Is the disappearance of the cervical flexion-relaxation phenomenon associated with cervical degeneration in healthy people?

PURPOSE: This study aims to explore the differences in cervical degeneration between healthy people with and without cervical flexion-relaxation phenomenon (FRP) and to identify whether the disappearance of cervical FRP is related to cervical degeneration. METHODS: According to the flexion relaxation ratio (FRR), healthy subjects were divided into the normal FRP group and the abnormal FRP group. Besides, MRI was used to evaluate the degeneration of the passive subsystem (vertebral body, intervertebral disc, cervical sagittal balance, etc.) and the active subsystem (deep flexors [DEs], deep extensors [DFs], and superficial extensors [SEs]). In addition, the correlation of the FRR with the cervical degeneration score, C2-7Cobb, Borden method, relative total cross-sectional area (rTCSA), relative functional cross-sectional area (rFCSA), and fatty infiltration ratio (FIR) was analyzed. RESULTS: A total of 128 healthy subjects were divided into the normal FRP group (n=52, 40.63%) and the abnormal FRP group (n=76, 59.38%). There were significant differences between the normal FRP group and the abnormal FRP group in the cervical degeneration score (z=-6.819, P<0.001), C2-7Cobb (t=2.994, P=0.004), Borden method (t=2.811, P=0.006), and FIR of DEs (t=-4.322, P<0.001). The FRR was significantly correlated with the cervical degeneration score (r=-0.457, P<0.001), C2-7Cobb (r=0.228, P=0.010), Borden method (r=0.197, P=0.026), and FIR of DEs (r=-0.253, P=0.004). CONCLUSION: The disappearance of cervical FRP is related to cervical degeneration. A new hypothesis mechanism for FRP is proposed. The cervical FRP test is an effective and noninvasive examination for the differential diagnosis of healthy people, people with potential NSNP, and patients with NSNP.

A Vibration Analysis for the Evaluation of Fuel Rail Pressure and Mass Air Flow Sensors on a Diesel Engine: Strategies for Predictive Maintenance.

This research focuses on the analysis of vibration of a compression ignition engine (CIE), specifically examining potential failures in the Fuel Rail Pressure (FRP) and Mass Air Flow (MAF) sensors, which are critical to combustion control. In line with current trends in mechanical system condition monitoring, we are incorporating information from these sensors to monitor engine health. This research proposes a method to validate the correct functioning of these sensors by analysing vibration signals from the engine. The effectiveness of the proposal is confirmed using real data from a Common Rail Direct Injection (CRDi) engine. Simulations using a GT 508 pressure simulator mimic FRP sensor failures and an adjustable potentiometer manipulates the MAF sensor signal. Vibration data from the engine are processed in MATLAB using frequency domain techniques to investigate the vibration response. The results show that the proposal provides a basis for an efficient predictive maintenance strategy for the MEC engine. The early detection of FRP and MAF sensor problems through a vibration analysis improves engine performance and reliability, minimizing downtime and repair costs. This research contributes to the advancement of monitoring and diagnostic techniques in mechanical engines, thereby improving their efficiency and durability.

Sustainable repurpose of end-of-life fiber reinforced polymer composites: A new circular pedestrian bridge concept.

In response to global challenges in resource supply, many industries are adopting the principles of the Circular Economy (CE) to improve their resource acquisition strategies. This paper introduces an innovative approach to address the environmental impact of waste Glass Fiber Reinforced-Polymer (GFRP) pipes and panels by repurposing them to manufacture structural components for new bicycle and pedestrian bridges. The study covers the entire process, including conceptualization, analysis, design, and testing of a deck system, with a focus on the manufacturing process for a 7-m-long prototype bridge. The study shows promising results in the concept of a sandwich structure utilizing discarded GFRP pipes and panels, which has the flexibility to account for variabilities in dimensions of incoming products while still meeting mechanical requirements. The LCA analysis shows that the transportation of materials is the governing contributing factor. It was concluded that further development of this concept should be accompanied by a business model that considers the importance of the contributions from the whole value chain.

