229 research outputs found

    Exposure of Highway Maintenance Workers to Fine Particulate Matter and Noise

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    In this study, we assessed the mixed exposure of highway maintenance workers to airborne particles, noise, and gaseous co-pollutants. The aim was to provide a better understanding of the workers' exposure to facilitate the evaluation of short-term effects on cardiovascular health endpoints. To quantify the workers' exposure, we monitored 18 subjects during 50 non-consecutive work shifts. Exposure assessment was based on personal and work site measurements and included fine particulate matter (PM2.5), particle number concentration (PNC), noise (Leq), and the gaseous co-pollutants: carbon monoxide, nitrogen dioxide, and ozone. Mean work shift PM2.5 concentrations (gravimetric measurements) ranged from 20.3 to 321 μg m−3 (mean 62 μg m−3) and PNC were between 1.6×104 and 4.1×105 particles cm−3 (8.9×104 particles cm−3). Noise levels were generally high with Leq over work shifts from 73.3 to 96.0 dB(A); the averaged Leq over all work shifts was 87.2 dB(A). The highest exposure to fine and ultrafine particles was measured during grass mowing and lumbering when motorized brush cutters and chain saws were used. Highest noise levels, caused by pneumatic hammers, were measured during paving and guardrail repair. We found moderate Spearman correlations between PNC and PM2.5 (r = 0.56); PNC, PM2.5, and CO (r = 0.60 and r = 0.50) as well as PNC and noise (r = 0.50). Variability and correlation of parameters were influenced by work activities that included equipment causing combined air pollutant and noise emissions (e.g. brush cutters and chain saws). We conclude that highway maintenance workers are frequently exposed to elevated airborne particle and noise levels compared with the average population. This elevated exposure is a consequence of the permanent proximity to highway traffic with additional peak exposures caused by emissions of the work-related equipmen

    Associations of short-term particle and noise exposures with markers of cardiovascular and respiratory health among highway maintenance workers

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    BACKGROUND: Highway maintenance workers are constantly and simultaneously exposed to traffic-related particle and noise emissions, and both have been linked to increased cardiovascular morbidity and mortality in population-based epidemiology studies. OBJECTIVES: We aimed to investigate short-term health effects related to particle and noise exposure. METHODS: We monitored 18 maintenance workers, during as many as five 24-hour periods from a total of 50 observation days. We measured their exposure to fine particulate matter (PM2.5), ultrafine particles, noise, and the cardiopulmonary health endpoints: blood pressure, pro-inflammatory and pro-thrombotic markers in the blood, lung function and fractional exhaled nitric oxide (FeNO) measured approximately 15 hours post-work. Heart rate variability was assessed during a sleep period approximately 10 hours post-work. RESULTS: PM2.5 exposure was significantly associated with C-reactive protein and serum amyloid A, and negatively associated with tumor necrosis factor α. None of the particle metrics were significantly associated with von Willebrand factor or tissue factor expression. PM2.5 and work noise were associated with markers of increased heart rate variability, and with increased HF and LF power. Systolic and diastolic blood pressure on the following morning were significantly associated with noise exposure after work, and non-significantly associated with PM2.5. We observed no significant associations between any of the exposures and lung function or FeNO. CONCLUSIONS: Our findings suggest that exposure to particles and noise during highway maintenance work might pose a cardiovascular health risk. Actions to reduce these exposures could lead to better health for this population of workers

    Early Placement of Optional Vena Cava Filter in High-Risk Patients with Traumatic Brain Injury

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    Objectives:: Patients sustaining severe trauma are at high risk for the development of venous thromboembolic events (VTE). Pharmacologic VTE prophylaxis may be contraindicated early after trauma due to potential bleeding complications. The purpose of this study was to evaluate safety and feasibility of early prophylactic vena cava filter (VCF) placement and subsequent retrieval in multiple injured patients with traumatic brain injury (TBI). Methods:: Analysis of single-institution case series of consecutive patients who received a prophylactic VCF after severe TBI (Abbreviated Injury Scale, AiS ≥ 3) between August 2003 and October 2006. Results:: A total of 34 optional VCF were prophylactically placed with a median delay of 1 day after trauma (range, 0-7 days). All patients had sustained multiple injuries (median Injury Severity Score 41, range, 18-59) with severe TBI (median AiS 4, range 3-5). Median age was 41 years (range, 17-67 years). Two patients had succumbed before potential filter retrieval. Of the remaining patients, 27 (84%) had their filters uneventfully retrieved between 11 and 32 days (median, 18 days) after placement with no retrieval-related morbidity. Five VCF (16%) were left permanently. In one patient (3%) early inferior vena cava occlusion and deep venous thrombosis occurred 14 days after VCF placement. Symptomatic pulmonary embolism was observed in one patient (3%) 5 days after VCF retrieval. Overall trauma-related mortality was 9%. Conclusions:: Early VCF placement may be of benefit for multiple injured patients with TBI when pharmacologic VTE prophylaxis is contraindicated. VCF retrieval is safe and feasible. Filter placement- and retrieval-related morbidity is lo

