22 resultados para Panel Study of Income Dynamics PSID
Resumo:
This communication is part of a larger teaching innovation project financed by the University ofBarcelona, whose objective is to develop and evaluate transversal competences of the UB, learningability and responsibility. The competence is divided into several sub-competencies being the ability toanalyze and synthesis the most intensely worked in the first year. The work presented here part fromthe results obtained in phase 1 and 2 previously implemented in other subjects (Mathematics andHistory) in the first year of the degree of Business Administration Degree. In these subjects’ previousexperiences there were deficiencies in the acquisition of learning skills by the students. The work inthe subject of Mathematics facilitated that students become aware of the deficit. The work on thesubject of History insisted on developing readings schemes and with the practical exercises wassought to go deeply in the development of this competence.The third phase presented here is developed in the framework of the second year degree, in the WorldEconomy subject. The objective of this phase is the development and evaluation of the same crosscompetence of the previous phases, from a practice that includes both, quantitative analysis andcritical reflection. Specifically the practice focuses on the study of the dynamic relationship betweeneconomic growth and the dynamics in the distribution of wealth. The activity design as well as theselection of materials to make it, has been directed to address gaps in the ability to analyze andsynthesize detected in the subjects of the first year in the previous phases of the project.The realization of the practical case is considered adequate methodology to improve the acquisition ofcompetence of the students, then it is also proposed how to evaluate the acquisition of suchcompetence. The practice is evaluated based on a rubric developed in the framework of the projectobjectives. Thus at the end of phase 3 we can analyze the process that have followed the students,detect where they have had major difficulties and identify those aspects of teaching that can help toimprove the acquisition of skills by the students. The interest of this phase resides in the possibility tovalue whether tracing of learning through competences, organized in a collaborative way, is a goodtool to develop the acquisition of these skills and facilitate their evaluation.
Resumo:
The production of transparent exopolymer particles (TEP) in response to several environmental variables was studied in 2 mesocosm experiments. The first (Expt 1) examined a gradient of 4 nutrient levels; the second (Expt 2) examined different conditions of silicate availability and zooplankton presence. Tanks were separated in 2 series, one subjected to turbulence and the other not influenced by turbulence. In tanks with nutrient addition, TEP were rapidly formed, with net apparent production rates closely linked to chl a growth rates, suggesting that phytoplankton cells were actively exuding TEP precursors. High nutrient availability increased the absolute concentration of TEP; however, the relative quantity of TEP produced was found to be lower, as TEP concentration per unit of phytoplankton biomass was inversely related to the initial nitrate dose. In Expt 1, an increase in TEP volume (3 to 48 µm equivalent spherical diameter) with nutrient dose was observed; in Expt 2, both silicate addition and turbulence enhanced TEP production and favored aggregation to larger TEP (>48 µm). The presence of zooplankton lowered TEP concentration and changed the size distribution of TEP, presumably by grazing on TEP or phytoplankton. For lower nutrient concentrations, the ratio of particulate organic carbon (POC) to particulate organic nitrogen (PON) followed the Redfield ratio. At higher nutrient conditions, when nutrients were exhausted during the post-bloom, a decoupling of carbon and nitrogen dynamics occurred and was correlated to TEP formation, with a large flow of carbon channeled toward the TEP pool in turbulent tanks. TEP accounted for an increase in POC concentration of 50% in high-nutrient and turbulent conditions. The study of TEP dynamics is crucial to understanding the biogeochemical response of the aquatic system to forcing variables such as nutrient availability and turbulence intensity.
Resumo:
Aquest document de treball mira d'establir un nou camp d'investigació a la cruïlla entre els fluxos de migració i d'informació i comunicació. Hi ha diversos factors que fan que valgui la pena adoptar aquesta perspectiva. El punt central és que la migració internacional contemporània és incrustada en la dinàmica de la societat de la informació, seguint models comuns i dinàmiques interconnectades. Per consegüent, s'està començant a identificar els fluxos d'informació com a qüestions clau en les polítiques de migració. A més, hi ha una manca de coneixement empíric en el disseny de xarxes d'informació i l'ús de les tecnologies d'informació i comunicació en contextos migratoris. Aquest document de treball també mira de ser una font d'hipòtesis per a investigacions posteriors.