Fuel-Type Independent Parameterization of Volatile Organic Compound Emissions from Western US Wildfires.

Volatile organic compounds (VOCs) emitted from biomass burning impact air quality and climate. Laboratory studies have shown that the variability in VOC speciation is largely driven by changes in combustion conditions and is only modestly impacted by fuel type. Here, we report that emissions of VOCs measured in ambient smoke emitted from western US wildfires can be parameterized by high- and low-temperature pyrolysis VOC profiles and are consistent with previous observations from laboratory simulated fires. This is demonstrated using positive matrix factorization (PMF) constrained by high- and low-temperature factors using VOC measurements obtained with a proton-transfer reaction time-of-flight mass spectrometer (PTR-ToF-MS) on board the NASA DC-8 during the FIREX-AQ (Fire Influence on Regional and Global Environments and Air Quality) project in 2019. A linear combination of high- and low-temperature factors described more than 70% of the variability of VOC emissions of long-lived VOCs in all sampled wildfire plumes. An additional factor attributable to atmospheric aging was required to parameterize short-lived and secondarily produced VOCs. The relative contribution of the PMF-derived high-temperature factor for a given fire plume was strongly correlated with the fire radiative power (FRP) at the estimated time of emission detected by satellite measurements. By combining the FRP with the fraction of the high-temperature PMF factor, the emission ratios (ERs) of VOCs to carbon monoxide (CO) in fresh wildfires were estimated and agree well with measured ERs (r2 = 0.80-0.93).

Characterization of global fire activity and its spatiotemporal patterns for different land cover types from 2001 to 2020.

Fire is a widespread phenomenon that plays an important role in Earth's ecosystems. This study investigated the global spatiotemporal patterns of burned areas, daytime and nighttime fire counts, and fire radiative power (FRP) from 2001 to 2020. The month with the largest burned area, daytime fire count, and FRP presented a bimodal distribution worldwide, with dual peaks in early spring (April) and summer (July and August), while the month with the largest nighttime fire count and FRP showed a unimodal distribution, with a peak in July. Although the burned area showed decline at the global scale, a significant increase occurred in temperate and boreal forest regions, where nighttime fire occurrence and intensity have consistently increased in recent years. The relationships among burned area, fire count, and FRP were further quantified in 12 typical fire-prone regions. The burned area and fire count exhibited a humped relationship with FRP in most tropical regions, whereas the burned area and fire count constantly increased when the FRP was below approximately 220 MW in temperate and boreal forest regions. Meanwhile, the burned area and FRP generally increased with the fire count in most fire-prone regions, indicating an increased risk of more intense and larger fires as the fire count increased. The spatiotemporal dynamics of burned areas for different land cover types were also explored in this study. The results suggest that the burned areas in forest, grassland, and cropland showed dual peaks in April and from July to September while the burned areas in shrubland, bareland, and wetlands usually peaked in July or August. Significant increases in forest burned area were observed in temperate and boreal forest regions, especially in the western U.S. and Siberia, whereas significant increases in cropland burned area were found in India and northeastern China.

Wireless, Material-Integrated Sensors for Strain and Temperature Measurement in Glass Fibre Reinforced Composites.

Fiber reinforced plastics (FRP) offer huge potentials for energy efficient applications. Special care must be taken during both FRP fabrication and usage to ensure intended material properties and behavior. This paper presents a novel approach for the monitoring of the strain and temperature of glass fibre reinforced polymer (GFRP) materials in the context of both production process monitoring and structural health monitoring (SHM) applications. The sensor is designed to be integrated into GFRPs during the production process, and the sensor concept includes possibilities of automated placement during textile layup. To minimize sensor impact on GFRP integrity and to simplify vacuum setup and part handling, the sensor operates without the need for either wires or a battery. In the first sections of this work, sensor concept, design and prototype fabrication are presented. Subsequently, it is shown how the sensors can be used for flow front monitoring and cure estimation during GFRP production by measuring local resin temperature. The resulting specimens are then characterized regarding strain measurement capabilities, mechanical influence on the host component and overall system limitations. Average strain sensor accuracy is found to be ≤0.06 mm/m, while a maximum operation temperature of 126.9 °C and a maximum reading distance of 38 mm are measured. Based on a limited number of bending tests, no negative influence of sensor presence on breaking strength could be found. Possible applications include structural components, e.g., wind turbine blades or boat hulls.

