RESUMEN: Se informa sobre la presencia de un afloramiento de obsidiana negra previamente desconocido ubicado en el extremo oriental del Macizo del Deseado, en cercanías del océano Atlántico y de la localidad de Tres Cerros, en Patagonia. La obsidiana constituye un vidrio de riolita subalcalina con contenido medio de potasio. Es de menor calidad que la obsidiana negra de la fuente de Pampa del Asador, emplazada en inmediaciones de la cabecera del río Chico, en el noroeste de Santa Cruz. Los datos geoquímicos de ICP-MS e INAA obtenidos para 16 muestras de obsidiana son comparables cuando se consideran las incertidumbres de medición. Sin embargo, éstos son significativamente diferentes a los datos de ICP-MS publicados para muestras procedentes de Pampa del Asador y 17 de Marzo, lo que indica que la obsidiana de Tres Cerros se puede diferenciar geoquímicamente de las mencionadas fuentes secundarias. Se analizó un artefacto de obsidiana negra procedente del sitio Alero 4, ubicado en la costa noreste de Santa Cruz, que presentaba características macroscópicas similares a las identificadas en las muestras de Tres Cerros. Los resultados indicaron que se trataba de una obsidiana procedente de Pampa del Asador. Asimismo, las tendencias geoquímicas obtenidas para las muestras de Tres Cerros no resultaron compatibles con las observadas en artefactos de los sitios Alero del Valle y Cueva Aristizábal, emplazados próximos a la costa sudeste de Santa Cruz. En este sentido, si bien aún no se han registrado evidencias que indiquen la explotación de la fuente Tres Cerros por parte de grupos humanos cazadores-recolectores que ocuparon Patagonia en el pasado, la caracterización geoquímica aquí presentada constituye información que podrá ser comparada con muestras procedentes de sitios arqueológicos ubicados a distintas distancias de ella, contribuyendo de esta manera a entender la movilidad humana en la región, así como los criterios de selección de materias primas.

ABSTRACT: We report a previously unknown black obsidian outcrop located at the eastern end of the Deseado Massif, near the Atlantic Ocean and the town of Tres Cerros, in Patagonia. This obsidian is a subalkaline rhyolite glass with medium potassium content. It is of lower quality than the black obsidian from the Pampa del Asador source, located in the vicinity of the headwaters of the Chico River, in the northwest of Santa Cruz. The ICP-MS and INAA geochemical data obtained for 16 obsidian samples are comparable when measurement uncertainties are considered. However, these are significantly different from published ICP-MS data for samples from Pampa del Asador and 17 de Marzo, indicating that obsidian from Tres Cerros can be differentiated geochemically from these secondary sources. A black obsidian artifact from the Alero 4 site, located on the northeastern coast of Santa Cruz, was analyzed, showing macroscopic characteristics similar to those identified in the Tres Cerros samples. The results indicated that it was an obsidian from Pampa del Asador. Likewise, the geochemical trends obtained for the Tres Cerros samples were not compatible with those observed in artifacts from the Alero del Valle and Cueva Aristizábal sites, located close to the southeast coast of Santa Cruz. In this sense, we emphasize that no evidence has yet been recorded that indicates the exploitation of Tres Cerros source by human hunter-gatherer groups that occupied the Patagonian region in the past. In this framework, the geochemical characterization of the potential source presented here constitutes initial information which can be compared with the one obtained from artifacts in archaeological sites, providing information to understand human mobility and the criteria for raw material selection.

Abstract: The Center for Demographic, Urban and Environmental Studies at El Colegio de México paid tribute to research professor Susana Lerner Sigal for 45 years of outstanding academic career. At the ceremony, her various academic contributions were listed, such as the substantive boost she gave to the development of Mexican socio demography, a task she has always undertaken from an interdisciplinary perspective using an original approach, constructed collectively, which captures the diversity, heterogeneity and social, historical, institutional and cultural inequality that characterize our society. In her unusual career, Susana Lerner has also participated in achieving specific changes in Mexican social reality, such as the state’s recognition and guarantee of fundamental reproductive rights. The Tribute to Susan Lerner Sigal was held on February 24, 2012 in the Alfonso Reyes Hall at El Colegio de México. Silvia Giorguli, Claudio Stern, Carolina Martínez S., Soledad González Montes, Brígida García and Orlandina de Oliveira served as commentators, with Ivonne Szasz as moderator. Lastly, Susana Lerner issued a brief message of thanks. The addresses of each of the speakers are given below, in order of presentation.

