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Estimating ages of individuals in fish populations is crucial for determining characteristics necessary to effectively manage sport fisheries. Currently, the most accepted approach for fish age determination is using thin sectioned otoliths for interpretation. This method is labor-intensive, requires extensive training, and subjectively determines age. Several studies have shown that otolith mass increases with age, yet use of otolith mass to determine fish age is relatively underutilized. However, determining fish age using otolith mass requires relatively little training, is relatively nonsubjective, and is faster compared with other aging techniques. We collected kokanee salmon (i.e., landlocked sockeye salmon, Oncorhynchus nerka) in 2004 from four reservoirs and from 2000 to 2009 in one reservoir to evaluate the efficacy of using otolith mass to determine fish ages. We used a machine learning technique to predict kokanee salmon ages using otolith mass and various other covariates. Our findings suggest this method has potential to substantially reduce time and financial resources required to age fish. We conclude that using otolith mass to determine fish age may represent an efficient and accurate approach for some species. L'estimation de l'age des individus au sein de populations de poissons est essentielle a la determination de caracteristiques necessaires a une gestion efficace de la peche sportive. La methode de determination de l'age des poissons la plus largement acceptee a l'heure actuelle repose sur l'interpretation de lames minces d'otolithes. Il s'agit d'une methode laborieuse qui necessite une formation poussee et qui etablit l'age de maniere subjective. Si plusieurs etudes ont demontre que la masse des otolithes augmente avec l'age, l'utilisation du poids des otolithes pour determiner l'age des poissons demeure une approche relativement sous-utilisee. Pourtant, cette methode necessite une formation relativement peu poussee et est moins subjective et plus rapide que d'autres methodes de determination de l'age. Nous avons preleve des saumons rouges (Oncorhynchus nerka) de quatre reservoirs en 2004 et d'un reservoir de 2000 a 2009 dans le but d'evaluer l'efficacite d'utiliser le poids des otolithes pour determiner l'age des poissons. Nous avons fait appel a une technique d'apprentissage automatique pour predire l' age de saumons rouges a partir du poids des otolithes et de diverses autres covariables. Nous resultats suggerent que cette methode pourrait permettre des reductions significatives du temps et des ressources financieres necessaires pour determiner l'age de poissons. Nous concluons que cette methode constitue une approche efficiente et exacte de determination de l' age des poissons pour certaines especes. [Traduit par la Redaction], Introduction Fish age interpretation is often an essential component of stock assessments and subsequent management of valuable fisheries globally (Francis and Campana 2004). Currently, the most commonly used methods to [...]

Altering food web structure has been shown to influence mercury (Hg) concentrations in sport fish. Here, we describe a whole-system manipulation designed to assess the effectiveness of stocking relatively high-quality, low-Hg prey (rainbow trout, Oncorhynchus mykiss) as a means of increasing northern pike (Esox lucius) growth to reduce Hg concentrations. A replicated pond experiment served as a reference for the lake experiment and provided information to parameterize bioenergetics simulations. Results indicate that stocking relatively high-quality, low-Hg prey is a rapid and effective method to reduce sport fish Hg concentrations by up to 50% through an increase in individual northern pike biomass. Large northern pike, the fish that tend to be the most contaminated, were affected most by the manipulation. The observed declines in northern pike Hg concentrations indicate that stocking might be used to reduce Hg concentrations in sport fish prior to harvest. However, after 1 year, northern pike Hg concentrations rebounded, suggesting that reductions would be temporary without continuous stocking. Thus, perhaps the most effective method of perpetually reducing sport fish Hg concentrations would be to manage for the development of a naturally reproducing forage fish population with relatively high energy content and low Hg concentrations. On a demontre que la modification du reseau alimentaire influence les concentrations de mercure (Hg) chez les poissons d'interet sportif. Nous decrivons ici une manipulation a l'echelle du systeme entier destinee a evaluer l'efficacite d'un empoissonnement de truites arc-en-ciel (Oncorhynchus mykiss) de qualite relativement elevee se nourrissant de proies a faible teneur en Hg comme moyen d' augmenter la croissance des grands brochets (Esox lucius) afin de reduire leur concentration de Hg. Une experience conduite en double en etang a servi de temoin pour l'experience en lac et a fourni les renseignements necessaires pour determiner les parametres des simulations bioenergetiques. Les resultats indiquent que l' empoissonnement de poissons de qualite relativement elevee et a proies a faible teneur en Hg est une methode rapide et efficace de reduire les concentrations de Hg chez les poissons sportifs de jusqu'a 50 %, par le moyen d'une augmentation de la biomasse individuelle des grands brochets. Les grands brochets de taille superieure, soit les poissons qui ont tendance a etre le plus contamines, sont les plus affectes par la manipulation. Les declins observes dans les concentrations d'Hg chez le grand brochet indiquent que l'empoissonnement peut servir a reduire les concentrations d'Hg chez les poissons sportifs avant la recolte. Cependant, apres une annee, les concentrations d'Hg chez le grand brochet remontent, indiquant que les reductions seraient temporaires sans un empoissonnement continu. Ainsi, la methode la plus efficace de reduire de maniere permanente les concentrations d'Hg chez les poissons sportifs serait peut-etre d'amenager l'etablissement d'une population de poissons fourrage a relativement fort contenu energetique et a faible concentration d'Hg qui se reproduirait naturellement. [Traduit par la Redaction], Introduction Mercury (Hg) contamination in fish is a worldwide concern to human and ecosystem health (Bodaly et al. 1993; Johnston et al. 2003; Kamman et al. 2005). Recently, the potential [...]