Analysis of FRP-Strengthened Reinforced Concrete Beams Using Electromechanical Impedance Technique and Digital Image Correlation System.

Fiber-reinforced polymer (FRP) strengthening systems have been considered an effective technique to retrofit concrete structures, and their use nowadays is more and more extensive. Externally bonded reinforcement (EBR) and near-surface mounted (NSM) technologies are the two most widely recognized and applied FRP strengthening methods for enhancing structural performance worldwide. However, one of the main disadvantages of both approaches is a possible brittle failure mode provided by a sudden debonding of the FRP. Therefore, methodologies able to monitor the long-term efficiency of this kind of strengthening constitute a challenge to be overcome. In this work, two reinforced concrete (RC) specimens strengthened with FRP and subjected to increasing load tests were monitored. One specimen was strengthened using the EBR method, while for the other, the NSM technique was used. The multiple cracks emanating in both specimens in the static tests, as possible origins of a future debonding failure, were monitored using a piezoelectric (PZT)-transducer-based electromechanical impedance (EMI) technique and a digital image correlation (DIC) system. Clustering approaches based on impedance measurements of the healthy and damaged states of the specimens allowed us to suspect the occurrence of cracks and their growth. The strain profiles captured in the images of the DIC system allowed us to depict surface hair-line cracks and their propagation. The combined implementation of the two techniques to look for correlations during incremental bending tests was addressed in this study as a means of improving the prediction of early cracks and potentially anticipating the complete failure of the strengthened specimens.

Experimental Study on Monitoring Damage Progression of Basalt-FRP Reinforced Concrete Slabs Using Acoustic Emission and Machine Learning.

Basalt fiber-reinforced polymer (BFRP) reinforced concrete is a new alternative to conventional steel-reinforced concrete due to its high tensile strength and corrosion resistance characteristics. However, as BFRP is a brittle material, unexpected failure of concrete structures reinforced with BFRP may occur. In this study, the damage initiation and progression of BFRP-reinforced concrete slabs were monitored using the acoustic emission (AE) method as a structural health monitoring (SHM) solution. Two simply supported slabs were instrumented with an array of AE sensors in addition to a high-resolution camera, strain, and displacement sensors and then loaded until failure. The dominant damage mechanism was concrete cracking due to the over-reinforced design and adequate BFRP bar-concrete bonding. The AE method was evaluated in terms of identifying the damage initiation, progression from tensile to shear cracks, and the evolution of crack width. Unsupervised machine learning was applied to the AE data obtained from the first slab testing to develop the clusters of the damage mechanisms. The cluster results were validated using the k-means supervised learning model applied to the data obtained from the second slab. The accuracy of the K-NN model trained on the first slab was 99.2% in predicting three clusters (tensile crack, shear crack, and noise). Due to the limitation of a single indicator to characterize complex damage properties, a Statistical SHapley Additive exPlanation (SHAP) analysis was conducted to quantify the contribution of each AE feature to crack width. Based on the SHAP analysis, the AE duration had the highest correlation with the crack width. The cumulative duration of the AE sensor near the crack had close to 100% accuracy to track the crack width. It was concluded that the AE sensors positioned at the mid-span of slabs can be used as an effective SHM solution to monitor the initiation of tensile cracks, sudden changes in structural response due to major damage, damage evolution from tensile to shear cracks, and the progression of crack width.

An Approach for Easy Detection of Buried FRP Composite/Non-Metallic Pipes Using Ground-Penetrating Radar.

