A framework for agricultural adaptation to climate change in Southern Nigeria

The agricultural sector which contributes between 20-50% of gross domestic product in Africa and employs about 60% of the population is greatly affected by climate change impacts. Agricultural productivity and food prices are expected to rise due to this impact thereby worsening the food insecurity and poor nutritional health conditions in the continent. Incidentally, the capacity in the continent to adapt is very low. Addressing these challenges will therefore require a holistic and integrated adaptation framework hence this study. A total of 360 respondents selected through a multi-stage random sampling technique participated in the study that took place in Southern Nigeria from 2008-2011. Results showed that majority of respondents (84%) were aware that some climate change characteristics such as uncertainties at the onset of farming season, extreme weather events including flooding and droughts, pests, diseases, weed infestation, and land degradation have all been on the increase. The most significant effects of climate change that manifested in the area were declining soil fertility and weed infestation. Some of the adaptation strategies adopted by farmers include increased weeding, changing the timing of farm operations, and processing of crops to reduce post-harvest losses. Although majority of respondents were aware of government policies aimed at protecting the environment, most of them agreed that these policies were not being effectively implemented. A mutually inclusive framework comprising of both indigenous and modern techniques, processes, practices and technologies was then developed from the study in order to guide farmers in adapting to climate change effects/impacts.

A conceptual framework for aligning business and information systems from organisational learning perspective

The three decades of on-going executives’ concerns of how to achieve successful alignment between business and information technology shows the complexity of such a vital process. Most of the challenges of alignment are related to knowledge and organisational change and several researchers have introduced a number of mechanisms to address some of these challenges. However, these mechanisms pay less attention to multi-level effects, which results in a limited un-derstanding of alignment across levels. Therefore, we reviewed these challenges from a multi-level learning perspective and found that business and IT alignment is related to the balance of exploitation and exploration strategies with the intellec-tual content of individual, group and organisational levels.

Automating the product derivation process of multi-agent systems product lines

Agent-oriented software engineering and software product lines are two promising software engineering techniques. Recent research work has been exploring their integration, namely multi-agent systems product lines (MAS-PLs), to promote reuse and variability management in the context of complex software systems. However, current product derivation approaches do not provide specific mechanisms to deal with MAS-PLs. This is essential because they typically encompass several concerns (e.g., trust, coordination, transaction, state persistence) that are constructed on the basis of heterogeneous technologies (e.g., object-oriented frameworks and platforms). In this paper, we propose the use of multi-level models to support the configuration knowledge specification and automatic product derivation of MAS-PLs. Our approach provides an agent-specific architecture model that uses abstractions and instantiation rules that are relevant to this application domain. In order to evaluate the feasibility and effectiveness of the proposed approach, we have implemented it as an extension of an existing product derivation tool, called GenArch. The approach has also been evaluated through the automatic instantiation of two MAS-PLs, demonstrating its potential and benefits to product derivation and configuration knowledge specification.

Performance-based compensation vs. guaranteed compensation: contractual incentives and performance

Top management from retail banks must delegate authority to lower-level managers to operate branches and service centers. Doing so, they must navigate through conflicts of interest, asymmetric information and limited monitoring in designing compensation plans for such agents. Pursuant to this delegation, the banks adopt a system of performance targets and incentives to align the interests of senior management and unit managers. This paper evaluates the causal relationship between performance-based salaries and managers’ effective performance. We use a fixed effects estimator to analyze an unbalanced panel of data from one of the largest Brazilian retail banks during the period from January 2007 to June 2009. The results indicate that agents with guaranteed variable salary contracts demonstrate inferior performance compared with agents who have performance-based compensation packages. We conclude that there is a moral hazard that can be observed in the behavior of agents who are subject to guaranteed variable salary contracts.

