholesterol homeostasis

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    BACKGROUND: Our previous study demonstrated that the disruption of cholesterol homeostasis promotes tubulointerstitial injury in diabetic nephropathy (DN). This study aimed to further investigate the effects of gut microbiota dysbiosis on this process and explored its potential mechanism. METHODS: Diabetic rats treated with broad-spectrum oral antibiotics or faecal microbiota transplantation (FMT) from the healthy donor group and human kidney 2 (HK-2) cells stimulated with sodium acetate were used to observe the effects of gut microbiota on cholesterol homeostasis. The gut microbiota distribution was measured by 16S rDNA sequencing with faeces. Serum acetate level was examined by gas chromatographic analysis. Protein expression of G protein coupled receptor 43 (GPR43) and molecules involved in cholesterol homeostasis were assessed by immunohistochemical staining, immunofluorescence staining, and Western Blotting. RESULTS: Depletion of gut microbiota significantly attenuated albuminuria and tubulointerstitial injury. Interestingly, serum acetate levels were also markedly decreased in antibiotics-treated diabetic rats and positively correlated with the cholesterol contents in kidneys. An in vitro study demonstrated that acetate significantly increased cholesterol accumulation in HK-2 cells, which was caused by increased expression of proteins mainly modulating cholesterol synthesis and uptake. As expected, FMT effectively decreased serum acetate levels and alleviated tubulointerstitial injury in diabetic rats through overriding the disruption of cholesterol homeostasis. Furthermore, GPR43 siRNA treatment blocked acetate-mediated cholesterol homeostasis dysregulation in HK-2 cells through decreasing the expression of proteins governed cholesterol synthesis and uptake. CONCLUSIONS: Our studies for the first time demonstrated that the acetate produced from gut microbiota mediated the dysregulation of cholesterol homeostasis through the activation of GPR43, thereby contributing to the tubulointerstitial injury of DN, suggesting that gut microbiota reprogramming might be a new strategy for DN prevention and therapy

    Violet electroluminescence of AlInGaN-InGaN multiquantum-well light-emitting diodes: Quantum-confined stark effect and heating effect

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    Electroluminescence (EL) from AlInGaN-InGaN multiquantum-well violet light-emitting diodes is investigated as a function of forward bias. Two distinct regimes have been identified: 1) quantum-confined Stark effect at low and moderately high forward biases; 2) heating effect at high biases. In the different regimes, the low-temperature EL spectra exhibit different spectral features which are discussed in detail. © 2007 IEEE.published_or_final_versio

    Beliefs about the Minds of Others Influence How We Process Sensory Information

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    Attending where others gaze is one of the most fundamental mechanisms of social cognition. The present study is the first to examine the impact of the attribution of mind to others on gaze-guided attentional orienting and its ERP correlates. Using a paradigm in which attention was guided to a location by the gaze of a centrally presented face, we manipulated participants' beliefs about the gazer: gaze behavior was believed to result either from operations of a mind or from a machine. In Experiment 1, beliefs were manipulated by cue identity (human or robot), while in Experiment 2, cue identity (robot) remained identical across conditions and beliefs were manipulated solely via instruction, which was irrelevant to the task. ERP results and behavior showed that participants' attention was guided by gaze only when gaze was believed to be controlled by a human. Specifically, the P1 was more enhanced for validly, relative to invalidly, cued targets only when participants believed the gaze behavior was the result of a mind, rather than of a machine. This shows that sensory gain control can be influenced by higher-order (task-irrelevant) beliefs about the observed scene. We propose a new interdisciplinary model of social attention, which integrates ideas from cognitive and social neuroscience, as well as philosophy in order to provide a framework for understanding a crucial aspect of how humans' beliefs about the observed scene influence sensory processing

    Cancer-related pain in head and neck cancer survivors: longitudinal findings from the Head and Neck 5000 clinical cohort

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    \ua9 The Author(s) 2024.Purpose: Reports suggest pain is common in head and neck cancer (HNC). However, past studies are limited by small sample sizes and design and measurement heterogeneity. Using data from the Head and Neck 5000 longitudinal cohort, we investigated pain over a year post-diagnosis. We assessed: temporal trends; compared pain across HNC treatments, stages, sites and by HPV status; and identified subgroups of patients at increased risk of pain. Methods: Sociodemographic and clinical data and patient-reported pain (measured by EORTC QLQ-C30 and QLQ-H&N35) were collected at baseline (pre-treatment), 4- and 12- months. Using mixed effects multivariable regression, we investigated time trends and identified associations between (i) clinically-important general pain and (ii) HN-specific pain and clinical, socio-economic, and demographic variables. Results: 2,870 patients were included. At baseline, 40.9% had clinically-important general pain, rising to 47.6% at 4-months and declining to 35.5% at 12-months. HN-specific pain followed a similar pattern (mean score (sd): baseline 26.4 (25.10); 4-months. 28.9 (26.55); 12-months, 17.2 (19.83)). Across time, general and HN-specific pain levels were increased in: younger patients, smokers, and those with depression and comorbidities at baseline, and more advanced, oral cavity and HPV negative cancers. Conclusions: There is high prevalence of general pain in people living with HNC. We identified subgroups more often reporting general and HN-specific pain towards whom interventions could be targeted. Implications for cancer survivors: Greater emphasis should be placed on identifying and treating pain in HNC. Systematic pain screening could help identify those who could benefit from an early pain management plan
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