L’opinion publique canadienne sur les changements climatiques et les politiques de contrôle des émissions de gaz à effet de serre

Notes d'analyse de la Chaire d’études politiques et économiques américaines

Gambling behind bars : does prison provide ideal conditions?

While studies exist on the gambling habits of the correctional population prior to incarceration, little information exists on gambling habits during imprisonment. This article aims to describe gambling practices in Quebec prisons. The impact of prison life on these activities and their meaning will be analyzed, relying on semistructured interviews with 51 men currently detained in three federal penitentiaries in Quebec. Contrary to our expectations, the regulations prohibiting gambling in Correctional Service of Canada institutions do not present a central obstacle to this practice. In fact, participation in gambling is limited more by elements connected to the detention institution and the sentence. The availability of certain games, more particularly card games such as poker, as well as the pleasure resulting from those games seem considerably limited in comparison with group bets like sports pools.

A single amino acid substitution in the mRNA capping enzyme λ2 of a mammalian orthoreovirus mutant increases interferon sensitivity.

In the last few years, the development of a plasmid-based reverse genetics system for mammalian reovirus has allowed the production and characterization of mutant viruses. This could be especially significant in the optimization of reovirus strains for virotherapeutic applications, either as gene vectors or oncolytic viruses. The genome of a mutant virus exhibiting increased sensitivity to interferon was completely sequenced and compared with its parental virus. Viruses corresponding to either the parental or mutant viruses were then rescued by reverse genetics and shown to exhibit the expected phenotypes. Systematic rescue of different viruses harboring either of the four parental genes in a mutant virus backbone, or reciprocally, indicated that a single amino acid substitution in one of λ2 methyltransferase domains is the major determinant of the difference in interferon sensitivity between these two viruses.

Further characterization and determination of the single amino acid change in the tsI138 reovirus thermosensitive mutant

Many temperature-sensitive mutants have been isolated in early studies of mammalian reovirus. However, the bio- logical properties and nature of the genetic alterations remain incompletely explored for most of these mutants. The mutation harbored by the tsI138 mutant was already assigned to the L3 gene encoding the l1 protein. In the present study, this mu- tant was further studied as a possible tool to establish the role of the putative l1 enzymatic activities in viral multiplication. It was observed that synthesis of viral proteins is only marginally reduced, while it was difficult to recover viral particles at the nonpermissive temperature. A single nucleotide substitution resulting in an amino acid change was found; the position of this amino acid is consistent with a probable defect in assembly of the inner capsid at the nonpermissive temperature.

Transient high level mammalian reovirus replication in a bat epithelial cell line occurs without cytopathic effect

Mammalian reoviruses exhibit a large host range and infected cells are generally killed; however, most studies examined only a few cell types and host species, and are probably not representative of all possible interactions between virus and host cell. Many questions thus remain concerning the nature of cellular factors that affect viral replication and cell death. In the present work, it was observed that replication of the classical mammalian reovirus serotype 3 Dearing in a bat epithelial cell line, Tb1.Lu, does not result in cell lysis and is rapidly reduced to very low levels. Prior uncoating of virions by chymotrypsin treatment, to generate infectious subviral particles, increased the initial level of infection but without any significant effect on further viral replication or cell survival. Infected cells remain resistant to virus reinfection and secrete an antiviral factor, most likely interferon, that is protective against the unrelated encephalomyocarditis virus. Although, the transformed status of a cell is believed to promote reovirus replication and viral “oncolysis”, resistant Tb1.Lu cells exhibit a classical phenotype of transformed cells by forming colonies in semisolid soft agar medium. Further transduction of Tb.Lu cells with a constitutively-active Ras oncogene does not seem cell growth or reovirus effect on these cells. Infected Tb1.Lu cells can produce low-level of infectious virus for a long time without any apparent effect, although these cells are resistant to reinfection. The results suggest that Tb1.Lu cells can mount an unusual antiviral response. Specific properties of bat cells may thus be in part responsible for the ability of the animals to act as reservoirs for viruses in general and for novel reoviruses in particular. Their peculiar resistance to cell lysis also makes Tb1.Lu cells an attractive model to study the cellular and viral factors that determine the ability of reovirus to replicate and destroy infected cells.

