Efeitos de manipulações ascendentes e descendentes sobre a comunidade fitoplanctônica em um reservatório eutrófico no semi-árido brasileiro

Top-down (grazing) and bottom-up (nutrient, light) controls are important in freshwater ecosystems regulation. Relative importance of these factors could change in space and time, but in tropical lakes bottom-up regulation has to been appointed as more influent. Present study aimed to test the hypothesis that phytoplankton growths rate in Armando Ribeiro reservoir, a huge eutrophic reservoir in semi-arid region of Rio Grande do Norte state, is more limited by nutrient available then zooplankton grazing pressure. Bioassay was conduced monthly from September (2008) to August (2009) manipulating two levels of nutrients (with/without addition) and two level of grazers (with/without removal). Experimental design was factorial 2X2 with four treatments (X5), (i) control with water and zooplankton from natural spot ( C ), (ii) with nutrient addition ( +NP ), (iii) with zooplankton remove ( -Z ) and (iv) with zooplankton remove and nutrient addition ( -Z+NP ). For bioassay confection transparent plastic bottles (500ml) was incubate for 4 or 5 days in two different depths, Secchi`s depth (high luminosity) and 3 times Secchi`s depth (low luminosity). Water samples were collected from each bottle in begins and after incubates period for chlorophyll a concentration analysis and zoopalnktonic organisms density. Phytoplankton growths rates were calculated. Bifactorial ANOVA was performance to test if had a significant effect (p<0,005) of nutrient addition and grazers remove as well a significant interaction between factors on phytoplankton growths rates. Effect magnitude was calculated the relative importance of each process. Results show that phytoplankton growth was in generally stimulated by nutrient addition, as while zooplankton remove rarely stimulated phytoplankton growth. Some significant interactions happening between nutrient additions and grazers remove on phytoplankton growth. In conclusion this study suggests that in studied reservoir phytoplankton growth is more controlled by ascendent factors than descendent

Salud sexual y reproductiva: aspectos de análisis para el departamento de Casanare

La sexualidad y la reproducción están íntimamente ligadas a la calidad de vida, tanto en el ámbito de lo individual como de lo social, por tanto la salud sexual y reproductiva representa un componente esencial para la evaluación de desarrollo de un país, y un tema prioritario en la agenda política mundial y nacional como lo evidencian los objetivos del milenio y de desarrollo sostenible; aunque el país ha dado enormes avances en el tema, aun se presentan grandes retos para el logro y goce efectivo de los derechos sexuales y reproductivos en la población. El objetivo del presente estudio es describir y analizar algunos indicadores de salud sexual y reproductiva en el departamento de Casanare, en el periodo 2008- 2015. Como metodología se usó un diseño descriptivo trasversal, los datos fueron tomados de Sivigila departamental, Estadísticas DANE y del Instituto Nacional de Salud. Se usó SPSS versión 18 y Excel para el análisis de los datos. Como resultados se encontraron altas tasas de prevalencia e incidencia para VIH, sífilis gestacional, y fecundidad en adolescentes en el departamento de Casanare que sobrepasan los indicadores nacionales y presentan tendencia creciente

High performance and energy-efficient instruction cache design and optimisation for ultra-low-power multi-core clusters

High Energy efficiency and high performance are the key regiments for Internet of Things (IoT) end-nodes. Exploiting cluster of multiple programmable processors has recently emerged as a suitable solution to address this challenge. However, one of the main bottlenecks for multi-core architectures is the instruction cache. While private caches fall into data replication and wasting area, fully shared caches lack scalability and form a bottleneck for the operating frequency. Hence we propose a hybrid solution where a larger shared cache (L1.5) is shared by multiple cores connected through a low-latency interconnect to small private caches (L1). However, it is still limited by large capacity miss with a small L1. Thus, we propose a sequential prefetch from L1 to L1.5 to improve the performance with little area overhead. Moreover, to cut the critical path for better timing, we optimized the core instruction fetch stage with non-blocking transfer by adopting a 4 x 32-bit ring buffer FIFO and adding a pipeline for the conditional branch. We present a detailed comparison of different instruction cache architectures' performance and energy efficiency recently proposed for Parallel Ultra-Low-Power clusters. On average, when executing a set of real-life IoT applications, our two-level cache improves the performance by up to 20% and loses 7% energy efficiency with respect to the private cache. Compared to a shared cache system, it improves performance by up to 17% and keeps the same energy efficiency. In the end, up to 20% timing (maximum frequency) improvement and software control enable the two-level instruction cache with prefetch adapt to various battery-powered usage cases to balance high performance and energy efficiency.

