986 resultados para Project Selection
Resumo:
El projecte ha estat dedicat a l’elaboració d’una sèrie de recursos didàctics en format digital per a l’ensenyament de les matèries de Geologia Estructural i Tectònica en titulacions universitàries relacionades amb les Ciències de la Terra. L’objectiu és la millora de la formació i del rendiment dels estudiants mitjançant l’elaboració d’activitats de suport no presencials que fomentin l’autoaprenentatge i l’autoregulació per part de l’estudiant. Les activitats intenten aprofitar les noves eines informàtiques disponibles i fomentar l’accés mitjançant la xarxa. El material que s’elabora en el marc del projecte consisteix en: 1) un fons documental d’imatges relacionades amb la Geologia Estructural i la Tectònica amb explicació, disponibles en xarxa i accessibles per motors específics de cerca, 2) un conjunt d’exercicis i casos pràctics, alguns d’ells resolts, i 3) sortides de camp virtuals d’una regió geològica que permeten proposar activitats prèvies a una pràctica presencial de camp o desenvolupar la pràctica a nivell completament autònom. Per aconseguir aquests objectius, les tasques realitzades són: la compilació i digitalització de la base d'imatges d'exemples naturals d'estructures geològiques de deformació de que disposàvem, junt amb la redacció de material explicatiu (text i figures), la selecció d'un conjunt d'exercicis de la disciplina, i la preparació de dades de camp per a la realització de les sortides virtuals. Paral•lelament, aquest material s'ha estat processant per a la seva disposició en xarxa com un recurs lliure y obert, accessible en una website i domini específics (plataforma REDITEC).
Resumo:
L’emergent indústria nanoelectrònica necessita de nous simuladors de dispositius nanoelectrònics. Des del departament d’Enginyeria Electrònica de la UAB se n’està desenvolupant un anomenat BITLLES. Malgrat el seu avançat estat de desenvolupament els manca d’una interfície gràfica que faciliti l’entrada de dades al simulador. Aquest projecte final de carrera s’encarregarà de confeccionar aquesta peça clau per tal de assolir una aplicació prou madura per la seva comercialització. A partir de les tecnologies existents per a la realització d’interfícies es farà una selecció de les eines més adequades pels nostres objectius i seguidament es dissenyarà la interfície gràfica adaptant-la a les necessitats i objectius dels desenvolupadors del projecte BITLLES i dels possibles futurs usuaris.
Resumo:
How cells polarize in response to external cues is a fundamental biological problem. For mating, yeast cells orient growth toward the source of a pheromone gradient produced by cells of the opposite mating type. Polarized growth depends on the small GTPase Cdc42, a central eukaryotic polarity regulator that controls signaling, cytoskeleton polarization, and vesicle trafficking. However, the mechanisms of polarity establishment and mate selection in complex cellular environments are poorly understood. Here we show that, in fission yeast, low-level pheromone signaling promotes a novel polarization state, where active Cdc42, its GEF Scd1, and scaffold Scd2 form colocalizing dynamic zones that sample the periphery of the cell. Two direct Cdc42 effectors--actin cables marked by myosin V Myo52 and the exocyst complex labeled by Sec6 and Sec8--also dynamically colocalize with active Cdc42. However, these cells do not grow due to a block in the exocytosis of cell wall synthases Bgs1 and Bgs4. High-level pheromone stabilizes active Cdc42 zones and promotes cell wall synthase exocytosis and polarized growth. However, in the absence of prior low-level pheromone signaling, exploration fails, and cells polarize growth at cell poles by default. Consequently, these cells show altered partner choice, mating preferentially with sister rather than nonsister cells. Thus, Cdc42 exploration serves to orient growth for partner selection. This process may also promote genetic diversification.
