Correlating the interstellar magnetic field with protostellar jets and its sources

This article combines new CCD polarimetric data with previous information about protostellar objects in a search for correlations involving the interstellar magnetic field. Specifically, we carried out an optical polarimetric study of a sample of 28 fields of 10 X 10 arcmin^2 located in the neighborhood of protostellar jets and randomly spread over the Galaxy. The polarimetry of a large number of field stars is used to estimate both the average and dispersion of the interstellar magnetic field (ISMF) direction in each region. The results of the applied statistical tests are as follows. Concerning the alignment between the jet direction and the interstellar magnetic field, the whole sample does not show alignment. There is, however, a statistically significant alignment for objects of Classes 0 and I. Regarding the interstellar magnetic field dispersion, our sample presents values slightly larger for regions containing T Tauri objects than for those harboring younger protostars. Moreover the ISMF dispersion in regions containing high-mass objects tends to be larger than in those including only low-mass protostars. In our sample, the mean interstellar polarization as a function of the average interstellar extinction in a region reaches a maximum value around 3% for A(V) = 5, after which it decreases. Our data also show a clear correlation of the mean value of the interstellar polarization with the dispersion of the interstellar magnetic field: the larger the dispersion, the smaller the polarization. Based on a comparison of our and previous results, we suggest that the dispersion in regions forming stars is larger than in quiescent regions.Comment: ApJ accepte

Avaliação da temperatura na broca e no osso na furação, métodos experimental e clínico

Este trabalho tem como objetivo avaliar a temperatura gerada no tecido ósseo durante a furação. Foram realizadas visitas a uma clínica para acompanhamento da técnica de implantologia dentária e recolha de imagens termográficas para a leitura da temperatura gerada na broca durante o processo de furação. Simultaneamente foi adotado um procedimento experimental, em quatro blocos da Sawbones com propriedades similares às do osso cortical e trabecular, e diferentes densidades. Os resultados obtidos permitem concluir que um material mais denso atinge maiores valores de temperatura durante um processo de furação, ou seja, a densidade do osso é diretamente proporcional à temperatura. Em relação às temperaturas verificadas na broca, o maior aquecimento é registado na furação de ossos mais densos. Na prática clínica os valores médios de temperatura da broca são inferiores aos realizados na experiência laboratorial, pois o processo ocorre com irrigação de fluidos

Levantamento da composição da matovegetação e florística nativa em quintais diversificados.

O solo é componente chave no processo de produção de alimentos e fibras. A produtividade de quintais agroflorestais está diretamente relacionada com a manutenção e/ou construção da fertilidade do solo

Avaliação térmica provocada pela furação no tecido ósseo

Este trabalho tem como objetivo avaliar o efeito da temperatura no osso devido ao aquecimento provocado pelo processo de furação. Foram realizadas visitas a duas clínicas para acompanhamento da técnica de implantologia dentária e recolhidas imagens termográficas para a leitura da temperatura gerada na broca após o processo de furação. Na colocação de implantes dentários por exemplo, as variáveis que interferem no processo de furação do osso são: a velocidade, o material, o diâmetro, o comprimento e a geometria da ponta da broca. Com este trabalho pretende-se verificar, experimental e numericamente, as variáveis que interferem no aquecimento da estrutura óssea. Para isso, são utilizados materiais compósitos com características similares ao osso cortical e trabecular. A metodologia apresentada revela-se útil e diferenciadora de outros trabalhos, pois são utilizados materiais com características similares aos materiais in vivo. Os métodos experimentais utilizados em laboratório são baseados nas técnicas de termografia e termopares durante a furação dos diferentes materiais. Paralelamente, são utilizados modelos teóricos numéricos, com o recurso à técnica de elementos finitos, para a discussão de resultados. Após a elaboração do trabalho conclui-se que a temperatura na broca é superior à temperatura no osso e aumenta consoante a estrutura do material, isto é, se o material possuir cavidades na sua estrutura a temperatura na broca não é tão elevada como no material compacto

Repeated assessment and practice effects of the written symbol digit modalities test using a short inter-test interval

The Symbol Digit Modalities Test (SDMT) is a widely used instrument to assess information processing speed, attention, visual scanning, and tracking. Considering that repeated evaluations are a common need in neuropsychological assessment routines, we explored test–retest reliability and practice effects of two alternate SDMT forms with a short inter-assessment interval. A total of 123 university students completed the written SDMT version in two different time points separated by a 150-min interval. Half of the participants accomplished the same form in both occasions, while the other half filled different forms. Overall, reasonable test–retest reliabilities were found (r = .70), and the subjects that completed the same form revealed significant practice effects (p < .001, dz = 1.61), which were almost non-existent in those filling different forms. These forms were found to be moderately reliable and to elicit a similar performance across participants, suggesting their utility in repeated cognitive assessments when brief inter-assessment intervals are required.This work was supported by European Union FEDER funds through Programa Operacional Factores de Competitividade (COMPETE) for ADI Project "DoIT-Desenvolvimento e Operacionalizacao da Investigacao de Translacao" ("MyHealth-PPS4"; project no 13853)

