Protein-protein interactions of the DNA polymerase ð complex in the fission yeast Schizosaccharomyces pombe

In eukaryotes there are three essential DNA polymerases that are involved in the bulk o f DNA replication: pola, polS and pole. P ola is involved in generating a short RNA-DNA primer. PolS and 8 are involved in the elongation process o f DNA replication. It has been suggested that polS is the key enzyme that performs all o f the processive DNA replication since the catalytic domains o f pole are not essential.In S. pombe polδ is comprised of four subunits: Pol3- the catalytic or A subunit, Cdcl- the B subunit, Cdc27- the C subunit, and Cdml- the D subunit. Polδ in S. cerevisiae and mammals have homologues o f these subunits, except for the D subunit of which there is no homologue in S. cerevisiae.In this thesis polS from S. pombe has been studied in two ways. One approach was to investigate the protein-protein interactions within polδ, and the other was to investigate Cdcl, the highly conserved B subunit of unknown function. The proteinprotein interactions were investigated using a combination of two-hybrid assays and mutational analysis. Cdcl was investigated by performing extensive mutational analysis using both random and site directed methods.The combination of approaches has demonstrated that the C- terminal ZnF2 region of both S. pom be and S. cerevisiae A subunit (Pol3) is involved in the direct binding to the B subunit. The four cysteines present in the zinc finger are involved in maintaining the structure of both S. pombe and S. cerevisiae ZnF2. Mutational analysis o f Cdcl (the S. pombe B subunit) has identified a conserved region (DomIII) that could be involved in the function of Cdcl. Additionally, binding assays with the Cdcl mutants have suggested a region of Cdcl (from amino acids 293 to 329) as being involved in the binding to Pol3

Geometrical Structures of Space-Time in General Relativity

Space-Time in general relativity is a dynamical entity because it is subject to the Einstein field equations. The space-time metric provides different geometrical structures: conformal, volume, projective and linear connection. A deep understanding of them has consequences on the dynamical role played by geometry. We present a unified description of those geometrical structures, with a standard criterion of naturalness, and then we establish relationships among them and try to clarify the meaning of associated geometric magnitudes.Comment: To appear in the AIP Conference Proceedings of the XVI International Fall Workshop on Geometry and Physics, Lisbon - Portugal, 5-8 September 2007. 5 page

Participación estudiantil salesiana

La participación estudiantil salesiana no es solamente una presencia en un contexto ya dado, sino que se caracteriza por la dinamia de sus actores, que buscan cambiar lo establecido, en especial en esta era posmodernista, en la cual la juventud se identifica con la sociedad de consumo y la información, o mejor dicho se está viviendo dentro de estos ámbitos. Conscientes que para lograr este cambio es necesario tener un referente que guíe nuestra experiencia estudiantil, considero que lo más acertado es dirigir nuestra experiencia como estudiantes desde la visión de Don Bosco, plasmado en su Sistema Preventivo, patrimonio que sigue siendo válido como método educativo, a pesar de los cambios habidos en la sociedad, en la familia, en la educación

Effects of a physical activity program on the physical fitness of schoolchildren with ADHD

Este artículo se centra en estudiar los efectos de un programa de actividad física sobre la condición física de un grupo de escolares con TDAH. MÉTODO: Han participado 12 escolares (12 niños), entre los 7 y los 12 años de edad. La condición física se ha medido mediante dinamometría manual, salto horizontal y Course-Navette. El procedimiento ha sido: pre-test, intervención y pos-test. La intervención ha consistido en 2 días a la semana de actividad física, 60 minutos al día, durante 12 semanas. RESULTADOS Y DISCUSIÓN: Se han producido mejoras significativas en condición física [capacidad músculo-esquelética del tren inferior (p=0.037) y capacidad aeróbica (p=0,011)]. CONCLUSIONES: El programa utilizado es eficaz para mejorar la condición física de niños con TDAH

Different shades of working-class : examining Latino/a parents’ decision-making processes regarding enrollment in a parent academy

