A nonlocal inhomogeneous dispersal process

AbstractThis article in devoted to the study of the nonlocal dispersal equationut(x,t)=∫RJ(x−yg(y))u(y,t)g(y)dy−u(x,t)in R×[0,∞), and its stationary counterpart. We prove global existence for the initial value problem, and under suitable hypothesis on g and J, we prove that positive bounded stationary solutions exist. We also analyze the asymptotic behavior of the finite mass solutions as t→∞, showing that they converge locally to zero

2-Vector Spaces and Groupoids

This paper describes a relationship between essentially finite groupoids and 2-vector spaces. In particular, we show to construct 2-vector spaces of Vect-valued presheaves on such groupoids. We define 2-linear maps corresponding to functors between groupoids in both a covariant and contravariant way, which are ambidextrous adjoints. This is used to construct a representation--a weak functor--from Span(Gpd) (the bicategory of groupoids and spans of groupoids) into 2Vect. In this paper we prove this and give the construction in detail.Comment: 44 pages, 5 figures - v2 adds new theorem, significant changes to proofs, new sectio

Diversity of gut microflora is required for the generation of B cell with regulatory properties in a skin graft model

B cells have been reported to promote graft rejection through alloantibody production. However, there is growing evidence that B cells can contribute to the maintenance of tolerance. Here, we used a mouse model of MHC-class I mismatched skin transplantation to investigate the contribution of B cells to graft survival. We demonstrate that adoptive transfer of B cells prolongs skin graft survival but only when the B cells were isolated from mice housed in low sterility "conventional" (CV) facilities and not from mice housed in pathogen free facilities (SPF). However, prolongation of skin graft survival was lost when B cells were isolated from IL-10 deficient mice housed in CV facilities. The suppressive function of B cells isolated from mice housed in CV facilities correlated with an anti-inflammatory environment and with the presence of a different gut microflora compared to mice maintained in SPF facilities. Treatment of mice in the CV facility with antibiotics abrogated the regulatory capacity of B cells. Finally, we identified transitional B cells isolated from CV facilities as possessing the regulatory function. These findings demonstrate that B cells, and in particular transitional B cells, can promote prolongation of graft survival, a function dependent on licensing by gut microflora

Building theory of agri-food supply chain resilience using Total Interpretive Structural Modelling and MICMAC analysis

Agri-food supply chains are inherent with some unique characteristics and that can be easily disrupted compared with other supply chains. Therefore, supply chain resilience factors are relevant and can be taken into consideration. In this paper an attempt has been made to build a theoretical framework of resilience factors in agri-food supply chains with the help of total interpretive structural modelling and matrix of cross impact multiplications applied to classification analysis. The results of the total interpretive structural modelling demonstrate that leadership plays a vital role in enhancing the resilience of the agri-food supply chain. Furthermore, the matrix of cross impact multiplications applied to classification analysis results indicate that leadership and working team stability along with strong driving power should be given critical focus by agri-food supply chain managers to facilitate the improvement of agri-food supply chain resilience. This paper contributes to the extant theory building in the field of agri-food supply chain resilience, to fill the gap that a few researches have been conducted on agri-food supply chain resilience theory building

Ligninolytic enzymes activities and SEM analysis of fungal inoculum of Anthracophyllum discolour

Fungal inocula are used for biotechnological applications especially in bioremediation process. They are formulated with a carrier, nutrient sources, binder, and lubricant to be encapsulated for a layer of fungal mycelium. The white-rot fungus Anthracophyllum discolor was studied for its ability to growth actively to form these inocula and to produce ligninolytic enzymes. In this study, fungal inocula were formulated on 3 different mixtures of lignocellulosic materials: F1, F2 and F3 and, two kind of fungal inocula were produced, coated and uncoated. The ligninolytic enzymes Laccase (Lac), Manganese Peroxidase (MnP), Manganese-independent Peroxidase (MiP) and Lignin Peroxidase (LiP) were measured during the experiments. The main enzymatic activity detected was Manganese Peroxidase for F1, F2 and, F3 tested and Laccase had the lowest activity. The amount of total ligninolytic enzyme activity was approximately 40% higher on uncoated than coated pellets, demonstrating the capacity of Anthracophy/lum discolor to growth and produce enzymes on this formulation. Uncoated pellet showed the highest MnP activity, after 15 days in average was 477,13 mmol/min/g being the pick of enzyme at the day 15 with 220,99 mmol/min/g. In contrast for coated pellets the MnP activity was 271,15 mmol/min/g. The UP was not detected on fungal inocula studied. Based on the results of ligninolytic enzymes, the fungal ability to growth and colonization on these pellet formulations showed by scanning electron microscopy (SEM), the pellet uncoated formulated with F1 lignocellulosic materials presents high potential to be used on bioremediation processes. These results will be presented and discussed

Knowledge Mobilization for Agri-Food Supply Chain Decisions: Identification of Knowledge Boundaries and Categorization of Boundary-Spanning Mechanisms