Resumo:
Data analysis, presentation and distribution is of utmost importance to a genome project. A public domain software, ACeDB, has been chosen as the common basis for parasite genome databases, and a first release of TcruziDB, the Trypanosoma cruzi genome database, is available by ftp from ftp://iris.dbbm.fiocruz.br/pub/genomedb/TcruziDB as well as versions of the software for different operating systems (ftp://iris.dbbm.fiocruz.br/pub/unixsoft/). Moreover, data originated from the project are available from the WWW server at http://www.dbbm.fiocruz.br. It contains biological and parasitological data on CL Brener, its karyotype, all available T. cruzi sequences from Genbank, data on the EST-sequencing project and on available libraries, a T. cruzi codon table and a listing of activities and participating groups in the genome project, as well as meeting reports. T. cruzi discussion lists (tcruzi-l@iris.dbbm.fiocruz.br and tcgenics@iris.dbbm.fiocruz.br) are being maintained for communication and to promote collaboration in the genome project
Resumo:
Clone CL Brener is the reference organism used in the Trypanosoma cruzi Genome Project. Some biological parameters of CL Brener were determined: (a) the doubling time of epimastigote forms cultured in liver infusion-tryptose (LIT) medium at 28oC is 58±13 hr; (b) differentiation of epimastigotes to metacyclic trypomastigotes is obtained by incubation in LIT-20% Grace´s medium; (c) trypomastigotes infect mammalian cultured cells and perform the complete intracellular cycle at 33 and 37oC; (d) blood forms are highly infective to mice; (e) blood forms are susceptible to nifurtimox and benznidazole. The molecular typing of CL Brener has been determined: (a) isoenzymatic profiles are characteristic of zymodeme ZB; (b) PCR amplification of a 24Sa ribosomal RNA sequence indicates it belongs to T. cruzi lineage 1; (c) schizodeme, randomly amplified polymorphic DNA (RAPD) and DNA fingerprinting analyses were performed
Resumo:
By using improved pulsed field gel electrophoresis conditions, the molecular karyotype of the reference clone CL Brener selected for Trypanosoma cruzi genome project was established. A total of 20 uniform chromosomal bands ranging in size from 0.45 to 3.5 Megabase pairs (Mbp) were resolved in a single run. The weighted sum of the chromosomal bands was approximately 87 Mbp. Chromoblots were hybridized with 39 different homologous probes, 13 of which identified single chromosomes. Several markers showed linkage and four different linkage groups were identified, each comprising two markers. Densitometric analysis suggests that most of the chromosomal bands contain two or more chromosomes representing either homologous chromosomes and/or heterologous chromosomes with similar sizes
Resumo:
"The host-parasite relationship" is a vast and diverse research field which, despite huge human and financial input over many years, remains largely shrouded in mystery. Clearly, the adaptation of parasites to their different host species, and to the different environmental stresses that they represent, depends on interactions with, and responses to, various molecules of host and/or parasite origin. The schistosome genome project is a primary strategy to reach the goal; this systematic research project has successfully developed novel technologies for qualitative and quantitative characterization of schistosome genes and genome organization by extensive international collaboration between top quality laboratories. Schistosomes are a family of parasitic blood flukes (Phylum Platyhelminthes), which have seven pairs of autosomal chromosomes and one pair of sex chromosomes (ZZ for a male worm and ZW for a female), of a haploid genome size of 2.7x108 base pairs (Simpson et al. 1982). Schistosomes are ideal model organisms for the development of genome mapping strategies since they have a small genome size comparable to that of well-characterized model organisms such as Caenorhabditis elegans (100 Mb) and Drosophila (165 Mb), and contain functional genes with a high level of homology to the host mammalian genes. Here we summarize the current progress in the schistosome genome project, the information of 3,047 transcribed genes (Expressed Sequence Tags; EST), complete sets of cDNA and genomic DNA libraries (including YAC and cosmid libraries) with a mapping technique to the well defined schistosome chromosomes. The schistosome genome project will further identify and characterize the key molecules that are responsible for host-parasite adaptation, i.e., successful growth, development, maturation and reproduction of the parasite within its host in the near future
Resumo:
Random single pass sequencing of cDNA fragments, also known as generation of Expressed Sequence Tags (ESTs), has been highly successful in the study of the gene content of higher organisms, and forms an integral part of most genome projects, with the objective to identify new genes and targets for disease control and prevention and to generate mapping probes. In the Trypanosoma cruzi genome project, EST sequencing has also been a starting point, and here we report data on the first 797 sequences obtained, partly from a CL Brener epimastigote non-normalized library, partly on a normalized library. Only around 30% of the sequences obtained showed similarity with Genbank and dbEST databases, half of which with sequences already reported for T. cruzi.
Resumo:
Aim: The study aims to describe the activities of the Swiss Early Psychosis Project (SWEPP) which was founded in 1999 as a national network to further and disseminate knowledge on early psychosis (EP) and to enhance collaboration between healthcare groups. Methods: The present paper is a detailed account of the initiation and the development of the Swiss network. We describe all activities such as the several educational campaigns that were addressed to primary and secondary care groups since the early days. We also provide an overview of the current status of EP services throughout the country. Results: Today, most regions in Switzerland provide specialized EP inpatient and/or outpatient services with a clinical or combined clinical research approach that targets at-risk and/or first-episode populations. Some more recently initiated EP services have been launched as collaborative models between several local or regional psychiatric services. Conclusions: The increasing number of EP services and experts in Switzerland may mirror the catalyzing contribution of the Swiss Early Psychosis Project in this important field of health care. The country's small size and the increasing density of specialized services provide excellent bases for larger-scale networking activities in the future, both in clinical and research areas.