Gender asymmetries in Portuguese trade unions: the case of the CGTP-IN

Gender imbalances persist throughout the world, particularly at leadership level, and equally also visible in the case of trade unions. This article focuses on CGTP-IN, the largest Portuguese trade union confederation, and sets out analysis incorporating both figures from this organisation and accounts by female members of CGTP-IN unions. Results confirm the existence of gender asymmetries, especially at the highest leadership levels. Analysis of the discourses of these women leaders reveals some awareness of the influence of gender on professional relations, placing women at a disadvantage, especially where leadership is concerned. Furthermore, four reasons driving the persistence of these gender asymmetries in trade union leadership/decision-making roles were identified: family responsibilities, gendered professional segregation, masculine trade union cultures and traditional gender stereotypes. Nevertheless, the interviewees resist to means of affirmative action such as gender quotas, and instead prefer to prioritise education and raising awareness around gender equality.info:eu-repo/semantics/publishedVersio

Posterior Arthroscopic Subtalar Arthrodesis: Clinical and Radiologic Review of 19 Cases

Arthroscopic subtalar arthrodesis has recently gained popularity in the treatment of primary subtalar or post-traumatic arthritis, coalition, or inflammatory diseases with subtalar arthritis. The present study reports the clinical and radiologic results of 19 patients (19 feet) who underwent posterior arthroscopic subtalar arthrodesis using 2 posterior portals. A total of 19 posterior arthroscopic subtalar arthrodeses (minimum follow-up of 24 months) performed without a bone graft and with 2 parallel screws were prospectively evaluated. The fusion rate was 94% (mean time to fusion 9.8 weeks). Modified American Orthopaedic Foot and Ankle Society ankle-hindfoot scale score (maximum 94 points) improved significantly from 43 to 80 points and the visual analog scale for pain score improved from 7.6 to 1.2. The 12-item short-form physical and mental scores at the last follow-up point were 52.5 and 56.4, respectively. One (5.3%) patient underwent open repeat fusion for nonunion, 2 (10.5%) patients required a second procedure for implant removal, and 1 (5.3%) experienced reversible neuropraxia. In conclusion, posterior arthroscopic subtalar arthrodesis is a safe technique with a good union rate and a small number of complications in patients with no or very little hindfoot deformity.info:eu-repo/semantics/publishedVersio

On the Influence of Magnetic Fields on the Structure of Protostellar Jets

We here present the first results of fully three-dimensional (3-D) MHD simulations of radiative cooling pulsed (time-variable) jets for a set of parameters which are suitable for protostellar outflows. Considering different initial magnetic field topologies in approximate $equipartition$ with the thermal gas, i.e., (i) a longitudinal, and (ii) a helical field, both of which permeating the jet and the ambient medium; and (iii) a purely toroidal field permeating only the jet, we find that the overall morphology of the pulsed jet is not very much affected by the presence of the different magnetic field geometries in comparison to a nonmagnetic calculation. Instead, the magnetic fields tend to affect essentially the detailed structure and emission properties behind the shocks at the head and at the pulse-induced internal knots, particularly for the helical and toroidal geometries. In these cases, we find, for example, that the $H_\alpha$ emissivity behind the internal knots can be about three to four times larger than that of the purely hydrodynamical jet. We also find that some features, like the nose cones that often develop at the jet head in 2-D calculations involving toroidal magnetic fields, are smoothed out or absent in the 3-D calculations.Comment: 13 pages, 3 figures, Accepted by ApJ Letters after minor corrections (for high resolution figures, see http://www.iagusp.usp.br/~adriano/h.tar

Specific configuration of dendritic degeneration in pyramidal neurons of the medial prefrontal cortex induced by differing corticosteroid regimens

We previously demonstrated that hypercorticalism induces pronounced volumetric reductions in the rat medial prefrontal cortex (mPFC) and that these structural changes correlate with deficits in executive function. By applying 3-dimensional analysis of Golgi- Cox--stained material, we now demonstrate that corticosteroids can exert differential effects on dendritic arborizations of pyramidal neurons in lamina II/III of the mPFC. Treatment with the glucocorticoid receptor--selective agonist dexamethasone and with the natural adrenosteroid, corticosterone (CORT), results in significant reductions in the total length of apical dendrites in the pyramidal neurons in lamina II/III of the anterior cingulate/prelimbic and infralimbic cortices. Interestingly, although these treatments do not affect the number of dendritic branches, they are associated with impoverished arborizations in their distal portions and, in CORTtreated animals, with increased branching in the middle portions of the apical dendritic tree. Deprivation of corticosteroids by adrenalectomy leads to decreases in total apical dendritic length and spine number, but in this case, dendritic impoverishment was restricted to the middle/proximal segments of the dendritic trees. None of the treatments influenced the architecture of the basal dendrites. These results add to our knowledge of the morphological substrates through which corticosteroids may disrupt mPFC-dependent behaviors

A NOTE ON TRANSIENT HEAT TRANSFER PROBLEMS WITH TEMPERATURE-DEPENDENT THERMAL CONDUCTIVITY AND THERMAL DIFFUSIVITY

In this work it is presented a numerical procedure for solving transient heat transfer problems in which the thermal diffusivity is strongly dependent on the temperature, with the aid of the Kirchhoff transformation associated to an usual finite difference approach. The first step consists of eliminating the nonlinear terms associated to the derivatives with respect to the position, by means of a Kirchhoff transformation, giving rise to a partial differential equation with only one nonlinear term (involving the coefficient of the derivative with respect to the time). The advance in time is carried out assuming the thermal diffusivity evaluated at a known temperature, giving rise to a semi-implicit scheme. Comparisons between this approach and the usual hypothesis are carried out in order to illustrate the effect of the dependence between the temperature and the thermal diffusivity. Some typical results are presented, based on the (6H-SiC) Silicon Carbide properties