14 research outputs found

    Justice derailed : the uncertain fate of Haitian migrants and Dominicans of Haitian descent in the Dominican Republic

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    Over time, the Dominican Republic formalized a more restrictive definition of citizenship by birth. By expanding the interpretation of what it means to be “in transit,” the Dominican Republic began to chip away at its jus soli (right of soil) regime. Given the long history of migration from Haiti to the Dominican Republic and demographic realities, this shift has had a disproportionate impact on individuals of Haitian descent. The redefinition of the jus soli basis for citizenship reached its peak in the now infamous sentence of the Constitutional Tribunal of the Dominican Republic, 168-13. In September 2013, the Constitutional Tribunal issued Sentence 168-13, which retroactively denationalized and effectively rendered stateless many Dominicans of Haitian descent by establishing that children born in the Dominican Republic to those illegally residing in the country were not entitled to citizenship by birth, as their parents were considered to be “in transit.” The Sentence further called for a national regularization plan. In an effort to implement Sentence 168-13, the Dominican government established the National Plan for the Regularization of Foreigners (PNRE). The PNRE is a plan to regularize the status of undocumented migrants in the Dominican Republic, which most notably impacts Haitian migrants. Following international backlash over Sentence 168-13, Dominican Republic President Danilo Medina issued Law 169-14 (Naturalization Law), which provides a pathway to naturalization for those effectively left stateless by the Sentence. This report will detail the problems in the implementation of the PNRE and the Naturalization Law, how various actors were involved in or impacted by the regularization and naturalization processes, and finally, will outline the constraints that may inhibit the work of policy makers and human rights defenders in addressing immigration and citizenship issues going forward

    Kinetic characterization of the oxidation of catecolamines and related compounds by laccase

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    The pathways of melanization and sclerotization of the cuticle in insects are carried out by the action of laccases on dopamine and related compounds. In this work, the laccase action of Trametes versicolor (TvL) on catecholamines and related compounds has been kinetically characterized. Among them, dopamine, L-dopa, L-epinephrine, L-norepinephrine, DL-isoprenaline, L-isoprenaline, DL-α-methyldopa, L-α-methyldopa and L-dopa methylester. A chronometric method has been used, which is based on measuring the lag period necessary to consume a small amount of ascorbic acid, added to the reaction medium. The use of TvL has allowed docking studies of these molecules to be carried out at the active site of this enzyme. The hydrogen bridge interaction between the hydroxyl oxygen at C-4 with His-458, and with the acid group of Asp-206, would make it possible to transfer the electron to the T1 Cu-(II) copper centre of the enzyme. Furthermore, Phe-265 would facilitate the adaptation of the substrate to the enzyme through Π-Π interactions. To kinetically characterize these compounds, we need to take into consideration that, excluding L-dopa, L-α-methyldopa and DL-α-methyldopa, all compounds are in hydrochloride form. Because of this, first we need to kinetically characterize the inhibition by chloride and, after that, calculate the kinetic parameters K M and V max S. From the kinetic data obtained, it appears that the best substrate is dopamine. The presence of an isopropyl group bound to nitrogen (isoprenaline) makes it especially difficult to catalyse. The formation of the ester (L-dopa methyl ester) practically does not affect catalysis. The addition of a methyl group (α-methyl dopa) increases the rate but decreases the affinity for catalysis. L-Epinephrine and L-norepinephrine have an affinity similar to isoprenaline, but faster catalysis, probably due to the greater nucleophilic power of their phenolic hydroxyl

    Enzymatic oxidation of oleuropein and 3-hydroxytyrosol by laccase, peroxidase and tyrosinase.

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    The oxidation of oleuropein and 3‐hydroxytyrosol by oxidases laccase, tyrosinase, and peroxidase has been studied. The use of a spectrophotometric method and another spectrophotometric chronometric method has made it possible to determine the kinetic parameters Vmax and KM for each enzyme. The highest binding affinity was shown by laccase. The antioxidant capacities of these two molecules have been characterized, finding a very similar primary antioxidant capacity between them. Docking studies revealed the optimal binding position, which was the same for the two molecules and was a catalytically active position. Practical applications: One of the biggest environmental problems in the food industry comes from olive oil mill wastewater with a quantity of approximately 30 million tons per year worldwide. In addition, olive pomace, the solid residue obtained from the olive oil production, is rich in hydroxytyrosol and oleuropein and the action of enzymatic oxidases can give rise to products in their reactions that can lead to polymerization. This polymerization can have beneficial effects because it can increase the antioxidant capacity with potential application on new functional foods or as feed ingredients. Tyrosinase, peroxidase, and laccase are the enzymes degrading these important polyphenols. The application of a spectrophotometric method for laccase and a chronometric method, for tyrosinase and peroxidase, allowed us to obtain the kinetic information of their reactions on hydroxytyrosol and oleuropein. The kinetic information obtained could advance in the understanding of the mechanism of these important industrial enzymes