Resumo:
The reported prevalence of late-life depressive symptoms varies widely between studies, a finding that might be attributed to cultural as well as methodological factors. The EURO-D scale was developed to allow valid comparison of prevalence and risk associations between European countries. This study used Confirmatory Factor Analysis (CFA) and Rasch models to assess whether the goal of measurement invariance had been achieved; using EURO-D scale data collected in 10 European countries as part of the Survey of Health, Ageing and Retirement in Europe (SHARE) (n = 22,777). The results suggested a two-factor solution (Affective Suffering and Motivation) after Principal Component Analysis (PCA) in 9 of the 10 countries. With CFA, in all countries, the two-factor solution had better overall goodness-of-fit than the one-factor solution. However, only the Affective Suffering subscale was equivalent across countries, while the Motivation subscale was not. The Rasch model indicated that the EURO-D was a hierarchical scale. While the calibration pattern was similar across countries, between countries agreement in item calibrations was stronger for the items loading on the affective suffering than the motivation factor. In conclusion, there is evidence to support the EURO-D as either a uni-dimensional or bi-dimensional scale measure of depressive symptoms in late-life across European countries. The Affective Suffering sub-component had more robust cross-cultural validity than the Motivation sub-component.
Resumo:
We study a dynamic model where growth requires both long-term investment and the selection of talented managers. When ability is not ex-ante observable and contracts are incomplete, managerial selection imposes a cost, as managers facing the risk of being replaced tend to choose a sub-optimally low level of long-term investment. This generates a trade-off between selection and investment that has implications for the choice of contractual relationships. Our analysis shows that rigid long-term contracts sacrificing managerial selection may be optimal at early stages of economic development and when access to information is limited. As the economy grows, however, knowledge accumulation increases the return to talent and makes it optimal to adopt flexible contractual relationships, where managerial selection is implemented even at the cost of lower investment. Better institutions, in the form of a richer contracting environment and less severe informational frictions, speed up the transition to short-term relationships.
Resumo:
Three species of flatworms from the genus Echinococcus (E. granulosus, E. multilocularis and E. vogeli) and four strains of E. granulosus (cattle, horse, pig and sheep strains) were analysed by the PCR-SSCP method followed by sequencing, using as targets two non-coding and two coding (one nuclear and one mitochondrial) genomic regions. The sequencing data was used to evaluate hypothesis about the parasite breeding system and the causes of genetic diversification. The calculated recombination parameters suggested that cross-fertilisation was rare in the history of the group. However, the relative rates of substitution in the coding sequences showed that positive selection (instead of purifying selection) drove the evolution of an elastase and neutrophil chemotaxis inhibitor gene (AgB/1). The phylogenetic analyses revealed several ambiguities, indicating that the taxonomic status of the E. granulosus horse strain should be revised
Resumo:
Genetic polymorphism can be maintained over time by negative frequency-dependent (FD) selection induced by Rock-paper-scissors (RPS) social systems. RPS games produce cyclic dynamics, and have been suggested to exist in lizards, insects, isopods, plants, and bacteria. Sexual selection is predicted to accentuate the survival of the future progeny during negative FD survival selection. More specifically, females are predicted to select mates that produce progeny genotypes that exhibit highest survival during survival selection imposed by adult males. However, no empirical evidence demonstrates the existence of FD sexual selection with respect to fitness payoffs of genetic polymorphisms. Here we tested this prediction using the common lizard Zootoca vivipara, a species with three male color morphs (orange, white, yellow) that exhibit morph frequency cycles. In a first step we tested the congruence of the morph frequency change with the predicted change in three independent populations, differing in male color morph frequency and state of the FD morph cycle. Thereafter we ran standardized sexual selection assays in which we excluded alternative mechanisms that potentially induce negative FD selection, and we quantified inter-sexual behavior. The patterns of sexual selection and the observed behavior were in line with context-dependent female mate choice and male behavior played a minor role. Moreover, the strength of the sexual selection was within the magnitude of selection required to produce the observed 3-4-year and 6-8 year morph frequency cycles at low and high altitudes, respectively. In summary, the study provides the first experimental evidence that underpins the crucial assumption of the RPS games suggested to exist in lizards, insects, isopods, and plants; namely, that sexual selection produces negative-FD selection. This indicates that sexual selection, in our study exert by females, might be a crucial driver of the maintenance of genetic polymorphisms.