The evolution of immigration discourse in the Maltese press from 2005 to 2015: A case study of the Times of Malta

El drama migratorio del cual está siendo Europa testigo en estas últimas semanas es en parte el resultado de una falta de políticas comunitarias en relación a este tema, hecho del cual, en los últimos años, se han hecho eco multitud de medios. Europa, y en especial los países del Mediterráneo, ha experimentado un incremento sustancial en el número de inmigrantes que llegan a sus costas en condiciones cada vez más deplorables y arriesgando gravemente su integridad física. Este hecho está principalmente motivado por el aumento y la intensidad de los conflictos bélicos en países de África y Oriente próximo. En el caso de Malta, un diminuto archipiélago ubicado entre los territorios de Libia y Sicilia, el cambio en la tendencia migratoria que se produjo en 2002 le hizo pasar de ser un país de emigrantes a un país receptor de inmigrantes. Este cambio dio como resultado la aparición de grupos y partidos anti-inmigración, como Azzjoni Nazzjonali, y de un sentimiento de preocupación frente a la llegada de inmigrantes que crece de manera constante según se refleja en encuestas europeas (véase Eurobarometer 82-83). Desde el punto de vista lingüístico, el discurso discriminatorio empleado por los medios de comunicación, organismos y figuras políticas ha sido ampliamente estudiado dentro de la rama del Análisis Crítico del Discurso (Charteris-Black, 2006; Fairclough, 1989, Reisigl & Wodak, 2001; Santa Ana, 1999; Van Dijk, 1984, 1992, 1999, 2000, 2006, Van Leeuwen & Wodak, 1999). En los últimos años, se ha potenciado el uso de un enfoque cognitivo en el análisis de este tipo de discursos. Dicho enfoque utiliza elementos tomados de la lingüística cognitiva para explicar cómo la representación de eventos y participantes en el discurso atiende, o está motivada por la conceptualización mental de dichos eventos y participantes (Charteris-Black, 2006; Hart, 2011; Musolff, 2012; Núñez-Perucha, 2011; O’Brien, 2003; Santa Ana, 1999; Van Dijk, 1992, 1998, 1999, 2000, 2006; Wodak, 2006). El Análisis Crítico del Discurso es una disciplina cuyo principal objetivo es analizar cómo ciertos fenómenos sociales que se basan en relaciones de abuso de poder y dominación se representan en el discurso de las denominadas élites (Van Dijk, 2001). Muchos de estos discursos atienden a lo que en lingüística se ha denominado discurso de discriminación, en donde un grupo dominante ejerce poder sobre otro mediante el uso de diversas herramientas discursivas. Generalmente, estos estudios sobre discursos de discriminación se han centrado en fenómenos como el machismo o el racismo. Dentro de este último campo, cabe destacar el trabajo de Van Dijk en el análisis del discurso del racismo y del discurso de la inmigración (Van Dijk, 1992, 1999, 2000, 2001, 2006). El presente trabajo se centra en analizar cómo la prensa maltesa ha representado el fenómeno de la inmigración y a los inmigrantes desde 2005 hasta 2015. Dentro de esta línea temporal, se presta especial atención al día 2 de abril de 2013. Esta es la fecha en la que la Associated Press, una organización de prensa independiente con subscriptores alrededor del mundo, decidió incluir un importante cambio léxico en su manual de estilo. El motivo del mismo era modificar el uso del adjetivo “ilegal” recomendando su uso para referirse exclusivamente a acciones (ej. Inmigración ilegal) pero nunca para referirse a individuos (ej. Inmigrante ilegal). Nuestro estudio pretende identificar hasta qué punto esta medida se ha puesto en práctica en los periódicos malteses y qué repercusiones ha tenido su incorporación en la representación de los inmigrantes y la inmigración. Para ello, se ha seleccionado como caso de estudio uno de los periódicos en lengua inglesa más leídos en el archipiélago, Times of Malta. El estudio se ha centrado en el análisis de un total de treinta artículos de opinión repartidos de manera homogénea (quince y quince) en dos corpus. El primer corpus contiene artículos pertenecientes a un periodo de tiempo que va desde 2005 hasta la fecha en la cual el cambio léxico de la Associated Press fue publicado, es decir, el 2 de abril de 2013. Por otro lado, el segundo corpus contiene artículos desde el 2 de abril de 2013 hasta mediados de 2015. Para agilizar y facilitar el análisis de los artículos, se ha hecho uso del programa llamado WordSmith Tools, el cual está especializado en el trabajo con corpus. Este programa se utilizó principalmente para analizar la representación semántica de los distintos participantes y eventos. Los resultados del análisis demuestran que el periódico ha aplicado el cambio léxico sugerido por la Associated Press al no encontrarse ningún ejemplo de “inmigrante ilegal” o “migrante ilegal” a partir del 2 