    A chemical survey of exoplanets with ARIEL

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    Thousands of exoplanets have now been discovered with a huge range of masses, sizes and orbits: from rocky Earth-like planets to large gas giants grazing the surface of their host star. However, the essential nature of these exoplanets remains largely mysterious: there is no known, discernible pattern linking the presence, size, or orbital parameters of a planet to the nature of its parent star. We have little idea whether the chemistry of a planet is linked to its formation environment, or whether the type of host star drives the physics and chemistry of the planet’s birth, and evolution. ARIEL was conceived to observe a large number (~1000) of transiting planets for statistical understanding, including gas giants, Neptunes, super-Earths and Earth-size planets around a range of host star types using transit spectroscopy in the 1.25–7.8 ÎŒm spectral range and multiple narrow-band photometry in the optical. ARIEL will focus on warm and hot planets to take advantage of their well-mixed atmospheres which should show minimal condensation and sequestration of high-Z materials compared to their colder Solar System siblings. Said warm and hot atmospheres are expected to be more representative of the planetary bulk composition. Observations of these warm/hot exoplanets, and in particular of their elemental composition (especially C, O, N, S, Si), will allow the understanding of the early stages of planetary and atmospheric formation during the nebular phase and the following few million years. ARIEL will thus provide a representative picture of the chemical nature of the exoplanets and relate this directly to the type and chemical environment of the host star. ARIEL is designed as a dedicated survey mission for combined-light spectroscopy, capable of observing a large and well-defined planet sample within its 4-year mission lifetime. Transit, eclipse and phase-curve spectroscopy methods, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allow us to measure atmospheric signals from the planet at levels of 10–100 part per million (ppm) relative to the star and, given the bright nature of targets, also allows more sophisticated techniques, such as eclipse mapping, to give a deeper insight into the nature of the atmosphere. These types of observations require a stable payload and satellite platform with broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify clouds and monitor the stellar activity. The wavelength range proposed covers all the expected major atmospheric gases from e.g. H2O, CO2, CH4 NH3, HCN, H2S through to the more exotic metallic compounds, such as TiO, VO, and condensed species. Simulations of ARIEL performance in conducting exoplanet surveys have been performed – using conservative estimates of mission performance and a full model of all significant noise sources in the measurement – using a list of potential ARIEL targets that incorporates the latest available exoplanet statistics. The conclusion at the end of the Phase A study, is that ARIEL – in line with the stated mission objectives – will be able to observe about 1000 exoplanets depending on the details of the adopted survey strategy, thus confirming the feasibility of the main science objectives.Peer reviewedFinal Published versio

    Metodologia Espectronodal DeterminĂ­stica para CĂĄlculos de Blindagem de NĂȘutrons usando a Equação de Equação de Transporte Multigrupo Considerando Problemas Bidimensionais na Formulação das Ordenadas Discretas (SN)

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    In this work, we present the most recent numerical results in a nodal approach, which resulted in the development of a new numerical spectral nodal method, based on the spectral analysis of the multigroup, isotropic scattering neutron transport equations in the discrete ordinates (SNS_N) formulation for fixed-source calculations in non-multiplying media (shielding problems). The numerical results refer to simulations of typical problems from the reactor physics field, in rectangular two-dimensional Cartesian geometry, X,YX, Y geometry, and are compared with the traditional Diamond Difference (DDDD) fine-mesh method results, used as a reference, and the spectral coarse-mesh method Green's function (SGFSGF) results.Neste trabalho, apresentamos os mais recentes resultados numĂ©ricos de uma abordagem nodal (malha grossa), que resultou no desenvolvimento de um novo mĂ©todo da classe dos espectro-nodais, na formulação determinĂ­stica das ordenadas discretas (SN), aplicado no cĂĄlculo de transporte de nĂȘutrons multigrupo, considerando problemas de blindagem (fonte-fixa). Estes resultados numĂ©ricos se referem Ă s simulaçÔes de problemas tĂ­picos da ĂĄrea de fĂ­sica de reatores, em geometria bidimensional cartesiana retangular e sĂŁo comparados com o tradicional mĂ©todo de malha fina Diamond Difference (DD), usado como referĂȘncia e o mĂ©todo de malha grossa spectral Green's function (SGF)

    Responding to experienced and anticipated discrimination (READ): anti -stigma training for medical students towards patients with mental illness - study protocol for an international multisite non-randomised controlled study

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    BackgroundStigma and discrimination are a significant public health concern and cause great distress to people with mental illness. Healthcare professionals have been identified as one source of this discrimination. In this article we describe the protocol of an international, multisite controlled study, evaluating the effectiveness of READ, an anti-stigma training for medical students towards patients with mental illness. READ aims to improve students' ability to minimise perceived discriminatory behaviours and increase opportunities for patients, therefore developing the ability of future doctors to address and challenge mental illness related discrimination. READ includes components that medical education research has shown to be effective at improving attitudes, beliefs and understanding.Methods/designREAD training was developed using evidence based components associated with changes in stigma related outcomes. The study will take place in multiple international medical schools across high, middle and low income countries forming part of the INDIGO group network, with 25 sites in total. Students will be invited to participate via email from the lead researcher at each site during their psychiatry placement, and will be allocated to an intervention or a control arm according to their local teaching group at each site. READ training will be delivered solely to the intervention arm. Standardised measures will be used to assess students' knowledge, attitudes and skills regarding discrimination in both the intervention and control groups, at baseline and at follow up immediately after the intervention. Statistical analyses of individual-level data will be conducted using random effects models accounting for clustering within sites to investigate changes in mean or percentages of each outcome, at baseline and immediately after the intervention.DiscussionThis is the first international study across high, middle and low income countries, which will evaluate the effectiveness of training for medical students to respond effectively to patients' experiences and anticipation of discrimination. The results will promote implementation of manualised training that will help future doctors to reduce the impact of mental illness related discrimination on their patients. Limitations of the study are also discussed
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