Big data and AI applications for health and research. Co-regulation mechanisms as a prosed solution for data protection law issues

Big data and AI are paving the way to promising scenarios in clinical practice and research. However, the use of such technologies might clash with GDPR requirements. Today, two forces are driving the EU policies in this domain. The first is the necessity to protect individuals’ safety and fundamental rights. The second is to incentivize the deployment of innovative technologies. The first objective is pursued by legislative acts such as the GDPR or the AIA, the second is supported by the new data strategy recently launched by the European Commission. Against this background, the thesis analyses the issue of GDPR compliance when big data and AI systems are implemented in the health domain. The thesis focuses on the use of co-regulatory tools for compliance with the GDPR. This work argues that there are two level of co-regulation in the EU legal system. The first, more general, is the approach pursued by the EU legislator when shaping legislative measures that deal with fast-evolving technologies. The GDPR can be deemed a co-regulatory solution since it mainly introduces general requirements, which implementation shall then be interpretated by the addressee of the law following a risk-based approach. This approach, although useful is costly and sometimes burdensome for organisations. The second co-regulatory level is represented by specific co-regulatory tools, such as code of conduct and certification mechanisms. These tools are meant to guide and support the interpretation effort of the addressee of the law. The thesis argues that the lack of co-regulatory tools which are supposed to implement data protection law in specific situations could be an obstacle to the deployment of innovative solutions in complex scenario such as the health ecosystem. The thesis advances hypothesis on theoretical level about the reasons of such a lack of co-regulatory solutions.

Effect of quantum interference on a three-level atom driven by two laser fields

We study the effect of quantum interference on the population distribution and absorptive properties of a V-type three-level atom driven by two lasers of unequal intensities and different angular frequencies. Three coupling configurations of the lasers to the atom are analysed: (a) both lasers coupled to the same atomic transition, (b) each laser coupled to different atomic transition and (c) each laser coupled to both atomic transitions. Dressed stales for the three coupling configurations are identified, and the population distribution and absorptive properties of the weaker field are interpreted in terms of transition dipole moments and transition frequencies among these dressed states. In particular, we find that in the first two cases there is no population inversion between the bare atomic states, but the population can be trapped in a superposition of the dressed states induced by quantum interference and the stronger held. We show that the trapping of the population, which results from the cancellation of transition dipole moments, does not prevent the weaker field to be coupled to the cancelled (dark) transitions. As a result, the weaker field can be strongly amplified on transparent transitions. In the case of each laser coupled to both atomic transitions the population can be trapped in a linear superposition of the excited bare atomic states leaving the ground state unpopulated in the steady state. Moreover, we find that the absorption rate of the weaker field depends on the detuning of the strong field from the atomic resonances and the splitting between the atomic excited states. When the strong held is resonant to one of the atomic transitions a quasi-trapping effect appears in one of the dressed states. In the quasi-trapping situation all the transition dipole moments are different from zero, which allows the weaker field to be amplified on the inverted transitions. When the strong field is tuned halfway between the atomic excited states, the population is completely trapped in one of the dressed states and no amplification is found for the weaker field.

