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Background. Low placental weight is associated with adverse perinatal outcomes. Adolescent pregnant women are associated with higher preterm labour, low birth weight and fetal growth restriction rates than adult pregnant women.Objective. To compare placental and newborn weights between groups of adolescent (≤19 years old) and adult mothers (20 - 28 years old).Methods. A prospective cross-sectional study was conducted with primiparous mothers who had their deliveries at ≥37 weeks’ gestation, and without maternal chronic disease or obstetrical intercurrence. Adolescents were divided into two groups (group A1, aged

Objective: The aim of this study was to pool data on the proportion and prognostic impact of sources of bleeding in patients requiring re-exploration after adult cardiac surgery. Design: Systematic review of the literature and meta-analysis. Setting: Multistitutional study. Measurements and Main Results: A literature review was performed to identify studies published since 1990 evaluating the outcome after reoperation for bleeding or tamponade after adult cardiac surgery. Eighteen studies including 5,1497 patients fulfilled the selection criteria. Reoperation for bleeding/tamponade was performed in 2,455 patients (4.6%; 95% confidence interval [CI] 3.9%–5.2%, I² 92%). These had a significantly higher risk of in-hospital/30-day mortality compared with patients not reoperated for bleeding (pooled rates: 9.3% v 2.3%; risk ratio 3.30; 95% CI 2.52–4.32; I² 47%; 8 studies; 25,463 patients). Surgical sites of bleeding were identified in 65.7% of cases (95% CI 58.3%–73.2%; I² 94%), cardiac site bleeding in 40.9% of cases (95% CI 29.7%–52.0%; I² 94%), and mediastinal/sternum site bleeding in 27.0% of cases (95% CI 16.8%–37.3%; I² 94%). The main sites of bleeding were the body of the graft (20.2%), the sternum (17.0%), vascular sutures (12.5%), the internal mammary artery harvest site (13.0%), and anastomoses (9.9%). In metaregression, surgical site bleeding was associated with a lower risk of in-hospital/30-day mortality compared with diffuse bleeding (p = 0.003). Conclusions: Surgical site bleeding is identified in two-thirds of patients undergoing re-exploration after adult cardiac surgery. Meticulous surgical technique and systematic intraoperative checking of potential surgical sites of bleeding at the time of the original cardiac surgery may reduce the risk of such a severe complication.

Background Severe hypoperfusion can cause lung damage. We studied the effects of regional perfusion block in normal lungs and in the lungs that had been conditioned by lavage with 500 ml saline and high V T (20 ml kg−1) ventilation. Methods Nineteen pigs (61.2 ± 2.5 kg) were randomized to five groups: controls (n = 3), the right lower lobe block alone (n = 3), lavage and high V T (n = 4), lung lavage, and high V T plus perfusion block of the right (n = 5) or left (n = 4) lower lobe. Gas exchange, respiratory mechanics, and hemodynamics were measured hourly. After an 8-h observation period, CT scans were obtained at 0 and 15 cmH2O airway pressure. Results Perfusion block did not damage healthy lungs. In conditioned lungs, the left perfusion block caused more edema in the contralateral lung (777 ± 62 g right lung vs 484 ± 204 g left; p

