O uso da argumentação na montagem de um modelo

Trabalhos recentes na área de Ensino de ciência têm tratado a argumentação como parte imprescindível das aulas de ciência, pois argumentar seria uma das características da ciência. A forma de análise recorrente em tais trabalhos é o padrão criado por Toulmin, que permite uma divisão do argumento e a identificação de seus elementos constituintes. Foi analisada uma seqüência didática com as turmas de 3º ano da escola de Aplicação da Universidade de São Paulo que culminou na montagem de um modelo de DNA. Tal montagem foi feita em grupos e as discussões ocorridas durante a tarefa foram gravadas e transcritas. A análise dos discursos mostrou argumentos simples compostos basicamente por dados e conclusão. A atividade se mostra diferente da ciência já que não são defendidos pontos de vista sobre uma questão aberta, mas sim opiniões sobre algo já estabelecido

Massive black holes in high-redshift lyman break galaxies

Several evidences indicate that Lyman Break Galaxies (LBGs) in the Epoch of Reionization (redshift z > 6) might host massive black holes (MBHs). We address this question by using a merger-tree model combined with tight constraints from the 7 Ms Chandra survey and the known high-z super-MBH population. We find that a typical LBG with MUV = -22 residing in an Mh ≈ 1012 M halo at z = 6 host an MBH with mass M ≈ 2 × 108MDepending on the fraction, fseed, of early haloes planted with a direct collapse black hole seed (Mseed = 105M⊙the model suggests two possible scenarios: (i) if fseed = 1, MBHs in LBGs mostly grow by merging and must accrete at a low (λE 10-3) Eddington ratio not to exceed the experimental X-ray luminosity upper bound L∗X = 1042.5erg s-1; (ii) if fseed = 0.05, accretion dominates (λE 0.22) and MBH emission in LBGs must be heavily obscured. In both scenarios the UV luminosity function is largely dominated by stellar emission up to very bright mag,MUV >∼ - 23, with BH emission playing a subdominant role. Scenario (i) poses extremely challenging, and possibly unphysical, requirements on DCBH formation. Scenario (ii) entails testable implications on the physical properties of LBGs involving the FIR luminosity, emission lines, and the presence of outflows

The infrared emission of carbonaceous particles around C-rich IRAS sources

The IRAS spectra of 23 carbon-rich sources have been fitted by means of an improved theoretical model based on the Leung-Spagna radiative transfer code and using extinction data obtained in our laboratory for different types of amorphous carbon and silicon carbide submicron particles. The agreement between observations and theoretical spectra is rather good. However, a comparison between the IRAS spectrum of the object 1244710425 (RU Vir) and that recently obtained at UKIRT, for the same object but with higher resolution, seems to open new problems

O uso da argumentação na montagem de um modelo

Trabalhos recentes na área de Ensino de ciência têm tratado a argumentação como parte imprescindível das aulas de ciência, pois argumentar seria uma das características da ciência. A forma de análise recorrente em tais trabalhos é o padrão criado por Toulmin, que permite uma divisão do argumento e a identificação de seus elementos constituintes. Foi analisada uma seqüência didática com as turmas de 3º ano da escola de Aplicação da Universidade de São Paulo que culminou na montagem de um modelo de DNA. Tal montagem foi feita em grupos e as discussões ocorridas durante a tarefa foram gravadas e transcritas. A análise dos discursos mostrou argumentos simples compostos basicamente por dados e conclusão. A atividade se mostra diferente da ciência já que não são defendidos pontos de vista sobre uma questão aberta, mas sim opiniões sobre algo já estabelecido

04/18/1997 - Collective Soul To Perform At EIU.pdf

International audience► We present a spectroscopic method to discriminate biotic from abiotic carbonates. ► Infrared spectral modifications induced by thermal processing are investigated. ► We analyse carbonate samples with no evidences of biomineralization. ► Our method is a powerful tool for the search of life on Mars

The increasing burden and complexity of multi-morbidity and polypharmacy in geriatric HIV patients: a cross sectional study of people aged 65 - 74 years and more than 75 years

Geriatric Patients Living with HIV/AIDS (GEPPO) is a new prospective observational multicentre cohort consisting of all the HIV-positive geriatric patients being treated at 10 clinics in Italy, and HIV-negative controls attending a single geriatric clinic. The aim of this analysis of the GEPPO cohort was to compare prevalence and risk factors of individual non-communicable diseases (NCD), multi-morbidity (MM) and polypharmacy (PP) amongst HIV positive and HIV negative controls at enrolment into the GEPPO cohort

Reassessing the approach to informed consent: The case of unrelated hematopoietic stem cell transplantation in adult thalassemia patients

Introduction: The informed consent process is the legal embodiment of the fundamental right of the individual to make decisions affecting his or her health., and the patient's permission is a crucial form of respect of freedom and dignity, it becomes extremely important to enhance the patient's understanding and recall of the information given by the physician. This statement acquires additional weight when the medical treatment proposed can potentially be detrimental or even fatal. This is the case of thalassemia patients pertaining to class 3 of the Pesaro classification where Allogenic hematopoietic stem cell transplantation (HSCT) remains the only potentially curative treatment. Unfortunately, this kind of intervention is burdened by an elevated transplantation-related mortality risk (TRM: all deaths considered related to transplantation), equal to 30% according to published reports. In thalassemia, the role of the patient in the informed consent process leading up to HSCT has not been fully investigated. This study investigated the hypothesis that information provided by physicians in the medical scenario of HSCT is not fully understood by patients and that misunderstanding and communication biases may affect the clinical decision-making process.Methods: A questionnaire was either mailed or given personally to 25 patients. A second questionnaire was administered to the 12 physicians attending the patients enrolled in this study. Descriptive statistics were used to evaluate the communication factors.Results: The results pointed out the difference between the risks communicated by physicians and the risks perceived by patients. Besides the study highlighted the mortality risk considered to be acceptable by patients and that considered to be acceptable by physicians.Conclusions: Several solutions have been suggested to reduce the gap between communicated and perceived data. A multi-disciplinary approach may possibly help to attenuate some aspects of communication bias. Several tools have also been proposed to fill or to attenuate the gap between communicated and perceived data. But the most important tool is the ability of the physician to comprehend the right place of conscious consent in the relationship with the patient