RESUMEN

Hydrothermal liquefaction aqueous phase (HTL-AP) is a waste product from a thermochemical process where wet biomass is converted into biocrude oil. This nutrient-rich wastewater may be repurposed to benefit society by assisting crop growth after adequate treatment to increase inorganic nitrogen, especially NO3 -. This study aims to increase HTL-AP inorganic nitrogen, specifically NH3/NH4 + and NO3 -, through fungal remediation for further use in hydroponic systems. Trametes versicolor, a white-rot fungus known for degrading a range of organic pollutants, was used to treat a diluted (5 %) HTL-AP for 9 days. No fungal growth was observed, but T. versicolor activity was suspected by laccase activity throughout cultivation time. NO3 --N and NH3/NH4 +-N increased by 17 and 8 times after three days of fungal treatment, which was chosen as the appropriate time for HTL-AP fungal treatment as it resulted in the highest concentration of NO3 --N. The addition of nitrifying bacteria to the fungal treatment resulted in a twofold increase in NO3 --N concentration compared to the fungal treatment alone, indicating an enhancement in treatment efficacy. COD decreased by 51.33 % after 24 h, which may be related to the fungus' capacity to reduce the concentration of organics in the wastewater; nonetheless, COD increased in the following days, which may be related to the release of fungal byproducts. T. versicolor shows promise as a potential candidate for increasing inorganic nitrogen in HTL-AP. However, future studies should primarily address HTL-AP toxicity, reducing NH3/NH4 +-N while increasing NO3 --N, and hydroponics crop production after fungal treatment.

RESUMEN

This joint ASGE-ESGE guideline provides an evidence-based summary and recommendations regarding the role of endoscopic bariatric and metabolic therapies (EBMTs) in the management of obesity. The document was developed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework. It evaluates the efficacy and safety of EBMT devices and procedures that currently have CE mark or FDA-clearance/approval, or that had been approved within five years of document development. The guideline suggests the use of EBMTs plus lifestyle modification in patients with a BMI of ≥ 30 kg/m2, or with a BMI of 27.0-29.9 kg/m2 with at least 1 obesity-related comorbidity. Furthermore, it suggests the utilization of intragastric balloons and devices for endoscopic gastric remodeling (EGR) in conjunction with lifestyle modification for this patient population.

Asunto(s)

Humanos , Cirugía Bariátrica/normas , Metabolismo , Obesidad/cirugía , Endoscopía Gastrointestinal

RESUMEN

BACKGROUND: The COVID-19 pandemic saw an acceleration in virtual-visits (VV) for healthcare delivery. However, the impact of virtual care in metabolic/bariatric surgery (MBS) programs is not well described. METHODS: Appointment data from three time-points: pre-pandemic (1/1/19-3/15/20, n = 19,290), pandemic (3/16/20-10/31/21, n = 29,459) and current-state (11/1/21-12/31/2022, n = 24,270) was retrieved in our multi-hospital ambulatory MBS program. Appointments were grouped by health care provider (HCP) (MD, dietician, and psychologist) and type (VV and in-person). Surveys assessing patient satisfaction were distributed electronically. All pre-op and post-op appointment data was analyzed for the time-points above. Appointment completion rates and patient reported preferences were described. RESULTS: Our data showed an increase in scheduled VV from 0.5% for all HCP visits to 81% during the pandemic and a current VV visit of 77%. The number of completed VV increased for all HCPs, most prominently for dieticians. Parallel to this, the percentage of no-show visits also improved for all HCP, with MDs having the lowest no-show rate currently. Survey data revealed 89% of patients experience added benefits with VV and > 90% reported their VV experience as very good. VV were preferred over in-person visits for psychologists and dietitians (> 61%), but the majority preferred to see MDs in-person (70%). CONCLUSIONS: Our findings reveal significant changes in healthcare utilization trends since the transition to virtual care. While overall satisfaction with virtual care is high, most patients prefer in-person visits with MDs. Thus, multi-disciplinary MBS care can be performed effectively using a hybrid model to ensure efficient distribution of resources.