Development of a mungbean (Vigna radiata) RFLP linkage map and its comparison with lablab (Lablab purpureus) revelas a high level of colinearity between the two genomes

A genetic linkage map of mungbean (Vigna radiata, 2n = 2x = 22) consisting of 255 RFLP loci was developed using a recombinant inbred population of 80 individuals. The population was derived from an intersubspecific cross between the cultivated mungbean variety 'Berken' and a wild mungbean genotype 'ACC 41' (V radiata subsp. sublobata). The total length of the map, which comprised 13 linkage groups, spanned 737.9 cM with an average distance between markers of 3.0 cM and a maximum distance between linked markers of 15.4 cM. The mungbean map was compared to a previously published map of lablab (Lablab purpureus, 2n = 2x = 24) using a common set of 65 RFLP probes. In contrast to some other comparative mapping studies among members of the Fabaceae, where a high level of chromosomal rearrangement has been observed, marker order between mungbean and lablab was found to be highly conserved. However, the two genomes have apparently accumulated a large number of duplications/deletions after they diverged.

Genetic linkage analysis of the lesser grain borer Rhyzopertha dominica identifies two loci that confer high-level resistance to the fumigant phosphine

High levels of inheritable resistance to phosphine in Rhyzopertha dominica have recently, been detected in Australia and hi art effort to isolate the genes responsible For resistance we have used random amplified DNA fingerprinting (RAF) to produce a genetic linkage map of R. dominica. The map consists of 94 dominant DNA markers with art average distance between markers of 4.6 cM and defines nine linkage groups with a total recombination distance of 390.1 cM. We have identified two loci that are responsible for high-level resistance. One provides similar to50x resistance to phosphine while the other provides 12.5x resistance and in combination, the two genes act synergistically to provide a resistance level 250 x greater than that of fully susceptible beetles. The haploid genome size has been determined to be 4.76 x 10(8) bp, resulting in an average physical distance of 1.2 Mbp per map unit. No recombination has been observed between either of the two resistance loci and their adjacent DNA markers in a population of 44 fully resistant F-5 individuals, which indicates that the genes are likely to reside within 0.91 cM (1.1 Mbp) of the DNA markers.

Damage level of the two-spotted spider mite Tetranychus urticae Koch (acari: tetranychidae) in soybeans

Among phytophagous spider mites, the two-spotted spider mite Tetranychus urticae Koch, 1836 is one of the most important agricultural pests, not only because of the damage it causes, but also because it has a wide host range, infesting many commercial crops such as leafy greens, cotton, beans, and soybeans, among others. This study was carried out in a greenhouse of the Faculdade de Ciências Agrárias (FCA) of the Universidade Federal da Grande Dourados (UFGD), located in the city of Dourados, state of Mato Grosso do Sul. The experiment was arranged in a randomized block design with 5 treatments and 4 replicates. The treatments consisted of 5 levels in percentage of chlorotic symptoms (indicating mite damage): 0%, 25%, 50%, 75%, and 100%. All of the characteristics evaluated, except for number of pods per plant, the number of seeds per plant, the total weight (productivity), and the weight of 1000 seeds, were significantly influenced by the different levels of chlorotic symptoms. The economic damage level for the two-spotted spider mite Tetranychus urticae, according to the equation y = 66.63-0.51 x, based on the price of US$ 11.00 per bag of soybeans and a control cost of US$ 16.00, would be 15.80% chlorotic symptoms. At a price of US$ 29.00 per bag with the same control cost, the economic damage level would be 13% of chlorotic symptoms.

Stability of the tree-level vacuum in two Higgs doublet models against charge or CP spontaneous violation

We show that in two Higgs doublet models at tree-level the potential minimum preserving electric charge and CP symmetries, when it exists, is the global one. Furthermore, we derived a very simple condition, involving only the coefficients of the quartic terms of the potential, that guarantees spontaneous CP breaking. (C) 2004 Elsevier B.V. All rights reserved.

