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Background: While there is a wide body of literature addressing noise-induced hearing loss (NIHL) and hand-arm vibration syndrome (HAVS) independently, relatively few studies have considered the combined effects of noise and vibration. These studies have suggested an increased risk of NIHL in workers with vibration white finger (VWF), though the relationship remains poorly understood. Aims: To determine whether hearing impairment is worse in noise-exposed workers with VWF than in workers with similar noise exposures but without VWF. Methods: The Quebec National Institute of Public Health audiometric database was used in conjunction with work-related accident and occupational diseases data from the Quebec workers' compensation board to analyse differences in audiometry results between vibration-exposed workers in the mining and forestry industries and the overall source population, and between mining and forestry workers with documented VWF and those without VWF. The International Organization for Standardization (ISO) 7029 standards were used to calculate hearing loss not attributable to age. Results: 15 751 vibration-exposed workers were identified in an overall source population of 59 339. Workers with VWF (n = 96) had significantly worse hearing at every frequency studied (500, 1000, 2000 4000 Hz) compared with other mining and forestry workers without VWF. Conclusions: This study confirms previous findings of greater hearing loss at higher frequencies in workers with VWF, but also found a significant difference in hearing loss at low frequencies. It therefore supports the association between combined noise and hand-arm vibration (HAV) exposure and NIHL. [ABSTRACT FROM AUTHOR]

This study examines the spatial distribution of three species of wolffish in the Gulf of St. Lawrence on the basis of trawl surveys., A standardized method is proposed to assess species-habitat associations for the purpose of management and recovery of endangered marine species., Catch data (presence/absence in trawl sets) and landscape and environmental characteristics of the sea floor were aggregated using a common grid (100 km2 cells), and species-habitat relationships were explored using geospatial tools., Relative occurrence was lower and area of occupancy and concentration were much smaller for the northern wolffish ( Anarhichas denticulatus) than for the spotted wolffish ( Anarhichas minor), with the striped wolffish ( Anarhichas lupus) being most widespread. Significant relationships were observed between values of the local spatial autocorrelation Gi* statistic and habitat descriptors for each of the three species., Hot spots for spotted and striped wolffish occurred in areas where a greater diversity of relief and habitats was found. They were associated with intermediate depths, coarse sediments and rock outcrops, and lower salinities and temperatures than for northern wolffish., Northern wolffish appeared to be associated mainly with the deep water sloped habitat bordering deep channels, whereas spotted and striped wolffish both concentrated most intensively into neighbouring deep water shelf habitats and relatively cold shallow to mid-depth shelf habitats of the northern Gulf., The RDA analysis indicated a significant relationship between Gi* scores of the three species and environmental variables. The model explained 52% of the variability in the data; northern wolffish showed a distinct relationship compared with the two other species., The conservation of marine species and protection of their habitats pose a major challenge given the limited amount of information typically available on rare species and the scale and complexity of marine processes that affect those species. The broad-scale approach presented here allows the provision of advice on important habitats on the basis of the best available knowledge., Copyright © 2013 Her Majesty the Queen in Right of Canada [ABSTRACT FROM AUTHOR]

The extent of spatial (depth and locality) and temporal (season and year) variabilities in condition and relative muscle size (a direct proxy of growth) were examined in male and female adult and non-adult snow crabs Chionoecetes opilio. Condition, determined from the relative size of the digestive gland and moisture content of the muscle and digestive gland, and muscle size, determined as the ratio of merus muscle mass over merus volume, separated as different processes in a principal component analysis. Snow crabs showed a wide range of condition and muscle size values. Overall, the condition was better in non-adult than in adult crabs, with adult females being in worst condition, and muscle size was larger in males than in females. Condition variability was greater for seasonal compared to annual samples, probably reflecting annual molt cycles. In contrast, the muscle size variability was greater for annual compared to seasonal samples, possibly as a result of changing crab abundance and competition intensity during recruitment pulses. Condition and muscle size increased through summer in males and immature females, although to different extents depending on instar, but did not change in adult females. Both condition and muscle size were highly variable at the investigated spatial scales. Condition and muscle size had a significant effect on gonad size, once the effect of crab size was removed, suggesting a direct link between these two parameters and reproductive capability. [ABSTRACT FROM AUTHOR]

Vibrio cholerae causes a dehydrating diarrheal illness that can be rapidly fatal in the absence of specific treatment. The organism is an historic scourge and, like similar infectious diseases, may have influenced the evolution of the human genome. We report here the results of the first candidate gene association study of cholera. In a family-based study of 76 pedigrees from Dhaka, Bangladesh, we evaluated the association between cholera and five candidate genes—the cystic fibrosis transmembrane receptor; lactoferrin; long palate, lung and nasal epithelium clone 1 (LPLUNC1); estrogen-related receptor alpha and calcium-activated chloride channel 1. We found a significant association with a marker in the promoter region of LPLUNC1 (rs11906665), a member of a family of evolutionarily conserved innate immunity proteins. An earlier microarray-based study of duodenal biopsies showed significantly increased expression of LPLUNC1 in cholera patients compared with healthy control subjects. Our results suggest that variation in host innate immune responses may influence the outcome of exposure to V. cholerae in an endemic setting.Genes and Immunity (2009) 10, 267–272; doi:10.1038/gene.2009.2; published online 12 February 2009 [ABSTRACT FROM AUTHOR]

