Rationale: Peak initiation of smoking occurs during adolescence and early onset of smoking is associated with a reduced probability of quitting and greater risk of relapse compared to later onset. Considering the epidemiological evidence, adolescents may exhibit a unique biological susceptibility to nicotine taking, in addition to the behavioural and psychosocial factors known to influence adolescent smoking. Objectives: The current series of experiments, using a rat model of adolescent nicotine taking, was designed to investigate age differences in the processes involved in the acquisition and maintenance of nicotine taking that might account for the elevated initiation rates of smoking during adolescence. Methods: We first investigated age differences in the neural response to acute nicotine administration using c-fos mRNA expression. We then examined age differences in the rewarding and aversive effects of nicotine in the conditioned place preference (CPP) and conditioned taste avoidance (CTA) paradigms, respectively. The direct reinforcing effects of nicotine were tested in adolescent and adult rats under a variety of reinforcement schedules in the operant intravenous self-administration paradigm; extinction and nicotine priming-induced reinstatement were also examined. Finally, age differences in nicotine withdrawal precipitated by mecamylamine were assessed. Results: Nicotine had greater activational effects on c-fos mRNA expression in reward-related neural substrates of adolescent compared to adult brain. Adolescent rats were also more sensitive to the rewarding effects of nicotine (CPP) yet less sensitive to its aversive effects (CTA) compared to adult rats. Nicotine was equally reinforcing in adolescents and adults self-administering under simple reinforcement schedules, but adults were more motivated to obtain nicotine under higher reinforcement schedules. Adults were more resistant to extinction, yet both age groups demonstrated similar priming-induced reinstatement of nicotine seeking. Under spontaneous acquisition conditions, adults were more sensitive to the reinforcing effects of a low nicotine infusion dose. The aversive effects of nicotine withdrawal were also more prominent in adults compared to adolescents. Conclusions: These findings have important implications since they demonstrate a unique susceptibility to the conditioned rewarding effects of nicotine that would promote acquisition of smoking behaviour during adolescence, whereas adults may be more vulnerable to processes involved in its maintenance.

After a conceptual overview of the scope of the right to job stability, its relationship with other rights (right to work, right to access to employment, right to maintain employment) and its constitutional, international and legal regulation and the position of jurisprudence, the author goes on to discuss the complex picture presented to the employer before a decision to dismiss both from a legal perspective (compensation, replacement) and case law (damages, replacement) adding a paragraph called “others” the recount administrative consequences arising from said measure both labor (SUNAFIL) and tax (SUNAT) viewpoint. / Luego de un breve repaso conceptual de los alcances del derecho a la estabilidad laboral, su relación con otros derechos (derecho al trabajo, derecho de acceso al empleo, derecho a conservar el empleo) y su regulación constitucional, internacional y legal, así como la posición de la jurisprudencia, el autor pasa a comentar el complejo panorama que se presenta al empleador ante una decisión de despido tanto desde la óptica legal (indemnización, reposición) como jurisprudencial (indemnización por daños, reposición) añadiéndose un acápite denominado “otros” para las relatar las consecuencias administrativas que surgen de la indicada medida tanto desde la óptica laboral (SUNAFIL) como tributaria (SUNAT).

