164 research outputs found

    Direito à proteção de dados pessoais no Brasil e os traços centrais de uma autoridade local de proteção

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    Resumo: Sob a lógica da constitucionalização do direito e através dos aportes da fenomenologia-hermenêutica, intenta-se um estudo jurídico e crítico acerca da futura política pública nacional de proteção de dados pessoais e, sobretudo, da autoridade garantidora desta proteção. Assim, no primeiro item realizou-se uma abordagem acerca dos efeitos da (in)compreensão jurídica da internet à proteção de dados pessoais. Em seguida, o estudo dedicou-se a elucidar os esforços jurídicos e políticos brasileiros para a específica proteção de dados pessoais, especialmente por meio da política pública nacional arquitetada no Projeto de Lei Federal número 5.276/2016. Por fim, sugeriram-se linhas fundacionais de uma “autoridade local” de proteção de dados pessoais, que servirá como garantidora dos direitos previstos na política pública nacional de proteção de dados pessoais. Em conclusão, obteve-se, em termos gerais, que o Brasil encaminha-se para a formação de uma política pública nacional de proteção de dados pessoais, muito embora o debate jurídico ainda seja incipiente, tenha sido prejudicado no ano de 2016 pelas tensões políticas e esteja muito atrasado em relação a Europa. Por outro lado, não obstante a política pública articulada seja nacional, melhor que a autoridade garantidora seja de cunho local, a fim de atender as dimensões territoriais do Brasil e as inúmeras referências, realidades e racionalidades que cada região possui.Palavras-chave: Internet. Proteção de dados pessoais. Política Pública. Autoridade Local de Proteção.  Abstract: Under the logic of constitutionalization of law and through the contributions of phenomenology, tries to be a legal and critical study about the future national public policy for the protection of personal data, above all, the guarantor of this protection. Thus, in the first item an evaluation was made about the effects of the legal (no) understanding of the Internet to the protection of personal data. The study then focused on elucidating the Brazilian legal and political efforts for the specific protection of personal data, especially through the national public policy as outlined in Federal Law Project number 5.276/2016. Finally, the foundational guidelines of a "local authority" for the protection of personal data were suggested, which will serve as a guarantor of the rights foreseen in the national public policy of protection of personal data. In conclusion, it was obtained, in general terms, that Brazil is moving towards the formation of a national public policy for the protection of personal data, although the legal debate is still incipient, was harmed in 2016 by political tensions and is far behind in relation the Europe. On the other hand, despite the articulated public policy being national, it is better that the guarantor authority be of a local nature, in order to take into account the territorial dimensions of Brazil and the innumerable references, realities and rationalities that each region possesses.Keywords: Internet. Protection of personal data. Public Police. Local Protection Authority. Submetido em: 30-03-2017Aprovado em: 14-07-201

    Strain control of a bandwidth-driven spin reorientation in Ca₃Ru₂O₇

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    The layered-ruthenate family of materials possess an intricate interplay of structural, electronic and magnetic degrees of freedom that yields a plethora of delicately balanced ground states. This is exemplified by Ca3Ru2O7, which hosts a coupled transition in which the lattice parameters jump, the Fermi surface partially gaps and the spins undergo a 90∘ in-plane reorientation. Here, we show how the transition is driven by a lattice strain that tunes the electronic bandwidth. We apply uniaxial stress to single crystals of Ca3Ru2O7, using neutron and resonant x-ray scattering to simultaneously probe the structural and magnetic responses. These measurements demonstrate that the transition can be driven by externally induced strain, stimulating the development of a theoretical model in which an internal strain is generated self-consistently to lower the electronic energy. We understand the strain to act by modifying tilts and rotations of the RuO6 octahedra, which directly influences the nearest-neighbour hopping. Our results offer a blueprint for uncovering the driving force behind coupled phase transitions, as well as a route to controlling them

    Tuning of the Ru4+ ground-state orbital population in the 4d(4) Mott insulator Ca2RuO4 achieved by La doping

