Cosmological simulations suggest a strong correlation between high optical-depth Lya absorbers, which arise from the intergalactic medium, and 3D mass overdensities on scales of 10-30 h(-1) comoving Mpc. By examining the absorption spectra of similar to 80,000 QSO sight lines over a volume of 0.1 Gpc(3) in the Sloan Digital Sky Survey III (SDSS-III), we have identified an extreme overdensity, BOSS1441, which contains a rare group of strong Lya absorbers at z = 2.32 +/- 0.02. This absorber group is associated with six QSOs at the same redshift on a 30 comoving Mpc scale. Using Mayall/MOSAIC narrowband and broadband imaging, we detect Lya emitters (LAEs) down to 0.7 x L-Ly alpha ' * a and reveal a large-scale structure of LAEs in this field. Our follow-up LBT observations have spectroscopically confirmed 20 galaxies in the density peak. We show that BOSS1441 has an LAE overdensity of 10.8 +/- 2.6 on a 15 comoving Mpc scale, which could collapse to a massive cluster with M greater than or similar to 10(15) M-circle dot at z similar to 0. This overdensity is among the most massive large-scale structures at z similar to 2 discovered to date.

There has been substantial research in recent years on the development dynamics of agglomeration economies - the industrial cluster perspective. However, the industrial cluster literature has tended to neglect the environmental impacts of clustering. Meanwhile, industrial ecology has tackled environmental concerns by promoting a new type of eco-friendly industrial system, eco-industrial park (EIP), that encourage circular flows of materials, energy and by-product exchange between neighbouring firms. Given that these two theories can potentially supplement each other, this doctoral study seeks to build bridges between the industrial cluster literature and the industrial ecology literature in order to address the research question: “how do clustered producers draw on inter-firm collaboration and institutional linkages to undertake holistic environmental upgrading strategies?” This study draws on comparative empirical evidence from the Banwol-Sihwa textiles dyeing cluster and the Yeosu petrochemical cluster in South Korea. Both the industrial clusters show a pattern of gradual environmental upgrading that is termed as ‘collective eco-efficiency’, although specific types of such collective behaviours have become differentiated due to their structural differences. The findings provide three key contributions to industrial ecology: (1) Intra-sectoral inter-firm relationships and regional firm-institutional relationships are much more influential in establishing an EIP than inter-sectoral inter-firm relationships on which industrial ecology has conventionally emphasised. (2) Although industrial ecology has mainly concerned of sectoral heterogeneity within an area, the multiplicity of production stages within an industrial cluster is also an important physical condition in establishing an EIP. (3) The notions of institutional setting and planning that have used in very ambiguous manners in industrial ecology are in essence a type of learning-by-interaction dynamics between local firms and other actors based on regional innovation systems. As for the industrial cluster literature, the findings in this study also suggests three conceptual implications: (1) Most studies addressing environmental issues in the industrial cluster literature have largely ignored the inter-sectoral dimension, the dynamics of collective efficiency is not necessarily limited within a sectoral boundary at least with regard to environmental upgrading. (2) Given that value chains do not necessarily match material flows, anchor tenant’s coordination power over material flows should be highlighted in addition to lead firm’s coordination power over value chains. (3) Regional innovation systems function as institutional ability to balance private benefits and social benefits.

Globular clusters are extreme stellar populations. They have the highest stellar density, and host both the oldest and most metal-poor stellar populations in the Galaxy. Their densities make them excellent testbeds for stellar dynamics, while the properties of their stars allows us to test our understanding of old and metal-poor stellar evolution. This thesis is comprised of three projects studying the two nearest globular clusters, NGC 6397 and Messier 4. By examining high-quality HST photometry of NGC 6397, we have constrained the binary fraction in both the central regions, and beyond the half-light radius. We find a binary fraction of ~0.05 in the core and ~0.015 in the outskirts. In the context of recent N-body simulations by Hurley et al., we interpret the observed binary fraction in the outer field as the primordial binary fraction. This value is lower than typically assumed, and has implications for cluster dynamics and N-body modeling. We report the discovery that young white dwarfs are dynamically hotter than their progenitors. Using the same photometry as mentioned above, and archival HST photometry of Messier 4, we have found that young white dwarfs have an extended radial distribution, and therefore a higher velocity dispersion, compared with older white dwarfs and their progenitors. This implies the existence of a ``natal kick''. Implications for cluster dynamics and stellar evolution are discussed. Finally, we present the spectra of 23 white dwarfs in Messier 4 obtained with the Keck/LRIS and Gemini/GMOS spectrographs. We find that all white dwarfs are of type DA. Assuming the same DA/DB ratio as is observed in the field, the chance of finding no DBs in our sample due to statistical fluctuations is 0.006. This suggests DB formation is suppressed in the cluster environment. Furthermore, we constrain the mass of these white dwarfs by fitting models to the spectral lines. Our best estimate of the masses of the white dwarfs currently forming in Messier 4 is 0.51+/-0.02 M_sun.This extends the empirical constraint on the initial-final mass relation over the entire range of initial masses that could have formed white dwarfs in a Hubble time. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