A PV panel simulator based on a two quadrant DC/DC power converter with a sliding mode controller

The use of a solar photovoltaic (PV) panel simulator can be a valued tool for the design and evaluation of the several components of a photovoltaic system. This simulator is based on power electronic converter controlled in such a way that will behave as a PV panel. Thus, in this paper a PV panel simulator based on a two quadrant DC/DC power converter is proposed. This topology will allow to achieve fast responses, like suddenly changes in the irradiation and temperature. To control the power converter it will be used a fast and robust sliding mode controller. Therefore, with the proposed system I-V curve simulation of a PV panel is obtained. Experimental results from a laboratory prototype are presented in order to confirm the theoretical operation.

PV inverters for module level applications

Dissertação para obtenção do Grau de Mestre em Energias Renováveis – Conversão Eléctrica e Utilização Sustentáveis

Three-phase three-level current-source converter for EVs fast battery charging systems

This paper presents a three-phase three-level fast battery charger for electric vehicles (EVs) based in a current-source converter (CSC). Compared with the traditional voltage-source converters used for fast battery chargers, the CSC can be seen as a natural buck-type converter, i.e., the output voltage can assume a wide range of values, which varies between zero and the maximum instantaneous value of the power grid phase-to-phase voltage. Moreover, using the CSC it is not necessary to use a dc-dc back-end converter in the battery side, and it is also possible to control the grid current in order to obtain a sinusoidal waveform, and in phase with the power grid voltage (unitary power factor). Along the paper is described in detail the proposed CSC for EVs fast battery charging systems: the circuit topology, the power control theory, the current control strategy and the grid synchronization algorithm. Several simulation results of the EV fast battery charger operating with a maximum power of 50 kW are presented.

Effectiveness of two interventions based on improving patient-practitioner communication on diabetes self-management in patients with low educational level: study protocol of a clustered randomized trial in primary care.

BACKGROUND In the last decades the presence of social inequalities in diabetes care has been observed in multiple countries, including Spain. These inequalities have been at least partially attributed to differences in diabetes self-management behaviours. Communication problems during medical consultations occur more frequently to patients with a lower educational level. The purpose of this cluster randomized trial is to determine whether an intervention implemented in a General Surgery, based in improving patient-provider communication, results in a better diabetes self-management in patients with lower educational level. A secondary objective is to assess whether telephone reinforcement enhances the effect of such intervention. We report the design and implementation of this on-going study. METHODS/DESIGN The study is being conducted in a General Practice located in a deprived neighbourhood of Granada, Spain. Diabetic patients 18 years old or older with a low educational level and inadequate glycaemic control (HbA1c > 7%) were recruited. General Practitioners (GPs) were randomised to three groups: intervention A, intervention B and control group. GPs allocated to intervention groups A and B received training in communication skills and are providing graphic feedback about glycosylated haemoglobin levels. Patients whose GPs were allocated to group B are additionally receiving telephone reinforcement whereas patients from the control group are receiving usual care. The described interventions are being conducted during 7 consecutive medical visits which are scheduled every three months. The main outcome measure will be HbA1c; blood pressure, lipidemia, body mass index and waist circumference will be considered as secondary outcome measures. Statistical analysis to evaluate the effectiveness of the interventions will include multilevel regression analysis with three hierarchical levels: medical visit level, patient level and GP level. DISCUSSION The results of this study will provide new knowledge about possible strategies to promote a better diabetes self-management in a particularly vulnerable group. If effective, this low cost intervention will have the potential to be easily incorporated into routine clinical practice, contributing to decrease health inequalities in diabetic patients. TRIAL REGISTRATION Clinical Trials U.S. National Institutes of Health, NCT01849731.