de abril de 2013. En estos mismos resultados también se aprecia una representación más positiva de la figura del inmigrante en el segundo corpus, dónde el inmigrante abandona la categoría léxica de “criminal” para comenzar a ser visto cada vez más como la víctima. También a nivel léxico, se puede observar cómo los autores tienden a usar cada vez más el término “migrante” en lugar de “inmigrante”. A pesar de que este último continúa siendo el término más utilizado para referirse a la persona que llega desde otro país, el significativo incremento del uso de la palabra “migrante” en el segundo corpus es llamativo y puede deberse a que la palabra “inmigrante” haya adquirido connotaciones negativas por su repetido uso junto al adjetivo “ilegal”. De entre las estrategias discursivas empleadas en la representación de la sociedad maltesa, cabe destacar dos. Por un lado, tenemos el uso de la victimización, mediante la cual la población maltesa aparece como una víctima frente a la inmigración, que es vista como una amenaza, al mismo tiempo que Malta es también víctima de la falta de apoyo internacional. En segundo lugar, es también común encontrar artículos en donde el autor destaca las cualidades positivas de la sociedad maltesa, especialmente su generosidad. Esta última estrategia es lo que Van Dijk denomina national self-glorifiation (2000:220; 2006:738). En cuanto al uso de las metáforas, el cambio es menos significativo. En general, ambos corpus muestran ejemplos de metáforas en las que el inmigrante aparece conceptualizado como parte de un fenómeno natural incontrolable, un invasor o un organismo dispuesto a infectar o dañar de algún modo el país. En el segundo corpus, sin embargo, desaparecen las metáforas en las que el inmigrante se percibe como un animal inferior, que sí aparecían en el primer corpus. Esto supone un cambio positivo. Hasta este punto hemos resumido los cambios en la representación de los inmigrantes. Respecto al modo en el cual el fenómeno de la inmigración aparece representado en los periódicos, también encontramos cambios importantes. A nivel léxico, el cambio que mencionábamos relativo a los términos “inmigrante” y “migrante” también se produce a la hora de nombrar este fenómeno social. De este modo, la palabra “migración” es más usada en el segundo corpus que en el primero, aunque sigue ocupando el segundo lugar por detrás de la palabra “inmigración”. En cuanto a los contenidos, se puede observar un cambio positivo hacia una mayor concienciación social. Por ejemplo, vemos cómo en el segundo corpus en ocasiones se pide una respuesta estatal a temas como la integración de los inmigrantes o el racismo entre la sociedad, mientras que en el primer corpus la integración era una labor del inmigrante y el racismo era un tema incómodo. En el segundo corpus también encontramos la queja más clara hacia el uso de centros de detención en la isla. En el primer corpus, aunque algunos autores manifestaban su disconformidad con las condiciones en las cuales los inmigrantes vivían dentro de los centros de detención, todos asumían que tener dichos centros era una medida necesaria. Esta especie de consenso social y político acerca del uso de centros de detención se consigue mediante el empleo de herramientas discursivas que representen la inmigración como una amenaza de la cual hay que protegerse (negative other-presentation Van Dijk, 2000:221; 2006:738). En resumen, podemos decir que este trabajo muestra una progresión en el discurso de inmigración en Malta hacia una representación más positiva y amable del inmigrante y de la inmigración. Aunque las limitaciones de este estudio hacen imposible establecer una relación única y directa entre los cambios experimentados por el periódico y el cambio léxico sugerido por la Associated Press, lo cierto es que la descriminalización de los inmigrantes a nivel léxico (mediante la supresión de términos como “ilegal” o “detenidos”) ha influido de manera positiva en el tono y la forma en que este periódico se refiere al fenómeno social de la inmigración

Spatio-temporal intensity dynamics of passively mode-locked fiber laser

We present recent results on measurements of intensity spatio-temporal dynamics in passively mode-locked fibre laser. We experimentally uncover distinct, dynamic and stable spatio-temporal generation regimes of various stochasticity and periodicity properties in though-to-be unstable laser. We present a method to distinguish various types of generated coherent structures, including rogue and shock waves, within the radiation by means of introducing of intensity ACF evolution map. We also discuss how the spectral dynamics could be measured in fiber lasers generating irregular train of pulses of quasi-CW generation via combination of heterodyning and intensity spatio-temporal measurement concept.

