Improving drought tolerance in rainfed lowland rice: An example from Thailand

A large portion of the world's poor farm in rainfed systems where the water supply is unpredictable and droughts are common. In Thailand there are approximately 6.2 million ha of rain fed lowland rice, which account for 67% of the country's total rice-growing area. This rice system is often characterised by too much and too little water in the same season. Farmers' estimates of their annual losses to drought are as high as 45% in the upper parts of the toposequence. In contrast to irrigated rice systems, gains from crop improvement of rainfed rice have been modest, in part because there has been little effort to breed and select for drought tolerance for the target rainfed environments. The crop improvement strategy being used in Thailand considers three mechanisms that influence yield in the drought prone targets: yield potential as an important mechanism for mild drought (where yield loss is less than 50%), drought escape (appropriate phenology) and drought tolerance traits of leaf water potential, sterility, flower delay and drought response index for more severe drought conditions. Genotypes are exposed to managed drought environments for selection of drought tolerant genotypes. A marker assisted selection (MAS) scheme has been developed and applied for selection of progenies in the backcrossing program. The plant breeding program uses rapid generation advance techniques that enable early yield testing in the target population of environments (TPE) through inter-station (multi-location yield testing) and on-farm trials. A farmer participatory approach has been used to identify the TPE for the breeding program. Four terrace paddy levels have been identified, upper (drought), middle (drought prone to favorable) and lower (flooded). This paper reports the change in the breeding program for the drought prone tainted lowland rice environments of North and Northeast Thailand by incorporating our knowledge on adaptation and on response of rice to drought. (c) 2005 Elsevier B.V. All rights reserved.

Improving drought tolerance in rainfed lowland rice: an example from Thailand

A large portion of the world’s poor farm in rainfed systems where the water supply is unpredictable and droughts are common. In Thailand there are approximately 6.2 million ha of rain fed lowland rice which account for 67% of the country’s total rice-growing area. This rice system is often characterised by too much and too little water in the same season. Farmers’ estimates of their annual losses to drought are as high as 45% in the upper parts of the toposequence. In contrast to irrigated rice systems, gains from crop improvement of rainfed rice have been modest, in part because there has been little effort to breed and select for drought tolerance for the target rainfed environments. The crop improvement strategy being used in Thailand considers three mechanisms that influence yield in the drought prone targets: yield potential as an important mechanism for mild drought (where yield loss is less than 50%), drought escape (appropriate phenology) and drought tolerance traits of leaf water potential, sterility, flower delay and drought response index for more severe drought conditions. Genotypes are exposed to managed drought environments for selection of drought tolerant genotypes. A marker assisted selection (MAS) scheme has been developed and applied for selection of progenies in the backcrossing program. The plant breeding program uses rapid generation advance techniques that enable early yield testing in the target population of environments (TPE) through inter-station (multi-location yield testing) and on-farm trials. A farmer participatory approach has been used to identify the TPE for the breeding program. Four terrace paddy levels have been identified, upper (drought), middle (drought prone to favorable) and lower (flooded). This paper reports the change in the breeding program for the drought prone rainfed lowland rice environments of North and Northeast Thailand by incorporating our knowledge on adaptation and on response of rice to drought.

Institutions and firm ownership structure:evidence from Central and Eastern Europe

