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

Benchmarking a many-core neuromorphic platform with an MPI-based DNA sequence matching algorithm

SpiNNaker is a neuromorphic globally asynchronous locally synchronous (GALS)multi-core architecture designed for simulating a spiking neural network (SNN) in real-time. Several studies have shown that neuromorphic platforms allow flexible and efficient simulations of SNN by exploiting the efficient communication infrastructure optimised for transmitting small packets across the many cores of the platform. However, the effectiveness of neuromorphic platforms in executing massively parallel general-purpose algorithms, while promising, is still to be explored. In this paper, we present an implementation of a parallel DNA sequence matching algorithm implemented by using the MPI programming paradigm ported to the SpiNNaker platform. In our implementation, all cores available in the board are configured for executing in parallel an optimised version of the Boyer-Moore (BM) algorithm. Exploiting this application, we benchmarked the SpiNNaker platform in terms of scalability and synchronisation latency. Experimental results indicate that the SpiNNaker parallel architecture allows a linear performance increase with the number of used cores and shows better scalability compared to a general-purpose multi-core computing platform

What Courses Do I Need to Teach in Order to Address Food Insecurity in Sub Saharan Africa? A Delphi Study

Sub Saharan Africa is a region that has been struggling with food insecurity for decades. Though the percentage of undernourished people in the region has decreased over the last 25 years, the actual number of undernourished people increased by more than forty million. Combatting food insecurity in the region requires an arsenal of skills, knowledge, and abilities across a broad range of disciplines. One way to target food insecurity is through education and capacity building. The purpose of this study was to identify the courses and topics that should be included in a food security (FS) graduate certificate focused on Sub Saharan Africa. Identification of the topics and courses came from faculty and professionals working in the FS field in Sub Saharan Africa. A three-round Delphi technique was conducted to accomplish the purpose of the study with a total of 63 experts. Of the original 101 topics that the expert panel proposed in Round One, 80 reached the level of agreement. Researchers grouped the topics into 28 courses. The final result of the study was 24 courses that reached the level of agreement for determining the main topics and courses that should be included in a graduate certificate focused on FS for Sub Saharan Africa

One-Step Laparoscopic Management of a Female Adnexal Tumor of Wolffian Origin

We report a case of female adnexal tumor of Wolffian origin (FATWO), a rare neoplasm arising from the mesonephric ducts. A 48-year-old woman came first to our center for a recent discovery of a pelvic mass. Transvaginal ultrasonographic findings suggested a solid right para-ovarian mass suspected to be malignant. After thorough counseling, the patient underwent operative laparoscopy for excision of the para-ovarian mass with frozen section (FS) examination resulting in the diagnosis of a poorly differentiated adenocarcinoma. In this case, FS results allowed performing a comprehensive oncological staging, through a totally laparoscopic extrafascial hysterectomy, bilateral adnexectomy, total omentectomy, pelvic wall peritonectomy, and pelvic, parasacral and para-aortic lymphadenectomy. Final pathological and immunohistochemical results confirmed the diagnosis of FATWO. To our knowledge, this is the first case of FATWO managed entirely by a minimally invasive laparoscopic approach in a single surgical session

Integrated plan for the sustainable management of the Lagoon of Marano and Grado

The Lagoon of Marano and Grado has been experiencing some remarkable environmental impacts, which have affected the high-value natural ecosystem and consequently influenced relevant socio-economic aspects. One of the main problems relates to the diffuse contamination of soil and groundwater in the mainland, as well as sediments in rivers and in the lagoon itself. The need to ensure safe navigation conditions in the lagoon and in the Corno River serving Porto Nogaro harbour is another critical emergency. Other environmental issues of concern are: loss of morphological diversity, watershed basins’ pollution loads and protection of lagoon habitats. Due to the emergency situation, a Special Commissioner has been appointed by the national government to proceed with the resolution of the most critical problems. A specific “Operational Plan of interventions” was therefore elaborated in 2009. Approaching problems and solutions in an integrated way, the Plan represents one of the tools for the sustainable development of the lagoon. It strongly supports the adoption of adaptive management, foreseeing the periodical updating and improvement of objectives, strategies and interventions. The Plan also identifies the need for coordination among institutions and involvement of stakeholders as key elements for the implementation of adaptive management

Geological and Hydrogeological Characterization of Springs in a DSGSD Context (Rodoretto Valley – NW Italian Alps)

As continuous groundwater monitoring in the upper sector of Rodoretto Valley (Germanasca Valley, Italian Western Alps) is hampered by logistical problem of data collection during winter and spring months, the only tools currently available to derive hydrogeological information are non-continuous and non-long-term dataset of spring discharge (Q), temperature (T) and electrical conductivity (EC). In order to quantity aquifer groundwater reserve, available Q dataset of a small mountain spring (Spring 1 CB) was investigated by applying the analytical solutions developed by Boussinesq (J Math Pure Appl 10:5–78, 1904) and Maillet (Essais dı’hydraulique souterraine et fluviale, vol 1. Herman et Cie, Paris, 1905); T and EC datasets were also used to provide qualitative information about the nature of the aquifer that supplies the spring. The outcomes of the elaborations highlighted the limits of applicability of these methods in the presence of a non-continuous Q dataset: both Boussinesq (J Math Pure Appl 10:5–78, 1904) and Maillet (Essais dı’hydraulique souterraine et fluviale, vol 1. Herman et Cie, Paris, 1905) estimated that discharge values as a function of recession time were found to be consistently lower than the available discharge ones and the estimated groundwater volumes stored over time above the spring level turned out to be underestimated. Continuous (hourly value) and long-term Q, EC and T values are, therefore, needful to correctly quantify and to make a proper management of groundwater resources in mountain areas

Mouse allergen, lung function, and atopy in Puerto Rican children

Objective: To examine the relation between mouse allergen exposure and asthma in Puerto Rican children. Methods: Mus m 1, Der p 1, Bla g 2, and Fel d 1 allergens were measured in dust samples from homes of Puerto Rican children with (cases) and without (controls) asthma in Hartford, CT (n = 449) and San Juan (SJ), Puerto Rico (n = 678). Linear or logistic regression was used for the multivariate analysis of mouse allergen (Mus m 1) and lung function (FEV1 and FEV1/FVC) and allergy (total IgE and skin test reactivity (STR) to ≥1 allergen) measures. Results: Homes in SJ had lower mouse allergen levels than those in Hartford. In multivariate analyses, mouse allergen was associated with higher FEV1 in cases in Hartford (+70.6 ml, 95% confidence interval (CI) = 8.6-132.7 ml, P = 0.03) and SJ (+45.1 ml, 95% CI = -0.5 to 90.6 ml, P = 0.05). In multivariate analyses of controls, mouse allergen was inversely associated with STR to ≥1 allergen in non-sensitized children (odds ratio [OR] for each log-unit increment in Mus m 1 = 0.7, 95% CI = 0.5-0.9, P<0.01). In a multivariate analysis including all children at both study sites, each log-increment in mouse allergen was positively associated with FEV1 (+28.3 ml, 95% CI = 1.4-55.2 ml, P = 0.04) and inversely associated with STR to ≥1 allergen (OR for each log-unit increment in Mus m 1 = 0.8, 95% CI = 0.6-0.9, P<0.01). Conclusions: Mouse allergen is associated with a higher FEV1 and lower odds of STR to ≥1 allergen in Puerto Rican children. This may be explained by the allergen itself or correlated microbial exposures. © 2012 Forno et al