Temporal Coding of Volumetric Imagery

'Image volumes' refer to realizations of images in other dimensions such as time, spectrum, and focus. Recent advances in scientific, medical, and consumer applications demand improvements in image volume capture. Though image volume acquisition continues to advance, it maintains the same sampling mechanisms that have been used for decades; every voxel must be scanned and is presumed independent of its neighbors. Under these conditions, improving performance comes at the cost of increased system complexity, data rates, and power consumption.

This dissertation explores systems and methods capable of efficiently improving sensitivity and performance for image volume cameras, and specifically proposes several sampling strategies that utilize temporal coding to improve imaging system performance and enhance our awareness for a variety of dynamic applications.

Video cameras and camcorders sample the video volume (x,y,t) at fixed intervals to gain understanding of the volume's temporal evolution. Conventionally, one must reduce the spatial resolution to increase the framerate of such cameras. Using temporal coding via physical translation of an optical element known as a coded aperture, the compressive temporal imaging (CACTI) camera emonstrates a method which which to embed the temporal dimension of the video volume into spatial (x,y) measurements, thereby greatly improving temporal resolution with minimal loss of spatial resolution. This technique, which is among a family of compressive sampling strategies developed at Duke University, temporally codes the exposure readout functions at the pixel level.

Since video cameras nominally integrate the remaining image volume dimensions (e.g. spectrum and focus) at capture time, spectral (x,y,t,\lambda) and focal (x,y,t,z) image volumes are traditionally captured via sequential changes to the spectral and focal state of the system, respectively. The CACTI camera's ability to embed video volumes into images leads to exploration of other information within that video; namely, focal and spectral information. The next part of the thesis demonstrates derivative works of CACTI: compressive extended depth of field and compressive spectral-temporal imaging. These works successfully show the technique's extension of temporal coding to improve sensing performance in these other dimensions.

Geometrical optics-related tradeoffs, such as the classic challenges of wide-field-of-view and high resolution photography, have motivated the development of mulitscale camera arrays. The advent of such designs less than a decade ago heralds a new era of research- and engineering-related challenges. One significant challenge is that of managing the focal volume (x,y,z) over wide fields of view and resolutions. The fourth chapter shows advances on focus and image quality assessment for a class of multiscale gigapixel cameras developed at Duke.

Along the same line of work, we have explored methods for dynamic and adaptive addressing of focus via point spread function engineering. We demonstrate another form of temporal coding in the form of physical translation of the image plane from its nominal focal position. We demonstrate this technique's capability to generate arbitrary point spread functions.

Finance past, finance future: a brief exploration of the evolution of financial practices

As we work our way through the latest financial crisis, politicians seem both powerless to act convincingly and unable to craft from the welter of diverse and antagonistic narratives a coherent and convincing vision of the future. In this article, we argue that a temporal lens brings clarity to such confusion, and that thinking in terms of time and reflecting on privileged temporal structures helps to highlight underlying assumptions and distinguish different narratives from one another. We begin by articulating our understanding of temporality, and we proceed to apply this to the evolution of financial practice during different historical epochs as recently delineated by Gordon (2012). We argue that the principles of finance were effectively in place by the eighteenth century and that consequent developments are best conceptualized as phases in which one particular aspect is intensified. We find that in different historical periods, the temporal intensification associated with specific models of finance shifts, over history, from the past to the present to the future. We argue that a quite idiosyncratic understanding of the future has been intensified in the present phase, what we refer to as proximal future, and we explain how this has come to be. We then consider the ethical consequences of privileging an intensification of proximal future before mapping an alternative model centred on intensifying distal future, highlighting early signs of its potential emergence in the shadows of our present.

Spectral sensitivity, spatial resolution and temporal resolution and their implications for conspecific signalling in cleaner shrimp.

