Economia solidária e trabalho coletivo : Um olhar sobre a Cooperativa do Riachão no Norte de Minas Gerais - Brasil

It is intended to discuss the prospect of collective work in solidarity economy, from experiences with those of the Cooperative Riachao workers, located in a rural community in the municipality of Montes Claros, Minas Gerais / Brazil, this approximately 240 farming families extractive are benefited with the generation of jobs and income through initiatives grounded in associations, cooperatives and collectives. Among the 80 to 90 years, appeared inBrazil experiences of solidarity, resulting economy of the labor market crisis and rising unemployment, and an important response to the workers in relation to changes in the world of work. It is grounded in the organization of groups of workers, by way of solidarity, community, cooperation, and self-management reactions. In this sense, we intend to present the achievements, challenges and dilemmas of workers COOPERIACHAO, around a project that aims at empowerment of social actors and social transformation of the subject

Intervenciones críticas en la poesía última (Prácticas de articulación y agendas complementarias)

Indagaremos algunas dominantes en la intervención crítica sobre el género poético en lengua española de las últimas décadas, proponiendo alternativas diferentes a las convencionales operaciones de recorte y exclusión de grupos y tendencias, a los que nos tiene acostumbrada la crítica mayoritaria, desde antologías y suplementos literarios, preocupada por rotular, oponer y disgregar, diseñando mapas de polaridades irreconciliables y nombres propios consagrados como oráculos, sin nexo con sus coetáneos, asimilados como adversarios, y potenciando rivalidades personales, o comportamientos públicos de los actores por encima de sus escrituras. Para superar estas reductivas miradas se hace necesario ensayar propuestas de articulación: suturar fisuras imaginarias para integrar praxis materiales; imaginar políticas de intercambio textual e ideológico; admitir un trazado de zonas de confluencia permeables; asumir que los poetas vehiculizan identidades móviles y receptivas, a favor de un diálogo inter-local mutuamente enriquecedor.

(Table 1) Lithofacies interpretation and distribution in sediment core CRP-3

Seven hundred and nineteen samples from throughout the Cainozoic section in CRP-3 were analysed by a Malvern Mastersizes laser particle analyser, in order to derive a stratigraphic distribution of grain-size parameters downhole. Entropy analysis of these data (using the method of Woolfe & Michibayashi, 1995) allowed recognition of four groups of samples, each group characterised by a distinctive grain-size distribution. Group 1, which shows a multi-modal distribution, corresponds to mudrocks, interbedded mudrock/sandstone facies, muddy sandstones and diamictites. Group 2, with a sand-grade mode but showing wide dispersion of particle size, corresponds to muddy sandstones, a few cleaner sandstones and some conglomerates. Group 3 and Group 4 are also sand-dominated, with better grain-size sorting, and correspond to clean, well-washed sandstones of varying mean grain-size (medium and fine modes, respectively). The downhole disappearance of Group 1, and dominance of Groups 3 and 4 reflect a concomitant change from mudrock- and diamictite-rich lithology to a section dominated by clean, well-washed sandstones with minor conglomerates. Progressive downhole increases in percentage sand and principal mode also reflect these changes. Significant shifts in grain-size parameters and entropy group membership were noted across sequence boundaries and seismic reflectors, as recognised in other studies.

La Práctica del Desarrollo Local: Veinticinco Años de Experiencia del Instituto de Desarrollo Comunitario de Cuenca en Territorios Rurales