Resumen: La profesora investigadora Susana Lerner Sigal cumplió 45 años de destacada trayectoria académica, motivo por el cual el Centro de Estudios Demográficos, Urbanos y Ambientales de El Colegio de México le rindió un homenaje. En dicho acto se realizó un recuento de sus varios aportes académicos, entre los que destaca el sustantivo impulso que dio al desarrollo de la sociodemografía mexicana, labor que siempre ha efectuado desde una perspectiva interdisciplinaria y desde un enfoque original, construido colectivamente, que recupera la diversidad, la heterogeneidad y la desigualdad −social, histórica, institucional y cultural− que caracterizan a nuestra sociedad. En su singular trayectoria, Susana Lerner también participó en el logro de transformaciones concretas de la realidad social mexicana, como es el caso del reconocimiento y la garantía estatal de los derechos reproductivos fundamentales. El Homenaje a Susana Lerner Sigal tuvo lugar el 24 de febrero de 2012 en la Sala Alfonso Reyes de El Colegio de México. Asistieron como comentaristas Silvia Giorguli, Claudio Stern, Carolina Martínez S., Soledad González Montes, Brígida García y Orlandina de Oliveira; fungió como moderadora Ivonne Szasz. Por último, Susana Lerner emitió un breve mensaje de agradecimiento. A continuación reproducimos las palabras de cada uno de los oradores del acto en el orden de su presentación.

O sucesso da cultura do girassol (Helianthus annuus L.) no Brasil está associado à escolha adequada de cultivares com adaptação a diferentes ambientes. Quando há respostas diferenciadas dos genótipos testados nos diferentes ambientes, a decisão de lançamento de novas cultivares pode ser facilitada com estudos de adaptabilidade e estabilidade desses genótipos para reduzir os efeitos da interação genótipos x ambientes. No país, essas informações tornam-se mais importantes, pois a maioria das cultivares utilizadas, ou em lançamento, foram desenvolvidas em outros países, com características de solo e clima diferentes. Este trabalho teve como objetivo estudar a adaptabilidade e estabilidade de genótipos de girassol na região subtropical do Brasil, uma das regiões promissoras do país para o seu cultivo. Os dados foram obtidos da Rede Nacional de Ensaios de Avaliação de Genótipos de Girassol, coordenada pela Embrapa Soja, entre os anos de 1999/2000 e 2003/2004. Os caracteres avaliados foram rendimentos de grãos e de óleo (kg ha-1). Os estudos de adaptabilidade e estabilidade foram realizados segundo as metodologias de PORTO et al. (2007), EBERHART & RUSSELL (1966) e ROCHA et al. (2005), as quais utilizam procedimentos biométricos distintos. Diferente do método de EBERHART & RUSSELL (1966), o de PORTO et al. (2007) selecionou genótipos que, apesar de terem médias gerais inferiores às testemunhas, tiveram bons desempenhos em ambientes específicos. Esse método foi mais rigoroso em selecionar genótipo, em relação ao de ROCHA et al. (2005). Para rendimento de grãos, o genótipo ACA 884 apresentou indicação para ambientes em geral, EM 677008, Agrobel 930 e GV 26048 foram indicados para ambientes favoráveis, e ACA 885, para os desfavoráveis. Para rendimento de óleo, ACA 884 teve indicação geral, GV 26048, CF 17, Agrobel 972 e Helio 358 tiveram indicação para ambientes favoráveis, e HT 01 e ACA 885, para os desfavoráveis.