Schools continue to struggle with increasing parental engagement with families of color from low and working-class backgrounds. Research has found that by building parents’ capacity to effectively navigate school systems and advocate for their children, parents can increase their participation in school-related activities. Yet, scant research has examined the decision-making processes of working-class Latino/a parents when reconciling whether to participate or not in school-sponsored engagement programs. More research is needed to explore the reasons for parent engagement differences among Latino/a parents who belong to the same low-income SES. As such, the purpose of this study is to examine the factors that contribute to working-class Latino/a parents enrolling into a nationally recognized parent academy in a high-poverty, majority Latino/a school district located in South Texas along the U.S.-Mexico border. Using concepts from Hoover-Dempsey and Sandler’s parental involvement model and community cultural wealth to guide the analysis, this study will examine three categories of parents in this district: parents who graduated from the academy, parents who did not graduate, and parents who chose not to enroll in the academy. Using a case study design, I interviewed 36 parents (N=36), including 12 parents from each category, as well as collected document and archival data. This study’s findings highlight the existence of different dimensions of working-class parents. Not all Latino/a working-class parents are the same. That is, not every parent who fits this description shares the same background or experiences. In the United States, these parents might be grouped in the same category, but some of them come to the program with varying degrees of privilege, most notably in regards to education and family supports. The parents in this study with the most privilege were mainly in Group #1, parents who graduated from the program. Districts need to be aware of these privilege differences and recognize how they impact participation. It is necessary in order to avoid forming deficit assumptions of certain subgroups of parents and recognize that some parents have more constraints on their decisions than others. Therefore, districts must think about ways to address the diverse experiences and backgrounds of working-class Latino/a parents in order to avoid creating parental programs that are only engagement in name but involvement in practice.Educational Administratio

Ampliación y especialización del banco de germoplasma del centro de biotecnología de la Universidad Nacional de Loja

Los recursos fitogenéticos y en particular las leguminosas constituyen un patrimonio de la humanidad de valor incalculable y su pérdida es un proceso irreversible que supone una grave amenaza para la estabilidad de los ecosistemas, el desarrollo agrícola y la seguridad alimentaria del mundo. La zona 7 ubicada al sur de la Cordillera ecuatoriana; formada por las provincias de El Oro, Loja y Zamora Chinchipe, limita al sur y al este con el Perú, y al oeste con el océano Pacífico. Tiene una superficie de 40.126 km2, siendo una de las regiones más biodiversas del Ecuador (INEC,2010).Actualmente se evidencia erosión genética de especies leguminosas existentes en esta zona, debido a muchos factores como son; el uso de semillas hibridas con características de elevados rendimientos productivos, lo que ha ocasionado que nuestro agricultor pierda el interés en propagar y conservar sus semillas nativas. El Banco de Germoplasma de la Universidad Nacional de Loja, tiene almacenado un total de 258 accesiones de leguminosas entre ellas; frejol, maní, sarandaja, haba, arveja y soya; este material está siendo evaluado en laboratorio a través de pruebas de germinación y próximamente en campo mediante el refrescamiento. Objetivo

Cycles and interactions : A mathematician among biologists

The backbone of this thesis is the interdisciplinary interaction between dynamic systems theory and a selection of biological problems. Each chapter focuses in one problem, namely plankton dynamics, cell development paths and sleep-wake dynamics. Despite these topics may seem disconnected, they share an important feature: all of them show cyclic behaviour under certain circumstances. In the present thesis we show that cyclic (or chaotic) behaviour is deeply related with plankton biodiversity. We also use cycles to show, in an intuitive way, that Waddington’s epigenetic landscapes (a common visual tool in stem cell research) are poorly defined, and we provide a practical solution to this. Lastly, we provide an algorithm to forecast a transition between synchronized and non-synchronized cyclic systems (such as normal sleep – insomnia, or normal hearth functioning – arrhythmia), with potential applications in medical sciences