La investigación tiene como objetivo principal analizar la experiencia de la Asociación Instituto de Desarrollo Comunitario de Cuenca, en la práctica del desarrollo local en los territorios rurales de esta provincia. La necesidad de estimular a la población para que ésta forme parte de su propio desarrollo, pone de manifiesto la existencia de determinadas instituciones externas que a través de procesos como la facilitación, movilizan y crean capacidades en las personas y las empujan hacia la participación. Este es el caso del IDC de Cuenca que nace en 1985 como entidad privada —declarada de utilidad pública y sin ánimo de lucro—, con la voluntad de sus fundadores de trabajar en el desarrollo local de las zonas deprimidas de Cuenca. La labor desarrollada en estos más de 25 años tiene como centro la promoción de la persona como ser individual y como parte de su comunidad. Para la elaboración de la Tesis, se ha utilizado la metodología del caso de estudio centrado en el análisis de la experiencia del IDC respecto de las cuatro investigaciones realizadas centradas en el proceso de facilitación, las herramientas de formación e información, y la dinamización del tejido asociativo como resultado del proceso. La labor del IDC en la provincia de Cuenca se ha desarrollado a través de la ejecución de proyectos. Éstos se han llevado a cabo por medio de procesos de facilitación donde la creación de grupos de trabajo ha permitido mejorar la estructuración social de las zonas rurales. Los grupos de trabajo son creados y apoyados por el IDC a través de la utilización de las herramientas de información y formación, que deben estar adaptadas a las necesidades de los individuos y en este caso cuentan con una metodología de aplicación propia. La creación de diferentes entidades —asociaciones, cooperativas, clubes, etc.—, ha sido uno de los resultados del trabajo desarrollado por el IDC a través de los procesos de facilitación que han mejorado la estructuración de la sociedad rural. Pese a la complejidad tanto de los procesos de desarrollo como de la evaluación final de dichos procesos, la creación de grupos capaces de alcanzar determinados objetivos propuestos en su comunidad potenciando sus propios recursos, son el ejemplo de la dinamización social que se lleva produciendo en la provincia de Cuenca desde hace más de 25 años. The research's main objective is to analyze the experience of the Asociación Instituto de Desarrollo Comunitario de Cuenca, in the practice of local development in rural areas of this province. The need to encourage more people to take part of their own development, reveals the existence of certain external institutions which through processes such as facilitation, mobilize and create capacities in people to foster their participation. This is the case of the IDC of Cuenca that was born in 1985 as a private entity —declared of public utility and as non profit entity— with the intention, as stated by its founders, of working in the local development of the disadvantaged areas of Cuenca. The work carried out in these more than 25 years focused on promoting the person as an individual and as part of their community. In this research, the methodology of the case study has been used in the analysis of the experience of the IDC in four investigations carried out regarding the process of facilitation, training and information tools, and the improvement of social involvement as a result of the development process. The work of the IDC in the province of Cuenca has been developed through the implementation of projects. They have been carried out through processes of facilitation, where the creation of working groups has improved the social structuring of rural areas. The working groups are created and supported by the IDC through the use of tools of information and training, which must be adapted to the individual needs in each case, and even count with their own implementation methodology. The creation of different entities —associations, cooperatives, clubs, etc.— has been one of the results of the work carried out by the IDC through processes of facilitation which have improved the structure of rural society. Despite the complexity of development processes and the final assessment of these processes, the creation of groups able to reach certain objectives proposed in their community promoting its own resources, is an example of the social involvement that has been taking place in the province of Cuenca for more than 25 years.

Implementación de ingeniería virtual con Joomla!