Cleaner shrimp (Decapoda) regularly interact with conspecifics and client reef fish, both of which appear colourful and finely patterned to human observers. However, whether cleaner shrimp can perceive the colour patterns of conspecifics and clients is unknown, because cleaner shrimp visual capabilities are unstudied. We quantified spectral sensitivity and temporal resolution using electroretinography (ERG), and spatial resolution using both morphological (inter-ommatidial angle) and behavioural (optomotor) methods in three cleaner shrimp species: Lysmata amboinensis, Ancylomenes pedersoni and Urocaridella antonbruunii. In all three species, we found strong evidence for only a single spectral sensitivity peak of (mean ± s.e.m.) 518 ± 5, 518 ± 2 and 533 ± 3 nm, respectively. Temporal resolution in dark-adapted eyes was 39 ± 1.3, 36 ± 0.6 and 34 ± 1.3 Hz. Spatial resolution was 9.9 ± 0.3, 8.3 ± 0.1 and 11 ± 0.5 deg, respectively, which is low compared with other compound eyes of similar size. Assuming monochromacy, we present approximations of cleaner shrimp perception of both conspecifics and clients, and show that cleaner shrimp visual capabilities are sufficient to detect the outlines of large stimuli, but not to detect the colour patterns of conspecifics or clients, even over short distances. Thus, conspecific viewers have probably not played a role in the evolution of cleaner shrimp appearance; rather, further studies should investigate whether cleaner shrimp colour patterns have evolved to be viewed by client reef fish, many of which possess tri- and tetra-chromatic colour vision and relatively high spatial acuity.

A Molecular-scale Programmable Stochastic Process Based On Resonance Energy Transfer Networks: Modeling And Applications

While molecular and cellular processes are often modeled as stochastic processes, such as Brownian motion, chemical reaction networks and gene regulatory networks, there are few attempts to program a molecular-scale process to physically implement stochastic processes. DNA has been used as a substrate for programming molecular interactions, but its applications are restricted to deterministic functions and unfavorable properties such as slow processing, thermal annealing, aqueous solvents and difficult readout limit them to proof-of-concept purposes. To date, whether there exists a molecular process that can be programmed to implement stochastic processes for practical applications remains unknown.

In this dissertation, a fully specified Resonance Energy Transfer (RET) network between chromophores is accurately fabricated via DNA self-assembly, and the exciton dynamics in the RET network physically implement a stochastic process, specifically a continuous-time Markov chain (CTMC), which has a direct mapping to the physical geometry of the chromophore network. Excited by a light source, a RET network generates random samples in the temporal domain in the form of fluorescence photons which can be detected by a photon detector. The intrinsic sampling distribution of a RET network is derived as a phase-type distribution configured by its CTMC model. The conclusion is that the exciton dynamics in a RET network implement a general and important class of stochastic processes that can be directly and accurately programmed and used for practical applications of photonics and optoelectronics. Different approaches to using RET networks exist with vast potential applications. As an entropy source that can directly generate samples from virtually arbitrary distributions, RET networks can benefit applications that rely on generating random samples such as 1) fluorescent taggants and 2) stochastic computing.

By using RET networks between chromophores to implement fluorescent taggants with temporally coded signatures, the taggant design is not constrained by resolvable dyes and has a significantly larger coding capacity than spectrally or lifetime coded fluorescent taggants. Meanwhile, the taggant detection process becomes highly efficient, and the Maximum Likelihood Estimation (MLE) based taggant identification guarantees high accuracy even with only a few hundred detected photons.

Meanwhile, RET-based sampling units (RSU) can be constructed to accelerate probabilistic algorithms for wide applications in machine learning and data analytics. Because probabilistic algorithms often rely on iteratively sampling from parameterized distributions, they can be inefficient in practice on the deterministic hardware traditional computers use, especially for high-dimensional and complex problems. As an efficient universal sampling unit, the proposed RSU can be integrated into a processor / GPU as specialized functional units or organized as a discrete accelerator to bring substantial speedups and power savings.