Asunto(s)

Cirugía Bariátrica , COVID-19 , Aceptación de la Atención de Salud , Satisfacción del Paciente , SARS-CoV-2 , Telemedicina , Humanos , COVID-19/epidemiología , Femenino , Masculino , Adulto , Aceptación de la Atención de Salud/estadística & datos numéricos , Persona de Mediana Edad , Obesidad Mórbida/cirugía , Obesidad Mórbida/terapia , Pandemias , Citas y Horarios

RESUMEN

This joint ASGE-ESGE guideline provides an evidence-based summary and recommendations regarding the role of endoscopic bariatric and metabolic therapies (EBMTs) in the management of obesity. The document was developed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework. It evaluates the efficacy and safety of EBMT devices and procedures that currently have CE mark or FDA-clearance/approval, or that had been approved within five years of document development. The guideline suggests the use of EBMTs plus lifestyle modification in patients with a BMI of ≥ 30 kg/m2, or with a BMI of 27.0-29.9 kg/m2 with at least 1 obesity-related comorbidity. Furthermore, it suggests the utilization of intragastric balloons and devices for endoscopic gastric remodeling (EGR) in conjunction with lifestyle modification for this patient population.

Asunto(s)

Cirugía Bariátrica , Endoscopía Gastrointestinal , Balón Gástrico , Obesidad , Humanos , Endoscopía Gastrointestinal/métodos , Obesidad/complicaciones , Adulto , Índice de Masa Corporal

RESUMEN

This joint ASGE-ESGE guideline provides an evidence-based summary and recommendations regarding the role of endoscopic bariatric and metabolic therapies (EBMTs) in the management of obesity. The document was developed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework. It evaluates the efficacy and safety of EBMT devices and procedures that currently have CE mark or FDA-clearance/approval, or that had been approved within five years of document development. The guideline suggests the use of EBMTs plus lifestyle modification in patients with a BMI of ≥30 kg/m2, or with a BMI of 27.0-29.9 kg/m2 with at least 1 obesity-related comorbidity. Furthermore, it suggests the utilization of intragastric balloons and devices for endoscopic gastric remodeling (EGR) in conjunction with lifestyle modification for this patient population.

Asunto(s)

Cirugía Bariátrica , Endoscopía Gastrointestinal , Obesidad , Humanos , Cirugía Bariátrica/efectos adversos , Endoscopía Gastrointestinal/normas , Endoscopía Gastrointestinal/métodos , Obesidad/complicaciones , Adulto , Balón Gástrico/efectos adversos

RESUMEN

There are few peer-reviewed studies documenting saturated buffer annual nitrate (NO3 ) removal or that have assessed the federal practice standard design criteria. Drainage flow, NO3 , and dissolved reactive phosphorus (DRP) were monitored at three saturated buffers in Illinois, USA, for a combined 10 site-years. Nitrate loss reduction averaged 48 ± 19% with removals of 3.5-25.2 kg NO3 -N ha-1 annually. Median DRP concentrations at all sampling locations were at the analytical detection limit of 0.01 mg L-1 . The current design paradigm (i.e., USDA practice standard) prescribes there should be no flow bypassing the saturated buffer at flow rates that are ≤5% of the peak drainage system flow rate. The drainage coefficient-based and Manning's equation-based peak flow estimates were higher and lower, respectively, than the observed annual peaks in all years. This illustrated inherent uncertainty introduced early in the design process, which can be further compounded by dynamic in-buffer hydrology. The percentage of the observed peak flow rate at which bypass initiated ranged across an order of magnitude between sites (4.4-8.1% of peak flow rate at one site and 42-49% of peak at another) despite the buffers providing relatively similar NO3 removal. Bypass at one site (SB2) was related to the concept of "antecedent buffer capacity filled," which was defined as the 5-d average water depth in the middle control structure chamber expressed as a relative percentage of the bypass stop log height. This design flow analysis serves as a call to further evaluate predictive relationships and design models for edge-of-field practices.

