On Sevillian guilds towards the end of the 11th century

In the third decade of the 20th century, Lévi-Provençal discovered an Arab manuscript by the ishbīlī Ibn cAbdūn, that dealt with the commercial and artisan practices in Seville at the end of the 11th century. In the document there were references to the offices and personages who had to perform certain functions in various professions. From this manuscript, Lévi-Provençal deduced the existence of 11th-century Islamic guilds in Seville. This idea was assumed by Spanish historians, even up until the final decade of the 20th century. In the present article, the basis which sustained such an idea is analyzed with particular emphasis on the treatise by Ibn cAbdūn, since this is the only work that describes the economy of Seville at the time of Classic Islam (before the 12th century), and since this is the principal historical source cited by recent historians as a guarantee of the existence of Sevillian guilds during the Classic Islam; however, other manuscripts of Islamic authors of al-Andalus, and articles of contemporary authors are also taken into account. The result of our investigation disproves the existence of 11th century Islamic guilds in SevilleEn la tercera década del siglo XX Lévi-Proveçal descubrió un manuscrito árabe del išbīlī Ibn cAbdūn, donde se tratan las prácticas comerciales y artesanales en Sevilla a finales del siglo XI. En él hay referencias a los oficios y a personajes que debían cumplir determinadas funciones sobre la profesión. De ahí Lévi-Provençal dedujo la existencia de gremios islámicos en Sevilla. Esta idea resultó ser sugestiva y fue asumida por historiadores españoles del siglo XX, incluso en la década final de ese siglo. En el presente artículo se analizan las bases que sustentaron tal idea, haciéndose especial hincapié en el Tratado de Ibn cAbdūn por ser la única obra que se refiere a la economía de Sevilla en la época del islam clásico (antes del siglo XII) y la principal fuente histórica mencionada por dichos historiadores recientes como garantía de la existencia de gremios sevillanos durante el islam; sin embargo, también se tendrán en cuenta otros manuscritos de autores islámicos de al-Andalus y artículos de autores contemporáneos. El resultado de nuestra investigación refuta la existencia de gremios islámicos en la Sevilla del siglo X

Some Evidence of Smooth Transition Nonlinearity in Colombian Inflation

Evidence of smooth transition autoregressive (STAR) representations is found in two, out of three, time series of different measures of annual inflation in Colombia during this decade for monthly data. The STAR-type nonlinearities are asymmetric for inflation computed as the variation of CPI while for (a measure of) core inflation are symmetric. Thus, LSTAR and ESTAR models were, respectively, estimated. No evidence of nonlinearity is found for traded goods inflation. Given the local dynamic properties of the estimated LSTAR model, only positive shocks to prices could shift negative accelerating inflation rate from the upper to the lower regime. By the same token, only stochastic shocks can move the core accelerating inflation rate from the outer regime to the middle one but the explosive nature of this regime will impulse accelerating inflation rate to the outer one.nonlinearity, core inflation, regimes, logistic and exponential transition functions.

PTP1B promotes focal complex maturation, lamellar persistence and directional migration

Previous findings established that ER-bound PTP1B targets peripheral cell-matrix adhesions and positively regulates cell adhesion to fibronectin. Here we show that PTP1B enhances focal complex lifetime at the lamellipodium base, delaying their turnover and facilitating α-actinin incorporation. We demonstrate the presence of catalytic PTP1BD181A-α-actinin complexes at focal complexes. Kymograph analysis revealed that PTP1B contributes to lamellar protrusion persistence and directional cell migration. Pull-down and FRET analysis also showed that PTP1B is required for efficient integrin-dependent downregulation of RhoA and upregulation of Rac1 during spreading. A substrate trap strategy revealed that FAK/Src recruitment and Src activity are essential for the generation of PTP1B substrates in adhesions. PTP1B targets the negative regulatory site of Src (phosphotyrosine 529), paxillin and p130Cas at peripheral cell-matrix adhesions. We postulate that PTP1B modulates more than one pathway required for focal complex maturation and membrane protrusion, including α-actinin-mediated cytoskeletal anchorage, integrin-dependent activation of the FAK/Src signaling pathway, and RhoA and Rac1 GTPase activity. By doing so, PTP1B contributes to coordinated adhesion turnover, lamellar stability and directional cell migration.Fil: Burdisso, Juan Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: González, Angela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Arregui, Carlos Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; Argentin

The differentiated impact of role models and social fear of failure over the entrepreneurial activities of rural youths