El Proyecto Final de Carrera(PFC)Implementación de Ingeniería Virtual con Joomla! tiene como objetivo la creación de una plataforma web. Para desarrollar un proyecto de ingeniería multidisciplinar, basado en el trabajo en red, grupos de trabajo y el trabajo flexible. El trabajo en red es desempeñar el trabajo por medio de las Tecnología de la Información y la comunicación (TIC). Los grupos de trabajo están compuestos por personas multidisciplinares, multirraciales, de diferentes religiones, situados en husos horarios distintos y multiculturales donde la colaboración, flexibilidad y la compartición de recursos están a la orden del día. La flexible es la capacidad de adaptación de los propios trabajadores a la demanda de la productividad, los responsables depositan sobre ellos su confianza, recibiendo el trabajo terminado en forma y fecha. Estos trabajadores no necesitan una supervisión constante ni un sitio fijo donde realizar su trabajo. Todo lo que necesitan esta en la red, la información que necesitan como las herramientas. Convirtiéndose este tipo de trabajador en teletrabajadores. Estos trabajadores utilizan de forma intensiva sus conocimientos, no se puede permitir quedarse obsoletos en su conocimientos, sería su gran desgracia. Por está razón, necesitan estar formándose continuamente, aprendiendo y conociendo las nuevas tecnologías que aparecen. Con el objetivo de conseguir nuevas líneas de negocio, con el fin de lograr nuevos ingresos. Los trabajadores que hacen un uso intensivo en la tecnología de la información y comunicación, se caracterizan por la continua innovación y cambio tecnológico. Estos trabajadores necesitan una red profesional, social amplia con enlaces fuertes y poderosos. Las redes son importantes, para estar actualizado con las innovaciones que se realizan en las empresas, optar a nuevos puesto de trabajo, curso en nuevas tecnologías… Gracias a los servicios actuales en Internet facilitan mantener vivos una gran cantidad de enlaces (contactos), en comparación con otras épocas. La plataforma propuesta en este proyecto final de carrera esta compuesta de todas las herramientas necesarias para que estos trabajadores puedan desarrollar su actividad y mantenimiento de sus redes profesionales. Abstract: The aim of this Final Project of Career, Implementation of Virtual Engineering with Joomla!, is to create a web software application where a multidisciplinary engineering project bases on the networking, working groups and the flexible working can be implemented. The networking is the job through the Information Technology and Communication (ITC) where working groups compounded of multidisciplinary and multiracial professions, different religions and located in different time zones are created. The multicultural environment, collaboration, flexibility and to share resources are the order of the day on this kind of groups. The flexibility is the ability to adaptability of workers to the productivity demand, with the trust which is placed on them by supervisor people who wait to receive the work completed in a specific form and date. These workers do not need either constant supervision or a fixed site where to do the job. Everything the workers need is on the network, as the information as the tools, that is why they become teleworkers. These workers demand a high use of their knowledge, so it can not be allowed to become obsolete. This would be a great misfortune. That is why they need to continue learning and knowing the new technologies emerging with the aim of getting new revenues. Workers do an intensive use of the information technology and communication, characterized by continuous innovation and technological change. These workers need a broad social and professional network with great power. This network is important to keep updated with innovations taking place at the companies, to apply for a new job, a new technology course etc.. Thanks to Internet services a bigger number of contacts are provided compared to earlier times. The software application of this project is compounded with enough tools with the aim of the workers can carry out their activity and maintenance of the links on their professional nets.