The success of sunflower crop in Brazil is associated to the choice of adapted cultivars to different environments. When there are different genotypes answers in different environments, the release of new cultivars can be facilitated by carrying out studies of adaptability and stability of these genotypes to reduce the effects of genotypes x environments interaction. In Brazil, this information become more important, therefore the main cultivars had been developed in others countries, with different soil traits and climate. The objective of this study was to select sunflower genotypes for the sub-tropical region of Brazil. Experimental data from 1999/2000 to 2003/2004 were obtained by the National Sunflower Trials, coordinated by Embrapa Soja. The evaluated traits were grain and oil yields (kg ha-1). It was carried out a study of adaptability and stability of genotypes according to the methods proposed by PORTO et al. (2007), EBERHART & RUSSELL (1966) and ROCHA et al. (2005). Differently from the method of EBERHART & RUSSELL (1966), PORTO et al. (2007) selected genotypes, that despite of its lower overall average in relation to reference standard had good performance in specific environments. This method was more rigorous to select genotypes, when compared with ROCHA et al. (2005). For grain yield, genotype ACA 884 was indicated for general environments, EM 677008, Agrobel 930 and GV 26048 were indicated for favorable environments and ACA 885 for the unfavorable environments. In the same way, for oil yield, ACA 884 had general indication, GV 26048, CF 17, Agrobel 972 and Helio 358 are indicated for favorable environments and HT 01 and ACA 885 for the unfavorable ones.

Embora haja uma grande área para o cultivo de girassol no Brasil Central, poucas cultivares adaptadas encontram-se disponíveis no mercado. Esse trabalho teve o objetivo de selecionar cultivares de girassol para essa região de produção de grãos. Os dados foram obtidos da Rede Nacional de Ensaios de Avaliação de Cultivares de Girassol, coordenada pela Embrapa Soja, entre os anos de 2000 e 2004. Os caracteres avaliados foram rendimentos de grão e de óleo. Para a seleção das cultivares, dois critérios foram utilizados: i) a média geral obtida nos diferentes ambientes de teste; ii) a decomposição da média geral em ambientes favoráveis e desfavoráveis. A análise da decomposição da média geral possibilitou detectar para qual tipo de ambiente específico um genótipo poderia ser indicado. Para rendimento de grãos, o genótipo Helio 251 apresentou indicação geral; Milênio e CF 17 foram indicados para os ambientes favoráveis e, para os desfavoráveis, ACA 884, ACA 885 e ACA 872. Para rendimento de óleo, CF 13, Milênio, DK 4030, Helio 250 e ACA 872 tiveram indicação geral; enquanto que AG 966, GH 12, GV 26043, CF 17 e VDH 93 foram indicados para ambientes favoráveis, e VDH 488, Helio 251, ACA 884 e ACA 885 para os desfavoráveis. Em 2002, não foi realizada a decomposição da média geral. Nesse ano, Exp 37, AG 962, GV 26048 e AG 967 destacaram-se para rendimento de grãos e AG 962, AG 967, GV 26048, AG 972, BRS 191, Guarani, para rendimento de óleo.

Despite a large availability of areas suitable for sunflower cropping in Central Brazil, few adapted cultivars are available in the market. The objective of this work was to select sunflower cultivars adapted to this important production region. Experimental data from 2000 to 2004 were obtained by the National Sunflower Trials, coordinated by Embrapa Soja. The evaluated traits were grain and oil yields. Two criteria were used for selection of cultivars: i) the general mean obtained from different environments; ii) partitioning of general mean in favorable and unfavorable environments. Partitioning of the general mean allowed to detect the specific environment indicated for each cultivar. For grain yield, the cultivar Helio 251 presented general indication, Milênio and CF 17 could be indicated for favorable environments and ACA 884, ACA 885 and ACA 872 for the unfavorable ones. For oil yield, CF 13, Milênio, DK 4030, Helio 250 and ACA 872 had general indication; AG 966, GH 12, GV 26043, CF 17 and VDH 93 could be indicated for favorable environments, while VDH 488, Helio 251, ACA 884 and ACA 885 for the unfavorable conditions. In 2002, the partition of the general mean was not carried out. In this year, general mean of cultivars Exp 37, AG 962, GV 26048 and AG 967 were overweight the controls for grain yield and the cultivars AG 962, AG 967, GV 26048, AG 972, BRS 191, Guarani were overweight the controls for oil yield.