On the microstructure, growth pattern and original porosity of belemnite rostra: insights from calcitic Jurassic belemnites

Calcitic belemnite rostra are usually employed to perform paleoenvironmental studies based on geochemical data. However, several questions, such as their original porosity and microstructure, remain open, despite they are essential to make accurate interpretations based on geochemical analyses.This paper revisits and enlightens some of these questions. Petrographic data demonstrate that calcite crystals of the rostrum solidum of belemnites grow from spherulites that successively develop along the apical line, resulting in a “regular spherulithic prismatic” microstructure. Radially arranged calcite crystals emerge and diverge from the spherulites: towards the apex, crystals grow until a new spherulite is formed; towards the external walls of the rostrum, the crystals become progressively bigger and prismatic. Adjacent crystals slightly vary in their c-axis orientation, resulting in undulose extinction. Concentric growth layering develops at different scales and is superimposed and traversed by a radial pattern, which results in the micro-fibrous texture that is observed in the calcite crystals in the rostra.Petrographic data demonstrate that single calcite crystals in the rostra have a composite nature, which strongly suggests that the belemnite rostra were originally porous. Single crystals consistently comprise two distinct zones or sectors in optical continuity: 1) the inner zone is fluorescent, has relatively low optical relief under transmitted light (TL) microscopy, a dark-grey color under backscatter electron microscopy (BSEM), a commonly triangular shape, a “patchy” appearance and relatively high Mg and Na contents; 2) the outer sector is non-fluorescent, has relatively high optical relief under TL, a light-grey color under BSEM and low Mg and Na contents. The inner and fluorescent sectors are interpreted to have formed first as a product of biologically controlled mineralization during belemnite skeletal growth and the non-fluorescent outer sectors as overgrowths of the former, filling the intra- and inter-crystalline porosity. This question has important implications for making paleoenvironmental and/or paleoclimatic interpretations based on geochemical analyses of belemnite rostra.Finally, the petrographic features of composite calcite crystals in the rostra also suggest the non-classical crystallization of belemnite rostra, as previously suggested by other authors.

Molecular basis of canalization in an ascidian species complex adapted to different thermal conditions

Canalization is a result of intrinsic developmental buffering that ensures phenotypic robustness under genetic variation and environmental perturbation. As a consequence, animal phenotypes are remarkably consistent within a species under a wide range of conditions, a property that seems contradictory to evolutionary change. Study of laboratory model species has uncovered several possible canalization mechanisms, however, we still do not understand how the level of buffering is controlled in natural populations. We exploit wild populations of the marine chordate Ciona intestinalis to show that levels of buffering are maternally inherited. Comparative transcriptomics show expression levels of genes encoding canonical chaperones such as Hsp70 and Hsp90 do not correlate with buffering. However the expression of genes encoding endoplasmic reticulum (ER) chaperones does correlate. We also show that ER chaperone genes are widely conserved amongst animals. Contrary to previous beliefs that expression level of Heat Shock Proteins (HSPs) can be used as a measurement of buffering levels, we propose that ER associated chaperones comprise a cellular basis for canalization. ER chaperones have been neglected by the fields of development, evolution and ecology, but their study will enhance understanding of both our evolutionary past and the impact of global environmental change.

Molecular basis of canalization in an ascidian species complex adapted to different thermal conditions

Canalization is a result of intrinsic developmental buffering that ensures phenotypic robustness under genetic variation and environmental perturbation. As a consequence, animal phenotypes are remarkably consistent within a species under a wide range of conditions, a property that seems contradictory to evolutionary change. Study of laboratory model species has uncovered several possible canalization mechanisms, however, we still do not understand how the level of buffering is controlled in natural populations. We exploit wild populations of the marine chordate Ciona intestinalis to show that levels of buffering are maternally inherited. Comparative transcriptomics show expression levels of genes encoding canonical chaperones such as Hsp70 and Hsp90 do not correlate with buffering. However the expression of genes encoding endoplasmic reticulum (ER) chaperones does correlate. We also show that ER chaperone genes are widely conserved amongst animals. Contrary to previous beliefs that expression level of Heat Shock Proteins (HSPs) can be used as a measurement of buffering levels, we propose that ER associated chaperones comprise a cellular basis for canalization. ER chaperones have been neglected by the fields of development, evolution and ecology, but their study will enhance understanding of both our evolutionary past and the impact of global environmental change.

Personalized cancer medicine: molecular diagnostics, predictive biomarkers, and drug resistance.