Un modelo de encaminamiento en las redes móviles ad hoc con QoS

En la última década ha aumentado en gran medida el interés por las redes móviles Ad Hoc. La naturaleza dinámica y sin infraestructura de estas redes, exige un nuevo conjunto de algoritmos y estrategias para proporcionar un servicio de comunicación fiable extremo a extremo. En el contexto de las redes móviles Ad Hoc, el encaminamiento surge como una de las áreas más interesantes para transmitir información desde una fuente hasta un destino, con la calidad de servicio de extremo a extremo. Debido a las restricciones inherentes a las redes móviles, los modelos de encaminamiento tradicionales sobre los que se fundamentan las redes fijas, no son aplicables a las redes móviles Ad Hoc. Como resultado, el encaminamiento en redes móviles Ad Hoc ha gozado de una gran atención durante los últimos años. Esto ha llevado al acrecentamiento de numerosos protocolos de encaminamiento, tratando de cubrir con cada uno de ellos las necesidades de los diferentes tipos de escenarios. En consecuencia, se hace imprescindible estudiar el comportamiento de estos protocolos bajo configuraciones de red variadas, con el fin de ofrecer un mejor encaminamiento respecto a los existentes. El presente trabajo de investigación muestra precisamente una solución de encaminamiento en las redes móviles Ad Hoc. Dicha solución se basa en el mejoramiento de un algoritmo de agrupamiento y la creación de un modelo de encaminamiento; es decir, un modelo que involucra la optimización de un protocolo de enrutamiento apoyado de un mecanismo de agrupación. El algoritmo mejorado, denominado GMWCA (Group Management Weighted Clustering Algorithm) y basado en el WCA (Weighted Clustering Algorithm), permite calcular el mejor número y tamaño de grupos en la red. Con esta mejora se evitan constantes reagrupaciones y que los jefes de clústeres tengan más tiempo de vida intra-clúster y por ende una estabilidad en la comunicación inter-clúster. En la tesis se detallan las ventajas de nuestro algoritmo en relación a otras propuestas bajo WCA. El protocolo de enrutamiento Ad Hoc propuesto, denominado QoS Group Cluster Based Routing Protocol (QoSG-CBRP), utiliza como estrategia el empleo de clúster y jerarquías apoyada en el algoritmo de agrupamiento. Cada clúster tiene un jefe de clúster (JC), quien administra la información de enrutamiento y la envía al destino cuando esta fuera de su área de cobertura. Para evitar que haya constantes reagrupamientos y llamados al algoritmo de agrupamiento se consideró agregarle un jefe de cluster de soporte (JCS), el que asume las funciones del JC, siempre y cuando este haya roto el enlace con los otros nodos comunes del clúster por razones de alejamiento o por desgaste de batería. Matemáticamente y a nivel de algoritmo se han demostrado las mejoras del modelo propuesto, el cual ha involucrado el mejoramiento a nivel de algoritmo de clustering y del protocolo de enrutamiento. El protocolo QoSG-CBRP, se ha implementado en la herramienta de simulación Network Simulator 2 (NS2), con la finalidad de ser comparado con el protocolo de enrutamiento jerárquico Cluster Based Routing Protocol (CBRP) y con un protocolo de enrutamiento Ad Hoc reactivo denominado Ad Hoc On Demand Distance Vector Routing (AODV). Estos protocolos fueron elegidos por ser los que mejor comportamiento presentaron dentro de sus categorías. Además de ofrecer un panorama general de los actuales protocolos de encaminamiento en redes Ad Hoc, este proyecto presenta un procedimiento integral para el análisis de capacidades de la propuesta del nuevo protocolo con respecto a otros, sobre redes que tienen un alto número de nodos. Estas prestaciones se miden en base al concepto de eficiencia de encaminamiento bajo parámetros de calidad de servicio (QoS), permitiendo establecer el camino más corto posible entre un nodo origen y un nodo destino. Con ese fin se han realizado simulaciones con diversos escenarios para responder a los objetivos de la tesis. La conclusiones derivadas del análisis de los resultados permiten evaluar cualitativamente las capacidades que presenta el protocolo dentro del modelo propuesto, al mismo tiempo que avizora un atractivo panorama en líneas futuras de investigación. ABSTRACT In the past decade, the interest in mobile Ad Hoc networks has greatly increased. The dynamic nature of these networks without infrastructure requires a new set of algorithms and strategies to provide a reliable end-to-end communication service. In the context of mobile Ad Hoc networks, routing emerges as one of the most interesting areas for transmitting information from a source to a destination, with the quality of service from end-to-end. Due to the constraints of mobile networks, traditional routing models that are based on fixed networks are not applicable to Ad Hoc mobile networks. As a result, the routing in mobile Ad Hoc networks has experienced great attention in recent years. This has led to the enhancement of many routing protocols, trying to cover with each one of them, the needs of different types of scenarios. Consequently, it is essential to study the behavior of these protocols under various network configurations, in order to provide a better routing scheme. Precisely, the present research shows a routing solution in mobile Ad Hoc networks. This solution is based on the improvement of a clustering algorithm, and the creation of a routing model, ie a model that involves optimizing a routing protocol with the support of a grouping mechanism. The improved algorithm called GMWCA (Group Management Weighted Clustering Algorithm) and based on the WCA (Weighted Clustering Algorithm), allows to calculate the best number and size of groups in the network. With this enhancement, constant regroupings are prevented and cluster heads are living longer intra-cluster lives and therefore stability in inter-cluster communication. The thesis details the advantages of our algorithm in relation to other proposals under WCA. The Ad Hoc routing protocol proposed, called QoS Group Cluster Based Routing Protocol (QoSG-CBRP), uses a cluster-employment strategy and hierarchies supported by the clustering algorithm. Each cluster has a cluster head (JC), who manages the routing information and sends it to the destination when is out of your coverage area. To avoid constant rearrangements and clustering algorithm calls, adding a support cluster head (JCS) was considered. The JCS assumes the role of the JC as long as JC has broken the link with the other nodes in the cluster for common restraining reasons or battery wear. Mathematically and at an algorithm level, the improvements of the proposed model have been showed, this has involved the improvement level clustering algorithm and the routing protocol. QoSG-CBRP protocol has been implemented in the simulation tool Network Simulator 2 (NS2), in order to be compared with the hierarchical routing protocol Cluster Based Routing Protocol (CBRP) and with the reactive routing protocol Ad Hoc On Demand Distance Vector Routing (AODV). These protocols were chosen because they showed the best individual performance in their categories. In addition to providing an overview of existing routing protocols in Ad Hoc networks, this project presents a comprehensive procedure for capacity analysis of the proposed new protocol with respect to others on networks that have a high number of nodes. These benefits are measured based on the concept of routing efficiency under the quality of service (QoS) parameters, thus allowing for the shortest possible path between a source node and a destination node. To meet the objectives of the thesis, simulations have been performed with different scenarios. The conclusions derived from the analysis of the results to assess qualitatively the protocol capabilities presented in the proposed model, while an attractive scenario for future research appears.