Pipelines remain the safest means of transporting natural gas and petroleum products. Nonetheless, the pipeline infrastructure in the US is facing major challenges, especially in terms of corrosion of steel/metallic pipes and excavation damage of onshore pipelines (leading to oil spills, explosions, and deaths). Corrosion of metallic pipelines can be avoided by using non-corrosive materials such as plastic pipes for low-pressure applications and glass-fiber-reinforced polymer (GFRP) composite pipes for transporting high-pressure oil and natural gas. However, buried non-metallic pipelines are not easily detectable, which can lead to increased excavation damage during construction and rehabilitation work. Alternative strategies for making buried non-metallic pipes easily locatable using ground-penetrating radar (GPR) were investigated in this study. Results from this study have shown that using carbon fabric or an aluminum foil overlay on non-metallic pipes before burying in soil significantly increases the reflected GPR signal amplitude, thereby making it easier to locate such pipelines. The reflected GPR signal amplitude for pipe sections with carbon fabric or aluminum foil overlays was found to have increased by a factor of up to 4.5 over the control samples. The results also highlight the importance of selecting the appropriate antenna frequency for GPR surveys, since wet silt loam soil and clay significantly reduce the penetration depths of the radar signals produced by the GPR antennae.

Efficacy and Damage Diagnosis of Reinforced Concrete Columns and Joints Strengthened with FRP Ropes Using Piezoelectric Transducers.

Recent research has indicated that the implantation of a network of piezoelectric transducer patches in element regions of potential damage development, such as the beam-column joint (BCJ) area, substantially increases the efficacy and accuracy of the structural health monitoring (SHM) methods to identify damage level, providing a reliable diagnosis. The use of piezoelectric lead zirconate titanate (PZT) transducers for the examination of the efficiency of an innovative strengthening technique of reinforced concrete (RC) columns and BCJs is presented and commented on. Two real-scale RC BCJ subassemblages were constructed for this investigation. The columns and the joint panel of the second subassemblage were externally strengthened with carbon fiber-reinforced polymer (C-FRP) ropes. To examine the efficiency of this strengthening technique we used the following transducers: (a) PZT sensors on the ropes and the concrete; (b) tSring linear variable displacement transducers (SLVDTs), diagonally installed on the BCJ, to measure the shear deformations of the BCJ panel; (c) Strain gauges on the internal steel bars. From the experimental results, it became apparent that the PZT transducers successfully diagnosed the loading step at which the primary damage occurred in the first BCJ subassemblage and the damage state of the strengthened BCJ during the loading procedure. Further, data acquired from the diagonal SLVDTs and the strain gauges provided insight into the damage state of the two tested specimens at each step of the loading procedure and confirmed the diagnosis provided by the PZT transducers. Furthermore, data acquired by the PZT transducers, SLVDTs and strain gauges proved the effectiveness of the applied strengthening technique with C-FRP ropes externally mounted on the column and the conjunction area of the examined BCJ subassemblages.

Ergonomic exposures and control measures associated with mass fatality decedent handling in morgues and body collection points in a New York healthcare system during COVID-19: A case series.

INTRODUCTION: In April 2020, novel coronavirus SARS-CoV-2 (COVID-19) produced an ongoing mass fatality event in New York. This overwhelmed hospital morgues necessitating emergent expansion of capacity in the form of refrigerated trucks, trailers, and shipping containers referred to as body collection points (BCPs). The risks for musculoskeletal injury during routine and mass fatality mortuary operations and experiences of decedent handlers throughout the "first wave" of COVID-19 are presented along with mitigation strategies. METHODS: Awareness of the high rates of musculoskeletal injury among health care workers due to ergonomic exposures from patient handling, including heavy and repetitive manual lifting, prompted safety walkthroughs of mortuary operations at multiple hospitals within a health system in New York State by workforce safety specialists. Site visits sought to identify ergonomic exposures and ameliorate risk for injury associated with decedent handling by implementing engineering, work practice, and administrative controls. RESULTS: Musculoskeletal exposures included manual lifting of decedents to high and low surfaces, non-neutral postures, maneuvering of heavy equipment, and push/pull forces associated with the transport of decedents. DISCUSSION: Risk mitigation strategies through participatory ergonomics, education on body mechanics, development of novel handling techniques implementing friction-reducing aides, procurement of specialized equipment, optimizing BCP design, and facilitation of communication between hospital and system-wide departments are presented along with lessons learned. After-action review of health system workers' compensation data found over four thousand lost workdays due to decedent handling related incidents, which illuminates the magnitude of musculoskeletal injury risk to decedent handlers.