Amino acid substitutions in σ1 and μ1 outer capsid proteins are selected during mammalian reovirus adaptation to Vero cells

Establishment of viral persistence in cell culture has previously led to the selection of mammalian reovirus mutants, although very few of those have been characterized in details. In the present study, reovirus was adapted to Vero cells that, in contrast to classically-used L929 cells, are inefficient in supporting the early steps of reovirus uncoating and are also unable to produce interferon as an antiviral response once infection occurs. The Vero cell-adapted reovirus exhibits amino acids substitutions in both the σ1 and μ1 proteins. This contrasts with uncoating mutants from persistently-infected L929 cells, and various other cell types, that generally harbor amino acids substitutions in the σ3 outer capsid protein. The Vero cell-adapted virus remained sensitive to an inhibitor of lysosomal proteases; furthermore, in the absence of selective pressure for its maintenance, t he virus has partially lost its ability to resist interferon. The positions of the amino acids substitutions on the known protein structures suggest an effect on binding of the viral σ1 protein to the cell surface and on μ1 disassembly from the outer capsid.

Addition of exogenous polypeptides on the mammalian reovirus outer capsid using reverse genetics

Addition of exogenous peptide sequences on viral capsids is a powerful approach to study the process of viral infection or to retarget viruses toward defined cell types. Until recently, it was not possible to manipulate the genome of mammalian reovirus and this was an obstacle to the addition of exogenous sequence tags onto the capsid of a replicating virus. This obstacle has now been overcome by the advent of the plasmid-based reverse genetics system. In the present study, reverse genetics was used to introduce different exogenous peptides, up to 40 amino acids long, at the carboxyl-terminal end of the σ1 outer capsid protein. The tagged viruses obtained were infectious, produce plaques of similar size, and could be easily propagated at hight titers. However, attempts to introduce a 750 nucleotides-long sequence failed, even when it was added after the stop codon, suggesting a possible size limitation at the nucleic acid level.

Amino acids substitutions in σ1 and μ1 outer capsid proteins of a Vero cell-adapted mammalian orthoreovirus are required for optimal virus binding and disassembly

In a recent study, the serotype 3 Dearing strain of mammalian orthoreovirus was adapted to Vero cells; cells that exhibit a limited ability to support the early steps of reovirus uncoating and are unable to produce interferon as an antiviral response upon infection. The Vero cell-adapted virus (VeroAV) exhibits amino acids substitutions in both the σ1 and μ1 outer capsid proteins but no changes in the σ3 protein. Accordingly, the virus was shown not to behave as a classical uncoating mutant. In the present study, an increased ability of the virus to bind at the Vero cell surface was observed and is likely associated with an increased ability to bind onto cell-surface sialic acid residues. In addition, the kinetics of μ1 disassembly from the virions appears to be altered. The plasmid-based reverse genetics approach confirmed the importance of σ1 amino acids substitutions in VeroAV's ability to efficiently infect Vero cells, although μ1 co-adaptation appears necessary to optimize viral infection. This approach of combining in vitro selection of reoviruses with reverse genetics to identify pertinent amino acids substitutions appears promising in the context of eventual reovirus modification to increase its potential as an oncolytic virus.

Engaging Ethical Issues Associated with Research and Public Health Interventions During Humanitarian Crises: Review of a Dialogic Workshop

Compte-rendu / Review

Four Stages In Assessing Liberal Neutrality

La notion de neutralité, bien que référent central au sein d’un État libéral, est souvent invoquée de manière imprécise et contradictoire dans le discours public. Proposant que cela résulte en partie des limites inhérentes à une compréhension abstraite et uniforme de ce concept, le présent article exposera comment l’idéal de neutralité libérale doit plutôt s’inscrire et s’évaluer par le biais de quatre étapes successives. Les quatre étapes en question dépassent la simple herméneutique philosophique du libéralisme en trouvant déjà des assises dans le droit ; elles seront dès lors illustrées tout au long du texte à l’aide des décisions pertinentes de la Cour Suprême du Canada.

L’opinion des Canadiens et des Américains au sujet des changements climatiques: un écart important?

Cette note présente des résultats de deux importants sondages menés en parallèle dans les deux pays. Au Canada, nos données sont tirées du plus récent Canadian Survey on Energy and the Environment (CSEE, Lachapelle et al. 2015) et aux États-Unis, nous rapportons les résultats du National Survey on Energy and the Environment (NSEE). Réalisés au mois de septembre 2015, ces deux sondages ont soumis les mêmes questions à des échantillons représentatifs des populations du Canada et des États-Unis.