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Core Ideas Three saturated buffers in Illinois provided an ≈50% annual reduction in NO3 load. Observed peak flow rates differed from estimation methods used for design purposes. Two sites had relatively similar nitrate removals but different bypass trends. "Antecedent buffer capacity filled" was the water depth in the middle chamber as a percent of stop log height.

Asunto(s)

Monitoreo del Ambiente , Nitratos , Agricultura , Hidrología , Illinois , Nitratos/análisis , Nitrógeno/análisis , Fósforo/análisis

RESUMEN

Permeable pavements are a common solution for stormwater management. Porous areas in the pavements allow water to percolate into the subsurface layers, reducing surface runoff. However, it is common for substances to clog the voids, decreasing the porous area and permeability of the pavement system. This study examined the change in permeability over time at a site with two permeable pavement systems, the JW Eco-technology (JW) and pervious concrete (PC). Square frames SF-4 and SF-9 were used to perform falling-head and constant-head permeability tests, respectively. Results show that JW had a similar permeability across the test locations, 6.27-7.64 cm/s when using SF-4, and 0.95-1.00 cm/s when using SF-9. While the permeability at the center locations of PC showed no significant loss of permeability, there was a significant reduction of permeability on the corner and edge areas, where permeability ranged 0.28-1.73 cm/s using SF-4 and 0.14-0.36 cm/s using SF-9, suggesting the occurrence of clogging over time at corner locations. Furthermore, the measured values highlighted the measurement variability in permeability between the falling-head based method and the constant-head method, with measurements from SF-4 being approximately 6.2-7.6 and 2.0-5.7 times higher than those from SF-9 on JW and PC, respectively. In addition, as no current literature quantifies the relationship between permeability and extent of clogging for the JW Eco-technology pavement, evaluation of the proportionate change in permeability with respect to voids, or individual aqueducts, of JW pavement were investigated. While not a 1:1 linear relationship, data indicate that the permeability increased with an increase in non-blocked aqueducts. The JW pavement maintained more than 50% of its capacity when half of the aqueducts were fully blocked. Even when only one aqueduct was clear from clogging, the system had 36% (SF-4) and 19% (SF-9) of maximum permeable capacity.

RESUMEN

OBJECTIVE: The effects of sleeve gastrectomy (SG) on functional connectivity (FC) and associations with weight loss and eating-related cognitive control were investigated. METHODS: In a longitudinal study, 14 SG patients (13 female; 42.1 presurgery BMI) completed study visits 1 month pre surgery and 12 months post surgery. Patients completed the Dutch Eating Behavior Questionnaire and resting-state functional magnetic resonance imaging scanning to measure FC. Data were analyzed using a seed-to-voxel approach in the CONN Toolbox to investigate pre-/postsurgery changes (n = 12) and to conduct predictive analysis (n = 14). RESULTS: Seed-to-voxel analysis revealed changes in magnitude (decreases) and directionality (positively correlated to anticorrelated) of FC pre to post surgery within and between default mode network, salience network, and frontoparietal network nodes [Family-Wise Error (FWE) corrected at P < 0.05]. Baseline FC of the nucleus accumbens (with insula) and hypothalamus (with precentral gyrus) predicted 12-month post-SG % total weight loss (FWE-P < 0.05). Baseline FC of the hippocampus, frontoparietal network, and default mode network nodes predicted improvement in cognitive control of eating behavior 12 months after SG (FWE-P < 0.05). CONCLUSIONS: Our findings demonstrate changes in FC magnitude and directionality post versus pre surgery within and between resting-state networks and frontal, paralimbic, and visual areas in SG patients. Baseline FC predicted weight loss and changes in cognitive control of food intake behavior at 12 months. These could serve as predictive biomarkers for bariatric surgery.