Essa dissertação de mestrado apresenta um estudo com os trabalhadores demitidos de uma Empresa Pública, na década de 1990, por força da implementação de medidas neoliberais no Brasil. Apesar dos inúmeros impactos gerados a esses trabalhadores, após esta decisão do Estado, a proposta é analisar os impactos objetivos, sofridos pelos trabalhadores, originários da perda repentina de um contrato de trabalho formal e consequentemente, da perda de salários diretos, de salários indiretos, com a ausência de políticas sociais corporativas, e de direitos garantidos enquanto trabalhadores protegidos. As estratégias de sobrevivência adotadas por estes trabalhadores foram as mais variadas, porém, a grande maioria teve o trabalho por conta própria como a principal alternativa de reprodução social, saindo completamente do ramo de produção em que trabalhavam. Insatisfeitos com a demissão, esse grupo de trabalhadores lutou para retornar ao quadro de empregados da Corporação. Após cerca de uma década e meia, os trabalhadores conquistaram o direito de retornar e ser admitido pela Empresa V, uma das que compõem a Corporação, tendo em vista a extinção daquelas a que pertenciam. Com essa decisão, os trabalhadores e suas famílias estavam novamente assegurados pelas políticas corporativas e com novas possibilidades. No entanto, a adequação aos novos requisitos da Empresa V, fez com que alguns indivíduos não atendessem ao novo perfil de trabalhador exigido pela instituição e pelo mercado de trabalho, devido à idade e ao tipo de qualificação. Assim, ao mesmo tempo em que o retorno lhes trouxe novas possibilidades, com o acesso a um salário mensal e políticas empresariais de qualidade, por outro lado, também trouxe grandes desafios para alguns trabalhadores, devido a sua dificuldade de inserção nos processos de trabalho e nas normas da empresa. Conclui-se então, que o retorno à Corporação, após mais de uma década de luta, foi para esse grupo de trabalhadores, um processo contraditório, pois, ao mesmo tempo em que tiveram diversos direitos assegurados, alguns não conseguiram desenvolver suas atividades nos moldes do atual modo de produção. / This thesis describes a study of workers dismissed from a public company, in the 1990s, under the implementation of neoliberal measures in Brazil. Despite the numerous impacts generated by these workers after the decision of the State, the proposal is to analyze the impacts goals, suffered by workers originating in a sudden loss of formal employment contract and therefore the loss of direct salaries, wages indirect with the absence of corporate social policies, and guaranteed rights as workers protected. The survival strategies adopted by these workers were the most varied, however, most had self-employment as the main alternative of social reproduction and completely out of the industry in which they worked. Dissatisfied with the dismissal, this group of workers struggled to return to the staff of the Corporation. After about a decade and a half, workers won the right to return and be accepted by the Company V, which composes the Corporation in view the extinction of those to which they belonged. With this decision, workers and their families were again assured by corporate policies and new possibilities. However, the adaptation to the new requirements of Company V, meant that some individuals did not meet the new worker profile required by the institution and the labor market. Thus, while the return gave them new opportunities, with access to a monthly salary and company policy of quality, however, also brought great challenges to some workers, due to their difficulty of insertion in the work processes and the standards of the company. It follows then, that the return to the Corporation, after more than a decade of struggle, it was for this group of workers, an adversarial process, because while they had different legal rights, some failed to develop its activities in the manner the current mode of production.

Essa dissertação de mestrado apresenta um estudo com os trabalhadores demitidos de uma Empresa Pública, na década de 1990, por força da implementação de medidas neoliberais no Brasil. Apesar dos inúmeros impactos gerados a esses trabalhadores, após esta decisão do Estado, a proposta é analisar os impactos objetivos, sofridos pelos trabalhadores, originários da perda repentina de um contrato de trabalho formal e consequentemente, da perda de salários diretos, de salários indiretos, com a ausência de políticas sociais corporativas, e de direitos garantidos enquanto trabalhadores protegidos. As estratégias de sobrevivência adotadas por estes trabalhadores foram as mais variadas, porém, a grande maioria teve o trabalho por conta própria como a principal alternativa de reprodução social, saindo completamente do ramo de produção em que trabalhavam. Insatisfeitos com a demissão, esse grupo de trabalhadores lutou para retornar ao quadro de empregados da Corporação. Após cerca de uma década e meia, os trabalhadores conquistaram o direito de retornar e ser admitido pela Empresa V, uma das que compõem a Corporação, tendo em vista a extinção daquelas a que pertenciam. Com essa decisão, os trabalhadores e suas famílias estavam novamente assegurados pelas políticas corporativas e com novas possibilidades. No entanto, a adequação aos novos requisitos da Empresa V, fez com que alguns indivíduos não atendessem ao novo perfil de trabalhador exigido pela instituição e pelo mercado de trabalho, devido à idade e ao tipo de qualificação. Assim, ao mesmo tempo em que o retorno lhes trouxe novas possibilidades, com o acesso a um salário mensal e políticas empresariais de qualidade, por outro lado, também trouxe grandes desafios para alguns trabalhadores, devido a sua dificuldade de inserção nos processos de trabalho e nas normas da empresa. Conclui-se então, que o retorno à Corporação, após mais de uma década de luta, foi para esse grupo de trabalhadores, um processo contraditório, pois, ao mesmo tempo em que tiveram diversos direitos assegurados, alguns não conseguiram desenvolver suas atividades nos moldes do atual modo de produção. / This thesis describes a study of workers dismissed from a public company, in the 1990s, under the implementation of neoliberal measures in Brazil. Despite the numerous impacts generated by these workers after the decision of the State, the proposal is to analyze the impacts goals, suffered by workers originating in a sudden loss of formal employment contract and therefore the loss of direct salaries, wages indirect with the absence of corporate social policies, and guaranteed rights as workers protected. The survival strategies adopted by these workers were the most varied, however, most had self-employment as the main alternative of social reproduction and completely out of the industry in which they worked. Dissatisfied with the dismissal, this group of workers struggled to return to the staff of the Corporation. After about a decade and a half, workers won the right to return and be accepted by the Company V, which composes the Corporation in view the extinction of those to which they belonged. With this decision, workers and their families were again assured by corporate policies and new possibilities. However, the adaptation to the new requirements of Company V, meant that some individuals did not meet the new worker profile required by the institution and the labor market. Thus, while the return gave them new opportunities, with access to a monthly salary and company policy of quality, however, also brought great challenges to some workers, due to their difficulty of insertion in the work processes and the standards of the company. It follows then, that the return to the Corporation, after more than a decade of struggle, it was for this group of workers, an adversarial process, because while they had different legal rights, some failed to develop its activities in the manner the current mode of production.