In recent years, linguistic research has been focusing more on the analysis of language usage from various sperspectives. Among those approaches, the socio pragmatic one regards language usage as a real, immediate ephenomenon affected by social context in a given situation. The sestudiesincludethoseon verbal politeness, and also on it so ther face, i.e., impoliteness, violence and aggressiveness, which in creasing levels have fortunately been accompanied by more research on them. A vast number of researchers of the Spanish language have conducted studies on the characteristics of such utterances and the variations in their use through out different regions of the Hispanic world. This paper aims to analyze, from the conversation al analysis perspective, the use of violent forms of address by speakers of the borough of Distrito José Martí Sur A and B; thus, contributing to the study of language usage in the Eastern region. [ABSTRACT FROM AUTHOR]

Andrew N de la Torre,1,2 Sohail Contractor,3 Ismael Castaneda,1 Charles S Cathcart,4 Dolly Razdan,5 David Klyde,3 Piotr Kisza,3 Sharon F Gonzales,3 Andres M Salazar6 1Department of Surgery, St Joseph’s Regional Medical Center, Paterson, 2Department of Surgery, Rutgers New Jersey Medical School-University Hospital, 3Department of Interventional Radiology, Rutgers New Jersey Medical School-University Hospital, 4Department of Radiation Oncology, Beth Israel Medical Center, Newark, 5Department of Radiation Oncology, Clara Maas Hospital, Belleville, NJ, 6Oncovir, Washington, DC, USA Purpose: To determine the safety of an approach to immunologically enhance local treatment of hepatocellular cancer (HCC) by combining nonlethal radiation, local regional therapy with intratumoral injection, and systemic administration of a potent Toll-like receptor (TLR) immune adjuvant. Methods: Patients with HCC not eligible for liver transplant or surgery were subject to: 1) 3 fractions of 2-Gy focal nonlethal radiation to increase tumor antigen expression, 2) intra-/peri-tumoral (IT) injection of the TLR3 agonist, polyinosinic-polycytidylic acid polylysine carboxymethylcellulose (poly-ICLC), to induce an immunologic “danger” response in the tumor microenvironment with local regional therapy, and 3) systemic boosting of immunity with intramuscular poly-ICLC. Primary end points were safety and tolerability; secondary end points were progression-free survival (PFS) and overall survival (OS) at 6 months, 1 year, and 2 years. Results: Eighteen patients with HCC not eligible for surgery or liver transplant were treated. Aside from 1 embolization-related severe adverse event, all events were ≤grade II. PFS was 66% at 6 months, 39% at 12 months, and 28% at 24 months. Overall 1-year survival was 69%, and 2-year survival 38%. In patients 60 years (P