    Early Placement of Optional Vena Cava Filter in High-Risk Patients with Traumatic Brain Injury

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    Objectives:: Patients sustaining severe trauma are at high risk for the development of venous thromboembolic events (VTE). Pharmacologic VTE prophylaxis may be contraindicated early after trauma due to potential bleeding complications. The purpose of this study was to evaluate safety and feasibility of early prophylactic vena cava filter (VCF) placement and subsequent retrieval in multiple injured patients with traumatic brain injury (TBI). Methods:: Analysis of single-institution case series of consecutive patients who received a prophylactic VCF after severe TBI (Abbreviated Injury Scale, AiS ≥ 3) between August 2003 and October 2006. Results:: A total of 34 optional VCF were prophylactically placed with a median delay of 1 day after trauma (range, 0-7 days). All patients had sustained multiple injuries (median Injury Severity Score 41, range, 18-59) with severe TBI (median AiS 4, range 3-5). Median age was 41 years (range, 17-67 years). Two patients had succumbed before potential filter retrieval. Of the remaining patients, 27 (84%) had their filters uneventfully retrieved between 11 and 32 days (median, 18 days) after placement with no retrieval-related morbidity. Five VCF (16%) were left permanently. In one patient (3%) early inferior vena cava occlusion and deep venous thrombosis occurred 14 days after VCF placement. Symptomatic pulmonary embolism was observed in one patient (3%) 5 days after VCF retrieval. Overall trauma-related mortality was 9%. Conclusions:: Early VCF placement may be of benefit for multiple injured patients with TBI when pharmacologic VTE prophylaxis is contraindicated. VCF retrieval is safe and feasible. Filter placement- and retrieval-related morbidity is lo

    Tobacco sales prohibition and teen smoking

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    We evaluate one of the most prevalent prohibitory policies: banning the sales of tobacco to teens. We exploit the staggered introduction of sales bans across Switzerland and analyze rich data from 2001 to 2016. The estimates do not indicate an immediate or long-run systematic reduction in the overall prevalence of smoking because of sales bans. We also examine a range of behavioral mechanisms that are key to understand the consequences of prohibitory policies such as habit formation, social appeal of smoking, circumvention behavior, or risk perceptions. Among others, we find that teens circumvent the bans by getting cigarettes from peers. Moreover, teens consider smokers less cool when a sales ban is in place, but they do not consider smoking more dangerous

    Tobacco Sales Prohibition and Teen Smoking

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    We evaluate one of the most prevalent prohibitory policies: banning the sales of tobacco to teens. We exploit the staggered introduction of sales bans across Switzerland and the European Union from 1990 to 2016. The estimates indicate a less than 1 percentage point reduction in teen smoking because of the bans. The reduction is substantially lower than the 5 percentage point reduction expected by health officials. We examine additional outcomes relevant to assessing any prohibitory policy. We find that teens circumvent the bans through peers. Moreover, they consider smokers less cool but do not think smoking is more dangerous

    Particulate matter and subclinical atherosclerosis : associations between different particle sizes and sources with carotid intima-media thickness in the SAPALDIA study

