Trabalho : do dever ao direito: uma investigação sobre o desenvolvimento do direito do trabalho no Brasil

Orientadora: Thereza Cristina Gosdal; coorientador: Luís Fernando Lopes PereiraMonografia (graduação) - Universidade Federal do Paraná, Setor de Ciências Jurídicas, Curso de Graduação em DireitoResumo: A consolidação do Direito do Trabalho no Brasil está relacionada com o progresso econômico e com o desenvolvimento do modo de produção capitalista em território nacional. O crescimento industrial e a expansão do trabalho assalariado reclamavam instrumentos capazes de regular as relações produtivas. Surgiram, então, as primeiras normas trabalhistas que, após alguns anos, assumiram status constitucional. Com a solidificação do capitalismo, as relações de trabalho adquiriram uma relevância tal, que as diversas Constituições brasileiras ocuparamse deste tema. As mudanças sociais e econômicas ocorridas no país ao longo das últimas décadas foram responsáveis por uma alteração de paradigma acerca do trabalho, que passou, sob a égide constitucional, de "dever" a "direito" socia

DNA Fingerprinting of Pearls to Determine Their Origins

We report the first successful extraction of oyster DNA from a pearl and use it to identify the source oyster species for the three major pearl-producing oyster species Pinctada margaritifera, P. maxima and P. radiata. Both mitochondrial and nuclear gene fragments could be PCR-amplified and sequenced. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay in the internal transcribed spacer (ITS) region was developed and used to identify 18 pearls of unknown origin. A micro-drilling technique was developed to obtain small amounts of DNA while maintaining the commercial value of the pearls. This DNA fingerprinting method could be used to document the source of historic pearls and will provide more transparency for traders and consumers within the pearl industry

Diopside Needles as Inclusions in Demantoid Garnet From Russia: A Raman Microspectrometric Study

Straight, acicular, colorless solid inclusions in demantoid garnet from the Ural Mountains of Russia were investigated by laser Raman microspectrometry. These “needles,” which occur in association with “horsetail” inclusions (curved, fibrous chrysotile), were identified as diopside. This study also demonstrated that Raman analysis is a highly sensitive method for distinguishing even between isomorphous mineral inclusions in gems, that is, minerals with similar crystal structures but different chemical compositions

Gemmological Investigations on Pearls and Emeralds using Neutron Imaging

Gemmology deals with the characterization of coloured stones, diamonds and pearls used in the jewellery sector. As the investigated objects are in general rather valuable, a large variety of non-destructive testing methods (e.g. X-ray luminescence, X-ray tomography, UV/VIS spectroscopy, etc.) is routinely used for their inspection and characterisation. In a joint project of Paul Scherrer Institut (PSI), Swiss Gemmological Institute (SSEF) and the University Freiburg, potential application fields of neutron imaging methods (i.e. radiography, microtomography and neutron grating interferometry) in the characterisation and testing of pearls and emeralds were investigated and compared to already established X-ray methods. Neutron tomography yields results with comparable image quality but a different contrast, highlighting in the case of pearls the regions containing organic and hence hydrogen containing material. As such regions composed of low-Z material can be very hard to distinguish from voids inside an object using X-ray tomography, neutron tomography provides important additional information on the tested object due to its complementary properties. The complementarity between neutron and X-ray data shows also in the case of emeralds, where fissures filled with organic fillers are highlighted in the neutron data, while staying concealed in the X-ray data. Metallic inclusions in the emeralds on the other hand appear much more pronounced in the X-ray data, then using neutron imaging. The utilization of both methods on the same sample yields hence additional information on the composition of different regions within the object

Examination of the microstructure and composition of jadeite jade - a combination of X-ray microtomography and petrographic methods

High-quality jadeite jade is one of the most valuable gemstone materials in the jewellery trade. In addition to colour and translucency, mineralogical homogeneity and the absence of cracks are crucial for the quality of jadeite jade. The last two characteristics were investigated using a combination of petrographic methods and X-ray microtomography. High-quality jade monomineralically consists of jadeite and has a fine, polycrystalline structure. However, such high-quality jade was deliberately avoided for the examinations presented here, as the main aim of this study was the identification of different mineralogical phases by X-ray microtomography and their determination by petrographic methods. The overall goal was to create a database in which each mineralogical phase is assigned a characteristic value corresponding to its attenuation coefficient, in order to use non-destructive X-ray microtomography as a tool for the precise examination of mineralogically inhomogeneous jadeite samples. The attenuation coefficient is a material dependent constant with the unit cm -1, which expresses the ability of a mineral phase to attenuate X-rays. With a computer tomography (CT) scan, the values are presented in shades of grey as a tomogram. If the settings remain the same, these values are comparable for measurements on the same device. Comparing the attenuation coefficients of mineral phases to identify their composition is a well-known technique. For this purpose, a program can be used to visualize the minerals present based on their attenuation values (Bam et al. 2020). However, in addition to the density of the material and the energy of the X-rays, the chemical formula of the minerals must be known, which is not the case for unworked jade specimens. In general, the attenuation coefficient decreases with increasing energy of the X-rays, decreasing density of the material and lower atomic numbers of the elements present in the material (Bam et al. 2020)

Age Determination of Pearls: A New Approach for Pearl Testing and Identification

For this radiocarbon study, 7 saltwater pearls and 3 shells from pearl oysters have been analyzed. The declared ages of the samples range from the mid-19th century to very recent formations. The analyzed data show the potential of the bomb peak time marker to provide additional information when testing pearls. The analyzed pearls could be distinctly separated in pearls of pre- and post-bomb peak ages, in agreement with the distinction based on the declared ages. The analyzed data further reveals the potential of this method to provide supporting evidence for the historic provenience of a pearl or as an indication of a natural or cultured formation of a pearl