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Introduction: Streptococcus pyogenes is a Gram-positive pathogen that causes a significant global burden of skin pyoderma and pharyngitis. In some cases, infection can lead to severe invasive streptococcal diseases. Previous studies have shown that IL-17 deficiency in mice (IL-17-/-) can reduce S. pyogenes clearance from the mucosal surfaces. However, the effect of IL-17 on the development of severe invasive streptococcal disease has not yet been assessed. Methods: Here, we modeled single or repeated non-lethal intranasal (IN) S. pyogenes M1 strain infections in immunocompetent and IL-17-/- mice to assess bacterial colonization following a final IN or skin challenge. Results: Immunocompetent mice that received a single S. pyogenes infection showed long-lasting immunity to subsequent IN infection, and no bacteria were detected in the lymph nodes or spleens. However, in the absence of IL-17, a single IN infection resulted in dissemination of S. pyogenes to the lymphoid organs, which was accentuated by repeated IN infections. In contrast to what was observed in the respiratory mucosa, skin immunity did not correlate with the systemic levels of IL-17. Instead, it was found to be associated with the activation of germinal center responses and accumulation of neutrophils in the spleen. Discussion: Our results demonstrated that IL-17 plays a critical role in preventing invasive disease following S. pyogenes infection of the respiratory tract. [ABSTRACT FROM AUTHOR]

Hook-and-line surveys can be used to estimate population trends in fish species where conventional methods such as trawl, acoustic, visual, or pot surveys cannot be applied. Hook-and-line surveys allow for the collection of biological information, but the resultant indices of abundance may be biased. We designed simulations to address concerns around survey design, hook saturation, and competition among species and found that catch per unit effort (CPUE) declined more slowly than population size across all scenarios. This hyperstability was most prominent when fish were found in high-density patches, and these scenarios have median absolute relative error values roughly three to five times greater than those with more even distributions of fish density. Despite hyperstability, the surveys still had statistical power to detect changes in abundance. Interspecific competition for hooks caused bias in survey results when one species was more aggressive than another. Taken together, our results indicate hook-and-line surveys fill a niche in survey methodologies, but their use and interpretation can be challenged by hyperstability and competition among species.Les releves a la ligne peuvent etre utilises pour estimer les tendances demographiques d'especes de poissons quand des methodes traditionnelles comme les releves acoustiques, visuels, au chalut et au casier ne peuvent etre employees. Si les releves a la ligne permettent la collecte de renseignements biologiques, les indices d'abondance en decoulant peuvent etre biaises. Nous avons conqu des simulations pour examiner les problemes potentiels entourant la conception des releves, la saturation des hameqons et la concurrence entre especes et avons constate que les captures par unite d'effort (CPUE) baissent plus lentement que la taille de la population pour tous les scenarios. Cette hyperstabilite est la plus prononcee quand les poissons se trouvent dans des groupements de haute densite, ces scenarios presentant des valeurs absolues medianes de l'erreur relative environ trois a cinq fois superieures aux valeurs associees a des repartitions plus uniformes de la densite de poissons. Malgre l'hyperstabilite, les releves ont la capacite statistique de detecter des variations d'abondance. La concurrence entre especes pour les hameqons cause un biais dans les resultats des releves quand une espece est plus agressive qu'une autre. Collectivement, nos resultats indiquent que les releves a la ligne ont leur place parmi les methodes de releve, mais que l'hyperstabilite et la concurrence entre especes peuvent compliquer leur utilisation et l'interpretation des resultats qui en decoulent. [Traduit par la Redaction], IntroductionFisheries management is predicated on surveys that monitor changes in population levels. Biased and imprecise surveys can lead to uncertain population estimates that can complicate management strategies. In some cases, [...]