Impactos da política fiscal e tributária no crescimento econômico

Utilizando uma adaptação do modelo de Telles e Mussolini (2014), o presente trabalho busca discutir as caracterizações da matriz tributária, discutindo como as variações na matriz tributária podem impactar na política fiscal. Discute-se com base na diferenciação dos impostos em cinco grupos, a saber: impostos sobre salários, impostos sobre investimentos, impostos sobre consumo, impostos sobre renda e riqueza, e impostos sobre comércio internacional, a partir dos quais argumenta-se quais seus impactos para a política fiscal, para a interação das variáveis econômicas e a evolução destas variáveis, assim como a relação entre a preferência por uma determinada estrutura tributária e o endividamento de um país. Após a discussão teórica, faz-se uma análise descritiva da evolução destas variáveis tributárias para cada categoria de tributo, relacionando a sua evolução no tempo para um grupo de 64 países, tomados a partir do trabalho de Telles e Mussolini (2014), assim como relacionando a sua evolução intertemporal. Por fim, faz-se uma análise da estrutura tributária destes países, discutindo, na análise dos dados em painel, os resultados para as estimativas em modelos de efeitos fixos e efeitos aleatórios, os resultados da estimação pelo modelo Arellano-Bond, e utilizando-se a abordagem instrumental pelo Método Generalizado dos Momentos, onde se conclui que a taxação sobre a riqueza e a taxação sobre o comércio internacional com fins de financiar o excesso de gastos do governo impacta de forma negativa na trajetória de crescimento, entre outros resultados.

Impactos da imigração no mercado de trabalho brasileiro

Diante da importância que o tema da imigração adquiriu no país nos últimos anos, gerou-se uma necessidade de melhor entendimento dos efeitos econômicos causados por influxos populacionais dessa natureza. Todavia, sob o conhecimento dos autores, inexistem estudos para história recente brasileira acerca dos impactos dos imigrantes no mercado de trabalho, em especial, sobre o salário e o nível de emprego dos nativos. Com esse panorama em mente, os estudos realizados nesta tese visam dar os primeiros passos na investigação desse tema. O presente trabalho é composto por quatro capítulos, os quais examinam diferentes questões associadas aos efeitos da imigração no mercado de trabalho brasileiro. O primeiro capítulo motiva o tema da imigração no Brasil e, através de uma metodologia estrutural baseada no arcabouço da função CES multi-nível, simula o efeito na estrutura salarial em resposta a influxos imigratórios estipulados para o ano de 2010, data do último Censo Demográfico. Em particular, calcula-se que o impacto salarial médio decorrente de um influxo estipulado de 549 mil imigrantes, mesma magnitude do observado entre dezembro de 2010 e dezembro de 2011, estaria situado em torno de -0.25%. O segundo capítulo estima o grau de substituição entre imigrantes e nativos do mesmo grupo de habilidade e testa a hipótese de substituição perfeita suportada empiricamente por Borjas et al. (2012, 2008) e adotada no capítulo anterior. A metodologia empregada fundamenta-se no arcabouço estrutural desenvolvido em Manacorda et al. (2012) e Ottaviano & Peri (2012), o qual acrescenta um nível extra na função de produção CES multi-nível de Borjas (2003). As elasticidades de substituição estimadas sob diversas especificações variam entre 9 e 23, resultados que fortalecem a tese de substituição imperfeita preconizada por Card (2012). O terceiro capítulo estima dois tipos de elasticidades relacionadas ao impacto dos imigrantes sobre o rendimento do trabalho nativo através de uma metodologia alternativa baseada numa função de produção mais flexível e que não está sujeita a restrições tão austeras quanto a CES. As estimativas computadas para as elasticidades de substituição de Hicks subjacentes se situam entre 1.3 e 4.9, o que reforça as evidências de substituição imperfeita obtidas no Capítulo 2. Adicionalmente, os valores estimados para as elasticidades brutas dos salários dos nativos em relação às quantidades de imigrantes na produção são da ordem máxima de +-0.01. O quarto e último capítulo, por meio de uma metodologia fundamentada no arcabouço da função de custo Translog, examina como o nível de emprego dos nativos reage a alterações no custo do trabalho imigrante, uma questão que até o momento recebeu pouca atenção da literatura, conquanto apresente relevância para formulação de políticas imigratórias. Para todas as especificações de modelo e grupos de educação considerados, nossos resultados apontam que uma variação exógena no salário do imigrante produz apenas diminutos efeitos sobre o nível de emprego dos trabalhadores nativos brasileiros. Na maioria dos casos, não se pode rejeitar a hipótese de que nativo e imigrante não são nem p-complementares nem p-substitutos líquidos.