Resumo:
Background: The use of emergency hospital services (EHS) has increased steadily in Spain in the last decade while the number of immigrants has increased dramatically. Studies show that immigrants use EHS differently than native-born individuals, and this work investigates demographics, diagnoses and utilization rates of EHS in Lleida (Spain). Methods: Cross-sectional study of all the 96,916 EHS visits by patients 15 to 64 years old, attended during the years 2004 and 2005 in a public teaching hospital. Demographic data, diagnoses of the EHS visits, frequency of hospital admissions, mortality and diagnoses at hospital discharge were obtained. Utilization rates were estimated by group of origin. Poisson regression was used to estimate the rate ratios of being visited in the EHS with respect to the Spanish-born population. Results: Immigrants from low-income countries use EHS services more than the Spanish-born population. Differences in utilization patterns are particularly marked for Maghrebi men and women and sub-Saharan women. Immigrant males are at lower risk of being admitted to the hospital, as compared with Spanish-born males. On the other hand, immigrant women are at higher risk of being admitted. After excluding the visits with gynecologic and obstetric diagnoses, women from sub-Saharan Africa and the Maghreb are still at a higher risk of being admitted than their Spanish-born counterparts. Conclusion: In Lleida (Spain), immigrants use more EHS than the Spanish born population. Future research should indicate whether the same pattern is found in other areas of Spain and whether EHS use is attributable to health needs, barriers to access to the primary care services or similarities in the way immigrants access health care in their countries of origin.
Resumo:
With the aim of monitoring the dynamics of the Livingston Island ice cap, the Departament de Geodinàmica i Geofísica of the Universitat de Barcelona began ye a r ly surveys in the austral summer of 1994-95 on Johnsons Glacier. During this field campaign 10 shallow ice cores were sampled with a manual ve rtical ice-core drilling machine. The objectives were: i) to detect the tephra layer accumulated on the glacier surface, attributed to the 1970 Deception Island pyroclastic eruption, today interstratified; ii) to verify wheter this layer might serve as a reference level; iii) to measure the 1 3 7Cs radio-isotope concentration accumulated in the 1965 snow stratum; iv) to use the isochrone layer as a mean of verifying the age of the 1970 tephra layer; and, v) to calculate both the equilibrium line of the glacier and average mass balance over the last 28 years (1965-1993). The stratigr a p hy of the cores, their cumulative density curves and the isothermal ice temperatures recorded confi rm that Johnsons Glacier is a temperate glacier. Wi n d, solar radiation heating and liquid water are the main agents controlling the ve rtical and horizontal redistribution of the volcanic and cryoclastic particles that are sedimented and remain interstratified within the g l a c i e r. It is because of this redistribution that the 1970 tephra layer does not always serve as a ve ry good reference level. The position of the equilibrium line altitude (ELA) in 1993, obtained by the 1 3 7Cs spectrometric analysis, varies from about 200 m a.s.l. to 250 m a.s.l. This indicates a rising trend in the equilibrium line altitude from the beginning of the 1970s to the present day. The va rying slope orientation of Johnsons Glacier relative to the prevailing NE wind gives rise to large local differences in snow accumulation, which locally modifies the equilibrium line altitude. In the cores studied, 1 3 7Cs appears to be associated with the 1970 tephra laye r. This indicates an intense ablation episode throughout the sampled area (at least up to 330 m a.s.l), which probably occurred synchronically to the 1970 tephra deposition or later. A rough estimate of the specific mass balance reveals a considerable accumulation gradient related to the increase with altitude.
Resumo:
The marine alkaloid, Lamellarin D (Lam-D), has shown potent cytotoxicity in numerous cancer cell lines, and was recently identified as a potent topoisomerase I inhibitor. A library of open lactone analogs of Lam-D was prepared from a methyl 5,6-dihydropyrrolo[2,1-a]isoquinoline-3- carboxylate scaffold (1) by introducing various aryl groups through sequential and regioselective bromination, followed by Pd(0)-catalyzed Suzuki cross-coupling chemistry. The compounds were obtained in a 24-44% overall yield, and tested in a panel of three human tumor cell lines, MDA-MB- 231 (breast), A-549 (lung), and HT-29 (colon), to evaluate their cytotoxic potential. From these data the SAR study concluded that more than 75% of the open-chain Lam-D analogs tested showed cytotoxicity in a low micromolar GI50 range.
Resumo:
The marine alkaloid, Lamellarin D (Lam-D), has shown potent cytotoxicity in numerous cancer cell lines, and was recently identified as a potent topoisomerase I inhibitor. A library of open lactone analogs of Lam-D was prepared from a methyl 5,6-dihydropyrrolo[2,1-a]isoquinoline-3- carboxylate scaffold (1) by introducing various aryl groups through sequential and regioselective bromination, followed by Pd(0)-catalyzed Suzuki cross-coupling chemistry. The compounds were obtained in a 24-44% overall yield, and tested in a panel of three human tumor cell lines, MDA-MB- 231 (breast), A-549 (lung), and HT-29 (colon), to evaluate their cytotoxic potential. From these data the SAR study concluded that more than 75% of the open-chain Lam-D analogs tested showed cytotoxicity in a low micromolar GI50 range.