Experimental evidence was produced and gathered to demonstrate the distinct nature of nanostructured polymer microcomposites. The case of a polymer composite consisting of a high-content of micrometric quartz with a small adjunct of nanoclay is discussed. Emphasis is put on dielectric behavior studies while some results on thermal characteristics are presented. Overall results strongly support the potential of this class of insulating material for electrotechnical applications. [ABSTRACT FROM AUTHOR]

Prolonged swimming capacity (critical swimming speed, Ucrit, protocol) and metabolism were measured for 14 Atlantic cod Gadus morhua exposed to seven oxygen levels within the non-lethal range normally encountered in the Gulf of St Lawrence (35 to 100% saturation). Burst-and-coast swimming was triggered earlier (at lower speeds) in hypoxia, and burst-and-coast movements were more frequent in hypoxia than in normoxia at low speeds. Furthermore, the metabolic scope beyond the metabolic rate at which Atlantic cod resorted to burst-and-coast movements decreased gradually as ambient oxygen concentration dropped. Overall, fewer burst-and-coast movements were observed in hypoxia while the distance swum in burst-and-coast mode remained c. 1% of the total distance swam in all tests. Oxygen availability had no effect on the rate of increase in metabolic rate with increasing velocity <50 cm s−1, but limited swimming performances and metabolic rate at higher speeds. The prevailing low oxygen tensions on the bottom in the deep channels may impair the swimming capacity of Atlantic cod in the estuary and northern Gulf of St Lawrence. [ABSTRACT FROM AUTHOR]

Muscle protein decreases only during prolonged starvation of Atlantic cod ( Gadus morhua , Gadidae), but in the absence of protein renewal, muscle metabolic capacities may decrease before marked loss of muscle protein. This study aimed at elucidating the threshold at which decreases in growth and condition reduce muscle metabolic capacities, as well as identifying the indicators that best explain changes in metabolic capacities. To generate a wide spectrum of individual growth rates, condition factors and proximate compositions, cod showing different initial condition were fed or starved for different periods of time. The relationships between muscle proteins and metabolic enzyme activities (LDH and CCO) on one hand, and growth rate, condition factor, hepato- and gonadosomatic index and muscle and liver water and energy contents, on the other hand, were examined through linear regression models. Multiple linear regressions explained a large proportion of the observed variability in proteins and enzyme activities. Changes in LDH and CCO activities were not driven by changes in growth rate. Muscle water was the only significant correlate for both enzymes. Enzyme activities decreased as soon as muscle water began to rise. Increases in water content from 79 to 92% resulted in a 10-fold decrease in LDH and CCO activities. [ABSTRACT FROM AUTHOR]

A microbial community of a compost biofilter treating toluene vapors was investigated using serum-bottle assays and mineral-agar plates. Toluene was not consumed in the absence of oxygen. However, filter-bed extracts exposed to toluene vapor as the only carbon source produced distinct colony types (phenotypic groups) that were counted separately. Strains from each group were isolated and checked for toluene-degradation activity in serum bottles. Only 15% of colonies were true toluene degraders. This population was divided into 11 genotypic groups based on DNA fingerprints. Identification of a member of each group using 16S rRNA gene-sequence comparison showed that they belonged to seven genera: Acinetobacter, Azoarcus, Mycobacterium, Nevskia, Pseudomonas, Pseudonocardia and Rhodococcus. Together, members of the genera Pseudonocardia and Rhodococcus were 34 times more numerous than all the others. We hypothesized that these two organisms are K-strategists (adapted to a resource-restricted and crowded environment) and that the compost biofilter is a K-environment. This would explain why they are not outnumbered by faster growers like Pseudomonas or Acinetobacter species, which would be r-strategists (adapted to a resource-abundant and uncrowded environment). [ABSTRACT FROM AUTHOR]

Presents information on a study which investigates the distribution, histology and secretion types of gonopod tegumental glands (GTG) discovered in six additional brachyuran species. Methodology of the study; Results and discussion.

Objectives: Our main purpose was to investigate any relationship between noise exposure levels in the workplace, degree of hearing loss (HL), and the relative risk of accident (OR of single or multiple events). Methods: We conducted a retrospective study of 52 982 male workers aged 16-64 years with long-standing exposures to occupational noise over a 5-year period, using "hearing status" and "noise exposure" from the registry held by the Quebec National Institute of Public Health. Information on work-related accidents was obtained from the Quebec Workers' Compensation Board. Hearing threshold level measurements and noise exposures were regressed on the numbers of accidents after adjusting for age. Results: Exposure to extremely noisy environments (Leq8h (equivalent noise level for 8 h exposure) ⩾90 dBA) is associated with a higher relative risk of accident. The severity of hearing impairment (average bilateral hearing threshold levels at 3, 4 and 6 kHz) increases the relative risk of single and multiple events when threshold levels exceed 15 dB of hearing loss. The relative risk of multiple events (four or more) is approximately three times higher among severely hearing-impaired workers who are exposed to Leq8h ⩾90 dBA. Conclusion: Single and multiple events are associated with high noise exposure and hearing status. This suggests that reducing noise exposure contributes to increased safety in noisy industries and prevents hearing loss. Hearing-impaired workers assigned to noisy workstations should be provided with assistive listening devices and efficient communication strategies should be implemented. [ABSTRACT FROM AUTHOR]