Tese de doutoramento em Engenharia Civil, Most important theoretical developments in finance and investment have been put to widespread practical use, especially in the more efficient securities markets. Real estate investment research has followed these developments, with a 20 year lag, but to some extent, common practice of asset allocation in a property portfolio still relies on qualitative and subjective personal judgment. In Portugal, academic research on property finance is, at least, incipient. The general objective of this research is the development of a compared analysis of the Portuguese real estate investment market in terms of its maturity and transparency, in order to evaluate the potential of attracting international investment and to provide with foundations for future development. Three fundamental issues are addressed: availability of quality information to develop consistent analysis to support managerial decisions, the existence and nature of institutional property investment and the sophistication degree of professional practices. The first specific objective is establishing a general characterization ofthe available information on return of the Portuguese and Iberian direct real estate market nature and also a more specific one in terms of its segmentation structure. There is an intuitive and generalized perception that investors should use a structured approach to portfolio management for the maximization of results, which should be heavily conditioned by the common definitions of market segments. This raises questions on the actual leveI of reflection of systematic factors that effectively condition returns by the segment structures used in the Portuguese market. Results show that the structures based on Sector differentiation are generally significant and that regional spread does not condition property returns in the periods under study. This evidence supports the argument of Sector diversification, both in the Portuguese market and even in an enlarged Iberian context, similarly to the reality found by in similar research for the UK market. The second objective is an analysis of the available Portuguese real estate indirect investment vehicles, the real estate investment fund (REIF) industry, concerning its return related information, mostly in terms of distribution features, analysis and predictability. This study develops a detailed characterization of the most important available data on REIF performance, covering sources, base sample, construction methods and also a detailed analysis on the time series data as a basis for future research on performance prediction and attribution models, evaluating consistency, autocorrelation and explanatory relationships between variables and endogenous and exogenous factors. Strong evidence of behavioural heterogeneity across the industry and its subsectors is found. As for return distributions, evidence of non-normality is rather overwhelming, in line with previous findings for other real estate markets. Finally, persistence analysis using contingency tables is developed, in order to further develop on the issue of predictability. Relevant and robust evidence of both short and long term performance persistence within the overall property fund industry and for the restricted universe of open¬ended funds was found. Lastly, the third objective is portraying the sophistication leveI of current practices and decision-making processes used by the Portuguese organizations managing real estate as a financial asset, emphasising on large portfolio holders. For this, a study based on a survey among a significant sample is developed. This includes REIF management societies, pension funds and large realty investment companies. The survey covers management decision-making practices, use of specific information, indices and databases, the role of appraisal, and the use of quantitative models to support diversification and asset allocation strategies, property selection decisions, performance measurement and benchmarking. The aim is to establish the real gap between theory, practical possibilities and real practice. Research design and results are presented and justified against economic reality, and recent similar studies in other markets., Os mais importantes desenvolvimentos teóricos em finanças foram postos em prática generalizadamente, em especial nos mais eficientes mercados de valores mobiliários. O investimento em imobiliário seguiu esta tendência com um desfasamento de 20 anos, mas em certa medida, a prática corrente de gestão de carteiras imobiliárias ainda se baseia em critérios qualitativos e empíricos. Em Portugal, a investigação académica nesta área é embrionária. O objectivo geral deste trabalho é o desenvolvimento de uma análise comparada do mercado Português de investimento imobiliário em termos da sua maturidade e transparência, de forma a avaliar o potencial de atracção de investimento internacional e bases para futuro desenvolvimento. Três tópicos fundamentais são abordados: a disponibilidade de informação de qualidade para desenvolvimento de análises consistentes que suportem decisões executivas, a existência de investimento institucional e o grau de sofisticação da prática profissional. O primeiro objectivo específico é a caracterização da natureza da informação disponível sobre a da rentabilidade dos mercados directos Português e Ibérico e uma análise mais específica das respectivas estruturas de segmentação. Existe uma percepção intuitiva e generalizada que os investidores devem utilizar uma estratégia estruturada na gestão de carteiras para maximizarem resultados, a qual deverá ser condicionada pelas estruturas comuns de segmentação do mercado. Isto levanta questões sobre o nível de incorporação nessas estruturas dos factores sistemáticos que efectivamente condicionam a rentabilidade. Os resultados obtidos mostram que as estruturas de segmentação baseadas no sector são em geral significativas, ao contrário das que usam a dispersão regional, para os períodos em estudo. Esta evidência suporta o argumento da diversificação por sector, tanto para o mercado Português como num contexto Ibérico, uma realidade semelhante à encontrada para o mercado do Reino Unido em trabalhos similares. O Segundo objectivo é a análise dos veículos indirectos de investimento imobiliário disponíveis no mercado, nomeadamente a indústria de fundos de investimento imobiliário (FII), no que concerne à informação sobre a sua rentabilidade, sobretudo em termos de características da respectiva distribuição de probabilidade, análise e previsão. Este estudo desenvolve uma caracterização detalhada da mais importante informação disponível sobre o desempenho de FII, incluindo as respectivas fontes, amostra, metodologias e ainda uma análise detalhada das séries temporais como potencial base de modelos de explicação e atribuição de desempenho, avaliando consistência, autocorrelação e relações de dependência com factores endógenos e exógenos. Foi encontrada forte evidência de heterogeneidade de comportamento das séries no âmbito da indústria e seus subsectores, e ainda de não-conformidade com os parâmetros de uma distribuição normal, o que está em linha com os resultados obtidos para outros mercados imobiliários. Finalmente, foi desenvolvida uma análise de persistência usando tabelas de contingência, no sentido de avaliar melhor a previsibilidade do seu desempenho. Os resultados mostraram de forma muito conclusiva evidência de persistência de desempenho, tanto de curto como de longo prazo, para o conjunto da indústria e no âmbito do segmento dos fundos abertos. Finalmente, o terceiro objectivo específico é o retrato do nível de sofisticação da prática profissional e processos de decisão usados por organizações Portuguesas que gerem activos imobiliários de investimento, sobretudo grandes carteiras. Para tal, foi desenvolvido um estudo baseado num inquérito a uma amostra significativa. Esta inclui sociedades gestoras de FII, fundos de pensões e grandes companhias de investimento imobiliário. Os temas abordados incluem os processos de decisão, o uso de modelos de suporte nas decisões de diversificação e escolha de propriedades, o papel da avaliação, e ainda medição e comparação de desempenho. O objectivo é o estabelecimento do desfasamento real entre a teoria, as possibilidades práticas e a realidade. A metodologia e os resultados são apresentados e justificados com base na realidade económica específica, e tendo em conta estudos similares noutros mercados.

Portuguese Real Estate Investment Funds are twenty years old and currently growing at unprecedented pace. Tax benefits and current market circumstances are the main drivers of interest on this type of institutional investment. In this paper a characterization and analysis of their nature, and a comparison against other indirect property investment vehicles is presented. Issues Iike structure, valuation, management, regulations and economical importance are addressed. A study of total return time series, covering trend analysis, descriptive statistics and return distributions, is developed. Evidence of the importance of endogenous factors in performance explanation and conclusiveverification of non-normality in return distributions are presented, pointing towards the need of further research on predictability issues.

Most important academic theoretical developments in finance and investment have been transferred to widespread practical use, especially in the more efficient securities markets. Real estate investment research has followed these developments, with a lag of about 20 years, but to some extent, common practice of asset allocation in a property portfolio still relies a lot on a qualitative and subjective personal judgment. To assess the reality and extent of this situation among the institutional property investors operating in the Portuguese market, a study based on a survey among a reference group of managers of large real estate portfolios was developed. This includes real estate fund management societies, pension funds and significant real property investment companies. The survey covers management decision-making practices, use of specific information, indices and databases, the role of appraisal, and the use of quantitative models regarding performance measurement, benchmarking and optimization of asset allocation. The aim is to establish the real gap between theory and practice. Research design is presented and justified against economic reality, and recent related and similar studies.