Undersampled Critical Branching Processes on Small-World and Random Networks Fail to Reproduce the Statistics of Spike Avalanches

The power-law size distributions obtained experimentally for neuronal avalanches are an important evidence of criticality in the brain. This evidence is supported by the fact that a critical branching process exhibits the same exponent t~3=2. Models at criticality have been employed to mimic avalanche propagation and explain the statistics observed experimentally. However, a crucial aspect of neuronal recordings has been almost completely neglected in the models: undersampling. While in a typical multielectrode array hundreds of neurons are recorded, in the same area of neuronal tissue tens of thousands of neurons can be found. Here we investigate the consequences of undersampling in models with three different topologies (two-dimensional, small-world and random network) and three different dynamical regimes (subcritical, critical and supercritical). We found that undersampling modifies avalanche size distributions, extinguishing the power laws observed in critical systems. Distributions from subcritical systems are also modified, but the shape of the undersampled distributions is more similar to that of a fully sampled system. Undersampled supercritical systems can recover the general characteristics of the fully sampled version, provided that enough neurons are measured. Undersampling in two-dimensional and small-world networks leads to similar effects, while the random network is insensitive to sampling density due to the lack of a well-defined neighborhood. We conjecture that neuronal avalanches recorded from local field potentials avoid undersampling effects due to the nature of this signal, but the same does not hold for spike avalanches. We conclude that undersampled branching-process-like models in these topologies fail to reproduce the statistics of spike avalanches.

Análise de fatores genéticos e ambientais que afetam a infestação de fêmeas bovinas da raça Caracu por carrapatos (Boophilus microplus)

Este trabalho foi conduzido com o objetivo de avaliar o efeito de fatores de meio sobre a infestação de bovinos Caracu pelo carrapato Boophilus microplus (Canestrini, 1887) e estimar parâmetros genéticos do grau de infestação por esse ectoparasita. Foram realizadas contagens em fêmeas de dois rebanhos, nas quatro estações, por dois anos consecutivos (setembro/1998 a julho/2000). Contou-se o número de carrapatos (NC) em um dos lados do animal e atribuiu-se escore visual (EC) de acordo com a quantidade de carrapatos no animal. Foram feitas de uma a oito avaliações, totalizando-se 4.079 e 3.994 observações de NC e EC, respectivamente, em 718 animais. Os dados foram analisados pelo método dos quadrados mínimos com um modelo que incluiu efeitos de rebanho (R), cor do animal (C), R x C, animal dentro de R x C como erro a, ano e estação da avaliação, espessura de pelame e idade do animal como covariável. As estimativas dos componentes de variância foram obtidas pelo método da máxima verossimilhança restrita livre de derivadas, utilizando-se um modelo que incluiu os efeitos fixos de grupo de contemporâneos (fazenda-ano-época), espessura do pelame e idade do animal como covariável e os efeitos aleatórios aditivos diretos e de ambiente permanente. Antes das análises, a variável NC foi transformada para log10 (n + 1) e EC para (x + 0,5)½, em que n é o número de carrapatos contados no animal e x, o escore (0 a 4). A incidência de carrapatos foi maior no verão e, quanto maior a espessura do pelame, maior o nível de infestação. As estimativas de herdabilidade e repetibilidade foram, respectivamente, 0,22 e 0,29 para NC e 0,15 e 0,21 para EC; a correlação genética entre NC e EC foi igual a 1,00. Os resultados sugerem que é possível obter progresso genético para resistência a carrapato pela seleção.

Estimates of direct and maternal genetic effects for weights from birth to 600 days of age in Nelore cattle

Estimates of direct and maternal variance and heritability for weights at each week (up to 280 days of age) and month of age (up to 600 days of age) in Zebu cattle are presented. More than one million records on 200 000 animals, weighed every 90 days from birth to 2 years of age, were available. Data were split according to week (data sets 1) or month (data sets 2) of age at recording, creating 54 and 21 data sets, respectively. The model of analysis included contemporary groups as fixed effects, and age of dam (linear and quadratic) and age of calf (linear) effects as covariables. Random effects fitted were additive direct and maternal genetic effects, and maternal permanent environmental effect. Direct heritability estimates decreased from 0.28 at birth, to 0.12-0.13 at about 150 days of age, stayed more or less constant at 0.14-0.16 until 270 days of age and increased with age after that, up to 0.25-0.26. Maternal heritability estimates increased from birth (0.01) to a peak of 0.14 for data sets 1 and 0.07-0.08 for data sets 2 at about 180-210 days of age, before decreasing slowly to 0.07 and 0.05, respectively, at 300 days, and then rapidly diminished after 300 days of age. Permanent environmental effects were 1.5 to four times higher than genetic maternal effects and showed a similar trend.

