Network calibration and metamodeling of a financial accelerator agent based model

We introduce a simple financially constrained production framework in which heterogeneous firms and banks maintain multiple credit connections. The parameters of credit market interaction are estimated from real data in order to reproduce a set of empirical regularities of the Japanese credit market. We then pursue the metamodeling approach, i.e. we derive a reduced form for a set of simulated moments h(\u3b8,s) through the following steps: (1) we run agent-based simulations using an efficient sampling design of the parameter space \u398; (2) we employ the simulated data to estimate and then compare a number of alternative statistical metamodels. Then, using the best fitting metamodels, we study through sensitivity analysis the effects on h of variations in the components of \u3b8 08\u398. Finally, we employ the same approach to calibrate our agent-based model (ABM) with Japanese data. Notwithstanding the fact that our simple model is rejected by the evidence, we show that metamodels can provide a methodologically robust answer to the question \u201cdoes the ABM replicate empirical data?\u201d

A multimeric matrix-associated lectin (RapD) affects proper exopolysaccharide processing in Rhizobium leguminosarum

Rhizobium leguminosarum synthesizes an acidic polysaccharide formed by the polymerization of octasaccharide repeating units containing glucose (Glc), glucuronic acid (GlcA) and galactose (Gal) in a 5:2:1 ratio with particular substitutions; most of it is secreted to the extracellular medium (EPS) and part of it is retained on the bacterial surface as a capsular polysaccharide (CPS). Rap proteins, substrates of the PrsDE type I secretion system (TISS) share at least one Ra/CDHL (cadherin-like) domain and are involved in biofilm and matrix development either by cleaving the polysaccharide (Ply glycanases) or by altering the bacterial adhesive properties. Previous studies have shown that RapA2 is a monomeric calcium-binding lectin capable of binding specifically the R. leguminosarum CPS through a Ra/CDHL domain. It was shown that the absence or excess of RapA2 in the extracellular medium alters the biofilm matrix's properties. In this work we identified a new Rap protein (RapD), which comprises an N-terminal Ra/CDHL domain and a C-terminal domain of unknown function. By Western blot analysis using specific polyclonal antibodies we showed that in planktonic cultures RapD is co-secreted with the other Rap proteins in a PrsDE-dependent manner. Furthermore, under conditions that favor EPS production, a prominent RapD secretion was observed. In addition, colony blot assays indicated that RapD is associated with the biofilm matrix. Interestingly, size exclusion chromatography of the EPS produced by the ΔrapA2 ΔrapD double mutant showed differences in the EPS profiles compared with those of the single mutants and the wild type strain, thus suggesting a functional interaction between the RapA2 and RapD proteins.Biophysical studies showed that calcium triggers proper folding and multimerization of recombinant RapD. Besides, further RapD conformation changes were observed in the presence of EPS. ELISA and BIA (binding inhibition assay) assays showed that in the presence of calcium, RapD specifically binds the EPS and that galactose residues would be involved in this interaction. In conclusion, RapD is a multimeric calcium-dependent EPS lectin that is co-secreted with the other Rap proteins via TISS PrsDE. Unlike RapA2, RapD is not retained on the bacterial surface but would rather interact with the released EPS. Finally, our results suggest that the interaction of RapA2 and RapD with the CPS or the EPS somehow affects the polysaccharide processing and therefore the biofilm matrix.Fil: Tarsitano, Julián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Russo, Daniela Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Alonso, Leonardo Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Nanobiotecnología. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Nanobiotecnología; ArgentinaFil: Zorreguieta, Ángeles. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaProceedings of the Biofilms 9 online conferenceKarslruheAlemaniaKarlsruhe Institute of Technolog

Evaluating North Sea Water Level Monitoring Network Considering Uncertain Information Theory Quantities