FDI plays a key role in development, particularly in resource-constrained transition economies of Central and Eastern Europe with relatively low savings rates. Gains from technology transfer play a critical role in motivating FDI, yet potential for it may be hampered by a large technology gap between the source and host country. While the extent of this gap has traditionally been attributed to education, skills and capital intensity, recent literature has also emphasized the possible role of institutional environment in this respect. Despite tremendous interest among policy-makers and academics to understand the factors attracting FDI (Bevan and Estrin, 2000; Globerman and Shapiro, 2003) our knowledge about the effects of institutions on the location choice and ownership structure of foreign firms remains limited. This paper attempts to fill this gap in the literature by examining the link between institutions and foreign ownership structures. To the best of our knowledge, Javorcik (2004) is the only papers, which use firm-level data to analyse the role of institutional quality on an outward investor’s entry mode in transition countries. Our paper extends Javorcik (2004) in a number of ways: (a) rather than a cross-section, we use panel data for the period 1997-2006; (b) rather than a binary variable, we use the percentage foreign ownership as continuous variable; (c) we consider multi-dimensional institutional variables, such as corruption, intellectual property rights protection and government stability. We also use factor analysis to generate a composite index of institutional quality and see how stronger institutional environment could affect foreign ownership; (d) we explore how the distance between institutional environment in source and host countries affect foreign ownership in a host country. The firm-level data used includes both domestic and foreign firms for the period 1997-2006 and is drawn from ORBIS, a commercially available dataset provided by Bureau van Dijk. In order to examine the link between institutions and foreign ownership structures, we estimate four log-linear ownership equations/specifications augmented by institutional and other control variables. We find evidence that the decision of a foreign firm to either locate its subsidiary or acquire an existing domestic firm depends not only on factor cost differences but also on differences in institutional environment between the host and source countries.

Comparison between detailed model simulation and artificial neural network for forecasting building energy consumption

There are several ways to attempt to model a building and its heat gains from external sources as well as internal ones in order to evaluate a proper operation, audit retrofit actions, and forecast energy consumption. Different techniques, varying from simple regression to models that are based on physical principles, can be used for simulation. A frequent hypothesis for all these models is that the input variables should be based on realistic data when they are available, otherwise the evaluation of energy consumption might be highly under or over estimated. In this paper, a comparison is made between a simple model based on artificial neural network (ANN) and a model that is based on physical principles (EnergyPlus) as an auditing and predicting tool in order to forecast building energy consumption. The Administration Building of the University of Sao Paulo is used as a case study. The building energy consumption profiles are collected as well as the campus meteorological data. Results show that both models are suitable for energy consumption forecast. Additionally, a parametric analysis is carried out for the considered building on EnergyPlus in order to evaluate the influence of several parameters such as the building profile occupation and weather data on such forecasting. (C) 2008 Elsevier B.V. All rights reserved.

Evaluation of Characterization and Performance Modeling of Cementitiously Stabilized Layers in the Mechanistic-Empirical Pavement Design Guide

Cementitious stabilization of aggregates and soils is an effective technique to increase the stiffness of base and subbase layers. Furthermore, cementitious bases can improve the fatigue behavior of asphalt surface layers and subgrade rutting over the short and long term. However, it can lead to additional distresses such as shrinkage and fatigue in the stabilized layers. Extensive research has tested these materials experimentally and characterized them; however, very little of this research attempts to correlate the mechanical properties of the stabilized layers with their performance. The Mechanistic Empirical Pavement Design Guide (MEPDG) provides a promising theoretical framework for the modeling of pavements containing cementitiously stabilized materials (CSMs). However, significant improvements are needed to bring the modeling of semirigid pavements in MEPDG to the same level as that of flexible and rigid pavements. Furthermore, the MEPDG does not model CSMs in a manner similar to those for hot-mix asphalt or portland cement concrete materials. As a result, performance gains from stabilized layers are difficult to assess using the MEPDG. The current characterization of CSMs was evaluated and issues with CSM modeling and characterization in the MEPDG were discussed. Addressing these issues will help designers quantify the benefits of stabilization for pavement service life.

Adolescent depressive symptomatology: Improve schools or help students?

Despite the increasing interest in programs designed to improve the social ecology of schools, surprisingly little is known about whether differences between schools influence student mental health. This 3-year prospective, naturalistic study examines the school effect on adolescent depressive symptomatology (measured by the Center for Epidemiological Studies Depression Scale, CES-D) among 2,489 students from 25 Australian high schools. Multilevel modelling techniques (HLM) formed the basis of the statistical analyses, There were statistically significant school effects on students' depressive symptomatology; however, these were much smaller than expected. Nearly all of the variation in CES-D depression scores was found to be at the student level, indicating that the potential mental health gains from reducing risk factors in school social environments may be extremely limited and have little effect on student depressive symptomatology.