Asunto(s)

Encéfalo/fisiología , Trastornos de Alimentación y de la Ingestión de Alimentos/cirugía , Gastrectomía , Vías Nerviosas/fisiología , Obesidad Mórbida/cirugía , Descanso/psicología , Pérdida de Peso/fisiología , Adulto , Cirugía Bariátrica/métodos , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Cognición/fisiología , Conducta Alimentaria/fisiología , Trastornos de Alimentación y de la Ingestión de Alimentos/complicaciones , Trastornos de Alimentación y de la Ingestión de Alimentos/diagnóstico , Trastornos de Alimentación y de la Ingestión de Alimentos/fisiopatología , Femenino , Lóbulo Frontal/fisiopatología , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Vías Nerviosas/diagnóstico por imagen , Obesidad Mórbida/diagnóstico , Obesidad Mórbida/fisiopatología , Obesidad Mórbida/psicología , Pronóstico , Descanso/fisiología , Resultado del Tratamiento

RESUMEN

The combined use of biochar and compost as a soil amendment presents benefits to crops and nutrient cycling. Although there are literature reviews regarding biochar and biochar-compost mixtures, a quantitative literature review on the role of co-composted biochar (hereby called COMBI) in plant productivity is currently missing. The goal of this review paper is to find evidence-based measures of the effects of application rates, soil pH, plant types, biochar feedstock, and compost materials, on plant productivity. Plant productivity covers a variety of measurements but mostly refers to grain yield and above-ground biomass. Response ratio was selected as the effect size. Funnel plot showed that the studies were reasonably symmetrically distributed around the mean effect size. Results showed that application rates of <20 t/ha and >30 t/ha significantly increased plant productivity by 48.3 and 15.7%, respectively, while no significant yield increases were found for the application rates between 20 and 30 t/ha. When data was grouped based on the soil pH, the greatest increase in plant productivity was found to be at acidic soil pH values (pH 4-5), which was expected because the liming effect of biochar is often reported as one of the main mechanisms behind the increased crop yields. When different plant species were compared, cereal grasses grown with COMBI yielded significantly higher grain yields (39.7%). Rice husk biochar yielded the highest increase in productivity but this result was based on only one study. The second highest increase was obtained with wood-based biochars (29.4%) based on ten studies. The effect sizes found with our meta-analyses are based on 14 research works worldwide and represent the most updated information regarding the effects of COMBI on plant production. As more data on COMBI become available, data analyses can be updated to make more robust comparisons.

Asunto(s)

Carbón Orgánico , Compostaje/métodos , Desarrollo de la Planta , Agricultura , Biomasa , Productos Agrícolas , Fertilizantes , Oryza , Suelo , Madera , Zea mays

RESUMEN

Prepackaged leafy green vegetables represent one of the fastest growing segments of the fresh-produce industry in the United States. Several steps in the production process have been mechanized to meet the downstream demand for prebagged lettuces. The growth in this market, however, has come with drawbacks, and chief among them are consumers finding wild animals in prepackaged crops. These incidents may signal an overburdened produce supply chain, but we currently lack the information needed to determine if this is a food-safety problem or food-quality concern. Here, we address this gap by reviewing online media coverage of wild vertebrates found in prepackaged produce items by customers in the United States. We discovered 40 independent incidents since 2003 with 95% having occurred during 2008-2018, suggesting that the frequency of incidents may have increased during the last decade. The minority of incidents included wild animals found in organic produce (27.5%), whereas the majority involved conventionally grown crops (72.5%). Most incidents involved amphibians (52.5%) and reptiles (22.5%), while fewer contained mammals (17.5%) and birds (7.5%). Frogs and toads made up all of the amphibian-related incidents, with more than 60% comprising small-bodied treefrogs found in various types of fresh leafy greens. At least seven incidents involved Pacific Treefrogs (Hyliola regilla) and three comprised Green Anoles (Anolis carolinensis). One lizard and nine frogs were found alive, and at least two frogs were released into non-native areas. This is the first review quantifying incidents of vertebrates found by customers in prepackaged produce, yet it remains unclear whether these occurrences indicate a food-safety crisis or a complaint against food quality. Nevertheless, wild animals can spread diseases to humans via contaminated produce, therefore we contend that industry professionals can reduce the potential health risk to their consumers and negative economic consequences to themselves through increased attention to this matter.