Information-theory provides, among others, conceptual methods to quantify the amount of information contained in a random variable, as well as methods to quantify the amount of information contained and shared among two or more variables. Although these concepts have been successfully applied in Hydrology and other fields, the valuation of these quantities is sensible to different parameters used to estimate the probabilities that underline the entropy concept. Typical examples are the bin size of histograms used to compute probabilities and the Kendall correlation coefficient used to estimate copula entropy. The selection of these parameters has subsequent effects on other Information Theory quantities such as Joint Entropy and Total Correlation, which are commonly used in optimization procedures for monitoring networks. The present research aims at introducing a method to take into consideration the uncertainty coming from these parameters in the evaluation of the North Sea’s water level network. The main idea is to represent entropy of random variables through their probability distribution, instead of considering entropy as a deterministic value. The method considers solving multiple scenarios of Multi-Objective Optimization in which, for a given set of stations, information content (Joint Entropy) is maximized and redundancy (Total Correlation) is minimized. These scenarios are generated with parameter sampling methods such as the Latin Hypercube. Results include probabilistic analysis of the chosen parameters on the resulting family of Pareto fronts, providing additional criteria on the selection of the final set of monitoring points and the elimination of redundant/non-informative points. Data used was the raw data available from the Dutch Ministry of Infrastructure and Environment. The resulting water level monitoring network will be compared to the one obtained by other methods that will be described in a report currently under preparation, which will be publicly available soon in the Deltares websit

The Hilton hotels in the midst of the UAE 2071 centennial plan: Redesigning the UAE on the path of innovation and international tourism

Motivated by the strategy of economic diversification and the consequent transformations in the tourism and hospitality sector of the United Arab Emirates (UAE) mainly from implementing a long-term vision through the UAE Centennial Plan 2071, the case aims to put students in the role of Jan Schneider, president of the Hilton Hotels for the Middle East and Africa, so that they can propose an expansion strategy for the group in the country and region. In this context, some strategic challenges related to institutional uncertainties and the possible increase in market competitiveness need to be addressed. The case was designed for undergraduate and graduate students of business administration and hotel management who want to discuss topics such as entry strategies and international expansion of hotel ventures

¿Una nueva ola autoritaria?

This paper presents the mechanisms that lead from a democracy to democratic deterioration, crisis, conversion to a hybrid regime, and change to authoritarianism. For this purpose, processes related to the context of polarization, personalization and political radicalization are analyzed, which affect the qualities of democracy, leading to authoritarian regressions. The cases of Poland, Hungary, Venezuela and Turkey are analyzed.En este trabajo se presentan los mecanismos que llevan desde una democracia hacia el deterioro democrático, crisis, conversión en régimen híbrido, y cambio hacia el autoritarismo. Para ello, se analizan procesos vinculados con el contexto de polarización, personalización y radicalización política, que afectan las calidades de la democracia, dando lugar a regresiones autoritarias. Se analizan los casos de Polonia, Hungría, Venezuela y Turquía

DIAMOND OF THE DESERT: THE CASE OF QATAR’S 2022 FIFA WORLD CUP

For the first time in the Arab world, the FIFA World Cup in Qatar 2022 was one of the main drivers for promoting important infrastructural changes in the country, as well as for transforming the image of Qatar in order to make the destination more attractive to foreign tourists. However, despite the great wealth from its Oil & Gas reserves, several social challenges that historically affect the country began to emerge due to greater coverage of the international media, threatening the expectations of positive legacies left on the country\u27s image from the event. Given this context, the case puts the reader in the role of Ahmed Al-Nasr, then Chairman of the Qatar Supreme Committee for Delivery and Legacy, as he faces different pressures made by major international brands sponsoring the event who now see their image threatened by successive controversies that the country has been involved in and they are threatening to withdraw their support and investments. The case is indicated for undergraduate and graduate students of courses in the area of Tourism, Sport Management, and Business interested in discussing topics and concepts related to environmental, social, and governance (ESG) responsibility, management of mega events, international marketing, and country destination image

A Combined 90/900 MHz IC Architecture for Smart Tag Application

In this work we present a combined 90/900 MHz Energy Harvesting Architecture for active smart tag Application. The harvester takes advantages from a dedicated diplexer and a power manager for battery life enhancement purposes. The system has been optimized in the 900 MHz frequency range by analyzing a probabilistic approach used for modeling the possible amount of Global System for Mobile communication (GSM) energy that could be harvested while a fixed power downlink scenario has been adopted for the 90MHz band. A preliminary IC system with a 0.18μm CMOS SMIC technology has been designed and optimized at 90 and 900 MHz while discrete element board, to be integrated with the proposed IC, with commercial components has been developed and tested. Concerning simulation results on the IC design they have confirmed that the integrated system handles an incoming power typically ranging from -25 dBm to 5 dBm by rectifying the variable input signals into a DC voltage source with an average 50% efficiency