The current world business environment is characterized by increasing uncertainties, complexities, and risks, which require agri-food supply chain (AFSC) managers to respond and act quickly in a context full of instability and unpredictability. Increasing pressure placed on AFSC managers intensifies the need to combine knowledge management (KM) and decision support that rapidly overcome knowledge boundaries. It has been recognized that the research issue related to the knowledge mobilization crossing boundaries in the AFSC needs to be addressed. This paper investigates knowledge boundaries and boundary-spanning mechanisms by collecting data from experienced AFSC practitioners. Empirical results verify that knowledge boundaries such as syntactic boundaries, semantic boundaries, and pragmatic boundaries could be effectively tackled by four specific boundary-spanning mechanisms: boundary spanners, boundary objects, boundary practices, and boundary discourses

Risk analysis of the agri-food supply chain: A multi-method approach

Agri-food supply chains (AFSCs) are becoming more complex in structure, and thus more susceptible to different vulnerabilities and risks. Therefore, to enhance performance, we need to manage the risks in AFSCs effectively and efficiently. This study analyses various AFSC risks using a multi-method approach, including thematic analysis, total interpretive structural modelling (TISM) and fuzzy cross-impact matrix multiplication applied to classification (MICMAC) analysis. Based on the empirical data collected from experienced AFSC practitioners and following thematic analysis, eight categories of risk and 16 risk factors were identified as important. Furthermore, the interrelationships among the identified risks were built using TISM. Finally, the identified risks were classified into various categories according to their dependence and driving power using fuzzy MICMAC analysis. The research results indicate that the weather-related and political risks have the highest driving power and are located at the lowest level in the TISM hierarchy. These risks have a high tendency to disturb the whole flow of AFSC and so should be managed effectively. This study advances existing literature on identifying risk factors, defining interrelations between different AFSC risks, and determining the key risks. The risk analysis results can help AFSC practitioners in AFSC to identify, categorise and analyse the risks

Externalidades del proceso de desarrollo urbano: renovación, rehabilitación y transformación : Búsqueda de nuevas estrategias de sostenibilidad para la implantación

Una preocupación generalizada a la hora de formular y proponer nuevas estrategias sostenibles para las ciudades de América Latina, es cómo enfrentar los procesos de renovación, rehabilitación y transformación de las áreas centrales y su articulación con el resto de la estructura urbana. Este interés no surge sólo en aquellas ciudades con centros históricos de especial notoriedad, sino también en otros casos en que los barrios centrales y pericentrales deteriorados y subutilizados no aportan todo su potencial a la economía y el desarrollo de la ciudad. Las transformaciones físico-espaciales-sociales que se producen en la ciudad generan renovación, rehabilitación y transformación urbana, sin embargo, hay sectores que no asumen este fenómeno generando deterioro y zonas “negras”, las que suelen promover la delincuencia, inseguridad, éxodo de habitantes, etc. (Carrión, 2005; Luque y Smith, 2007, entre otros). La inclusión de grandes áreas periféricas en el espacio urbano y la constitución de nuevos polos de atracción disminuyeron la importancia de las áreas centrales tradicionales. Los sectores de altos ingresos abandonaron los barrios centrales en la medida en que las viviendas tradicionales ya no correspondían a sus estilos de vida, y muchas actividades productivas, comerciales y de servicios emigraron de estas zonas hacia otras áreas de la ciudad más adecuadas a sus nuevos requerimientos funcionales y tecnológicos (Jordan y Simioni, 2003). Con ello, los edificios de los centros urbanos se fueron transformando en viviendas para sectores de menores ingresos y en sedes para actividades económicas menos dinámicas. La prolongada ausencia de inversiones públicas y privadas acentuó las carencias en infraestructura, paralelamente el deterioro y abandono de los espacios de uso colectivo y privado, lo que a su vez contribuyó a disminuir los valores inmobiliarios y aumentar la pobreza, el hacinamiento y la inseguridad en estas áreas centrales. Asociado a ello, gran parte de las transformaciones experimentadas en las últimas décadas, están en estrecha relación con aquellas estrategias sustentadas sobre el capital financiero que pretenden recuperar con mayor velocidad el retorno de los negocios inmobiliarios (Pereira e Hidalgo, 2008). En este contexto, esta ponencia se concentra en establecer ciertos lineamientos estratégicos respecto de la visualización de configuraciones tipológicas en ciertos sectores o áreas de la ciudad que cuentan con las mismas condiciones y variables para producir renovación urbana. Al mismo tiempo, la revisión de algunos casos nos permitirá entender las diferentes dinámicas constitutivas. Por lo tanto, analizar los casos expuestos en relación a las configuraciones urbanas tipológicas nos permite comprender los movimientos y transformaciones que se generan, buscando visualizar ciertos efectos positivos como negativos de modo de establecer estrategias que podrían promover acciones en áreas donde aún no se produce la transformación urbana.Área temática 4: Ciudad, Territorio y Paisaje. Gestión - Eje InvestigaciónFacultad de Arquitectura y Urbanism