Productivity growth in Australian manufacturing sector: some new evidence

This article examines the productivity performance of Australia's manufacturing sector by decomposing its output growth into input growth, technological progress and gains in technical efficiency. This three-way decomposition is done with an improved version of the stochastic frontier model using eight, two-digit industry level data from 1968/9 to 1994/5. Empirical evidence shows that input growth fueled output growth from 1968/9 to 1973/4, but since then, total factor productivity (TFP) growth has been the main contributor of output growth. While the trend of TFP growth was found to be promising for most industries with positive and increasing technological progress, the negative gains from technical efficiency over time is however cause for concern.

Benefits, harms and costs of screening mammography in women 70 years and over: a systematic review

Objective: To assess the (i) benefits, (ii) harms and (iii) costs of continuing mammographic screening for women 70 years and over. Data sources and synthesis: (i) We conducted a MEDLINE search (1966 - July 2000) for decision-analytic models estimating life-expectancy gains from screening in older women. The five studies meeting the inclusion criteria were critically appraised using standard criteria. We estimated relative benefit from each model's estimate of effectiveness of screening in older women relative to that in women aged 50-69 years using the same model. (ii) With data from BreastScreen Queensland, we constructed balance sheets of the consequences of screening for women in 10-year age groups (40-49 to 80-89 years), and (iii) we used a validated model to estimate the marginal cost-effectiveness of extending screening to women 70 years and over. Results: For women aged 70-79 years, the relative benefit was estimated as 40%-72%, and 18%-62% with adjustment for the impact of screening on quality of life. For women over 80 years the relative benefit was about a third, and with quality-of-life adjustment only 14%, that in women aged 50-69 years. (ii) Of 10 000 Australian women participating in ongoing screening, about 400 are recalled for further testing, and, depending on age, about 70-112 undergo biopsy and about 19-80 cancers are detected. (iii) Cost-effectiveness estimates for extending the upper age limit for mammographic screening from 69 to 79 years range from $8119 to $27 751 per quality-adjusted life-year saved, which compares favourably with extending screening to women aged 40-49 years (estimated at between $24 000 and $65 000 per life-year saved). Conclusions: Women 70 years and over, in consultation with their healthcare providers, may want to decide for themselves whether to continue mammographic screening. Decision-support materials are needed for women in this age group.