The progressive elucidation of the molecular pathogenesis of cancer has fueled the rational development of targeted drugs for patient populations stratified by genetic characteristics. Here we discuss general challenges relating to molecular diagnostics and describe predictive biomarkers for personalized cancer medicine. We also highlight resistance mechanisms for epidermal growth factor receptor (EGFR) kinase inhibitors in lung cancer. We envisage a future requiring the use of longitudinal genome sequencing and other omics technologies alongside combinatorial treatment to overcome cellular and molecular heterogeneity and prevent resistance caused by clonal evolution.

Intraclonal heterogeneity and distinct molecular mechanisms characterize the development of t(4;14) and t(11;14) myeloma.

We have used whole exome sequencing to compare a group of presentation t(4;14) with t(11;14) cases of myeloma to define the mutational landscape. Each case was characterized by a median of 24.5 exonic nonsynonymous single-nucleotide variations, and there was a consistently higher number of mutations in the t(4;14) group, but this number did not reach statistical significance. We show that the transition and transversion rates in the 2 subgroups are similar, suggesting that there was no specific mechanism leading to mutation differentiating the 2 groups. Only 3% of mutations were seen in both groups, and recurrently mutated genes include NRAS, KRAS, BRAF, and DIS3 as well as DNAH5, a member of the axonemal dynein family. The pattern of mutation in each group was distinct, with the t(4;14) group being characterized by deregulation of chromatin organization, actin filament, and microfilament movement. Recurrent RAS pathway mutations identified subclonal heterogeneity at a mutational level in both groups, with mutations being present as either dominant or minor subclones. The presence of subclonal diversity was confirmed at a single-cell level using other tumor-acquired mutations. These results are consistent with a distinct molecular pathogenesis underlying each subgroup and have important impacts on targeted treatment strategies. The Medical Research Council Myeloma IX trial is registered under ISRCTN68454111.

Challenges in molecular testing in non-small-cell lung cancer patients with advanced disease

Lung cancer diagnostics have progressed greatly in the previous decade. Development of molecular testing to identify an increasing number of potentially clinically actionable genetic variants, using smaller samples obtained via minimally invasive techniques, is a huge challenge. Tumour heterogeneity and cancer evolution in response to therapy means that repeat biopsies or circulating biomarkers are likely to be increasingly useful to adapt treatment as resistance develops. We highlight some of the current challenges faced in clinical practice for molecular testing of EGFR, ALK, and new biomarkers such as PDL1. Implementation of next generation sequencing platforms for molecular diagnostics in non-small-cell lung cancer is increasingly common, allowing testing of multiple genetic variants from a single sample. The use of next generation sequencing to recruit for molecularly stratified clinical trials is discussed in the context of the UK Stratified Medicine Programme and The UK National Lung Matrix Trial.

Spatio-temporal Variability of Atmospheric Ozone over Indian Subcontinent and its Relation to Meteorological Parameters

Ozone present in the atmosphere not only absorbs the biologically harmful ultraviolet radiation but also is an important ingredient of the climate system. The radiative absorption properties of ozone make it a determining factor in the structure of the atmosphere. Ozone in the troposphere has many negative impacts on humans and other living beings. Another significant aspect is the absorption of outgoing infrared radiation by ozone thus acting as a greenhouse gas. The variability of ozone in the atmosphere involves many interconnections with the incoming and outgoing radiation, temperature circulation etc. Hence ozone forms an important part of chemistry-climate as well as radiative transfer models. This aspect also makes the quantification of ozone more important. The discovery of Antarctic ozone hole and the role of anthropogenic activities in causing it made it possible to plan and implement necessary preventive measures. Continuous monitoring of ozone is also necessary to identify the effect of these preventive steps. The reactions involving the formation and destruction of ozone are influenced significantly by the temperature fluctuations of the atmosphere. On the other hand the variations in ozone can change the temperature structure of the atmosphere. Indian subcontinent is a region having large weather and climate variability which is evident from the large interannual variability of monsoon system over the region. Nearly half of Indian region comprises the tropical region. Most of ozone is formed in the tropical region and transported to higher latitudes. The formation and transport of ozone can be influenced by changes in solar radiation and various atmospheric circulation features. Besides industrial activities and vehicular traffic is more due to its large population. This may give rise to an increase in the production of tropospheric ozone which is greenhouse gas. Hence it becomes necessary to monitor the atmospheric ozone over this region. This study probes into the spatial distribution and temporal evolution of ozone over Indian subcontinent and discusses the contributing atmospheric parameters.