No description available.

La 3,4-metilendioximetanfetamina (MDMA), una sustancia popularmente conocida como éxtasis, es una droga ilícita consumida habitualmente por adolescentes y adultos jóvenes. Además, el policonsumo es una práctica habitual entre los usuarios de la MDMA, siendo la cocaína una de las drogas más frecuentemente asociadas a esta sustancia. El objetivo del presente trabajo fue evaluar los efectos a corto y largo plazo que se producen tras la administración de la MDMA (5, 10, o 20 mg/kg) sola o en combinación con cocaína (25 mg/kg) en ratones adolescentes. En el estudio sobre el efecto agudo, observamos que ambas drogas administradas individual o simultáneamente incrementan la actividad motora. La dosis alta de MDMA disminuye de los contactos sociales en la prueba de la interacción social afectando igualmente el test de retención de la evitación pasiva. Sin embargo, sólo la co-administración de MDMA en combinación con cocaína produjo un efecto ansiolítico caracterizado por un aumento del tiempo de permanencia en los brazos abiertos del laberinto elevado en cruz. Igualmente, el análisis neuroquímico reveló que los ratones que recibieron MDMA en combinación con cocaína mostraron un incremento en el turnover de DA en el estriado, pero una disminución del de serotonina en la corteza. Los estudios de los efectos a largo plazo, realizados tres semanas después de haber finalizado un tratamiento con MDMA sola o en combinación con cocaína (2 administraciones por día durante 3 días consecutivos), mostraron que los ratones expuestos a la MDMA, sola o más cocaína, incrementaron el tiempo dedicado a las conductas sociales, aunque los que también habían recibido cocaína presentaban además conductas de amenaza. Observamos un efecto neurotóxico en los ratones tratados únicamente con 20 mg/kg de MDMA que mostraron un decremento de la concentración de DA en el estriado, no observándose este deterioro en los tratados además con cocaína. Por otra parte, mediante el condicionamiento de la preferencia de lugar (CPL) confirmamos que la MDMA posee efectos reforzantes y que esta sustancia es capaz de reinstaurar la preferencia de lugar una vez que esta se ha extinguido. La expresión y la reinstauración del CPL inducido por la MDMA dependen de la pauta de condicionamiento que condiciona los efectos neurotóxicos producidos por esta droga. Para finalizar, el tratamiento con MDMA sola o en combinación con cocaína durante la adolescencia favorece los efectos reforzantes de la MDMA durante el periodo adulto. Además, la exposición previa a la cocaína aumenta el tiempo necesario para extinguir la preferencia de lugar inducida por la MDMA. / 3,4-methylene-dioxy-methamphetamine (MDMA), commonly known as ecstasy, is an illicit recreational drug consumed by teenagers and young adults. The poly-drug pattern is the most common among those observed in MDMA users, with cocaine being a frequently associated drug. The aim of the present study was to evaluate the short- and long-term effects of exposure to MDMA (5, 10, or 20 mg/kg), alone or plus cocaine (25 mg/kg), on adolescent mice. In the acute phase, both drugs produced hyperactivity whether administered alone or concurrently. The highest MDMA dose decreased social contacts and affected the passive avoidance task. However, an anxiolytic effect, studied by means of the elevated plus maze and expressed as an increase in the time spent on the open arms, was observed only in animals treated with both cocaine and MDMA. Neurochemical analyses revealed an increase in striatal DA turnover and a decrease in serotonin cortical turnover in mice treated with MDMA plus cocaine. The studies conducted to establish long-term effects, which were performed 3 weeks after a 3-day treatment of two daily injections of MDMA alone or plus cocaine (6 administrations) during the adolescent period, showed that mice treated with MDMA alone and plus cocaine spent more time engaged in social contact, although those also treated with cocaine exhibited threat behaviors. Furthermore, we observed a neurotoxic effect in mice exposed to 20 mg/kg of MDMA, evident in a decrease in DA levels in the striatum, but this effect was not detected in mice additionally treated with cocaine. On the other hand, using the conditioned place preference (CPP), we have confirmed the rewarding effects of MDMA. In addition, we also show that MDMA can produce reinstatement of place preference after the extinction of this response. The expression and reinstatement of MDMA-induced CPP depend on the conditioning protocol, which conditions the neurotoxic effects produced by this drug. Finally, exposure during adolescence to MDMA alone or plus cocaine facilitates the rewarding effects of MDMA in adulthood. Moreover, previous experience of cocaine increases the time required to extinguish the MDMA-induced CPP.