Lifestyle factors and socioeconomic variables associated with abdominal obesity in Brazilian adolescents

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Use of shared memory in the context of embedded multi-core processors: exploration of the technology and its limits

Modern embedded systems embrace many-core shared-memory designs. Due to constrained power and area budgets, most of them feature software-managed scratchpad memories instead of data caches to increase the data locality. It is therefore programmers’ responsibility to explicitly manage the memory transfers, and this make programming these platform cumbersome. Moreover, complex modern applications must be adequately parallelized before they can the parallel potential of the platform into actual performance. To support this, programming languages were proposed, which work at a high level of abstraction, and rely on a runtime whose cost hinders performance, especially in embedded systems, where resources and power budget are constrained. This dissertation explores the applicability of the shared-memory paradigm on modern many-core systems, focusing on the ease-of-programming. It focuses on OpenMP, the de-facto standard for shared memory programming. In a first part, the cost of algorithms for synchronization and data partitioning are analyzed, and they are adapted to modern embedded many-cores. Then, the original design of an OpenMP runtime library is presented, which supports complex forms of parallelism such as multi-level and irregular parallelism. In the second part of the thesis, the focus is on heterogeneous systems, where hardware accelerators are coupled to (many-)cores to implement key functional kernels with orders-of-magnitude of speedup and energy efficiency compared to the “pure software” version. However, three main issues rise, namely i) platform design complexity, ii) architectural scalability and iii) programmability. To tackle them, a template for a generic hardware processing unit (HWPU) is proposed, which share the memory banks with cores, and the template for a scalable architecture is shown, which integrates them through the shared-memory system. Then, a full software stack and toolchain are developed to support platform design and to let programmers exploiting the accelerators of the platform. The OpenMP frontend is extended to interact with it.

The Spatial Signature of Biotic Interactions of a Clonal and a Non-clonal Palmetto in a Subtropical Plant Community

Spatial analyses of plant-distribution patterns can provide inferences about intra- and interspecific biotic interactions. Yet, such analyses are rare for clonal plants because effective tools (i.e., molecular markers) needed to map naturally occurring clonal individuals have only become available recently. Clonal plants are unique in that a single genotype has a potential to spatially place new individuals (i.e., ramets) in response to intra- and interspecific biotic interactions. Laboratory and greenhouse studies suggest that some clonal plants can avoid intra-genet, inter-genet, and inter-specific competition via rootplacement patterns. An intriguing and yet to be explored question is whether a spatial signature of such multi-level biotic interactions can be detected in natural plant communities. The facultatively clonal Serenoa repens and non-clonal Sabal etonia are ecologically similar and co-dominant palmettos that sympatrically occur in the Florida peninsula. We used amplified fragment length polymorphisms (AFLPs) to identify Serenoa genets and also to assign field-unidentifiable small individuals as Sabal seedlings, Serenoa seedlings, or Serenoa vegetative sprouts. Then, we conducted univariate and bivariate multi-distance spatial analyses to examine the spatial interactions of Serenoa (n=271) and Sabal (n=137) within a 20x20 m grid at three levels, intragenet, intergenet and interspecific. We found that spatial interactions were not random at all three levels of biotic interactions. Serenoa genets appear to spatially avoid self-competition as well as intergenet competition. Furthermore, Serenoa and Sabal were spatially negatively associated with each other. However, this negative association pattern was also evident in a spatial comparison between non-clonal Serenoa and Sabal, suggesting that Serenoa genets’ spatial avoidance of Sabal through placement of new ramets is not the explanation of the interspecific-level negative spatial pattern. Our results emphasize the importance of investigating spatial signatures of biotic as well as abiotic interactions at multiple levels in understanding spatial distribution patterns of clonal plants in natural plant communities.

