PRELIMINARY BOTANICAL ASSESSMENT OF PRODUCTION CHALLENGES OF CASHEW (ANACARDIUM OCCIDENTALE L.) IN LAFIA, NASARAWA STATE, NIGERIA

The aim of this study was to investigate the production and challenges of cashew farming in Lafia, Nigeria. The study area was divided into five zones. Fifty semi-structured questionnaires were administered to the farmers. The results showed that only males are engaged in cashew farming and slightly above 95% are married and just about 44% are aged between 21-40 y. Over 95% of farmers disclose that cashew production is seasonal; slightly above 73% disclose that diseases and pests are major challenges in cashew cultivation. Over 64% are of the opinion that these diseases and pests are responsible for yield reduction. Slightly above 52% disclose that yellow cashew is the most tasty and best for consumption. 52% of the farmers agree that 2017 is their best year of harvest because they were more involved in the management. 44% of farmers disclose that they do not apply chemicals and cultural practice in controlling diseases and pests, however majority agree that chemicals are useful in weed control. There was no agreement about the flowering and fruiting periods of cashew as 57% believe that cashew trees flower once, during the dry season and 65% disclosed that flowering occurs between January and March each year

What is life? A perspective of the mathematical kinetic theory of active particles

The modeling of living systems composed of many interacting entities is treated in this paper with the aim of describing their collective behaviors. The mathematical approach is developed within the general framework of the kinetic theory of active particles. The presentation is in three parts. First, we derive the mathematical tools, subsequently, we show how the method can be applied to a number of case studies related to well defined living systems, and finally, we look ahead to research perspectives

Spatial interactions in agent-based modeling

Agent Based Modeling (ABM) has become a widespread approach to model complex interactions. In this chapter after briefly summarizing some features of ABM the different approaches in modeling spatial interactions are discussed. It is stressed that agents can interact either indirectly through a shared environment and/or directly with each other. In such an approach, higher-order variables such as commodity prices, population dynamics or even institutions, are not exogenously specified but instead are seen as the results of interactions. It is highlighted in the chapter that the understanding of patterns emerging from such spatial interaction between agents is a key problem as much as their description through analytical or simulation means. The chapter reviews different approaches for modeling agents' behavior, taking into account either explicit spatial (lattice based) structures or networks. Some emphasis is placed on recent ABM as applied to the description of the dynamics of the geographical distribution of economic activities, - out of equilibrium. The Eurace@Unibi Model, an agent-based macroeconomic model with spatial structure, is used to illustrate the potential of such an approach for spatial policy analysis.Comment: 26 pages, 5 figures, 105 references; a chapter prepared for the book "Complexity and Geographical Economics - Topics and Tools", P. Commendatore, S.S. Kayam and I. Kubin, Eds. (Springer, in press, 2014

Growing Smart Cities

As the world’s population becomes increasingly urbanised the problems of building sustainable cities also grows. Using Susan Stepney’s response, “Mighty Oaks from Little Acorns Grow”, to a science fiction story by Adam Marek titled “Growing Skyscrapers”, this chapter looks at what a living city of the future might look like, and how that might solve some of the problems of the control and development of cities. There is a long history of the application of systems thinking, cybernetics, and complex systems and the growth and control of cities. However, many problems still remain in the deployment and applications of these frameworks and methodologies, and in the potential consequences of their use. However, perhaps many of these could be solved by the development of a living city

Rethinking macroeconomics with endogenous market structure

Do entry, exit and changes in market structure aect the macroeconomy? Is there a link between the strategic interactions among oligopolistic rms and the macroeconomic equilibrium? The question is certainly not trivial in modern economies, where large oligopolistic rms play a relevant role and so many meetings among statesmen have the explicit scope of promoting contracts for some large and important rms of their countries. However, surprisingly enough, the most popular theoretical models in the modern macroeconomic literature hardly see any explicit formalization for the macroeconomic eects of changes in market structure, entry, exit and strategic interactions among oligopolists, if not as mere mechanic and secondary eects of the usual technology shocks, commonly invoked as the cause of business cycle. Do we really think that the sophisticated strategies of large rms' decision makers do not carry any macroeconomic consequences? The market structure and strategic interactions among oligopolists are not necessarily associated to scale economies or technology shocks. In order to better focus on this point, the theoretical model of this book describes, like some of the most important original contributions in the conventional DSGE literature, an economy where the labor is the only production input. This book deals with all these issues by introducing a new macroeconomic approach: part ONE provides its theoretical background and modelling framework, part TWO its implications by running some simulations and comparing the results with the US macroeconomic data