Variabilidade genética em famílias de meios-irmãos de cafeeiro robusta

O cultivo do café é uma das atividades do agronegócio de maior importância socioeconômica dentre as diferentes atividades ligadas ao comércio agrícola mundial. Uma das maiores contribuições da genética quantitativa para o melhoramento genético é a possibilidade de prever ganhos genéticos. Quando diferentes critérios de seleção são considerados, a predição de ganhos referentes a cada critério tem grande importância, pois indica os melhoristas sobre como utilizar o material genético disponível, visando obter o máximo de ganhos possível para as características de interesse. O presente trabalho foi instalado em julho de 2004, na Fazenda Experimental de Bananal do Norte, conduzida pelo Incaper, no distrito de Pacotuba, município de Cachoeiro de Itapemirim, região Sul do Estado, com o objetivo de selecionar as melhores plantas entre e dentro de progênies de meios- irmãos de Coffea canephora, por meio de diferentes critérios de seleção. Foram realizadas análises de variância individuais e conjuntas para 26 progênies de meios- irmãos Coffea canephora. O delineamento experimental utilizado foi em blocos ao acaso com quatro testemunhas adicionais com quatro repetições e parcela composta por cinco plantas, com o espaçamento de 3,0 m x 1,2 m. Neste trabalho, considerou-se os dados das últimas cinco colheitas. As características mensuradas foram: florescimento, maturação, tamanho do grão, peso, porte, vigor, ferrugem, mancha cercóspora, seca de ponteiros, escala geral, porcentagem de frutos boia e bicho mineiro. Todas as análises estatísticas foram realizadas com o aplicativo computacional em genética e estatística (GENES). Foram estimados os ganhos de seleção em função da porcentagem de seleção de 20% entre e dentro, sendo as mesmas mantidas para todas as características. Todas as características foram submetidas a seleção no sentido positivo, exceto para florescimento, porte, ferrugem, mancha cercóspora, seca de ponteiros, porcentagem de frutos boia e bicho mineiro, para obter decréscimo em suas médias originais. Os critérios de seleção estudados foram: seleção convencional entre e dentro das famílias, índice de seleção combinada, seleção massal e seleção massal estratificada. Esta dissertação é composta por dois capítulos, em que foram realizadas análises biométricas, como a obtenção de estimativas de parâmetros genéticos. Na maioria das características estudadas, verificaram-se diferenças significativas (P<0,05) para genótipos que, associados aos coeficientes de variação genotípicos e também ao coeficiente de determinação genotípico e à relação CVg/CVe, indicam a existência de variabilidade genética nos materiais genéticos para a maioria das características e condições favoráveis para obtenção de ganhos genéticos pela seleção. Essas características também foram correlacionadas. Os dados foram submetidos às análises de variância e multivariada, aplicando-se a técnica de agrupamento e UPGMA, teste de médias e estudo de correlações. Na técnica de agrupamento, foi utilizada a distância generalizada de Mahalanobis como medida de dissimilaridade, e na delimitação dos grupos, o método de Tocher. Foi encontrada diversidade genética para as características associadas à qualidade fisiológica, mobilização de reserva das sementes, dimensões e biomassa das plântulas. Quatro grupos de genótipos puderam ser formados. Peso de massa seca de sementes, redução de reserva de sementes e peso de massa seca de plântulas estão positivamente correlacionados entre si, enquanto a redução de reserva das sementes e a eficiência na conversão dessas reservas em plântulas estão negativamente correlacionadas. De acordo com os resultados obtidos, verificou-se que todas as características apresentaram níveis diferenciados de variabilidade genética e os critérios de seleção utilizados mostraram-se eficientes para o melhoramento, no qual o índice de seleção combinada é o critério de seleção que apresentou os melhores resultados em termos de ganhos, sendo indicado como critério mais apropriado para o melhoramento genético da população estudada. Nos estudos de correlações, em 70% dos casos, a correlação fenotípica foi superior à genotípica, mostrando maior influência dos fatores ambientais em relação aos genotípicos e condições propícias ao melhoramento dos diferentes caracteres. No estudo de divergência genética, observou-se que pelo agrupamento de genótipos, pela técnica de Tocher, indicou que os genótipos foram distribuídos em três grupos.

A influência da marca Nespresso no comportamento de compra da máquina e cápsulas de café

Dissertação apresentada à Escola Superior de Comunicação Social como parte dos requisitos para obtenção de grau de mestre em Publicidade e Marketing.