Diseña un clúster para generación de emprendimientos en la cadena agro productiva de la quinua en la provincia de Chimborazo - Ecuador. El estudio es de tipo descriptivo, correlacional y explicativo. Se trabaja con una muestra de 110 productores de quinua y 11 representantes de agregados y comercio servicios. Los resultados obtenidos indican que, los productores de quinua de los cantones de Colta, Guamote, Guano y Riobamba, cultivan la quinua en sus propios terrenos utilizando tecnología para la labranza, para luego comercializarlo en el mercado local y nacional. La producción de quinua en Chimborazo representa el 26% del total nacional. El rendimiento promedio por Ha es de 1.29 TM/Ha. En el mercado local es incipiente el desarrollo de nuevos productos derivados de la quinua. / Tesis

Campylobacter species are the primary cause of bacterial food-borne diarrhoea worldwide. Comparative genomic analyses of Campylobacter strains reveal genome plasticity providing insight into the evolution of virulence traits. The goal of this study was to identify genes important for infectivity and for naturally occurring variability in phenotypic traits in C. jejuni and C. coli strains. Transcriptome and phenotype analyses were conducted to determine if genetic and phenotypic characteristics could be attributed to the source of the strains. Isolates from water sources had higher biofilm formation than animal strains. Clinical strains had decreased sensitivity to hydrogen peroxide as well as increased adherence and invasion when compared to animal strains. A number of genetic differences were observed; however, without further analysis it is difficult to determine which of these impact virulence in Campylobacter. Ultimately, this project will lead to the identification of markers associated with strains of Campylobacter causing illness.

We present a detailed strong lensing (SL) mass reconstruction of the core of the galaxy cluster MACS J2129.4-0741 (z(cl) = 0.589) obtained by combining high-resolution Hubble Space Telescope photometry from the CLASH (Cluster Lensing And Supernovae survey with Hubble) survey with new spectroscopic observations from the CLASH-VLT (Very Large Telescope) survey. A background bright red passive galaxy at z(sp) = 1.36, sextuply lensed in the cluster core, has four radial lensed images located over the three central cluster members. Further 19 background lensed galaxies are spectroscopically confirmed by our VLT survey, including 3 additional multiple systems. A total of 31 multiple images are used in the lensing analysis. This allows us to trace with high precision the total mass profile of the cluster in its very inner region (R < 100 kpc). Our final lensing mass model reproduces the multiple images systems identified in the cluster core with high accuracy of 0.4 arcsec. This translates to a high-precision mass reconstruction of MACS 2129, which is constrained at a level of 2 per cent. The cluster has Einstein parameter Theta(E) = (29 +/- 4) arcsec and a projected total mass of M-tot (< Theta(E)) = (1.35 +/- 0.03) x 10(14) M-circle dot within such radius. Together with the cluster mass profile, we provide here also the complete spectroscopic data set for the cluster members and lensed images measured with VLT/Visible Multi-Object Spectrograph within the CLASH-VLT survey.