Les seules règles de droit qui peuvent poser des limites aux droits et libertés constitutionnellement protégés et l'arrêt Slaight Communications

Cet article de Danielle Pinard a précédemment été publié par la Revue nationale de droit constitutionnel. Reproduit avec l’autorisation de Carswell, une société de Thomson Reuters Canada limitée.

Policía y seguridad ciudadana en Canadá: de la fantasía de Disney a la represión

La Real Policía Montada (Royal Ca­nadian Mounted Police o Gendarmerie Royale du Canada) es quizás el primer y más importante ícono de la nacionalidad canadiense en un país cuyos símbolos patrios fueron creados recientemente después de la década de 1960. Mientras la Real Montada fue fundada en 1864, la tradicional bandera canadiense con la hoja del arce fue adoptada en 1964 y el himno nacional en 1980. Así, creció de la mano de la joven nación y aseguró la colonización hacia el oeste procurando la soberanía para la confederación que se inició en el siglo XIX. Esta institución hace parte de la iconografía de Canadá gracias a cientos de cuentos infantiles, tiras cómicas, películas y series de televisión que hicieron de esta policía un símbolo de orgullo, honestidad y devoción. El mítico sargento King de las tiras cómicas o la película que prota­gonizara Shirley Temple Susannah of the Mounties catapultaron esta idea positiva de la policía canadiense hasta el punto que Disney compró por algunos años los dere­chos del famoso uniforme de casaca roja, pantalón azul marino con raya amarilla y el sombrero de ala ancha y plana. Sin embargo, el panorama de la policía en Canadá es más complejo del que a sim­ple vista representa esta imagen idílica. La coexistencia de diferentes cuerpos de po­licía, las actividades encubiertas en contra de los independentistas quebequéses o los intentos frustrados por implementar algu­nas reformas en las políticas de seguridad son la otra cara de la moneda. Aun así, en términos estadísticos la policía canadien­se es una de las mejores dotadas, pagas y organizadas en el mundo. Los índices delincuenciales y los sentimientos de inse­guridad son bajos y una doble estrategia de inversión social y gasto en seguridad ciu­dadana y orden público han dado réditos tangibles. Este artículo pretende dibujar una síntesis de la policía y la seguridad ciudadana en Canadá señalando las con­tradicciones y desajustes de su evolución así como los logros alcanzados. 

Aproximación al manejo de la seguridad ambiental canadiense y estadounidense frente a la degradación del sistema de la los Grandes Lagos. Periodo 1995-2000

El propósito de la presente monografía es determinar la relación entre la degradación y navegación en los Grandes Lagos en la noción de seguridad ambiental de Estados Unidos y Canadá en un entorno de interdependencia entre 1995 - 2000. En ese sentido, se busca determinar como los recursos de poder de Canadá y Estados Unidos en la relación degradación-navegación transforma la noción de seguridad ambiental. De este modo, se analiza el concepto de seguridad ambiental desde la navegación, elemento esencial para entender la relación bilateral dentro del sistema de los Grandes Lagos. Esta investigación de tipo cualitativo que responde a las variables de la seguridad ambiental planteadas por Barry Buzan, Thomas Homer-Nixon, y Stephan Libiszewski, y a la teoría de la Interdependencia Compleja por Robert Keohane y Joseph Nye, pretende avanzar hacia la complejización de la dimensión ambiental lejos de la tradicional definición antropocéntrica.

Seguros de desempleo: revisión de literatura y propuesta para Colombia

En este artículo se estudia la posibilidad de introducir seguros de desempleo en Colombia. En una primera parte, se propone una revisión de literatura de los seguros de desempleo en la cual se exponen las ventajas generadas por una cobertura contra este riesgo, así como sus inconvenientes. En una segunda parte, se estudian varios escenarios para introducir seguros de desempleo en Colombia. Después de haber presentado el contexto del mercado laboral y de las normas que lo vigilan, se proponen varios diseños que abordan la gestión y la administración del riesgo de desempleo en Colombia. Igualmente se presentan algunas consideraciones teóricas para la valoración del costo del aseguramiento, las cuales incorporan los efectos del riesgo moral sobre la duración y la incidencia del desempleo.