Asunto(s)

Medios de Comunicación/estadística & datos numéricos , Contaminación de Alimentos/estadística & datos numéricos , Embalaje de Alimentos/estadística & datos numéricos , Inocuidad de los Alimentos , Internet , Vertebrados , Animales , Anuros , Aves , Mamíferos , Reptiles , Estados Unidos , Verduras

RESUMEN

Runoff from animal production facilities contains various microbial pathogens which pose a health hazard to both humans and animals. Rotavirus is a frequently detected pathogen in agricultural runoff and the leading cause of death among children around the world. Diarrheal infection caused by rotavirus causes more than two million hospitalizations and death of more than 500,000 children every year. Very little information is available on the environmental factors governing rotavirus transport in surface runoff. The objective of this study is to model rotavirus transport in overland flow and to compare the model results with experimental observations. A physically based model, which incorporates the transport of infective rotavirus particles in both liquid (suspension or free-floating) and solid phase (adsorbed to soil particles), has been used in this study. Comparison of the model results with experimental results showed that the model could reproduce the recovery kinetics satisfactorily but under-predicted the virus recovery in a few cases when multiple peaks were observed during experiments. Similarly, the calibrated model had a good agreement between observed and modeled total virus recovery. The model may prove to be a promising tool for developing effective management practices for controlling microbial pathogens in surface runoff.

Asunto(s)

Monitoreo del Ambiente/métodos , Rotavirus/aislamiento & purificación , Microbiología del Suelo , Suelo/química , Movimientos del Agua , Crianza de Animales Domésticos , Cinética , Modelos Teóricos

RESUMEN

The widespread availability of relatively cheap, reliable and easy to use digital camera traps has led to their extensive use for wildlife research, monitoring and public outreach. Users of these units are, however, often frustrated by the limited options for controlling camera functions, the generation of large numbers of images, and the lack of flexibility to suit different research environments and questions. We describe the development of a user-customisable open source camera trap platform named 'WiseEye', designed to provide flexible camera trap technology for wildlife researchers. The novel platform is based on a Raspberry Pi single-board computer and compatible peripherals that allow the user to control its functions and performance. We introduce the concept of confirmatory sensing, in which the Passive Infrared triggering is confirmed through other modalities (i.e. radar, pixel change) to reduce the occurrence of false positives images. This concept, together with user-definable metadata, aided identification of spurious images and greatly reduced post-collection processing time. When tested against a commercial camera trap, WiseEye was found to reduce the incidence of false positive images and false negatives across a range of test conditions. WiseEye represents a step-change in camera trap functionality, greatly increasing the value of this technology for wildlife research and conservation management.

Asunto(s)

Periféricos de Computador , Procesamiento de Imagen Asistido por Computador/métodos , Tecnología de Sensores Remotos/métodos , Vida Silvestre , Animales , Animales Salvajes/fisiología , Procesamiento de Imagen Asistido por Computador/instrumentación , Tecnología de Sensores Remotos/instrumentación , Sensibilidad y Especificidad

RESUMEN

OBJECTIVE: Missed appointments decrease clinic capacity and negatively affect health outcomes. The objective of this study was to increase the proportion of filled initial psychiatry appointments in an urban, hospital-based primary care practice. METHODS: Patients were identified as having a high or low risk of missing their initial psychiatry appointments based on prior missed medical appointments. High-risk patients were referred to a walk-in clinic instead of a scheduled appointment. The primary outcome was ratio of filled appointments to booked appointments. We used a statistical process control chart (p chart) to measure improvement. Secondary outcomes were percentages of patients from historically underserved groups who received an initial psychiatry evaluation before and after the intervention. RESULTS: The average ratio of filled to booked initial appointments increased from 59% to 77% after the intervention, and the p chart confirmed that this change represented special cause variation. No statistically significant demographic differences between the patients who received psychiatric evaluations before and after the intervention were found. CONCLUSIONS: Missed initial psychiatry appointments can be accurately predicted by prior missed medical appointments. A referral-based walk-in clinic is feasible and does not reduce access to care for historically underserved patient groups.