Partial melting of basic dykes in the contact aureoles of two shallow-level, gabbro-pyroxenite intrusions, Fuerteventura

THESIS ABSTRACT Low-pressure anatexis of basic dykes gave rise to unusual, zebra-like migmatites, in the contact metamorphic aureoles of two layered gabbro-pyroxenite intrusions, PXl and PX2, in the root zone of an ocean island, Fuerteventura Basal Complex (Canary Islands). This thesis focuses on the understanding of processes attributing to the partial melting and formation of these migmatites, characterised by a dense network of closely spaced, millimetre-wide leucocratic segregations with perfectly preserved igneous textures. The presence of fluids are required to decrease the solidus of basic igneous lithologies, to allow partial melting in such aloes-pressure (1-2 kb) environment. An oxygen isotope study was thus carried out on dykes inside and beyond the PX2 aureole, in order to decipher the nature and origin of such fluids. Low or negative δ18O values were obtained for whole rocks and mineral-separates, decreasing towards the contact, with the intrusion itself retaining fairly high values. This trend has been attributed to the advection of meteoric water during magma emplacement, with increasing fluid/rock ratios (higher dyke intensities towards the intrusion acting as fluid-pathways) and higher temperatures promoting increasing exchange during recrystallisation. A comparison of whole rock and mineral major- and trace- element data allowed the redistribution of elements .between different mineral phases and generations, during contact metamorphism and partial melting to be assessed. Certain trace-elements, e.g. Zr, Hf, Y, and REEs, were internally redistributed during contact metamorphic recrystallisation, causing- the enrichment of neocrystallised diopsides compared to relict phenocrysts. This has been assigned to the liberation of trace elements on the breakdown of primary minerals, kaersutite and sphene, on entering the thermal aureole. Major and trace element compositions of minerals in migmatite melanosomes and leucosomes are almost identical, pointing to a syn- or post- solidus reequilibration on cooling of the migmatite terrain. The mineralogical, textural and geochemical evolution of dykes in a contact metamorphic aureole, is recorded around an apophysis of the PX1 intrusion, where there is evidence of incipient partial melting. Hydrothermal mineral pseudomorphs in the outer parts of the aureole are progressively replaced by dry mineral assemblages, with increasingly recrystallised diopside and evidence of partial melting -the extent of which varies from one lithology to another. The appearance of more mafic lithologies towards the intrusion, with lower whole rock SiO2 and mobile element abundances, e.g. Rb, Cs, K, has been explained by the migration and accumulation of feldspathic material into leucosomes outside the samples. A micro-structural study of leucosomes and leucocratic pods, with the aid of high-resolution X-ray computed micro-tomography (HRXµCT), allowing the visualization and quantification of shapes and orientations, was carried out in order to better understand the processes of melt segregation in the PX1 aureole. Leucocratic pods, representing former amygdales, are considered as natural strain ellipsoids. Their short axes are oriented perpendicular to leucosome planes, which sub-parallel the intrusive contact. Leucosomes thus effectively represent foliation planes. This implies that the direction of maximum shortening, during migmatisation, was perpendicular to the orientation of leucosomes, contradicting earlier models that suggest leucosomes represent tension veins. RESUME DE LA THESE Un phénomène rare de fusion partielle de filons basiques à basse pression a été étudié dans les auréoles de contact de deux intrusions litées de gabbro-pyroxénite, PX1 et PX2, localisées dans le soubassement de l'île volcanique de Fuerteventura aux Canaries. Cette anatexie a engendré des migmatites finement zébrées d'aspect très inhabituel, dont les processus de formation ont été étudiés dans le présent travail. Ces roches sont caractérisées par un réseau dense de veinules leucocrates d'épaisseur millimétrique, dont les textures ignées sont parfaitement préservées. La fusion partielle de roches basiques à basse pression (1-2 kbar) requiert la présence d'eau afin d'abaisser le solidus du