Molecular characterization of extended-spectrum cephalosporin-resistance in Escherichia coli in pigs on-farm and from clinical cases throughout Quebec, Canada during 16 years

Le développement de la multirésistance chez Escherichia coli est un problème important en médecine animale et humaine. En outre, l’émergence et la diffusion des déterminants de résistance aux céphalosporines à larges spectres de troisième génération (ESCs) parmi les isolats, incluant des céphalosporines essentielles en médecine humaine (ex. ceftriaxone et ceftiofur), est un problème majeur de santé publique. Cette thèse visait trois objectifs. D’abord étudier la dynamique de la résistance aux antimicrobiens (AMR) ainsi que la virulence et les profils génétiques de la AMR des E. coli isolées de porcs recevant une nourriture post-sevrage supplémentée avec de la chlortétracycline et de la pénicilline G, et, accessoirement, évaluer les effets d'additifs alimentaires sur cette dynamique en prenant pour exemple d'étude un minéral argileux, la clinoptilolite, étant donné son possible lien avec le gène blaCMY-2 qui confère la résistance au ceftiofur. L'objectif suivant était d'investiguer les mécanismes menant à une augmentation de la prévalence du gène blaCMY-2 chez les porcs qui reçoivent de la nourriture médicamentée et qui n'ont pas été exposés au ceftiofur Ici encore,nous avons examiné les effets d’un supplément alimentaire avec un minéral argileux sur ce phénomène. Enfin, notre dernier objectif était d’étudier, dans le temps, les génotypes des isolats cliniques d'E. coli résistant au ceftiofur, isolés de porcs malades au Québec à partir du moment où la résistance au ceftiofur a été rapportée, soit de 1997 jusqu'à 2012. Dans l'étude initiale, la prévalence de la résistance à 10 agents antimicrobiens, incluant le ceftiofur, s’accroît avec le temps chez les E.coli isolées de porcelets sevrés. Une augmentation tardive de la fréquence du gène blaCMY-2, encodant pour la résistance au ceftiofur, et la présence des gènes de virulence iucD et tsh a été observée chez les isolats. La nourriture supplémentée avec de la clinoptilolite a été associée à une augmentation rapide mais, par la suite, à une diminution de la fréquence des gènes blaCMY-2 dans les isolats. En parallèle, une augmentation tardive dans la fréquence des gènes blaCMY-2 et des gènes de virulence iucD et tsh a été observée dans les isolats des porcs contrôles, étant significativement plus élevé que dans les porcs ayant reçu l'additif au jour 28. La diversité, au sein des E. coli positives pour blaCMY-2 , a été observée au regard des profils AMR. Certaines lignées clonales d'E.coli sont devenues prédominantes avec le temps. La lignée clonale du phylotype A prédominait dans le groupe supplémenté, alors que les lignées clonales du phylotype B1, qui possèdent souvent le gène de virulence iucD associé aux ExPEC, prédominaient dans le groupe contrôle. Les plasmides d'incompatibilité (Inc) des groupes, I1, A/C, et ColE, porteurs de blaCMY-2, ont été observés dans les transformants. Parmi les souches cliniques d'E.coli ESC-résistantes, isolées de porcs malades au Québec de 1997 à 2012, blaCMY-2 était le gène codant pour une β-lactamase le plus fréquemment détecté; suivi par blaTEM et blaCTX-M,. De plus, les analyses clonales montrent une grande diversité génétique. Par contre, des isolats d'E. coli avec des profils PFGE identiques ont été retrouvés dans de multiples fermes la même année mais aussi dans des années différentes. La résistance à la gentamicine, kanamycine, chloramphenicol, et la fréquence de blaTEM et de IncA/C diminuent significativement au cour de la période étudiée, alors que la fréquence de IncI1 et de la multirésistance à sept catégories d'agents antimicrobiens augmente significativement avec le temps. L'émergence d'isolats d'E. coli positifs pour blaCTX-M, une β-lactamase à large spectre et produisant des ESBL, a été observée en 2011 et 2012 à partir de lignées clonales distinctes et chez de nombreuses fermes. Ces résultats, mis ensemble, apportent des précisions sur la dissémination de la résistance au ceftiofur dans les E. coli isolées de porcs. Au sein des échantillons prélevés chez les porcs sevrés recevant l'alimentation médicamentée sur une ferme, et pour laquelle une augmentation de la résistance au ceftiofur a été observée, les données révèlent que les souches d'E. coli positives pour blaCMY-2 et résistantes aux ESCs appartenaient à plusieurs lignées clonales différentes arborant divers profils AMR. Le gène blaCMY-2 se répand à la fois horizontalement et clonalement chez ces E. coli. L'ajout de clinoptilotite à la nourriture et le temps après le sevrage influencent la clonalité et la prévalence du gène blaCMY-2 dans les E. coli. Durant les 16 années d'étude, plusieurs lignées clonales différentes ont été observées parmi les souches d'E. coli résistantes au ceftiofur isolées de porc malades de fermes québécoises, bien qu’aucune lignée n'était persistante ou prédominante pendant l'étude. Les résultats suggèrent aussi que le gène blaCMY-2 s'est répandu à la fois horizontalement et clonalement au sein des fermes. De plus, blaCMY-2 est le gène majeur des β-lactamases chez ces isolats. À partir de 2011, nous rapportons l'émergence du gène blaCTX-M dans des lignées génétiques distinctes.