Progress in the Free and Controlled Radical Homo- and Co-Polymerization of Itaconic Acid Derivatives: Toward Functional Polymers with Controlled Molar Mass Distribution and Architecture.

Polymeric derivatives of itaconic acid are becoming increasingly more interesting for research and industry because itaconic acid is accessible from renewable resources. In spite of the structural similarity of poly(itaconic acid derivatives) to poly(methacrylates), they are much less reactive, homopolymerize only sluggishly by free radical polymerization (FRP), and are often obtained with low molar masses and conversions. This has so far limited their use. The reasons for the low reactivity of itaconic acid derivatives (including itaconimides, diitaconates, and diitaconamides) are combined steric and electronic effects, as demonstrated by the body of literature on the FRP homopolymerization kinetics of these monomers which is summarized herein. These problems can be solved to a large extent by using controlled radical polymerization (CRP) techniques, notably atom transfer radical polymerization (ATRP) and reversible addition and fragmentation chain transfer radical polymerization (RAFT). By optimizing the reaction conditions for the ATRP and RAFT of itaconic acid derivatives, in particular the reaction temperature, linear relations between molar mass and conversion are obtained in many cases, and homopolymers with high molar masses and reasonably narrow polydispersity indices become accessible. This review presents the state-of-the-art FRP and CRP of itaconic acid derivatives, and highlights functional polymers obtained by these methods.

Impaired Fixation-Related Theta Modulation Predicts Reduced Visual Span and Guided Search Deficits in Schizophrenia.

During normal visual behavior, individuals scan the environment through a series of saccades and fixations. At each fixation, the phase of ongoing rhythmic neural oscillations is reset, thereby increasing efficiency of subsequent visual processing. This phase-reset is reflected in the generation of a fixation-related potential (FRP). Here, we evaluate the integrity of theta phase-reset/FRP generation and Guided Visual Search task in schizophrenia. Subjects performed serial and parallel versions of the task. An initial study (15 healthy controls (HC)/15 schizophrenia patients (SCZ)) investigated behavioral performance parametrically across stimulus features and set-sizes. A subsequent study (25-HC/25-SCZ) evaluated integrity of search-related FRP generation relative to search performance and evaluated visual span size as an index of parafoveal processing. Search times were significantly increased for patients versus controls across all conditions. Furthermore, significantly, deficits were observed for fixation-related theta phase-reset across conditions, that fully predicted impaired reduced visual span and search performance and correlated with impaired visual components of neurocognitive processing. By contrast, overall search strategy was similar between groups. Deficits in theta phase-reset mechanisms are increasingly documented across sensory modalities in schizophrenia. Here, we demonstrate that deficits in fixation-related theta phase-reset during naturalistic visual processing underlie impaired efficiency of early visual function in schizophrenia.

A Bi-Spectral Microbolometer Sensor for Wildfire Measurement.

This study describes the development of a prototype bi-spectral microbolometer sensor system designed explicitly for radiometric measurement and characterization of wildfire mid- and long-wave infrared radiances. The system is tested experimentally over moderate-scale experimental burns coincident with FLIR reference imagery. Statistical comparison of the fire radiative power (FRP; W) retrievals suggest that this novel system is highly reliable for use in collecting radiometric measurements of biomass burning. As such, this study provides clear experimental evidence that mid-wave infrared microbolometers are capable of collecting FRP measurements. Furthermore, given the low resource nature of this detector type, it presents a suitable option for monitoring wildfire behaviour from low resource platforms such as unmanned aerial vehicles (UAVs) or nanosats.

