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Woven polymer-based composites exhibit highly non-linear behavior, which often results in very high strains to failure. A micromechanical model is developed to represent the large deformation kinematics of woven composites, and develop predictions for failure strain components in specific cases of multiaxial loading. Failure functions are proposed for macromechanical analyses of arbitrary cases of large deformation loading. The approach is validated against basic tension experiments performed using both digital image correlation and with specially designed instrumentation for large strain measurement. Predicted failure strains correspond well with experimental observations. The proposed failure functions are well suited for finite element applications involving user-defined material models.

Abstract Background Legionella pneumophila is increasingly recognised as a significant cause of sporadic and epidemic community-acquired and nosocomial pneumonia. Many studies describe the frequency and severity of Legionella spp. contamination in spa pools, natural pools, hotels and ships, but there is no study analysing the environmental monitoring of Legionella on board trains. The aims of the present study were to conduct periodic and precise environmental surveillance of Legionella spp. in water systems and water tanks that supply the toilet systems on trains, to assess the degree of contamination of such structures and to determine the effectiveness of decontamination. Methods A comparative pre-post ecological study was conducted from September 2006 to January 2011. A total of 1,245 water samples were collected from plumbing and toilet water tanks on passenger trains. The prevalence proportion of all positive samples was calculated. The unpaired t-test was performed to evaluate statistically significant differences between the mean load values before and after the decontamination procedures; statistical significance was set at p ≤ 0.05. Results In the pre-decontamination period, 58% of the water samples were positive for Legionella. Only Legionella pneumophila was identified: 55.84% were serogroup 1, 19.03% were serogroups 2–14 and 25.13% contained both serogroups. The mean bacterial load value was 2.14 × 103 CFU/L. During the post-decontamination period, 42.75% of water samples were positive for Legionella spp.; 98.76% were positive for Legionella pneumophila: 74.06% contained serogroup 1, 16.32% contained serogroups 2–14 and 9.62% contained both. The mean bacterial load in the post-decontamination period was 1.72 × 103 CFU/L. According to the t-test, there was a statistically significant decrease in total bacterial load until approximately one and a half year after beginning the decontamination programme (p = 0.0097). Conclusions This study indicates that systematic environmental surveillance could be a useful approach for assessing the risk of exposure to Legionella bacteria, which still represents a public health threat. According to the study results, an environmental surveillance programme, followed by decontamination procedures where necessary, would decrease the total bacterial count, protecting the health of travellers and workers.

Research on the efficacy of innovative, ecofriendly biostimulants in sport turf management is scarce, with less information available from open-field experiments, and even less pertaining to thatch control-related problems. The objective was to investigate the open-field effectiveness of a commercial product, EM-1, and two newly developed products, ExpA and ExpB, in improving both rhizosphere and turfgrass, Agrostis stoloniferous L., characteristics on a golf green. ExpA and ExpB, identical in microbial composition, were equally effective in significantly increasing chlorophyll synthesis and visual turf quality, as well as in resistance to tearing out, compared to the untreated control 56 days after treatment (DAT). EM-1 showed intermediate trends between the control and novel biostimulants. The inclusion of humic acids and mycorrhizal fungi to the microbial composition in ExpB significantly improved some rhizosphere properties 56 DAT relative to the control. Results on ExpB evidenced a significant decrease in the thatch layer thickness and fresh leaf weight, associated with a significant increase in the humus thickness, organic matter decomposition and evapotranspiration efficiency. An increased dry leaf biomass was also shown. ExpA and EM-1 showed either marginal or intermediate improvements relative to the control. ExpB represents a promising alternative to alleviate negative environmental impacts associated with turf maintenance-related activities.