Objective: To investigate physical activity among older people living alone in Shanghai, People's Republic of China, and key factors contributing to their physical activity. Methods: A cross-sectional questionnaire survey was administered in nine communities in Shanghai, using a stratified random cluster sample: 521 community-dwelling older people living alone (aged 60 years and above) completed a structured questionnaire through face-to-face interviews. Their physical activity was measured using their self-reported frequency of engaging in different types of activities. Other data collected included self-rated health, number of chronic diseases, depression, functional ability, loneliness, social support and socio-demographic variables. Results: Only 16.7% of participants reported adequate physical activity, defined as performing at least 30 minutes of moderate/strenuous exercise on at least 5 days per week. A younger age, a lower level of education, better functional ability and walking outside the home 5-7 days per week increased the likelihood of adequate physical activity. Gender, self-rated health, number of chronic diseases, depression and social support also had relationships with physical activity levels. Conclusion: The prevalence of adequate physical activity in older people living alone in Shanghai was low. In this population, appropriate health education interventions to promote physical activity levels are needed.

Pacific Halibut Hippoglossus stenolepis captured in directed commercial longline fisheries in Canada and the USA that are below the legal minimum size for retention must be returned to the sea without incurring additional injury. Estimates of mortality caused by discarding sublegal‐sized fish are included in annual estimates of total mortality from all sources and affect the results of stock assessment and the yield available to fisheries. Currently, an average discard mortality rate (DMR) of 16% is applied to all sublegal‐sized longline discards. These discards consist of fish that suffer injuries ranging from minor to severe. The 16% DMR that is currently applied was derived by averaging injury‐specific DMRs that in turn assume 3.5% mortality of Pacific Halibut that are released to the sea with only minor injuries. The latter has been derived experimentally but only in captivity. Here, we used acceleration‐logging pop‐up archival transmitting tags to infer individual survival outcomes for Pacific Halibut that were released in situ following capture on longline gear. Postrelease behavioral data were evaluated for 75 fish that were at liberty for 2–96 d. Three fish were confidently inferred to have died after periods at liberty of 41–80 d, and another three fish may have died 96 d after release, resulting in minimum and maximum estimated 96‐d postrelease DMRs of 4.2% (range = 0.0–8.7%) and 8.4% (range = 1.7–14.6%), respectively. These ranges are consistent with the currently applied value of 3.5%. However, the observation that no mortalities occurred until after 40 d postrelease departs from the findings of captive studies, in which the majority of capture‐induced mortality occurred within 20 d of release. [ABSTRACT FROM AUTHOR]

The article presents a study which aims to determine the physical activity of older people living alone in Shanghai, China. The study gathered data using a cross-sectional questionnaire survey and measured the physical activity using a self-reported frequency. Result shows that there has been a poor prevalence rate of physical activity on older people living alone in China.

Biological processes such as fishery selectivity, natural mortality, and somatic growth can vary over time, but it is challenging to estimate the magnitude of time-variation of demographic parameters in population dynamics models, particularly when using penalized-likelihood estimation approaches. Random-effect approaches can estimate the variance, but are computationally infeasible or not implemented for many models and software packages. We show that existing models and software based on penalized-likelihood can be used to calculate the Laplace approximation to the marginal likelihood of parameters representing variability over time, and specifically demonstrate this approach via application to Stock Synthesis. Using North Sea cod and Pacific hake models as case studies, we show that this method has little bias in estimating variances for simulated data. It also provides a similar estimate of variability in hake recruitment (log-SD = 1.43) to that obtained from Markov chain Monte Carlo (MCMC) methods (log-SD = 1.68), and the method estimates a non-trivial magnitude (log-SD = 0.07) of variation in growth for North Sea cod. We conclude by discussing the generality of the proposed method and by recommending future research regarding its performance relative to MCMC, particularly when estimating multiple variances simultaneously. [ABSTRACT FROM PUBLISHER]

The article offers information on the Pacific Symphonic Wind Ensemble (PSWE), a group of skilled amateur and professional musicians, which represented the Canada at the World Association of Symphonic Bands and Ensembles (WASBE) conference in Singapore and San Jose, California. It mentions several notable soloist appeared in the concert including clarinetists Mary Backun, Eddie Daniels, and Tom Puwalski.