The research work presented in this thesis comprises an electron microscopy and spectroscopy study of crystal defects that relate to the occurrence of different colours in natural and synthetic diamonds. Two principal lines of investigation have been covered, each with its own objective. The first aims to identify the source of brown colour in natural and synthetic diamond and the second to ascertain the distribution of colour inducing point defects in synthetic diamond. An outline of both areas of research is given below.1) Brown colour in natural and synthetic diamondsColour is a physical property that can be very difficult to characterise in diamond and consequently it receives regular attention from scientists working in the gem industry. In this work, the crystal structures of brown and colourless natural type IIa diamonds are compared along with brown coloured synthetic diamonds manufactured using the chemical vapour deposition (CVD) process. Numerous attempts have been made to trace the origin of brown tints in natural diamond, with the most likely sources, dislocations and nitrogen impurities, ruled out through the application of various analytical techniques. Recently more emphasis has been placed on the study of vacancy related defects in natural diamond and their influence on colour. Differences between the annealing characteristics of brown coloured natural and CVD diamonds suggest that the defect or defects responsible for the brown colour might be different for each type of diamond. The focus of this research work is the analysis of vacancy defects of the order of 1nm in size using aberration corrected scanning transmission electron microscopy (AC-STEM). The sub-nanometre size probe afforded by this technique allows such defect structures to be resolved much more readily than with conventional high resolution transmission electron microscopy (HR-TEM). Small-scale contrast variations are apparent in the lattice images of brown diamonds but not of the colourless variety. These features have been compared to simulated phase contrast images of vacancy clusters in diamond.2) Yellow / Green coloured synthetic diamonds grown using metal solvent catalystSynthetic diamonds for jewellery and industrial applications are routinely manufactured under high pressure-temperature (HPHT) conditions that closely resemble those found during the creation of natural diamonds. Although the manufacturing equipment can vary in design, the HPHT process that occurs inside the reaction vessel remains essentially the same. During processing, the carbon source material is dissolved into a molten metal and then precipitated onto tiny seed diamonds that are added to the reaction chamber. Much time and effort has been expended in refining this process to reduce impurities and defects in the finished diamonds. The presence of remnant transition metal atoms (e.g. nickel) in the crystal structure influences the electronic properties and in particular the colour of the diamonds. The position and configuration of these metallic defects has previously been studied by a variety of analytical techniques, including optical absorption-luminescence spectroscopy and electron paramagnetic resonance spectroscopy (EPR). These studies have proposed a number of optically active nickel centres at both substitutional and interstitial sites. Their association with vacancies and nitrogen atoms has also been highlighted. This work uses electron microscopy and spectroscopy to characterise the nickel defects in synthetic type 1b diamonds.

We present the discovery of a very faint stellar system, SMASH 1, that is potentially a satellite of the Large Magellanic Cloud. Found within the Survey of the MAgellanic Stellar History (SMASH), SMASH 1 is a compact (r(h) 9.1(-3.4)(+5.9)pc) and very low luminosity (M-V = -1.0 +/- 0.9, L-V = 10(2.3 +/- 0.4) L-circle dot) stellar system that is revealed by its sparsely populated main sequence and a handful of red giant branch candidate member stars. The photometric properties of these stars are compatible with a metal-poor ([Fe/H] = -2.2) and old (13 Gyr) isochrone located at a distance modulus of similar to 18.8, i.e., a distance of similar to 57 kpc. Situated at 11 degrees.3 from the LMC in projection, its three-dimensional distance from the Cloud is similar to 13 kpc, consistent with a connection to the LMC, whose tidal radius is at least 16 kpc. Although the nature of SMASH 1 remains uncertain, its compactness favors it being a stellar cluster and hence dark-matter free. If this is the case, its dynamical tidal radius is only less than or similar to 19 pc at this distance from the LMC, and smaller than the system's extent on the sky. Its low luminosity and apparent high ellipticity (epsilon = 0.62(-0.21)(+0.17)) with its major axis pointing toward the LMC may well be the tell-tale sign of its imminent tidal demise.

Este trabalho tem como objetivo principal desenvolver um sistema de avaliação de desempenho de clusters, capaz de analisar as vantagens potenciais que um cluster pode oferecer e concluir a respeito do aproveitamento dessas vantagens e dos aspectos que podem ser aprimorados. Para isso, o trabalho se propõe a: (i) identificar os constructos e variáveis que devem ser utilizados para representar as vantagens potenciais que um cluster industrial pode oferecer; (ii) desenvolver um sistema de avaliação do aproveitamento das vantagens potenciais de um cluster, baseado nos constructos e variáveis identificados; (iii) testar o sistema, avaliando o nível de desenvolvimento, no que tange ao aproveitamento de vantagens potenciais em que se encontra o cluster moveleiro do Oeste de Santa Catarina; e (iv) estabelecer um plano para aprimoramento das operações e consolidação do referido cluster. Esta tese está baseada numa abordagem quantitativa e qualitativa, utilizando questionário aplicado em 112 empresas, grupo focado e entrevistas. Uma das principais contribuições desta tese é a proposição de um modelo capaz de avaliar o aproveitamento das vantagens potenciais de um cluster, auxiliando na tomada de decisão dos envolvidos (poder público, instituições de classe, empresas) e melhoria da competitividade das empresas do cluster em relação às empresas externas. Outra contribuição deste trabalho é a proposição de ações que possam aumentar o aproveitamento das vantagens oferecidas às empresas pertencentes ao cluster moveleiro do oeste de Santa Catarina e à sua competitividade. / The main objective of this work is to develop a performance evaluation system of clusters, able of analyzing the potential advantages that a cluster can offer to its member companies and conclude about the use of these advantages and about the aspects which could be improved. Considering this general objective, this work intends: (i) identify the constructs and variables that should be utilized for represent the potential advantages that an industrial cluster can offer; (ii) develop an evaluation system for access the use of the potential advantages of a cluster, based on the constructs and identified variables; (iii) test the system, evaluating the development level of the west of Santa Catarina furniture cluster, regarding the use of the potential advantages, (iv) establish a plan for the improvement of operations and consolidation of the mentioned cluster. This dissertation is based on a qualitative and quantitative approach, comprising a survey involving 112 companies, focus group and interviews. One of the main contributions of this dissertation is the proposal of a model capable of evaluate the use of the potential advantages of a cluster, assisting on the decision making of the stakeholders (government, class association and companies) and competitiveness improvement of the cluster member companies compared to outside companies. Other contribution of this work is the proposal of a plan of actions that could increase the use of the advantages offered to the member companies of the west of Santa Catarina furniture cluster and their respective competitiveness.