Economias de escala em centros hospitalares

RESUMO - Perante o actual contexto de contenção de gastos no sector da saúde e consequente preocupação com a eficiência do sistema, tem‐se assistido a mudanças várias no modelo de gestão e organizacional do sistema de saúde. Destaca‐se a alteração da estrutura hospitalar, com vista à racionalização dos seus recursos internos, onde as fusões hospitalares têm assumido um papel determinante. Em Portugal, nos últimos 10 anos, assistiu‐se a uma significativa redução do número de hospitais (de sensivelmente 90 para 50 unidades), exclusivamente através das fusões e sem quaisquer alterações no número de estruturas físicas existentes. Não obstante os argumentos justificativos desta reforma, a avaliação dos objectivos implícitos é insuficiente. Neste âmbito, pretendeu‐se com este estudo contribuir para a análise do impacte da criação de centros hospitalares na redução de gastos, isto é, verificar se a consolidação e consequente reengenharia dos processos produtivos teve consequencias ao nível da obtenção de economias de escala. Para esta análise usou‐se uma base de dados em painel, onde se consideraram 75 hospitais durante 7 anos (2003‐2009), número que foi reduzindo ao longo do período em análise devido às inúmeras fusões já referidas. Para avaliar os ganhos relativos às fusões hospitalares, ao nível da eficiência técnica e das economias de escala, recorreu‐se à fronteira estocástica especificada função custo translog. Estimada a fronteira, foi possível analisar três centros hospitalares específicos, onde se comparou o período pré‐fusão (2005‐2006) com o período após a fusão (2008‐2009). Como variáveis explicativas, relativas à produção hospitalar, considerou‐se o número de casos tratados e os dias de internamento (Vita, 1990; Schuffham et al., 1996), o número de consultas e o número de urgências, sendo estas variáveis as mais comuns na literatura (Vita, 1990; Fournier e Mitchell, 1992; Carreira, 1999). Quanto à variável dependente usou‐se o custo variável total, que compreende o total de custos anuais dos hospitais excepto de imobilizado. Como principais conclusões da investigação, em consequência da criação dos centros hospitalares, são de referir os ganhos de escala na fusão de hospitais de reduzida dimensão e com mais serviços complementares. --------ABSTRACT - Driven by the current pressure on resources induced by budgetary cuts, the Portuguese Ministry of Health is imposing changes in the management model and organization of NHS hospitals. The most recent change is based on the creation of Hospital Centres that are a result of administrative mergers of existing hospitals. In less than 10 years the number of hospitals passed from around 90 to around 50, only due to the mergers and without any change in the existing number of physical institutions. According to the political discourse, one of the main goals expected from this measure is the creation of synergies and more efficiency in the use of available resources. However, the merger of the hospitals has been a political decision without support or evaluation of the first experiments. The aim of this study is to measure the results of this policy by looking at economies of scale namely through reductions in the expenditures, as expected and sought by the MoH. Data used covers 7 years (2003‐2009) and 75 hospitals, number that has been reduced my the enoumerous mergers during the last decade. This work uses a stochastic frontier analysis through the translog cost function to examine the gains from mergers, which were decomposed into technical efficiency and economies of scale. It was analised these effects by the creation of three specific hospital centers, using a longitudinal approach to compare the period pre‐merger (2003‐2006) with the post‐merger period (2007‐09). To measure changes in inpatient hospital production volume and length of stay are going to be considered as done by Vita (1990) and Schuffham et al. (1996). For outpatient services the number of consultations and emergencies are going to be considered (Vita, 1990; Fournier e Mitchell, 1992; Carreira, 1999). Total variable cost is considered as the dependent variable explained the aforementioned ones. After a review of the literature results expected point to benefits from the mergers, namely a reduction in total expenditures and in the number of duplicated services. Results extracted from our data point in the same direction, and thus for the existence of some economies of scale only for small hospitals.

The optimum size of the portuguese public hospital

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics

The use of technology in Portuguese hospitals: The case of MRI

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics

The value relevance of tangible fixed assets

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Finance from the NOVA – School of Business and Economics

Thermal performance of cool facades: evaluation by Infrared Thermography

High reflective paints (cool paints) are used on flat roofs to reduce heat gains from the incidence of solar radiation and thus improve the thermal comfort and energy efficiency of buildings, especially in summer periods. Given the application potential of these paints on vertical surfaces, a research study has been developed to evaluate the thermal performance of reflective paints on walls under real exposure conditions. Accordingly, different reflective paints have been applied as the final coating of an ETICS type solution, on the facades of a full scale experimental cell built at LNEC campus. For being applied in an ETICS system a paint has to fulfill several requirements, whether aesthetic or functional (such as the adhesion between the coating layers or the durability of the insulation), essential for its efficient performance. Since this construction coating system is subject to a prolonged sun exposure, various problems may arise, such as paint degradation or deterioration of the thermal insulation properties, particularly when dark colors are applied. To evaluate the thermal performance of the chosen paints, the method of non-destructive analysis by Infrared Thermography was used. Thermography allows knowing the temperature distribution of facades by measuring the radiation emitted by their surfaces. To complement the thermographic diagnosis, thermocouples were placed between the insulation and the paint system of the experimental cell. Additional laboratory tests allowed the characterization of the optical properties (reflectance and emittance) of the different reflective paints used in this study. The comparative analysis of the thermal performance of reflective and conventional paints revealed that the reflective paint allows a reduction of the facade surface temperature, reducing the risk of loss of insulating properties of the ETICS system and thus ensuring its longevity and functionality. The color of the paint used affects, naturally, the reflective ability of the surface and may have an important role in energy balance of the building. This paper also showed the potential of infrared thermography in the evaluation of the thermal performance of reflective paints.