Empowerment Evaluation in Spain: The Critical Friend Role in Working with Rural Communities

Rural communities in Cuenca (Spain) are characterized by a great social dislocation, mostly due to the low population density in these areas. In this way, the existence of groups of citizens able to be active agents of their development process is a critical aspect for any community-based development process in this Spanish region. The Institute of Community Development of Cuenca (IDC) has been working with this type of groups for the last 30 years focusing on the organizational empowerment of the rural communities. Main tools in this process have been the empowerment evaluation approach and the critical friend role when helping the groups to achieve their objectives and reinforcing them. This chapter analyses the empowerment process and how the critical friend role is nourished by the facilitator figure.

Qual o papel da pedagogia diferenciada no desenvolvimento de aprendizagens significativas em crianças do contexto pré - escolar?

Relatório de estágio apresentado para a obtenção do grau de mestre na especialidade profissional de Educação pré -escolar

NEOTRIBALISMO E NOVOS MOVIMENTOS RELIGIOSOS: ESTUDO DE CASO DA PRÁXIS DA IGREJA BOLA DE NEVE CHURCH

A presente pesquisa Neotribalismo e Novos Movimentos Religiosos:Estudo de Caso das Práxis da Igreja Bola de Neve Church é uma investigação in loco que se propõe analisar, descrever e interpretar o contexto de uma práxis religiosa emergente, com uma abordagem teórico-científica deste movimento religioso. A partir da década de 80 do século XX houve uma nova configuração social permitindo criar grupos de identificação própria, principalmente no contexto urbano. Um destes grupos que vieram a surgir foram as chamadas tribos urbanas. Esta nova configuração neo-tribalista permitiu o desenvolvimento de expressões de religiosidade própria, chamado de Novos Movimentos Religiosos, dentre os quais, destaca-se a Igreja Bola de Neve Church. O tema desta pesquisa científica tem despertado grande interesse pelos cientistas sociais e da religião, apresentando-se, também, como um novo desafio aos pastoralistas por analisar os efeitos que este fenômeno religioso implica na sociedade contemporânea. Por isso, além de compreender os fundamentos teórico-científicos da construção do modelo social neotribalista e dos Novos Movimentos Religiosos, a pesquisa propõe-se a investigar o surgimento, descrevê-lo e interpretar suas práticas religiosas sob a chave hermenêutica da teoria da práxis religiosa, a fim de compreender como a Igreja Bola de Neve Church é interpretada pelas religiões de tradição cristã.(AU)

NEOTRIBALISMO E NOVOS MOVIMENTOS RELIGIOSOS: ESTUDO DE CASO DA PRÁXIS DA IGREJA BOLA DE NEVE CHURCH

A presente pesquisa Neotribalismo e Novos Movimentos Religiosos:Estudo de Caso das Práxis da Igreja Bola de Neve Church é uma investigação in loco que se propõe analisar, descrever e interpretar o contexto de uma práxis religiosa emergente, com uma abordagem teórico-científica deste movimento religioso. A partir da década de 80 do século XX houve uma nova configuração social permitindo criar grupos de identificação própria, principalmente no contexto urbano. Um destes grupos que vieram a surgir foram as chamadas tribos urbanas. Esta nova configuração neo-tribalista permitiu o desenvolvimento de expressões de religiosidade própria, chamado de Novos Movimentos Religiosos, dentre os quais, destaca-se a Igreja Bola de Neve Church. O tema desta pesquisa científica tem despertado grande interesse pelos cientistas sociais e da religião, apresentando-se, também, como um novo desafio aos pastoralistas por analisar os efeitos que este fenômeno religioso implica na sociedade contemporânea. Por isso, além de compreender os fundamentos teórico-científicos da construção do modelo social neotribalista e dos Novos Movimentos Religiosos, a pesquisa propõe-se a investigar o surgimento, descrevê-lo e interpretar suas práticas religiosas sob a chave hermenêutica da teoria da práxis religiosa, a fim de compreender como a Igreja Bola de Neve Church é interpretada pelas religiões de tradição cristã.(AU)