Performance of Linear Mixed Models to Assess the Effect of Sustained Loading and Variable Temperature on Concrete Beams Strengthened with NSM-FRP.

Although some extended studies about the short-term behavior of NSM FRP strengthened beams have been carried out, there is a lack of knowledge about the behavior of this kind of strengthening under sustained loads and high service temperatures. Electromechanical impedance method formulated from measurements obtained from PZT patches gives the ability for monitoring the performance and changes experienced by these strengthened beams at a local level, which is a key aspect considering its possible premature debonding failure modes. This paper presents an experimental testing program aimed at investigating the long-term performance of a concrete beam strengthened with a NSM CFRP laminate. Long term performance under different levels of sustained loading and temperature conditions is correlated with EMI signatures processed using Linear Mixed-effects models. These models are very powerful to process datasets that have a multilevel or hierarchical structure as those yielded by our tests. Results have demonstrated the potential of these techniques as health monitoring methodology under different conditions in an especially complex problem such as NSM-FRP strengthened concrete structures.

Protection and Installation of FBG Strain Sensor in Deep Boreholes for Subsurface Faults Behavior Monitoring.

Fiber optic sensors are gradually replacing electrical sensors in geotechnical applications owing to their immunity to electrical interference, durability, and cost-effectiveness. However, additional protective measures are required to prevent loss of functionality due to damage to the sensors, cables, or connection parts (splices and/or connectors) during installation and completion processes in borehole applications. We introduce two cases of installing fiber Bragg grating (FBG) strain sensors in 1 km boreholes to monitor the behavior of deep subsurface faults. We present our fiber-reinforced plastic (FRP) forming schemes to protect sensors and splices. We also present uniaxial load test and post-completion monitoring results for assessing the effects and performance of the protective measures. The uniaxial load test and post-completion monitoring show that FBG sensors are well protected by FRP forming without significant impact on sensor performance itself and that they are successfully installed in deep boreholes. In addition to summarizing our learning from experiences, we also suggest several points for consideration to improve the applicability of FBG sensors in borehole environment of the geotechnical field.

Analysis of the Impact of Sustained Load and Temperature on the Performance of the Electromechanical Impedance Technique through Multilevel Machine Learning and FBG Sensors.

The electro-mechanical impedance (EMI) technique has been applied successfully to detect minor damage in engineering structures including reinforced concrete (RC). However, in the presence of temperature variations, it can cause false alarms in structural health monitoring (SHM) applications. This paper has developed an innovative approach that integrates the EMI methodology with multilevel hierarchical machine learning techniques and the use of fiber Bragg grating (FBG) temperature and strain sensors to evaluate the mechanical performance of RC beams strengthened with near surface mounted (NSM)-fiber reinforced polymer (FRP) under sustained load and varied temperatures. This problem is a real challenge since the bond behavior at the concrete-FRP interface plays a key role in the performance of this type of structure, and additionally, its failure occurs in a brittle and sudden way. The method was validated in a specimen tested over a period of 1.5 years under different conditions of sustained load and temperature. The analysis of the experimental results in an especially complex problem with the proposed approach demonstrated its effectiveness as an SHM method in a combined EMI-FBG framework.

Optimizing the ICA-based removal of ocular EEG artifacts from free viewing experiments.

