Within this thesis, we present an extended multiwavelength analysis of the rich massive Galactic star-forming complex G305. We have focused our attention on studying the both the embedded massive star-forming population within G305, while also identifying the intermediate-, to lowmass content of the region also. Though massive stars play an important role in the shaping and evolution of their host galaxies, the physics of their formation still remains unclear. We have therefore set out to studying the nature of star formation within this complex, and also identify the impact that such a population has on the evolution of G305. We firstly present a Herschel far-infrared study towards G305, utilising PACS 70, 160 μm and SPIRE 250, 350, and 500 μm observations from the Hi-GAL survey of the Galactic plane. The focus of this study is to identify the embedded massive star-forming population within G305, by combining far-infrared data with radio continuum, H2O maser, methanolmaser,MIPS, and Red MSX Source survey data available from previous studies. From this sample we identify some 16 candidate associations are identified as embedded massive star-forming regions, and derive a two-selection colour criterion from this sample of log(F70/F500)! 1 and log(F160/F350)! 1.6 to identify an additional 31 embedded massive star candidates with no associated starformation tracers. Using this result, we are able to derive a star formation rate (SFR) of 0.01 - 0.02 M! yr−1. Comparing this resolved star formation rate, to extragalactic star formation rate tracers (based on the Kennicutt-Schmidt relation), we find the star formation activity is underestimated by a factor of !2 in comparison to the SFR derived from the YSO population. By next combining data available from 2MASS and VVV, Spitzer GLIMPSE and MIPSGAL, MSX, and Herschel Hi-GAL, we are able to identify the low-, to intermediate-mass YSOs present within the complex. Employing a series of stringent colour selection criteria and fitting reddened stellar atmosphere models, we are able remove a significant amount of contaminating sources from our sample, leaving us with a highly reliable sample of some 599 candidate YSOs. From this sample, we derive a present-day SFR of 0.005±0.001M! yr−1, and find the YSOmass function (YMF) of G305 to be significantly steeper than the standard Salpeter-Kroupa IMF. We find evidence of mass segregation towards G305, with a significant variation of the YMF both with the active star-forming region, and the outer region. The spatial distribution, and age gradient, of our 601 candidate YSOs also seem to rule out the scenario of propagating star formation within G305, with a more likely scenario of punctuated star formation over the lifetime of the complex.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Entrepreneurship is considered an important vehicle for economic performance, creating and fostering the original factors of production, capital and labor. This work has as main theme entrepreneurial activity and its relationship to employment. For this, the general objective is to investigate the behavior of entrepreneurship and its relation to the variation in employment rates in Brazil and in the five regions of the country. The variables used in the study were the rate of formation of companies - TFE and Change in employment - VEMP, and the period was 2007-2010. The statistical techniques used as a methodology of analysis were descriptive statistics, Spearman correlation coefficient and Friedman analysis of variance - ANOVA. Observed through the analysis, distinct behaviors during 2007-2010 among the five regions, revealing a heterogeneous format of business activity and employment in the country. The most relevant results of this study indicate the existence of positive and moderate correlation between variables, in Brazil, in the years 2008 and 2010. In the regional analysis found a significant correlation, though negative, between the variables in the North in the years 2007 and 2009, suggesting the inverse relationship between variables in this period. It concludes with the work that traditionally poor regions showed better results in the formation of companies for regions with better socio-economic indicators. Moreover, there was the need for public policies aimed at business activity already consolidated. / O empreendedorismo é considerado um veículo importante para o bom desempenho econômico, gerando e dinamizando os fatores de produção originais, capital e trabalho. Este trabalho apresenta como tema principal a atividade empreendedora e sua relação com o emprego. Para isso, o objetivo geral é investigar o comportamento do empreendedorismo e sua relação com a variação nas taxas de emprego no Brasil e nas cinco regiões do país. As variáveis utilizadas no trabalho foram a Taxa de formação de empresas TFE e a Variação no emprego VEMP, e o período analisado foi 2007-2010. As técnicas estatísticas utilizadas como metodologia de análise foram a estatística descritiva, Coeficiente de correlação de Spearman e Análise de variância de Friedman ANOVA. Observaram-se por meio da análise, comportamentos distintos no período 2007-2010 entre as cinco regiões, revelando um formato heterogêneo da atividade empresarial e do emprego no país. Os resultados mais relevantes deste estudo apontam a existência de correlação positiva e moderada entre as variáveis, no Brasil, nos anos 2008 e 2010. Na análise regional foi encontrada correlação significativa, porém negativa, entre as variáveis na região Norte nos anos 2007 e 2009, o que sugere a relação inversa entre as variáveis neste período. Conclui-se com o trabalho que regiões tradicionalmente pobres apresentaram melhores resultados na formação de empresas em relação às regiões com melhores indicadores sócio-econômicos. Além disso, observou-se a necessidade de políticas públicas voltadas para a atividade empresarial já consolidada.

<p>Ultra/Luminous infrared galaxies (U/LIRGs) are some of the most amazing systems in the local universe exhibiting extreme star formation triggered by mergers. Since molecular gas is the fuel for star formation, studying the warm, dense gas associated with star formation is important in understanding the processes and timescales controlling star formation in mergers. We have used high resolution (∼2.3”) observations of the local LIRG Arp 299 to map out the physical properties of the molecular gas. The molecular lines 12CO J=3-2, 12CO J=2-1 and 13CO J=2-1 were observed with the Submillimeter Array and the short spacings of the 12CO J=3-2 and J=2-1 observations have been recovered using James Clerk Maxwell Telescope single dish observations. We use the radiative transfer code RADEX to measure the physical properties such as density and temperature of the different regions in this system. The RADEX solutions of the two galaxy nuclei, IC 694 and NGC 3690, show two gas components: a warm moderately dense gas with T_kin ∼ 30-500 K (up to 1000K for NGC3690) and n(H2)~0.3-3×10^3 cm^−3 and a cold dense gas with T_kin~10-30 K and n(H2) > 3 × 10^3 cm^−3. The overlap region is shown to have a well-constrained solution with T_kin ∼ 10-30 K and n(H2)~3-30 × 10^3 cm^−3. We estimate the gas masses and star formation rates of each region in order to derive molecular gas depletion times. The depletion time of each region is found to be about 2 orders of magnitude lower than that of normal spiral galaxies. This can be probably explained by a higher fraction of dense gas in Arp 299 than in normal disk galaxies.</p> / Master of Science (MSc)