RELIGIÃO, CORPO E EMOÇÃO: EDUCAÇÃO DOS SENTIDOS E HABITUS DE CLASSE NA IGREJA COMUNIDADE DA GRAÇA NO ABC PAULISTA

O objeto de estudo desta pesquisa é a Comunidade da Graça, presente há dez anos em São Bernardo do Campo, região do ABC paulista. Analisa-se o lugar da emoção religiosa e sua relação com a educação dos sentidos nesta confraria protestante pentecostal formada majoritariamente por pessoas de classe média, como propiciadora da assimilação de um habitus e de um forte auto-controle individual evidenciando a eficácia do adestramento corporal pela via da religião. Imersa em uma realidade social de muitas mudanças que provocam reconfigurações das religiões, no tipo específico de pentecostalismo estudado nota-se que, na gestão dos bens simbólicos, o ingrediente emocional é o principal acessório a fim de responder às demandas coletivas e individuais deste público religioso. Se há alguns anos a centralidade cúltica do protestantismo pentecostal estava no ouvir a prédica e reviver a experiência do pentecostes cristão, hoje em dia o foco neste é a emoção que deve perpassar todo o culto. O mesmo ocorre nos dois espaços catequéticos privilegiados desta igreja, a saber, a reunião no templo chamada de Conhecendo as Escrituras e os encontros de grupos nos lares. Esta mudança se evidencia, também, nos corpos dos fiéis, pois estes se constróem e modelam-se à realidade social vigente e expressam as experiências vivenciadas neste contexto. A partir da observação dos cultos e reuniões catequéticas desta igreja, analisa-se neste trabalho o modo como a emoção religiosa é construída, difundida e reproduzida, levando-se em consideração as condições sociais e econômicas específicas do grupo religioso em questão.(AU)

RELIGIÃO, CORPO E EMOÇÃO: EDUCAÇÃO DOS SENTIDOS E HABITUS DE CLASSE NA IGREJA COMUNIDADE DA GRAÇA NO ABC PAULISTA

O objeto de estudo desta pesquisa é a Comunidade da Graça, presente há dez anos em São Bernardo do Campo, região do ABC paulista. Analisa-se o lugar da emoção religiosa e sua relação com a educação dos sentidos nesta confraria protestante pentecostal formada majoritariamente por pessoas de classe média, como propiciadora da assimilação de um habitus e de um forte auto-controle individual evidenciando a eficácia do adestramento corporal pela via da religião. Imersa em uma realidade social de muitas mudanças que provocam reconfigurações das religiões, no tipo específico de pentecostalismo estudado nota-se que, na gestão dos bens simbólicos, o ingrediente emocional é o principal acessório a fim de responder às demandas coletivas e individuais deste público religioso. Se há alguns anos a centralidade cúltica do protestantismo pentecostal estava no ouvir a prédica e reviver a experiência do pentecostes cristão, hoje em dia o foco neste é a emoção que deve perpassar todo o culto. O mesmo ocorre nos dois espaços catequéticos privilegiados desta igreja, a saber, a reunião no templo chamada de Conhecendo as Escrituras e os encontros de grupos nos lares. Esta mudança se evidencia, também, nos corpos dos fiéis, pois estes se constróem e modelam-se à realidade social vigente e expressam as experiências vivenciadas neste contexto. A partir da observação dos cultos e reuniões catequéticas desta igreja, analisa-se neste trabalho o modo como a emoção religiosa é construída, difundida e reproduzida, levando-se em consideração as condições sociais e econômicas específicas do grupo religioso em questão.(AU)