Combining EEG with eye-tracking is a promising approach to study neural correlates of natural vision, but the resulting recordings are also heavily contaminated by activity of the eye balls, eye lids, and extraocular muscles. While Independent Component Analysis (ICA) is commonly used to suppress these ocular artifacts, its performance under free viewing conditions has not been systematically evaluated and many published reports contain residual artifacts. Here I evaluated and optimized ICA-based correction for two tasks with unconstrained eye movements: visual search in images and sentence reading. In a first step, four parameters of the ICA pipeline were varied orthogonally: the (1) high-pass and (2) low-pass filter applied to the training data, (3) the proportion of training data containing myogenic saccadic spike potentials (SP), and (4) the threshold for eye tracker-based component rejection. In a second step, the eye-tracker was used to objectively quantify the correction quality of each ICA solution, both in terms of undercorrection (residual artifacts) and overcorrection (removal of neurogenic activity). As a benchmark, results were compared to those obtained with an alternative spatial filter, Multiple Source Eye Correction (MSEC). With commonly used settings, Infomax ICA not only left artifacts in the data, but also distorted neurogenic activity during eye movement-free intervals. However, correction results could be strongly improved by training the ICA on optimally filtered data in which SPs were massively overweighted. With optimized procedures, ICA removed virtually all artifacts, including the SP and its associated spectral broadband artifact from both viewing paradigms, with little distortion of neural activity. It also outperformed MSEC in terms of SP correction. Matlab code is provided.

Face Selective Neural Activity: Comparisons Between Fixed and Free Viewing.

Event Related Potentials (ERPs) are widely used to study category-selective EEG responses to visual stimuli, such as the face-selective N170 component. Typically, this is done by flashing stimuli at the point of static gaze fixation. While allowing for good experimental control, these paradigms ignore the dynamic role of eye-movements in natural vision. Fixation-related potentials (FRPs), obtained using simultaneous EEG and eye-tracking, overcome this limitation. Various studies have used FRPs to study processes such as lexical processing, target detection and attention allocation. The goal of this study was to carefully compare face-sensitive activity time-locked to an abrupt stimulus onset at fixation, with that time-locked to a self-generated fixation on a stimulus. Twelve participants participated in three experimental conditions: Free-viewing (FRPs), Cued-viewing (FRPs) and Control (ERPs). We used a multiple regression approach to disentangle overlapping activity components. Our results show that the N170 face-effect is evident for the first fixation on a stimulus, whether it follows a self-generated saccade or stimulus appearance at fixation point. The N170 face-effect has similar topography across viewing conditions, but there were major differences within each stimulus category. We ascribe these differences to an overlap of the fixation-related lambda response and the N170. We tested the plausibility of this account using dipole simulations. Finally, the N170 exhibits category-specific adaptation in free viewing. This study establishes the comparability of the free-viewing N170 face-effect with the classic event-related effect, while highlighting the importance of accounting for eye-movement related effects.

Metagenomic insights into the changes in microbial community and antimicrobial resistance genes associated with different salt content of red pepper (Capsicum annuum L.) sauce.

Fermented red pepper (FRP) sauce has been eaten in worldwide for many years. The salt content and resident microbial community influences the quality of the FRP sauce and may confer health (e.g., probiotics) or harm (e.g., antibiotic resistance genes) to the consumers in some circumstances; however, the salt-mediated alteration of microbial community and antibiotic resistance genes are little known. In this study, a combination of whole genome sequencing and amplicon analysis was used to investigate the changes in microbial community and antimicrobial resistance genes in response to different salt content during red pepper fermentation. While the family Enterobacteriaceae dominated in high-salt (15-25%) samples, Lactobacillaceae quickly became the dominant population in place of Enterobacteriaceae after 24 days in 10% salt samples. Compared to 0.05 antibiotic resistance genes (ARGs) per cell number on average in 10% salt sample, 16.6 ARGs were present in high-salt samples, wherein the bacterial hosts were major assigned to Enterobacteriaceae including genera Enterobacter, Citrobacter, Escherichia, Salmonella and Klebsiella. Multidrug resistance genes were the predominant ARG type. Functional profiling showed that histidine kinase functions were of much higher abundance in high-salt samples and included several osmotic stress-related two-component systems that simultaneously encoded ARGs. These results give first metagenomic insights into the salt-mediated changes in microbial community composition and a broad view of associated antibiotic resistance genes in the process of food fermentation.