Actividad de investigación científica con alumnos de nivel medio : un estudio de caso

El trabajo presenta una actividad de investigación científica sobre el tema Cama de Faquir, realizada con alumnos de nivel medio (15 y 17 años) de una escuela estatal, y desarrollado en partes entre la universidad y la escuela. Los alumnos proyectaron la cama de faquir, la construyeron, y estudiaron la presión que un globo soporta sobre ella sin explotar. Participaron activamente en el proceso de aprendizaje y se familiarizaron con la investigación científica. Cambiaron sus concepciones inicial simplista por una más próxima a la realidad sobre la naturaleza de la investigación y empezaron a utilizar con más frecuencia términos científicos. El hecho de que el trabajo fuera en su mayoría desarrollado en el ambiente universitario, ayudó a los alumnos a desmitificar la universidad, proporcionándoles nuevas perspectivas en sus vidas profesionales

1.65 micrometers (H-band) surface photometry of galaxies. III: observations of 558 galaxies with the TIRGO 1.5m telescope

We present near-infrared H-band (1.65 micron) surface photometry of 558 galaxies in the Coma Supercluster and in the Virgo cluster. This data set, obtained with the Arcetri NICMOS3 camera ARNICA mounted on the Gornergrat Infrared Telescope, is aimed at complementing, with observations of mostly early-type objects, our NIR survey of spiral galaxies in these regions, presented in previous papers of this series. Magnitudes at the optical radius, total magnitudes, isophotal radii and light concentration indices are derived. We confirm the existence of a positive correlation between the near-infrared concentration index and the galaxy H-band luminosity. (Tables 1 and 2 are only available in electronic form upon request to [email protected])Comment: 12 pages, 6 figures. Accepted for publication in A&A

Single-incision laparoscopic adnexectomy in an obese patient with previous laparotomies

No case of single-incision laparoscopic surgery in obese patients who had previously undergone multiple midline vertical laparotomies has been described in the literature to date. Hence we report the first case of single-port laparoscopic salpingo-oophorectomy in an obese patient who was affected by a left adnexal mass and who had previously undergone 3 midline vertical laparotomies

Valve-sparing neo-aortic root replacement after Fontan completion for hypoplastic left heart syndrome

Digitalitzat per Artypla

Emergency contraception: unresolved clinical, ethical and legal quandaries still linger

Emergency contraception (EC) has been prescribed for decades, in order to lessen the risk of unplanned and unwanted pregnancy following unprotected intercourse, ordinary contraceptive failure, or rape. EC and the linked aspect of unintended pregnancy undoubtedly constitute highly relevant public health issues, in that they involve women's self-determination, reproductive freedom and family planning. Most European countries regulate EC access quite effectively, with solid information campaigns and supply mechanisms, based on various recommendations from international institutions herein examined. However, there is still disagreement on whether EC drugs should be available without a physician's prescription and on the reimbursement policies that should be implemented. In addition, the rights of health care professionals who object to EC on conscience grounds have been subject to considerable legal and ethical scrutiny, in light of their potential to damage patients who need EC drugs in a timely fashion. Ultimately, reproductive health, freedom and conscience-based refusal on the part of operators are elements that have proven extremely hard to reconcile; hence, it is essential to strike a reasonable balance for the sake of everyone's rights and well-being

GIANO-TNG spectroscopy of red supergiants in the young star cluster RSGC3

The Scutum complex in the inner disk of the Galaxy has a number of young star clusters dominated by red supergiants that are heavily obscured by dust extinction and observable only at infrared wavelengths. These clusters are important tracers of the recent star formation and chemical enrichment history in the inner Galaxy. During the technical commissioning and as a first science verification of the GIANO spectrograph at the Telescopio Nazionale Galileo, we secured high-resolution (R=50,000) near-infrared spectra of five red supergiants in the young Scutum cluster RSGC3. Taking advantage of the full YJHK spectral coverage of GIANO in a single exposure, we were able to measure several tens of atomic and molecular lines that were suitable for determining chemical abundances. By means of spectral synthesis and line equivalent width measurements, we obtained abundances of Fe and iron-peak elements such as Ni, Cr, and Cu, alpha (O, Mg, Si, Ca, Ti), other light elements (C, N, F, Na, Al, and Sc), and some s-process elements (Y, Sr). We found average half-solar iron abundances and solar-scaled [X/Fe] abundance patterns for most of the elements, consistent with a thin-disk chemistry. We found depletion of [C/Fe] and enhancement of [N/Fe], consistent with standard CN burning, and low 12C/13C abundance ratios (between 9 and 11), which require extra-mixing processes in the stellar interiors during the post-main sequence evolution. We also found local standard of rest V(LSR)=106 km/s and heliocentric V(HEL)=90 km/s radial velocities with a dispersion of 2.3 km/s. The inferred radial velocities, abundances, and abundance patterns of RSGC3 are very similar to those previously measured in the other two young clusters of the Scutum complex, RSGC1 and RSGC2, suggesting a common kinematics and chemistry within the Scutum complex