Australian lungfish neurohypophysial hormone genes encode vasotocin and [Phe2]mesotocin precursors homologous to tetrapod-type precursors

In view of the well-established role of neurohypophysial hormones in osmoregulation of terrestrial vertebrates, lungfishes are a key group for study of the molecular and functional evolution of the hypothalamo-neurohypophysial system. Here we report on the primary structure of the precursors encoding vasotocin (VT) and [Phe2]mesotocin ([Phe2]MT) of the Australian lungfish, Neoceratodus forsteri. Genomic sequence analysis and Northern blot analysis confirmed that [Phe2]MT is a native oxytocin family peptide in the Australian lungfish, although it has been reported that the lungfish neurohypophysis contains MT. The VT precursor consists of a signal peptide, VT, that is connected to a neurophysin by a Gly-Lys-Arg sequence, and a copeptin moiety that includes a Leu-rich core segment and a glycosylation site. In contrast, the [Phe2]MT precursor does not contain a copeptin moiety. These structural features of the lungfish precursors are consistent with those in tetrapods, but different from those in teleosts where both VT and isotocin precursors contain a copeptin-like moiety without a glycosylation site at the carboxyl terminals of their neurophysins. Comparison of the exon/intron organization also supports homology of the lungfish [Phe2]MT gene with tetrapod oxytocin/MT genes, rather than with teleost isotocin genes. Moreover, molecular phylogenetic analysis shows that neurohypophysial hormone genes of the lungfish are closely related to those of the toad. The present results along with previous morphological findings indicate that the hypothalamo-neurohypophysial system of the lungfish has evolved along the tetrapod lineage, whereas the teleosts form a separate lineage, both within the class Osteichthyes.

A Ubiquitin-Conjugating Enzyme Is Essential for Developmental Transitions in Dictyostelium

We have identified a developmentally essential gene, UbcB, by insertional mutagenesis. The encoded protein (UBC1) shows very high amino acid sequence identity to ubiquitin-conjugating enzymes from other organisms, suggesting that UBC1 is involved in protein ubiquitination and possibly degradation during Dictyostelium development. Consistent with the homology of the UBC1 protein to UBCs, the developmental pattern of protein ubiquitination is altered in ubcB-null cells. ubcB-null cells are blocked in the ability to properly execute the developmental transition that occurs between the induction of postaggregative gene expression during mound formation and the induction of cell-type differentiation and subsequent morphogenesis. ubcB-null cells plated on agar form mounds with normal kinetics; however, they remain at this stage for ∼10 h before forming multiple tips and fingers that then arrest. Under other conditions, some of the fingers form migrating slugs, but no culmination is observed. In ubcB-null cells, postaggregative gene transcripts accumulate to very high levels and do not decrease significantly with time as they do in wild-type cells. Expression of cell-type-specific genes is very delayed, with the level of prespore-specific gene expression being significantly reduced compared with that in wild-type cells. lacZ reporter studies using developmentally regulated and cell-type-specific promoters suggest that ubcB-null cells show an unusually elevated level of staining of lacZ reporters expressed in anterior-like cells, a regulatory cell population found scattered throughout the aggregate, and reduced staining of a prespore reporter. ubcB-null cells in a chimeric organism containing predominantly wild-type cells are able to undergo terminal differentiation but show altered spatial localization. In contrast, in chimeras containing only a small fraction of wild-type cells, the mature fruiting body is very small and composed almost exclusively of wild-type cells, with the ubcB-null cells being present as a mass of cells located in extreme posterior of the developing organism. The amino acid sequence analysis of the UbcB open reading frame (ORF) and the analysis of the developmental phenotypes suggest that tip formation and subsequent development requires specific protein ubiquitination, and possibly degradation.

Arthropods: Developmental diversity within a (super) phylum

The expression patterns of developmental genes provide new markers that address the homology of body parts and provide clues as to how body plans have evolved. Such markers support the idea that insect wings evolved from limbs but refute the idea that insect and crustacean jaws are fundamentally different in structure. They also confirm that arthropod tagmosis reflects underlying patterns of Hox gene regulation but they do not yet resolve to what extent Hox expression domains may serve to define segment homologies.