The Long Tail of the Rainbow Serpent: New Technologies and the Protection and Promotion of Traditional Cultural Expressions

New technologies, in particular those stemming from digitisation, allow amongst other things the production of perfect copies, instantaneous and ubiquitous distribution of and easy access to information with no real location restrictions. The effects of these technological advances have largely been perceived as negative for the protection of traditional cultural expressions (TCE), both because of the peculiarities of the digital networked environment and because of the lack of appropriate intellectual property protection models for TCE. The purpose of this article is, while accounting for the diversity and complexity of issues related to TCE, to reveal a more positive side of digital technologies. It shows the potential of these to be proactively applied and the further reaching possibilities for designing an efficient multi-level and multi-faceted toolbox for the protection and promotion of TCE in the digital ecology.

Strong Down-Valley Low-Level Jets over the Atacama Desert: Observational Characterization

The near-surface wind and temperature regime at three points in the Atacama Desert of northern Chile is described using two-year multi-level measurements from 80-m towers located in an altitude range between 2100 and 2700 m ASL. The data reveal the frequent development of strong nocturnal drainage flows at all sites. Down-valley nose-shaped wind speed profiles are observed with maximum values occurring at heights between 20 m and 60 m AGL. The flow intensity shows considerable inter-daily variability and a seasonal modulation of maximum speeds, which in the cold season can attain hourly average values larger than 20 m s−1. Turbulent mixing appears significant over the full tower layer, affecting the curvature of the nighttime temperature profile and possibly explaining the observed increase of surface temperatures in the down-valley direction. Nocturnal valley winds and temperatures are weakly controlled by upper-air conditions observed at the nearest aerological station. Estimates of terms in the momentum budget for the development and the quasi-stationary phases of the down-valley flows suggest that the pressure gradient force due to the near-surface cooling along the sloping valley axes plays an important role in these drainage flows. A scale for the jet nose height of equilibrium turbulent down-slope jets is proposed, based on surface friction velocity and surface inversion intensity. At one of the sites this scale explains about 70% of the case-to-case observed variance of jet nose heights. Further modeling and observational work is needed, however, in order to better define the dynamics, extent and turbulence structure of this flow system, which has significant wind-energy, climatic and environmental implications.

Sportvereine als Interessenorganisationen?! – Ursachen und Auswirkungen von Ziel-Interessen-Divergenzen in freiwilligen Sportorganisationen

Für Sportvereine als Interessenorganisationen scheint die Rückbindung der Vereinsziele an die Mitgliederinteressen von zentraler Bedeutung zu sein. In der Vereinsrealität dürfte aber diese Rückbindung nur teilweise gewährleistet sein und folglich Ziel-Interessen-Divergenzen eher die Norm als die Ausnahme darstellen. Vor diesem Hintergrund stellt sich die Frage, welche Ursachen für Ziel-Interessen-Divergenzen verantwortlich zu machen sind und welche Auswirkungen sich daraus für die Vereine ergeben. Dieser Frage geht der vorliegende Beitrag nach, indem auf der Grundlage des Akteurtheoretischen Mehr-Ebenen-Modells zur Analyse der Entwicklung von Sportvereinen die struktur- und handlungsbedingten Ursachen und Auswirkungen von Divergenzen auf der Vereins- und Mitgliederebene beleuchtet werden. Mit Blick auf die Ursachen wurde der Einfluss der korporativen Vereinsstrukturen und der individuellen Handlungsorientierungen der Mitglieder auf Divergenzen untersucht. Die Befunde hierzu zeigen, dass Divergenzen einerseits durch einem zunehmenden Differenzierungs- und Hierarchisierungsgrad (z.B. Vereinsgröße, Umweltvernetzung, Oligarchisierung) begünstigt werden und andererseits vor allem bei einer primären Verfolgung von Eigeninteressen der Mitglieder auftreten. Hinsichtlich der Auswirkungen wurden die individuellen Mitgliederreaktionen und die korporativen Vereinsreaktionen auf Divergenzen analysiert. Diesbezüglich zeigen die Befunde, dass sowohl die Mitglieder als auch die Vereinsführung überwiegend konstruktiv auf Divergenzen reagieren (z.B. durch Problemansprache, Vertrauen, Kompromissfindung), so dass es vielen Vereinen offenbar relativ gut gelingt, Ziel-Interessen-Divergenzen bis zu einem gewissen Grad sowohl aushalten als auch aufarbeiten zu können.