Actividad de investigación científica con alumnos de nivel medio : un estudio de caso

El trabajo presenta una actividad de investigación científica sobre el tema Cama de Faquir, realizada con alumnos de nivel medio (15 y 17 años) de una escuela estatal, y desarrollado en partes entre la universidad y la escuela. Los alumnos proyectaron la cama de faquir, la construyeron, y estudiaron la presión que un globo soporta sobre ella sin explotar. Participaron activamente en el proceso de aprendizaje y se familiarizaron con la investigación científica. Cambiaron sus concepciones inicial simplista por una más próxima a la realidad sobre la naturaleza de la investigación y empezaron a utilizar con más frecuencia términos científicos. El hecho de que el trabajo fuera en su mayoría desarrollado en el ambiente universitario, ayudó a los alumnos a desmitificar la universidad, proporcionándoles nuevas perspectivas en sus vidas profesionales

Determinação da sobrecarga de ferro na talassemia pela IRM hepática e ferritina

Accumulation of iron in thalassemia causes organ damage and reduces patient survival due to heart lesions in the second decade of life. Iron deposits are monitored by direct (biopsy) and indirect methods (ferritin) with sequential data being better than isolated measurements. This paper compares two indirect measurements of iron overload; a single hepatic iron concentration (HIC) by magnetic resonance and mean ferritin levels over four years. A retrospective study of 25 patients from the Centro Regional de Hemoterapia in Ribeirão Preto, Brazil was carried out. High HIC (above 7 mg per gram of dry weight) was found in 20 patients and high mean serum ferritin (above 2500 μg/L) in 10 patients. Stratification into three levels (low, moderate and high) of iron overload gave similar results in both tests. Many other factors influence de degree of iron overload in thalassemia. No correlation was found using a non-parametric statistical test between HIC and mean serum ferritin. Both methods provide better planning of chelation therapy.O acúmulo de ferro na talassemia causa lesões orgânicas e reduz a sobrevida do paciente por lesão cardíaca na segunda década da vida, e tem sido avaliado por medidas diretas (biópsia) e indiretas (ferritina). As medidas isoladas carecem de valor, sendo preferidas as sequenciais. Este trabalho pretende comparar medidas indiretas de sobrecarga de ferro, uma medida da concentração de ferro hepático por ressonância magnética, e a ferritina sérica média dos últimos quatro anos. Trata-se de estudo retrospectivo de 25 pacientes do Centro Regional de Hemoterapia, em Ribeirão Preto, Brasil. Encontrou-se em vinte pacientes ferro hepático acima de 7 mg/g peso seco e ferritina média elevada acima de 2.500 ug/l em dez. Estratificação em três níveis de sobrecarga (leve, moderada e grave) produziu resultados semelhantes em ambos os testes. Vários outros fatores influenciam o grau de sobrecarga de ferro na talassemia. Não houve correlação significativa com aplicação de testes não-paramétricos. Ambos os métodos usados concomitantemente levarão a um melhor planejamento da terapia quelante.FapespCNPqCapes and Fundação Hemocentr

Exploring Brown Dwarf Disks in rho Oph

This paper discusses evidence for and properties of disks associated to brown dwarfs in the star-forming region rho-Oph. We selected nine objects fr om the ISOCAM survey of Bontemps et al. (2001) that have detections in the two mid-infrared bands (6.7 and 14.3 um), relatively low extinction and low luminosity. We present low-resolution near-infrared spectra in the J, H and K bands, and determine for each source spectral type, extinction, effective temperature a nd luminosity by comparing the spectra to those of field dwarfs and to the most recent model stellar atmospheres. The results indicate that eight objects have spectral types M6-M7.5, effective temperature of 2600-2700 K, one has a later spectral type (M8.5) and lower temperature (about 2400 K). The derived extinctions range between Av~2 and 8 mag. The location of the objects on the HR diagram, in spite of the uncertainties of the evolutionary tracks for young objects of substellar mass, indicates that all the objects are very young and have masses below about 0.08 Msun. The coolest object in our sample has mass in the range 8-12 Mjup (0.008-0.012 Msun). In all cases, the mid-infrared excess is consistent with the predictions of mode ls of disks irradiated by the central object, showing that circumstellar disks are commonly associated to young brown dwarfs and plan etary-mass objects. Finally, we discuss possible variations of the disk geometry among different objects, as well as the possibility of using these data to discriminate between various f ormation scenarios.Comment: 15 pages, A&A in press, full resolution color figures for appendix A and B are available at http://www.arcetri.astro.it/~lt/preprints/preprints.htm