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    Subclinical atherosclerosis has been associated with long-term exposure to particulate matter (PM), but the relevance of particle size and sources of exposure remains unclear.; We investigated the association of long-term exposure to PM10 (≤ 10 μm), PM2.5 (≤ 2.5 μm: total mass, vehicular, and crustal sources), and ultrafine particles [UFP < 0.1 μm: particle number concentration (PNC) and lung-deposited surface area (LDSA)] with carotid intima-media thickness (CIMT).; We used data from 1,503 participants ≥ 50 years old who participated in the third examination of the Swiss SAPALDIA cohort. Exposures were obtained from dispersion models and land-use regression models. Covariate information, including previous cardiovascular risk factors, was obtained from the second and third SAPALDIA examinations.; The adjusted percent difference in CIMT associated with an exposure contrast between the 10th and 90th percentile was 1.58% (95% CI: -0.30, 3.47%) for PM10, 2.10% (95% CI: 0.04, 4.16%) for PM2.5, 1.67% (95% CI: -0.13, 3.48%) for the vehicular source of PM2.5, -0.58% (95% CI: -3.95, 2.79%) for the crustal source of PM2.5, 2.06% (95% CI: 0.03, 4.10%) for PNC, and 2.32% (95% CI: 0.23, 4.40%) for LDSA. Stronger associations were observed among diabetics, subjects with low-educational level, and those at higher cardiovascular risk.; CIMT was associated with exposure to PM10, PM2.5, and UFP. The PM2.5 source-specific analysis showed a positive association for the vehicular source but not for the crustal source. Although the effects of PNC and LDSA were similar in magnitude, two-pollutant and residual-based models suggested that LDSA may be a better marker for the health relevance of UFP. Citation: Aguilera I, Dratva J, Caviezel S, Burdet L, de Groot E, Ducret-Stich RE, Eeftens M, Keidel D, Meier R, Perez L, Rothe T, Schaffner E, Schmit-Trucksäss A, Tsai MY, Schindler C, Künzli N, Probst-Hensch N. 2016. Particulate matter and subclinical atherosclerosis: associations between different particle sizes and sources with carotid intima-media thickness in the SAPALDIA study. Environ Health Perspect 124:1700-1706; http://dx.doi.org/10.1289/EHP161

    The Theta Paradox: 4-8 Hz EEG Oscillations Reflect Both Sleep Pressure and Cognitive Control

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    Human electroencephalographic (EEG) oscillations characterize specific behavioral and vigilance states. The frequency of these oscillations is typically sufficient to distinguish a given state; however, theta oscillations (4-8 Hz) have instead been found in near-opposite conditions of drowsiness during sleep deprivation and alert cognitive control. While the latter has been extensively studied and is often referred to as "frontal midline theta," (fmTheta) the former has been investigated far less but is considered a marker for sleep pressure during wake. In this study we investigated to what extent theta oscillations differed during cognitive tasks and sleep deprivation. We measured high-density EEG in 18 young healthy adults (nine female) performing six tasks under three levels of sleep deprivation. We found both cognitive load and sleep deprivation increased theta power in medial prefrontal cortical areas; however, sleep deprivation caused additional increases in theta in many other, predominantly frontal, areas. The sources of sleep deprivation theta (sdTheta) were task dependent, with a visual-spatial task and short-term memory (STM) task showing the most widespread effects. Notably, theta was highest in supplementary motor areas during passive music listening, and highest in the inferior temporal cortex (responsible for object recognition) during a spatial game. Furthermore, while changes in task performance were correlated with increases in theta during sleep deprivation, this relationship was not specific to the EEG of the same task and did not survive correction for multiple comparisons. Altogether, these results suggest that both during sleep deprivation and cognition theta oscillations may preferentially occur in cortical areas not involved in ongoing behavior.SIGNIFICANCE STATEMENT Electroencephalographic (EEG) research in sleep has often remained separate from research in cognition. This has led to two incompatible interpretations of the function of theta brain oscillations (4-8 Hz): that they reflect local sleep events during sleep deprivation, or that they reflect cognitive processing during tasks. With this study, we found no fundamental differences between theta oscillations during cognition and theta during sleep deprivation that would suggest different functions. Instead, our results indicate that in both cases, theta oscillations are generated by cortical areas not required for ongoing behavior. Therefore, at least in humans, theta may reflect either cortical disengagement or inhibition

    Visuomotor adaptation, internal modelling, and compensatory movements in children with developmental coordination disorder

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    Background: Developmental coordination disorder (DCD) is one of the most prevalent developmental disorders in school-aged children. The mechanisms and etiology underlying DCD remain somewhat unclear. Altered visuomotor adaptation and internal model deficits are discussed in the literature. Aims: The study aimed to investigate visuomotor adaptation and internal modelling to determine whether and to what extent visuomotor learning might be impaired in children with DCD compared to typically developing children (TD). Further, possible compensatory movements during visuomotor learning were explored. Methods and procedures: Participants were 12 children with DCD (age 12.4 ± 1.8, four female) and 18 age-matched TD (12.3 ± 1.8, five female). Visuomotor learning was measured with the Motor task manager. Compensatory movements were parameterized by spatial and temporal variables. Outcomes and results: Despite no differences in visuomotor adaptation or internal modelling, significant main effects for group were found in parameters representing movement accuracy, motor speed, and movement variability between DCD and TD. Conclusions and implications: Children with DCD showed comparable performances in visuomotor adaptation and internal modelling to TD. However, movement variability was increased, whereas movement accuracy and motor speed were reduced, suggesting decreased motor acuity in children with DCD
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