O objetivo deste trabalho foi comparar critérios para seleção de genótipos de girassol com base na média geral obtida em vários locais e sua decomposição em ambientes favoráveis e desfavoráveis e por meio de outros métodos de análise de adaptabilidade e estabilidade, como os de Eberhart & Russell, Lin & Binns, Carneiro e Carvalho et al. Foram analisados dados obtidos entre os anos de 1999 e 2004 na Rede Nacional de Ensaios de Girassol, coordenada pela Embrapa Soja e que conta com a participação de empresas públicas e privadas. Os caracteres avaliados foram rendimento de grãos e de óleo (kg ha-1). A análise da decomposição da média geral em médias de ambientes favoráveis e desfavoráveis (método da indicação com base na decomposição da média geral - IDMG) foi o critério mais adequado para a indicação de genótipos. A análise de regressão contribuiu com informações adicionais, indicando a responsividade e previsibilidade dos genótipos diante das mudanças ambientais.

The objective of this work was to compare criteria for selection of sunflower genotypes based on general mean obtained in different locations and its decomposition in favorable and unfavorable environments, as well as other methods of adaptability and stability, such as Eberhart & Russell, Lin & Binns, Carneiro and Carvalho et al. Data from 1999 to 2004 of the Official Sunflower Trials Network, coordinated by Embrapa Soja, were analyzed. The characters evaluated were yield of grains and oil (kg ha-1). The analysis of the decomposition of the general mean in favorable and unfavorable environment means (Indication Method - Partitioning of General Mean) was the most suitable for the indication of genotypes. However, the regression analysis contributed with additional information, indicating responsivity and previsibility of the genotypes to environmental changes.

RESUMO A etnobotânica vem sendo definida como o estudo das sociedades humanas em suas relações com as plantas. É uma disciplina antiga em sua prática, mas jovem em sua teoria. A pesquisa etnobotânica cresceu na última década, especialmente na América Latina. Esse crescimento exigiu o entendimento da disciplina na sua diversidade teórico-metodológica, conseqüência do seu caráter interdisciplinar e necessidade da sistematização da mesma. Este trabalho buscou resgatar e avaliar o ensino formal da etnobotânica em instituições brasileiras, a partir de questionários enviados a Instituições de ensino e pesquisa no país. Utilizou-se ainda a via eletrônica para atualizações referentes aos cursos de graduações. Foram encontradas 13 instituições que oferecem etnobotânica como disciplina específica, e 27 instituições, em que a etnobotânica não é oferecida formalmente, sendo abordada apenas como tópico, principalmente relacionada aos cursos da área de Ciências Biológicas. Tanto os cursos com disciplinas específicas quanto aqueles em que consta como tópico, concentram-se nas instituições das Regiões Sudeste (51%)e Nordeste (31%). O trabalho incluiu também uma avaliação dos conteúdos programáticos das disciplinas e bibliografias utilizadas. Os dados mostraram uma tendência de crescimento do ensino formal da etnobotânica tanto na graduação quanto na pós-graduação no Brasil.

ABSTRACT Ethnobotany is the study of human societies and their relationship with plants. It is an old discipline in practice, but young in theory. Ethnobotanical research has grown perceptibly in the past decade in many parts of the world, especially in Latin America. This growth calls for a broader understanding of the discipline in all its theoretical and methodological diversity. The interdisciplinary nature of ethnobotany also requires a greater academic systematization. This study focuses on the assessment of formal teaching methods of ethnobotany in Brazilian universities. Data were gathered from questionnaires sentover the Internet and filled out by graduate-course coordinators in Brazil, and by members of the Brazilian Ethnobotanical Committee of the Botanical Society of Brazil, and of the Brazilian Society of Ethnobiology and Ethnoecology. Thirteen Brazilian universities offer Ethnobotany as a specific discipline and in 27 other institutions, Ethnobotany is included as a topic in other disciplines. In both cases, these courses are generally offered by universities in Northeastern and Southeastern Brazil. The study included an evaluation of the contents as well as of references used in the courses. The data showed a strong tendency for growth of formal teaching of Ethnobotany in Brasil at both the undergraduate and graduate levels.