O objetivo deste trabalho foi determinar a massa do aglomerado de galáxias RXC J1504-0248, localizado em z = 0.215, através da análise de lentes fracas, e comparar os resultados com aqueles obtidos em trabalhos anteriores através da análise de raios-X. Imagens do aglomerado foram obtidos nas bandas r\', g\' e i\' com o detector GMOS do telescópio Gemini Sul. A partir dessas imagens, contruímos um catálogo de objetos no campo usando o software Sextractor (SE) (Bertin e Arnouts, 1996). Este software também foi utilizado para classificá-los como galáxias ou estrelas. Foram identificadas 172 galáxias neste campo, que também foram detectadas no Data Release 7 do Sloan Digital Sky Survey (SDSS). Estas galáxias foram então usadas para obter uma calibração fotométrica das imagens, comparando as magnitudes instrumentais e do SDSS nas mesmas bandas. Após a calibração fotométrica, e através da comparação com imagens do CFHTLS obtidas em cores semelhantes, as galáxias foram classificadas como membros de cluster, foreground ou background, a partir de sua posição nos diagramas cor-cor e cor-magnitude. A reconstrução da massa do aglomerado através da análise de lentes gravitacionais foi realizada em duas etapas. Na primeira, foi utilizado o software IM2SHAPE, desenvolvido por Bridle et al. (1998), que modela os objetos, adicionando até três gaussianas, cada uma definida por seis parâmetros: as coordenadas do centro do objeto, x0 e y0, a elipticidade e, o ângulo de posição , o produto dos semi-eixos maior e menor ab, e a amplitude A. Inicialmente, o programa foi executado apenas para as estrelas do campo, com o objetivo de se obter uma estimativa da distribuição da PSF. A estimativa foi então utilizado como entrada para a análise das galáxias. Na segunda etapa, para estimar a massa do aglomerado foi utilizado o programa LENSENT, desenvolvido por Marshall et al. (2002), cujos parâmetros de entrada são a elipticidade das galáxias de fundo e seus erros. Na técnica de lentes gravitacionais fracas, a dependência radial da deformação das galáxias de fundo permite determinar o perfil de massa do aglomerado. Para estimar a massa, ajustamos um perfil de uma Esfera Isotérmica Singular (SIS, na sigla em inglês), e determinamos o valor da massa dentro de um raio de 3Mpc, 1.3 ± 0.6 x 10¹ Msol. O resultado é consistente com o obtido por Bohringer et al., 2005, 1.7 x 10¹ Msol, através da análise em raios-X. Comparando o mapa de distribuição de luminosidade e da emissão de raios-X concluímos que eles são muito semelhantes à distribuição superficial de massa, resultado que indica equilíbrio. / In this work we studied the galaxy cluster RXC J1504-0248, at z=0.215, from images in the bands r\', g\' and i\' obtained with Gemini South telescope. The photometric calibration was performed by comparison with field objects identified in the Sloan Digital Sky Survey (SDSS). From the analysis of color-color and color-magnitude diagrams, galaxies in the field were then divided into cluster members, background and foreground objects. We determined the PSF using the IM2SHAPE program \\cite{Bridle98}. These results enabled us to obtain the cluster projected mass distribution through a weak lensing analysis performed with the LENSENT program \\cite{Marshall02}. We also shown that the cluster luminosity distribution and the X-ray emission are consistent with the mass map. Using a SIS model, we estimated the mass of the cluster, obtaining 1.3 x 10¹ Msun, consistent with the mass obtained in a previous X-ray analysis, 1.7 x 10¹ Msun, by \\cite{Bohringer05}.