Solidão e Depressão: perspetiva temporal

O presente estudo, propõe-se explorar a relação entre os constructos de solidão e depressão, contribuindo para esclarecer em que medida a primeira pode ser considerada uma entidade diagnóstica separada da depressão ou pelo contrário, apenas percebida na relação com a mesma. Pretendeu-se averiguar se existem indivíduos sem depressão que apresentem significativos níveis de solidão. Nesta análise privilegiamos, ainda, a perspetiva temporal, pretendemos verificar se há diferenças significativas na evolução do sentimento de solidão, após o período intervalar de três meses. Participaram, neste estudo, uma amostra de 60 indivíduos com idades compreendidas entre os 40 e os 86 anos, sendo a média aproximada de 52 anos. Os instrumentos utilizados para recolher os dados foram um breve Questionário Sociodemográfico; a adaptação portuguesa da Escala de Solidão da UCLA e a Escala Geriátrica de Depressão (GDS). Os dados foram submetidos a análise pelos princípios da estatística paramétrica. Neste estudo a fidedignidade global demonstrou ser elevada sendo o valor de Alpha Cronbach’s de 0,939.A hipótese central foi confirmada constatando-se que, apesar de existir uma associação estatisticamente significativa entre a solidão e a depressão, existem indivíduos sem depressão que apresentam elevados níveis de solidão (p>0,001). Não se verificou uma relação de prevalência da solidão no género feminino e a mesma foi maior em grupos etários mais elevados, no entanto, essa diferença não se revelou estatisticamente significativa. Recorrendo aos testes do qui-quadrado da independência; de concordância Kappa de cohen e ao teste t de student, concluiu-se que existe uma associação significativa de concordância moderada entre a solidão, ao longo do tempo. Esta conclusão reforça a análise da manutenção dos níveis de solidão quando não existe intervenção terapêutica específica. / This study aims to explore the relationship between the constructs of loneliness and depression, helping to clarify how far the former can be considered a separate diagnostic entity of depression or on the contrary, only perceived in relation to the same. We sought to determine whether there are individuals without depression who present significant levels of loneliness. In this analysis we also focus on the temporal perspective. We plan to check for statistically significant differences in the evolution of the feeling of loneliness after a three month period. A sample of 60 individuals aged between 40 and 86, with an average age of approximately 52, participated in this study. The instruments used to collect the data were a brief Sociodemographic Questionnaire, the Portuguese adaptation of the UCLA Loneliness Scale and the Geriatric Depression Scale (GDS). The data were subjected to an analysis based on the principles of parametric statistics. In this study the overall reliability proved to be high, Cronbach's alpha value being 0,939. A central hypothesis was confirmed verifying that, although there is a statistically significant association between loneliness and depression, there are individuals without depression presenting high levels of loneliness (p <0.001). There was no ratio of loneliness prevaling in females and the same was higher in older age groups, but this difference did not prove to be statistically significant. Using Cohen’s Kappa chi-square independance and agreement tests; and the Student t test, we concluded that there is a significant association of a moderate correlation in loneliness over time. This reinforces the analysis that loneliness levels are maintained when there is no specific therapeutic intervention.