système à des températures géologiquement réalistes. Une étude comparative des isotopes de l'oxygène a ainsi été menée sur des filons respectivement affectés et non affectés par le métamorphisme de contact, afin de confirmer la présence de ces fluides, de déterminer l'importance de leur interaction avec les roches et leur origine. Des valeurs de δ180 basses ou négatives ont été mesurées sur roche totale et minéraux séparés, décroissantes en direction du contact, alors que l'intrusion elle-même a conservé des valeurs élevées. Ce gradient a été attribué à l'advection d'eau météorique durant la mise en place du magma, les températures les plus élevées favorisant d'autant plus la circulation des fluides et les échanges isotopiques durant la recristallisation des roches. Cette recristallisation engendré une redistribution chimique complète des éléments entre les différentes générations de minéraux résultant du métamorphisme de contact et de l'anatexie, mise en évidence par microanalyse. Certains éléments traces comme Zr, Hf, Y et les REE ont été concentrés dans le diopside néoformé consécutivement à la déstabilisation de minéraux primaires riches en ces éléments comme la kaersutite ou le sphène. Les compositions en éléments majeurs et traces des minéraux des mélanosomes et leucosomes des migmatites sont pratiquement identiques, indiquant une rééquilibration syn- à postsolidus lors du refroidissement de l'auréole de contact. La transformation progressive des filons basiques au niveau de leur minéralogie, textures et composition chimique a pu être observée en détail à l'approche du contact d'une apophyse de l'intrusion PX1. La paragenèse magmatique initiale n'est jamais préservée, les faciès les plus distants du contact étant constitués d'un assemblage pseudomorphique hydrothermal. Ce dernier est progressivement remplacé par des assemblages anhydres incluant du diopside néoformé, puis apparaissent les premiers signes de fusion partielle, dont l'importance varie fortement d'une lithologie à l'autre. L'apparition de faciès plus basiques en direction du contact, avec des teneurs réduites en SiO2 et en éléments incompatibles tels Rb, Cs, K, a été attribuée à l'échappement de leucosomes feldspathiques hors du système. Une étude microstructurale de la distribution spatiale du matériel leucocrate au sein des migmatites par microtomographie X de haute résolution (HRXµCT) a été menée pour mieux comprendre les processus de ségrégation des liquides dans l'auréole de PX1. De petites entités ovoïdes, représentant d'anciennes structures amygdalaires au sein des filons, ont été considérées comme des ellipsoïdes marqueurs de la déformation finie. Leur petit axe est orienté perpendiculairement aux plans définis par les leucosomes, eux-mêmes subparallèles au contact intrusif. Les leucosomes matérialisent donc des plans de clivage. Ainsi, la direction de raccourcissement maximum durant la fusion partielle était perpendiculaire à l'orientation des leucosomes, contrairement à ce qui a été dit dans de précédentes publications, qui suggéraient que les leucosomes représentaient des veines de tension. RESUME DE LA THESE (POUR LE GRAND PUBLIC) L'observation directe du soubassement d'une île volcanique est une occasion rare, accessible dans le «complexe de base » de l'île canarienne de Fuerteventura. Ce dernier a enregistré divers phénomènes magmatiques, métamorphiques et de fusion partielle induits par l'intrusion répétée de magmas alimentant des appareils volcaniques sus jacents, sous forme de petits plutons, essaims de filons et complexes annulaires de gabbros alcalins, pyroxénites, syénites et carbonatites. Dans ce contexte de flux de chaleur élevé, des filons basiques ont subi une fusion partielle au contact de deux intrusions de gabbro-pyroxénite, un phénomène extrêmement rare à une profondeur aussi réduite, estimée à quelque 3-6 km. Les produits de cette fusion partielle sont des liquides très riches en feldspath, concentrés en un réseau dense de veinules blanches (leucosomes) au sein du matériau résiduel sombre non fondu (mélanosome) pour former ce qu'on appelle des migmatites. Outre les aspects pétrologiques liés à la formation de ces migmatites, l'intérêt majeur du phénomène réside dans le fait qu'il puisse représenter la source des magmas évolués parfois observés sur les îles océaniques. A des pressions aussi faibles que dans le soubassement de