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    The ground-state orbital occupancy of the Ru4+ ion in Ca2−xLaxRuO4[x = 0, 0.05(1), 0.07(1), and 0.12(1)] was investigated by performing x-ray absorption spectroscopy (XAS) in the vicinity of the O K edge as a function of the angle between the incident beam and the surface of the single-crystal samples. A minimal model of the hybridization between the O 2p states probed at the K edge and the Ru 4d orbitals was used to analyze the XAS data, allowing the ratio of hole occupancies nxy/nyz,zx to be determined as a function of doping and temperature. For the samples displaying a low-temperature insulating ground state (x 0.07), nxy/nyz,zx is found to increase significantly with increasing doping, with increasing temperature acting to further enhance nxy/nyz,zx . For the x = 0.12 sample, which has a metallic ground state, the XAS spectra are found to be independent of temperature and not to be describable by the minimal hybridization model, while being qualitatively similar to the spectra displayed by the x 0.07 samples above their insulating to metallic transitions. To understand the origin of the evolution of the electronic structure of Ca2−xLaxRuO4 across its phase diagram, we have performed theoretical calculations based on a model Hamiltonian, comprising electron-electron correlations, crystal field , and spin-orbit coupling λ, of a Ru-O-Ru cluster, with realistic values used to parametrize the various interactions taken from the literature. Our calculations of the Ru hole occupancy as a function of /λ provide an excellent description of the general trends displayed by the data. In particular they establish that the enhancement of nxy/nyz,zx is driven by significant modifications to the crystal field as the tetragonal distortion of the RuO6 octahedral changes from compressive to tensile with La doping. We have also used our model to show that the hole occupancy of the O 2p and Ru 4d orbitals displays the same general trend as a function of /λ, thus validating the minimal hybridization model used to analyze the data. In essence, our results suggest that the predominant mechanism driving the emergence of the low-temperature metallic phase in La-doped Ca2RuO4 is the structurally induced redistribution of holes within the t2g orbitals, rather than the injection of free carriers

    Therapeutic limitations in tumor-specific CD8+ memory T cell engraftment

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    BACKGROUND: Adoptive immunotherapy with cytotoxic T lymphocytes (CTL) represents an alternative approach to treating solid tumors. Ideally, this would confer long-term protection against tumor. We previously demonstrated that in vitro-generated tumor-specific CTL from the ovalbumin (OVA)-specific OT-I T cell receptor transgenic mouse persisted long after adoptive transfer as memory T cells. When recipient mice were challenged with the OVA-expressing E.G7 thymoma, tumor growth was delayed and sometimes prevented. The reasons for therapeutic failures were not clear. METHODS: OT-I CTL were adoptively transferred to C57BL/6 mice 21 – 28 days prior to tumor challenge. At this time, the donor cells had the phenotypical and functional characteristics of memory CD8+ T cells. Recipients which developed tumor despite adoptive immunotherapy were analyzed to evaluate the reason(s) for therapeutic failure. RESULTS: Dose-response studies demonstrated that the degree of tumor protection was directly proportional to the number of OT-I CTL adoptively transferred. At a low dose of OT-I CTL, therapeutic failure was attributed to insufficient numbers of OT-I T cells that persisted in vivo, rather than mechanisms that actively suppressed or anergized the OT-I T cells. In recipients of high numbers of OT-I CTL, the E.G7 tumor that developed was shown to be resistant to fresh OT-I CTL when examined ex vivo. Furthermore, these same tumor cells no longer secreted a detectable level of OVA. In this case, resistance to immunotherapy was secondary to selection of clones of E.G7 that expressed a lower level of tumor antigen. CONCLUSIONS: Memory engraftment with tumor-specific CTL provides long-term protection against tumor. However, there are several limitations to this immunotherapeutic strategy, especially when targeting a single antigen. This study illustrates the importance of administering large numbers of effectors to engraft sufficiently efficacious immunologic memory. It also demonstrates the importance of targeting several antigens when developing vaccine strategies for cancer

    Selective probing of magnetic order on Tb and Ir sites in stuffed Tb<sub>2+x</sub>Ir<sub>2-x</sub>O<sub>7-y</sub> using resonant X-ray scattering