The main objective of this study is to determine the differential impact of certain socio-cultural variables (such as entrepreneurial self-confidence, role models and fear of failure) on the entrepreneurial process of Spanish rural youths. In consonance with the new rural policy paradigm, the European Commission and the OECD are proposing entrepreneurship as a tool for economic diversification and endogenous rural development. Entrepreneurship is associated in rural areas with economic vitality and prosperity. Entrepreneurship in rural areas becomes a means for capturing and optimizing the true natural, social and human capital of a territory as well as a source of opportunity and welfare for the local population. However, in a context where many rural areas are suffering from an aging and retiring population, the emphasis on developing an entrepreneurially active community becomes especially important within the segment of rural youths. Environmental and social-cultural factors have been used to explain differences in entrepreneurship across territories, including the rural urban divide. This line of research has found that certain variables, such as the local presence of role models and the social stigma of failure, have a differential impact over entrepreneurial activity across certain segments of the population (gender, immigrant status). Therefore, this study has the objective to verify whether age affects the impact that certain socio-cultural variables have on the entrepreneurial process of rural and urban youths. The methodology used in this study is the logistic regression model for rare events, with a database of the Global Entrepreneurship Monitor in Spain for 2009, which has a sample of 26,990 adults. The study shows that young adults in Spain have a higher propensity for entrepreneurial activity than the rest of the population, but discriminating between urban and rural youth, the latter are less likely to be entrepreneurs. Amongst younger-aged individuals, social-cultural factors are found to have a differential impact on entrepreneurship across the rural-urban divide.Peer ReviewedPostprint (author’s final draft

Modelo de Gestión Territorial utilizado en la reconstrucción post terremoto y tsunami del 27-F en Chile

En Chile, el terremoto y tsunami ocurridos el 27 de Febrero del año 2010, intensidad 8,8 ° en la escala de Richter, dejaron en absoluta evidencia la necesidad de reconstruir planificadamente pequeñas localidades y caletas pesqueras ubicadas en la costa de la zona central del país, área donde la catástrofe generó los mayores daños físicos, sociales y económicos. Por este motivo, desde el año 2010 en adelante, el Estado de Chile puso en marcha una serie de adyacencias creativas que han buscado alcanzar un diseño urbano sostenible en todos los centros urbanos que fueron devastados a causa, principalmente, del tsunami. El propósito Estatal se materializó a través de Planes Maestros de Reconstrucción Territorial, cuyo objetivo fue articular equipos multidisciplinarios para lograr la implementación de planes de reconstrucción integrales e innovadores en su modelo de gestión y simultáneamente, mediante la sumatoria de micro-estrategias urbanas, desarrollar imágenes de un futuro posible en aquellos poblados. A partir de la experiencia chilena, se aborda como caso estudio el Plan de Reconstrucción Estratégico Sustentable, comúnmente conocido como PRES, de las localidades de Duao, Iloca y La Pesca, ubicadas en la Región del Maule. Mediante este caso se reflejan éxitos y desaciertos de la asociatividad entre entidades públicas e instituciones privadas en la planificación territorial, en un contexto de emergencia post desastre natural. Además, el resultado esperado es evidenciar el rol protagónico asumido por actores privados en la planificación territorial chilena en un contexto de emergencia, en el momento en que el Estado baja las barreras normativas. En términos metodológicos, la investigación se desarrolla mediante lo que Jacques Derrida denominó Deconstrucción, es decir, la descomposición de los diferentes elementos teóricos que componen el tema, para analizarlos separadamente y para abordarlos posteriormente desde una perspectiva global.The Chilean earthquake and tsunami on February 27th 2010, which had an intensity of 8.8° Richter it was a phenomenon that made more than evident the Chilean necessity of a coastline planning, namely in villages and coves located in central region of the country. Exactly in this region the catastrophe was where it made the major physical, social and economic damage. For these reasons, from 2010 onwards, the Chilean Government began to develop a group of creatives adjacencies that had as target to make a sustainable urban design in all the urban places that were destroyed by tsunami. The Government purpose was materialised by Territorial Reconstruction Master Plans, which took the responsibility of articular multidisciplinary teams and thus to achieve the reconstruction plan implementation through the sumatory of micro urban strategies for these villages. In this research the case of study is the Sustainable Strategic Reconstruction Plan (PRES due to its initials in Spanish) of Duao, Iloca and La Pesca, located in Maule Region. This case shows success and mistakes of the public and private associativity in the urban development within an emergency context post natural disaster. Besides, the result of this research make evident the protagonist role that private institutions assume in emergency context, because in this time the Government come down suddenly the normative obstacle. The methodology is through the deconstruction of each part of the theoretical contents

Firm Failure and Relationship Lending:New Evidence from Small Businesses

We study the effect of relationship lending on small firms failure probability using a uniquely rich data set comprised of information on individual loans of a large number of small firms in Colombia. We control for firm-specific variables and find that small firms involved in long-term liaisons with commercial banks have a significantly lower probability of becoming bankrupt than otherwise identical firms not involved in a long-term credit relationship. We also find that small firms with multiple banking relationships face a lower failure hazard than otherwise identical firms involved in a unique long-term relationship.Firms, bank relationships, survival analysis. Classification JEL: G20, G21, C40.