Fuerteventura (1-2 Kbar), la présence de fluides abondants est nécessaire pour abaisser la température de début de fusion des roches (solidus) à des valeurs géologiquement réalistes. Des expériences ont montré que même en présence de plusieurs %-poids d'eau, une température de 1000°C était encore nécessaire pour obtenir une proportion de liquide équivalente à celle observée sur le terrain, soit 25%. Or les magmas alcalins des îles océaniques, bien qu'hydratés, n'en contiennent de loin pas autant, ce qui implique une source d'eau externe. Une étude isotopique de l'oxygène a été entreprise afin de tester cette hypothèse. Les valeurs obtenues en 5180 sont basses ou négatives et indiquent l'influence d'eau d'origine météorique. Cette eau de pluie se serait infiltrée le long des filons depuis la surface du volcan et les aurait complètement hydrothermalisés en profondeur (situation encore visible à l'extérieur de l'auréole de contact), leur permettant ainsi de stocker l'eau nécessaire à leur fusion partielle ultérieure. L'interaction entre eau de pluie et filons a été d'autant plus importante que ces derniers étaient proches du contact avec l'intrusion, ce qui suggère que la circulation de ces eaux et leur interaction avec les roches a été favorisée par la chaleur fournie par l'intrusion elle-même. Un autre aspect de ce travail s'est focalisé sur la redistribution des éléments traces au sein des minéraux des filons basiques durant le métamorphisme de contact et la fusion partielle. Ainsi, le pyroxène de seconde génération est-il sensiblement enrichi en traces telles Zr, Hf, Y et les terres rares, par rapport au pyroxène magmatique originel, en relation avec la déstabilisation de minéraux primaires riches en ces éléments tels le sphène et la kaersutite. Cependant, les compositions en éléments majeurs et traces des minéraux recristallisés des migmatites sont pratiquement les mêmes dans les leucosomes et les mélanosomes, suggérant une rééquilibration chimique complète durant le refroidissement de ces lithologies. Si certaines migmatites se sont comportées en système chimiquement fermé (hormis l'eau météorique), d'autres filons ont manifestement perdu une partie de leurs leucosomes, ainsi qu'en témoigne leur composition progressivement appauvrie en silice et autres éléments incompatibles mobiles, tels K et Rb à l'approche du contact de l'intrusion. Parallèlement à cette évolution chimique, les paragenèses hydrothermales distantes du contact sont progressivement remplacées par des paragenèses anhydres, puis par l'apparition des premiers leucosomes, tandis que les textures magmatiques initiales sont complètement effacées au profit d'une combinaison de textures magmatique dans les leucosomes et en mosaïque dans les mélanosomes. Enfin, la distribution spatiale des liquides de fusion partielle a été étudiée par microtomographie X de haute résolution, dans des filons contenant des entités ovoïdes leucocrates, sans doute d'anciennes amygdales à zéolites. Ces dernières ont été considérées comme des ellipsoïdes de la déformation finie. L'orientation de leur petit axe, perpendiculaire au plan défini par les veinules de leucosomes, indique que ces derniers représentent des plans de clivage perpendiculaires à la direction de raccourcissement maximum. Ainsi, la ségrégation des liquides de fusion partielle se serait faite dans les plans de compression et non dans des plans de dilatation, contrairement à ce que laisserait penser le sens commun.

Quantum nonlocality in two three-level systems

Recently a new Bell inequality has been introduced by Collins et al. [Phys. Rev. Lett. 88, 040404 (2002)], which is strongly resistant to noise for maximally entangled states of two d-dimensional quantum systems. We prove that a larger violation, or equivalently a stronger resistance to noise, is found for a nonmaximally entangled state. It is shown that the resistance to noise is not a good measure of nonlocality and we introduce some other possible measures. The nonmaximally entangled state turns out to be more robust also for these alternative measures. From these results it follows that two von Neumann measurements per party may be not optimal for detecting nonlocality. For d=3,4, we point out some connections between this inequality and distillability. Indeed, we demonstrate that any state violating it, with the optimal von Neumann settings, is distillable.