The article explores the role played by social vulnerability in the fact that there is a greater propensity for adolescent pregnancies in certain social contexts. A set of life histories of young women living in diverse socio-cultural contexts is used to illustrate the argument. It is shown how certain elements like permanence in school, access to information and sexual education, opportunities and life aspirations, and the existence of social and family support networks for young women can be influencing the frequency of adolescent pregnancies. Social vulnerability is defined as the set of these elements, and it is proposed that the hypothesis of the relationship between social vulnerability and adolescent pregnancy is tested, based on the results obtained in this study and from existing socio-demographic and health surveys.

El artículo explora el papel que juega la vulnerabilidad social en el hecho de que haya una mayor propensión a que ocurran embarazos en la adolescencia en ciertos contextos. Para ilustrarlo se analiza un conjunto de historias de vida de jóvenes pertenecientes a diversos contextos socioculturales. Se muestra cómo ciertos elementos como la permanencia en la escuela, el acceso a la información y educación sexual, las oportunidades y aspiraciones de vida y la existencia de redes familiares y sociales de apoyo de las jóvenes, pueden influir en la frecuencia de los embarazos durante la adolescencia. Se denomina vulnerabilidad social al conjunto de dichos elementos y se propone hacer análisis cuantitativos ulteriores, con base en las encuestas sociodemográficas y de salud con las que se cuenta para poner a prueba la hipótesis de la relación entre vulnerabilidad social y embarazo adolescente.

OBJECTIVE: To understand how the social construction and expression of masculinity among male adolescents and young adults are related to sexual health and reproductive risks. MATERIAL AND METHODS: The study was carried out in an underserved and a popular area of Mexico City. Eighteen focal groups and 18 individual interviews were applied to a sample of males from three age groups: 10 to 14, 15 to 19, and 20 to 24 years. Data analysis was performed inductively through open codification of the verbal transcriptions. These were used to create more abstract concepts and search for relationships among them. RESULTS: This paper centers on interpretations of masculinity as expressed by the youngsters themselves. Our research sheds light on what youngsters do and say to "be men". Their ideas and practices produce different forms of masculinity through which risk behavior is manifested, as well as specific speech and dressing styles, and ways of courting and "going steady". These behaviors and their meanings are associated with sexual and reproductive health risk taking. CONCLUSIONS: The traditional model of masculinity characteristic of both social settings involves poor communication about sexuality in couple relationships, which results in infrequent protection and exposure to Sexually Transmitted Infections and unwanted pregnancies. On the other hand, their economic living conditions prevent them from fully practicing central elements of their own concept of masculinity, such as being a hard worker, a provider, and a responsible person. These unmet needs may cause frustration, aggression, and domestic violence.

OBJETIVO: Comprender cómo la construcción social y la expresión de la masculinidad entre los adolescentes y varones jóvenes se articulan con los riesgos para la salud sexual y reproductiva. MATERIAL Y MÉTODOS: El estudio se realizó en una zona "marginal" y otra "popular" de la Ciudad de México. Se llevaron a cabo 18 grupos focales y 18 entrevistas individuales a una muestra propositiva de varones de tres grupos de edad: 10 a 14, 15 a 19 y 20 a 24. El análisis de la información se hizo de forma inductiva, mediante una codificación abierta de las transcripciones verbales, a partir de la cual se generaron conceptos más abstractos y se buscaron las relaciones entre ellos. RESULTADOS: Este trabajo se enfoca en las maneras de entender la masculinidad, tal y como fueron expresadas por los jóvenes. Nuestra investigación arroja alguna luz sobre lo que los adolescentes dicen y hacen para "ser hombres". Sus ideas y prácticas llevan a varias formas de masculinidad mediante las cuales se reconstruyen comportamientos arriesgados, estilos de hablar y de vestir, formas de cortejo y de noviazgo específicas. Estos y sus significados son articulados con los riesgos en el campo de la salud sexual y reproductiva de los jóvenes y de sus parejas. CONCLUSIONES: El modelo tradicional de masculinidad que predomina en ambos sectores sociales tiene como resultado, por una parte, que haya poca comunicación sobre la sexualidad en las relaciones de pareja y que, consecuentemente, la utilización de medidas de protección se dé en muy raras ocasiones, exponiendo a los jóvenes a ITS y al riesgo de transformarse en padres sin ser aún adultos. Por otra parte, las condiciones económicas en que viven dificultan que lleven a la práctica elementos centrales de su propio concepto de masculinidad, como el ser trabajador, proveedor, responsable, lo que pudiera traducirse en frustración, agresividad y en violencia intrafamiliar.