The protection against dismissal in the evolution of the Constitutional Court jurisprudenceThis paper is based on the analysis of the job security schemes embodied in the Constitutions of 1979 and 1993, so as to point out the evolution of the protection granted by the constitutional system against unlawful dismissal and the legal application thereof to the models of restitutory protection (reinstatement) or compensatory protection (indemnification). Then, an analysis is made with respect to the options covered in this field by the international treaties executed by Peru and the evolution of different constitutional case law. Thus, judgments in which restitutory protection was initially oriented to outlaw the dismissal that violates fundamental rights are examined, in comparison to recent rulings in which such protection is granted against unlawful dismissal, resulting in a labor stability model different from the one set forth by the 1993 Constitution. / El presente trabajo parte por analizar los esquemas de estabilidad laboral recogidos en las Constituciones de 1979 y 1993, con el fin de advertir la evolución de la protección otorgada por el ordenamiento constitucional frente al despido ilícito y su plasmación legal en modelos de tutela restitutoria (reposición) o resarcitoria (indemnización). Seguidamente, se evalúan las opciones que sobre esta materia recogen los tratados internacionales suscritos por el Perú para luego tratar la evolución de la jurisprudencia constitucional. Así, se examinan pronunciamientos en que la tutela restitutoria estuvo inicialmente orientada a proscribir el despido que agravie derechos fundamentales, para luego analizar fallos recientes en los que se concede dicha tutela frente al despido injustificado, configurándose, por esta vía, un modelo de estabilidad laboral distinto al establecido por la Constitución de 1993.

Several interesting findings emerged from this study. First, strong labour movements still failed to successfully bargain for employment protections due to resistance from employers to encroachments on their institutionalized managerial prerogatives. Second, governments favoured a policy of abstentionism and acquiescence to the collective-laissez-faire tradition until the critical juncture of the 1960s and 1970s. Third, the increasing power resources of trade unions and a deteriorating socio-economic climate created a window of opportunity for bold government action to improve industrial relations, albeit without the consent of employers, and at first, unions. Fourth, contrary to the liberalizing pressures one would expect to find in an archetypical free market economy, the UK has implemented far more statutory protections than deregulatory reforms. Fifth, in contrast to its traditional non-intervention in industrial relations and reputation for worker-protective regulations, Swedish governments have enacted numerous statutes, both restricting and freeing managerial prerogatives in the hiring and firing process. Sixth, statutory employment protections became an independent set of institutional power resources for unions in the long run, serving their organizational and representational interests in important ways. Seventh, unions and left parties consistently defended and advanced the policy preferences of their core constituencies in secure employment by privileging the job security of regular contracts. Eighth, employers and parties on the right of the political spectrum consistently opposed restrictions on the managerial capacity to hire and fire at will, especially for small businesses. Nineth, to increase flexibility without threatening the stability of regular contracts, reforms over the years had to foster atypical forms of work, creating a regulatory gap between permanent and temporary employment, particularly in Sweden. Tenth, differences exist between job security in the statute books and job security in action, particularly in the UK where this gap pervades all aspects of the unfair dismissal system. These findings suggest employment protection legislation has developed in ways far more complex, dynamic and contradictory than is commonly assumed by prominent theories of comparative political economy. / Dissertation / Doctor of Philosophy (PhD) / This thesis examines how and why employment protection legislation developed in the United Kingdom and Sweden in the ways that it did from its early beginnings to the present period. It hopes to offer answers to questions about the initial impetus for statutory regulation, the number, content and impact of significant legislative changes and the preferences of key stakeholders with material interests in the policymaking process. It does this by drawing on a variety of both primary and secondary source materials, including employment protection databases, parliamentary records and research publications. At the same time, it assesses the explanatory merit of dominant theories in the political economy literature by testing them against voluminous empirical evidence and provides a multi-factorial account to fill the gaps in the existing body of knowledge.

No description available.