Chronic Lung Function Decline in Cotton Textile Workers: Roles of Historical and Recent Exposures to Endotoxin

BackgroundLong-term occupational exposure to cotton dust that contains endotoxin is associated with chronic respiratory symptoms and excessive decline in forced expiratory volume in 1 sec (FEV1), but the mechanisms of endotoxin-related chronic airflow obstruction remain unclear.ObjectiveIn the current study, we examined temporal aspects of the exposure-response relationship between airborne endotoxin exposure, longitudinal change in FEV1, and respiratory symptoms in a cohort of Chinese cotton textile workers.MethodsThis prospective cohort study followed 447 cotton textile workers from 1981 to 2006. at approximately 5-year intervals. We used a generalized estimating equations approach to model FEV1 level and respiratory symptoms as a function of past exposure (cumulative exposure up to the start of the most recent 5-year survey interval) and cumulative exposure (within the most recent interval) to endotoxins, after adjusting for other covariates. Models were stratified by active versus retired work status and by years employed before the baseline survey (< 5 and > or = 5 years).Results and conclusionsPast exposure to endotoxin was associated with reduced FEV1 level among retired cotton workers. Among all cotton workers, past exposure was more strongly associated with reduced FEV1 for those hired < 5 years before baseline than for those who were hired > or = 5 years after baseline. Recent endotoxin exposure was significantly associated with byssinosis, chronic bronchitis, and chronic cough

Asthma in changing environments - chances and challenges of international research collaborations between South America and Europe - study protocol and description of the data acquisition of a case-control-study

<p>Abstract</p> <p>Background</p> <p>Asthma in children is an emerging public health problem in South America. So far, research in this part of the world is limited. This paper presents the methodology and description of the data acquisition of an asthma case-control study conducted in the Central South of Chile.</p> <p>Methods/Design</p> <p>A hospital-based case-control study about asthma (188 cases, 294 controls) in children (6-15 years) was carried out in Valdivia, Chile between November 2008 and December 2009. Data on asthma risk factors were collected by computer-assisted personal interview using validated questions from e.g. ISAAC phase II. Data on household dust exposure (endotoxin, allergen analyses), skin prick tests to most common allergens, stool examinations for parasitic infection, and blood samples (total IgE, genetics) were collected. Additionally, 492 randomly chosen blood donors were recruited in order to assess allele frequencies in the population of Valdivia.</p> <p>Discussion</p> <p>Overall 1,173 participants were contacted. Response was 82% among cases and 65% among controls. Atopic sensitization was high (78% among cases, 47% among controls). Cases had a statistically significantly (p < .0001) increased self-reported 12-month prevalence of symptoms of rhinitis (82% vs. 51%) and wheeze (68% vs. 16%). The study is well placed to address current hypotheses about asthma and its correlates in the South American context. Results of this study might help develop novel, innovative and individualized prevention strategies in countries in transition with respect to the South American context.</p

Tile based HEVC video for head mounted displays

360 degrees video services with resolutions of UHD and beyond for Virtual Reality head mounted displays are a challenging task due to limits of video decoders in constrained end devices. Adaptivity to the current user viewport is a promising approach but incurs significant encoding overhead when encoding per user or set of viewports. A more efficient way to achieve viewport adaptive streaming is to facilitate motion-constrained HEVC tiles. Original content resolution within the user viewport is preserved while content currently not presented to the user is delivered in lower resolution. A lightweight aggregation of varying resolution tiles into a single HEVC bitstream can be carried out on-the-fly and allows usage of a single decoder instance on the end device

Interception and Retention of Chernobyl-derived 134-Cs, 137Cs and 106Ru in a Spruce Stand.