Asunto(s)

Accesibilidad a los Servicios de Salud/tendencias , Servicio Ambulatorio en Hospital/tendencias , Cooperación del Paciente/psicología , Atención Primaria de Salud/tendencias , Psiquiatría/tendencias , Derivación y Consulta/tendencias , Adulto , Citas y Horarios , Femenino , Humanos , Masculino , Atención Primaria de Salud/métodos , Psiquiatría/métodos

RESUMEN

Washoff of 17 pyrethroid products resulting from a 1-h, 25.4-mm rainfall occurring 24 h after application was measured in indoor studies with concrete slabs. These products included different pyrethroid active ingredients and a range of formulation types. Based on this replicated study, 5 product pairs with contrasting washoff behaviors were chosen for an outdoor study using 6 full-scale house fronts in central California. Products in 4 of these pairs were applied once to different rectangular areas on the driveway (1 product in each pair to 3 house lots and the other to the remaining 3 house lots). The products in the fifth pair were applied 3 times at 2-mo intervals to vertical stucco walls above the driveway. All house lots received natural and simulated rainfall over 7 mo. Indoor studies showed differences up to 170-fold between paired products, whereas the maximum difference between paired products in the field was only 5-fold. In the pair applied to the wall, 1 product had 91 times the washoff of the other in the indoor study, whereas in the field the same product had 15% lower washoff. These results show that, although the formulation may influence washoff under actual use conditions, its influence is complex and not always as predicted by indoor experiments. Because the formulation also affects insect control, washoff research needs to be conducted together with efficacy testing.

Asunto(s)

Insecticidas/análisis , Piretrinas/análisis , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua , California , Química Farmacéutica , Vivienda , Control de Insectos , Lluvia

RESUMEN

The availability of affordable 'recreational' camera traps has dramatically increased over the last decade. We present survey results which show that many conservation practitioners use cheaper 'recreational' units for research rather than more expensive 'professional' equipment. We present our perspective of using two popular models of 'recreational' camera trap for ecological field-based studies. The models used (for >2 years) presented us with a range of practical problems at all stages of their use including deployment, operation, and data management, which collectively crippled data collection and limited opportunities for quantification of key issues arising. Our experiences demonstrate that prospective users need to have a sufficient understanding of the limitations camera trap technology poses, dimensions we communicate here. While the merits of different camera traps will be study specific, the performance of more expensive 'professional' models may prove more cost-effective in the long-term when using camera traps for research.

Asunto(s)

Animales Salvajes , Conservación de los Recursos Naturales/métodos , Recolección de Datos/métodos , Fotograbar/métodos , Animales , Invenciones , Recreación

RESUMEN

The major pathways for transport of pyrethroids were determined in runoff studies conducted at a full-scale test facility in central California, USA. The 6 replicate house lots were typical of front lawns and house fronts of California residential developments and consisted of stucco walls, garage doors, driveways, and residential lawn irrigation sprinkler systems. Each of the 6 lots also included a rainfall simulator to generate artificial rainfall events. Different pyrethroids were applied to 5 surfaces­driveway, garage door and adjacent walls, lawn, lawn perimeter (grass near the house walls), and house walls above grass. The volume of runoff water from each house lot was measured, sampled, and analyzed to determine the amount of pyrethroid mass lost from each surface. Applications to 3 of the house lots were made using the application practices typically used prior to recent label changes, and applications were made to the other 3 house lots according to the revised application procedures. Results from the house lots using the historic application procedures showed that losses of the compounds applied to the driveway and garage door (including the adjacent walls) were 99.75% of total measured runoff losses. The greatest losses were associated with significant rainfall events rather than lawn irrigation events. However, runoff losses were 40 times less using the revised application procedures recently specified on pyrethroid labels.