RapD Is a Multimeric Calcium-Binding Protein That Interacts With the Rhizobium leguminosarum Biofilm Exopolysaccharide, Influencing the Polymer Lengths

Rhizobium leguminosarum synthesizes an acidic polysaccharide mostly secreted to the extracellular medium, known as exopolysaccharide (EPS) and partially retained on the bacterial surface as a capsular polysaccharide (CPS). Rap proteins, extracellular protein substrates of the PrsDE type I secretion system (TISS), share at least one Ra/CHDL (cadherin-like) domain and are involved in biofilm matrix development either through cleaving the polysaccharide by Ply glycanases or by altering the bacterial adhesive properties. It was shown that the absence or excess of extracellular RapA2 (a monomeric CPS calcium-binding lectin) alters the biofilm matrix’s properties. Here, we show evidence of the role of a new Rap protein, RapD, which comprises an N-terminal Ra/CHDL domain and a C-terminal region of unknown function. RapD was completely released to the extracellular medium and co-secreted with the other Rap proteins in a PrsDE-dependent manner. Furthermore, high levels of RapD secretion were found in biofilms under conditions that favor EPS production. Interestingly, size exclusion chromatography of the EPS produced by the ΔrapA2ΔrapD double mutant showed a profile of EPS molecules of smaller sizes than those of the single mutants and the wild type strain, suggesting that both RapA2 and RapD proteins influence EPS processing on the cell surface. Biophysical studies showed that calcium triggers proper folding and multimerization of recombinant RapD. Besides, further conformational changes were observed in the presence of EPS. Enzyme-Linked ImmunoSorbent Assay (ELISA) and Binding Inhibition Assays (BIA) indicated that RapD specifically binds the EPS and that galactose residues would be involved in this interaction. Taken together, these observations indicate that RapD is a biofilm matrix-associated multimeric protein that influences the properties of the EPS, the main structural component of the rhizobial biofilm.Fil: Tarsitano, Julián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Ramis, Lila Yanina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Alonso, Leonardo Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Nanobiotecnología. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Nanobiotecnología; ArgentinaFil: Russo, Daniela Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Zorreguieta, Ángeles. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentin

Introducción

En este conjunto de trabajos, con el que se inaugura la Revista Euro Latinoamericana de estudios sociales y políticos, se cuenta con el aporte de estudiosos de distintos países de América Latina y Europa, a fin de precisar, desde enfoques de la ciencia política, la sociología y la historia, algunos de los problemas y alternativas de desarrollo que afrontan las democracias a ambos lados del atlántico. Un dossier de investigaciones como este puede presentarse de modo individual, comentando cada trabajo, o según las familias de problemas teóricos y de subtemáticas que se abordan. Partimos de esta segunda opción a fin de mostrar los puntos de confluencia, así como para reforzar el sentido que cada trabajo aporta a la discusión colectiva sobre las democracias y la política actual

Estudio comparativo de estrategias heurísticas de generación de soluciones para el problema de asignación de exámenes

Timetabling se refiere a un conjunto de problemas de optimización combinatoria, que intentan asignar recursos, sean aulas, docentes o intervalos de tiempo para distintas necesidades de estudiantes, cursos y exámenes. En el presente trabajo se aborda una de las variantes de este problema que busca agendar exámenes a distintos intervalos de tiempo, cumpliendo con las restricciones de que ningún alumno debe asistir a más de un examen en el mismo momento y, en la medida de lo posible, que tenga el mayor tiempo libre entre las evaluaciones. La cantidad de combinaciones a considerar para una instancia tamaño moderado hacen inviable la búsqueda de la solución óptima, debido al tiempo que demandaría encontrarla. En consecuencia, en este artículo se utilizan distintas estrategias para combinar heurísticas que permiten obtener una buena solución al problema en un intervalo de tiempo reducido. Las heurísticas mencionadas fueron probadas sobre un conjunto de instancias estándar de manera individual así como también combinadas de manera secuencial yjerárquica. En las pruebas realizadas se obtuvieron mejores resultados mediante el método jerárquico. Debido a lo anterior es posible afirmar la superioridad de este último método sobre los demás utilizados en el presente trabajo