The time dependence of the specific activity of Chernobyl-derived 134Cs, 137Cs and 106Ru was determined in vegetation and soil samples from an old spruce stand within a period of 600 days after the beginning of the radioactive fallout. The results show that 70% of the total activity of radiocesium and 60% of radioruthenium deposited in the spruce stand were retained intinially in the canopy. They were removed from the needles and twigs as a result of weathering (rain, wind, litter fall) and transferred to the forest floor, but only rather slowly (half-lives in the canopy: radiocesium, 90 days for the period 0&ndash;130 days, 230 days for the period 130&ndash;600 days; radioruthenium, 95 days for the period 0&ndash;200 days). The transfer of radiocesium and ruthenium to the forest floor by litter-fall was small when compared with that of weathering by rain or wind (radiocesium 7%, radioruthenium 8%, with respect to the total activity deposited in the canopy). The total deposition of radiocesium and ruthenium in the spruce stand was higher by 20 and 24%, respectively, than that observed in nearby grassland. The deposition velocity of radiocesium in the spruce stand was estimated at 5.5 mm s&minus;1, higher by a factor of 10 than the figure for grassland. Similar values were found for radiorutheniu

Peak bitrate reduction for multi-party video conferencing using SHVC

Real-time video applications, such as multi party video conferencing, involve the simultaneous transport of multiple and potentially multi-layered video sources to participating or interested parties. It is desirable to mix these multiple source videos into a single video stream at intermediary nodes in the network, e.g. at Multipoint Control Units (MCU). This has the advantage of reduced application and transport complexity on the client device while allowing single hardware decoder devices to consume the content. This paper proposes a solution, which uses the scalable extension of H.265/HEVC (SHVC), and that generates a single bitstream out of several sources by a low-complexity operation. In addition, the presented technique drastically reduces the peak bitrate at layout change events in comparison to state-of-the-art solutions

Effects of Acid Irrigation and Liming on the Migration of Radiocesium in a Forest Soil as Observed by Field Measurements.

The effect of normal irrigation, acid irrigation, and liming on the vertical migration of radiocesium from Chernobyl and global fallout was investigated by determining the activity of 134Cs and 137Cs in the upper horizons (LOfl, Of2, Oh, Aeh, Alh, Al) of six experimental plots of a forest soil (spruce stand) as a function of time. For the Of2 and Oh horizons (but not for the LOfl horizon) of the control plots during our period of observation (600 days from 30 April 1986), we found a significant increase in the mean residence half-time (&tau;) of Chernobyl-derived cesium from ~ 70 to 500 days, indicating that Cs is sorbed more strongly with time. The different types of soil management showed an effect only in the Of2 horizon. Irrigation, especially when acid, prevents the increase of &tau; with time. Liming reduces the rate of migration of Cs significantly, even if the plots are irrigated with normal or acid water. Cesium-137 from global fallout was present mainly in the Oh and Aeh horizons, but was less mobile than Chernobyl-derived Cs by one order of magnitude

Respiratory allergies among veterinarians: two cross-sectional surveys from 2006 to 2012

PURPOSE: Animal-related allergy is known to be an occupational hazard among veterinarians; however, there is a lack of data showing to which extent these are affected. We aimed at describing the prevalence of respiratory allergies in this population. METHODS: In two repeated cross-sectional surveys in 2006 and 2012 in Bavaria, we examined the prevalence of wheezing, asthma and allergic rhinitis by questionnaires. We additionally performed multiple regression analysis to identify associated factors. RESULTS: Overall participation rate was above 60%, leading to sample sizes of 512 in 2006 and 596 in 2012, respectively. Prevalences of allergic symptoms ranged from 5.1 to 5.6% for asthma, 17.0 to 20.2% for rhinitis, and 11.4 to 14.3% for wheezing, as well as 7.2 to 11.3% for wheezing without having a cold. The percentage of women in this occupation grew between the first and second survey. There were gender differences in both surveys concerning age and practice type (p < 0.0001). Women had a lower mean age (42.1 vs. 53.0 years in 2012) and worked much more often exclusively with small animals (50.2 vs. 15.9% in 2012). There was a borderline significantly higher prevalence for allergic rhinitis in women than in men in 2012 (20.1 vs. 13.7, p = 0.052). Having allergic rhinitis was clearly associated with wheezing, wheezing without cold and asthma. CONCLUSIONS: In a repeated cross-sectional survey at an interval of 6 years among veterinarians, we found a relatively stable overall prevalence of wheeze, wheeze without having a cold, asthma and allergic rhinitis