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    We study the magnetic structure of the ``stuffed" (Tb-rich) pyrochlore iridate Tb2+x_{2+x}Ir2x_{2-x}O7y_{7-y}, using resonant elastic x-ray scattering (REXS). In order to disentangle contributions from Tb and Ir magnetic sublattices, experiments were performed at the Ir L3L_3 and Tb M5M_5 edges, which provide selective sensitivity to Ir 5d5d and Tb 4f4f magnetic moments, respectively. At the Ir L3L_3 edge, we found the onset of long-range k=0{\bf k}={\bf 0} magnetic order below TNIrT_{N}^\text{Ir}\sim\,71\,K, consistent with the expected signal of all-in all-out (AIAO) magnetic order. Using a single-ion model to calculate REXS cross-sections, we estimate an ordered magnetic moment of μ5dIr0.34(3)μB\mu_{5d}^{\text{Ir}} \approx 0.34(3)\,\mu_B at 5\,K. At the Tb M5M_5 edge, long-range k=0{\bf k}={\bf 0} magnetic order appeared below 40\sim40\,K, also consistent with an AIAO magnetic structure on the Tb site. Additional insight into the magnetism of the Tb sublattice is gleaned from measurements at the M5M_5 edge in applied magnetic fields up to 6\,T, which is found to completely suppress the Tb AIAO magnetic order. In zero applied field, the observed gradual onset of the Tb sublattice magnetisation with temperature suggests that it is induced by the magnetic order on the Ir site. The persistence of AIAO magnetic order, despite the greatly reduced ordering temperature and moment size compared to stoichiometric Tb2_{2}Ir2_{2}O7_{7}, for which TNIr=130T_{N}^{\text{Ir}} =130\,K and μ5dIr=0.56μB\mu_{5d}^{\text{Ir}}=0.56\,\mu_B, indicates that stuffing could be a viable means of tuning the strength of electronic correlations, thereby potentially offering a new strategy to achieve topologically non-trivial band crossings in pyrochlore iridates

    Gold Mining in the Peruvian Amazon: Global Prices, Deforestation, and Mercury Imports

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    Many factors such as poverty, ineffective institutions and environmental regulations may prevent developing countries from managing how natural resources are extracted to meet a strong market demand. Extraction for some resources has reached such proportions that evidence is measurable from space. We present recent evidence of the global demand for a single commodity and the ecosystem destruction resulting from commodity extraction, recorded by satellites for one of the most biodiverse areas of the world. We find that since 2003, recent mining deforestation in Madre de Dios, Peru is increasing nonlinearly alongside a constant annual rate of increase in international gold price (∼18%/yr). We detect that the new pattern of mining deforestation (1915 ha/year, 2006–2009) is outpacing that of nearby settlement deforestation. We show that gold price is linked with exponential increases in Peruvian national mercury imports over time (R2 = 0.93, p = 0.04, 2003–2009). Given the past rates of increase we predict that mercury imports may more than double for 2011 (∼500 t/year). Virtually all of Peru's mercury imports are used in artisanal gold mining. Much of the mining increase is unregulated/artisanal in nature, lacking environmental impact analysis or miner education. As a result, large quantities of mercury are being released into the atmosphere, sediments and waterways. Other developing countries endowed with gold deposits are likely experiencing similar environmental destruction in response to recent record high gold prices. The increasing availability of satellite imagery ought to evoke further studies linking economic variables with land use and cover changes on the ground

    Regulation of MMP2 and MMP9 metalloproteinases by FSH and growth factors in bovine granulosa cells

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    Matrix metalloproteinases (MMP) are key enzymes involved in tissue remodeling. Within the ovary, they are believed to play a major role in ovulation, and have been linked to follicle atresia. To gain insight into the regulation of MMPs, we measured the effect of hormones and growth factors on MMP2 and MMP9 mRNA levels in non-luteinizing granulosa cells in serum-free culture. FSH and IGF1 both stimulated estradiol secretion and inhibited MMP2 and MMP9 mRNA abundance. In contrast, EGF and FGF2 both inhibited estradiol secretion but had no effect on MMP expression. At physiological doses, none of these hormones altered the proportion of dead cells. Although we cannot link MMP expression with apoptosis, the specific down regulation by the gonadotropic hormones FSH and IGF1 in vitro suggests that excess MMP2 and MMP9 expression is neither required nor desired for follicle development
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