OBJECTIVE: To understand how the social construction and expression of masculinity among male adolescents and young adults are related to sexual health and reproductive risks. MATERIAL AND METHODS: The study was carried out in an underserved and a popular area of Mexico City. Eighteen focal groups and 18 individual interviews were applied to a sample of males from three age groups: 10 to 14, 15 to 19, and 20 to 24 years. Data analysis was performed inductively through open codification of the verbal transcriptions. These were used to create more abstract concepts and search for relationships among them. RESULTS: This paper centers on interpretations of masculinity as expressed by the youngsters themselves. Our research sheds light on what youngsters do and say to "be men". Their ideas and practices produce different forms of masculinity through which risk behavior is manifested, as well as specific speech and dressing styles, and ways of courting and "going steady". These behaviors and their meanings are associated with sexual and reproductive health risk taking. CONCLUSIONS: The traditional model of masculinity characteristic of both social settings involves poor communication about sexuality in couple relationships, which results in infrequent protection and exposure to Sexually Transmitted Infections and unwanted pregnancies. On the other hand, their economic living conditions prevent them from fully practicing central elements of their own concept of masculinity, such as being a hard worker, a provider, and a responsible person. These unmet needs may cause frustration, aggression, and domestic violence.

OBJETIVO: Comprender cómo la construcción social y la expresión de la masculinidad entre los adolescentes y varones jóvenes se articulan con los riesgos para la salud sexual y reproductiva. MATERIAL Y MÉTODOS: El estudio se realizó en una zona "marginal" y otra "popular" de la Ciudad de México. Se llevaron a cabo 18 grupos focales y 18 entrevistas individuales a una muestra propositiva de varones de tres grupos de edad: 10 a 14, 15 a 19 y 20 a 24. El análisis de la información se hizo de forma inductiva, mediante una codificación abierta de las transcripciones verbales, a partir de la cual se generaron conceptos más abstractos y se buscaron las relaciones entre ellos. RESULTADOS: Este trabajo se enfoca en las maneras de entender la masculinidad, tal y como fueron expresadas por los jóvenes. Nuestra investigación arroja alguna luz sobre lo que los adolescentes dicen y hacen para "ser hombres". Sus ideas y prácticas llevan a varias formas de masculinidad mediante las cuales se reconstruyen comportamientos arriesgados, estilos de hablar y de vestir, formas de cortejo y de noviazgo específicas. Estos y sus significados son articulados con los riesgos en el campo de la salud sexual y reproductiva de los jóvenes y de sus parejas. CONCLUSIONES: El modelo tradicional de masculinidad que predomina en ambos sectores sociales tiene como resultado, por una parte, que haya poca comunicación sobre la sexualidad en las relaciones de pareja y que, consecuentemente, la utilización de medidas de protección se dé en muy raras ocasiones, exponiendo a los jóvenes a ITS y al riesgo de transformarse en padres sin ser aún adultos. Por otra parte, las condiciones económicas en que viven dificultan que lleven a la práctica elementos centrales de su propio concepto de masculinidad, como el ser trabajador, proveedor, responsable, lo que pudiera traducirse en frustración, agresividad y en violencia intrafamiliar.

The present work is a review of the most commonly used arguments to define pregnancy during adolescence as a public problem: its supposed increase, contribution to accelerated population growth, adverse effects on maternal and child health and contribution to the persistence of poverty. Some elements are proposed for an alternative explanation with the intention of defining with more rigour and pertinence the real problems related to pregnancy during adolescence, thus allowing an improvement in the design of policies and programs to confront it.

Se hace una revisión de los argumentos comúnmente utilizados para definir al embarazo adolescente como un problema público: su supuesto incremento, su contribución al crecimiento acelerado de la población, sus efectos adversos sobre la salud de la madre y del niño y su contribución a la persistencia de la pobreza; y se proponen algunos elementos para una posible explicación alternativa, con la intención de contribuir a definir con mayor rigor y pertinencia los problemas reales vinculados con el embarazo en adolescentes y poder diseñar políticas y programas más adecuados para enfrentarlos.