Asunto(s)

Insecticidas/análisis , Piretrinas/análisis , Movimientos del Agua , Contaminantes Químicos del Agua/análisis , California , Materiales de Construcción , Vivienda , Poaceae , Lluvia , Suelo , Contaminación del Agua/prevención & control

RESUMEN

We present a novel approach to analyse the fracture of fibre-reinforced composites. Experimental results on mode I fracture of glass fibre and carbon fibre unidirectional laminates presented here and published by others in the open literature formed the basis for the analytical and numerical results presented. When details of the external loading rate are explicitly accounted for, a new picture of fracture emerges, which encompasses the possibility for non-smooth crack growth and the necessity to relax the use of a critical strain energy release rate as a criterion for crack advancement. Results predicted by adopting the analytical model presented here are seen to capture a wide variety of fracture responses that have been observed previously.

RESUMEN

A system capable of reliably detecting lapses in responsiveness ('lapses') has the potential to increase safety in many occupations. We have developed an approach for detecting the state of lapsing with second-scale temporal resolution using data from 15 subjects performing a one-dimensional (1D) visuomotor tracking task for two 1 h sessions while their electroencephalogram (EEG), facial video, and tracking performances were recorded. Lapses identified using a combination of facial video and tracking behaviour were used to train the classification models. Linear discriminant analysis was used to form detection models based on individual subject data and stacked generalization was utilized to combine the outputs of multiple classifiers to obtain the final prediction. The performance of detectors estimating the lapse/not-lapse state at 1 Hz based on power spectral features, approximate entropy, fractal dimension, and Lempel-Ziv complexity of the EEG was compared. Best lapse state estimation performance was achieved using the detector model created using power spectral features with an area under the curve from receiver operating characteristic analysis of 0.86 ± 0.03 (mean±SE) and an area under the precision-recall curve of 0.43 ± 0.09. A novel technique was developed to provide improved estimation of accuracy of detection of variable-duration events. Via this approach, we were able to show that the detection of lapse events from spectral power features was of moderate accuracy (sensitivity = 73.5%, selectivity = 25.5%).

Asunto(s)

Electroencefalografía/métodos , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Adolescente , Adulto , Humanos , Masculino , Estimulación Luminosa/métodos , Adulto Joven

RESUMEN

A device capable of continuously monitoring an individual's levels of alertness in real-time is highly desirable for preventing drowsiness and microsleep related accidents. This paper presents a development of non-intrusive and light-insensitive video-based system that uses computer-vision methods to measure facial metric for identifying visible facial signs of drowsiness and behavioral microsleep. The developed system uses a remotely placed camera with a near-infrared illumination to acquire the video. The computer-vision methods are then applied to sequentially localize face, eyes, and eyelids positions to measure ratio of eye closure. The system was evaluated in frontal images of nine subjects with varying facial structures and exhibiting several ratio of eye closure and eye gaze under fully dark and ambient lighting conditions. The preliminary results showed promising results with sufficient accuracy to distinguish between fully closed, half closed, and fully open eyes.

Asunto(s)

Párpados/fisiología , Monitoreo Fisiológico/instrumentación , Grabación en Video/métodos , Cara/fisiología , Femenino , Humanos , Masculino , Monitoreo Fisiológico/métodos , Fases del Sueño/fisiología , Vigilia/fisiología

RESUMEN

Lapses in responsiveness ('lapses'), particularly microsleeps and attention lapses, are complete disruptions in performance from approximately 0.5-15 s. They are of particular importance in the transport sector in which there is a need to maintain sustained attention for extended periods and in which lapses can lead to multiple-fatality accidents.

Asunto(s)

Atención/fisiología , Encéfalo/fisiología , Electroencefalografía/métodos , Desempeño Psicomotor/fisiología , Fases del Sueño/fisiología , Humanos