Nonorientable 3-manifolds admitting coloured triangulations with at most 30 tetrahedra

We present the census of all non-orientable, closed, connected 3-manifolds admitting a rigid crystallization with at most 30 vertices. In order to obtain the above result, we generate, manipulate and compare, by suitable computer procedures, all rigid non-bipartite crystallizations up to 30 vertices.Comment: 18 pages, 3 figure

Geometric group presentations: a combinatorial approach

In this paper we obtain combinatorial conditions for the geometricity of group presentations; our criterion holds both for orientable and for non-orientable manifolds

Moyano, Daniel. Desde la empresa. Firmas familiares y estructura empresarial en la industria azucarera tucumana, 1895-1930. Buenos Aires: Prometeo Libros, 2015, 210 p. ISBN 9875746762. : algo más sobre el azúcar: agroindustria y renovación historiográfica

Fil: Bandieri, Susana. Universidad Nacional del Comahu

Ruolo dell'etilendiurea (EDU) nella protezione di piante di frassino (Fraxinus excelsior) dai danni da ozono: aspetti fisiologici e biochimici

L’Europa, ed in particolar modo quella meridionale, è interessata da concentrazioni molto elevate di ozono (O3) troposferico in grado di influenzare negativamente la crescita della vegetazione. Gli effetti dannosi dell’O3 sulle piante forestali non sono ancora completamente chiari, principalmente a causa delle tecniche sperimentali che non permettono di trasferire le risposte ottenute in condizioni controllate a quelle ambientali. L’etilendiurea (EDU) è una sostanza chimica sistemica e persistente che costituisce una metodologia alternativa di studio delle complesse relazioni O3-vegetazione soprattutto in condizioni di ambiente naturale. L’esperimento svolto nel 2005, ha interessato piante adulte di frassino (Fraxinus excelsior L.) localizzate nel parco “Millerose” a Torino, cresciute in condizioni naturali e in presenza di elevati livelli ambientali di O3 (32,5 ppm h AOT40 per tutta la stagione di crescita). Tali piante sono state distinte in sensibili e tolleranti all’O3, in relazione alla presenza o assenza di sintomi fogliari osservati nell’anno precedente a quello di sperimentazione; entrambe le tipologie di piante sono state poi trattate con EDU (450 ppm) o con acqua attraverso infusioni gravitazionali nel tronco per tutta la stagione di crescita, con somministrazioni periodiche ad intervalli di 21 giorni. Il presente studio è volto ad indagare alcune risposte biometriche, biochimiche e fisiologiche da parte delle due tipologie di piante (sensibili e non) in condizioni reali di esposizione cronica all’inquinate, per comprendere sia i meccanismi potenzialmente coinvolti nella diversa sensibilità che gli effetti dell’applicazione dell’EDU. L’EDU non ha influito in modo significativo sui parametri di crescita e fisiologici come mostrato dall’assenza di variazioni nel numero di foglie e foglioline, nel diametro e nella lunghezza dei germogli (parametri di crescita); così come dalla mancanza di variazioni a carico della fotosintesi netta, della respirazione notturna e della conduttanza stomatica misurata sia di giorno che di notte (parametri fisiologici). In analogia e a conferma degli scarsi effetti registrati a livello del processo fotosintetico, il trattamento con EDU non determinava modificazioni neppure a carico dello stato di attivazione del ciclo fotoprotettivo delle xantofille. Più complesse sono state invece le risposte relative all’attivazione dei meccanismi antiossidanti enzimatici e non, propri delle piante. A livello apolastico, infatti, il trattamento con EDU ha determinato nelle piante sintomatiche un abbattimento delle alte concentrazioni di H2O2 riscontrate nelle piante trattate con acqua. Questo dato, in aggiunta al minor contenuto in acido ascorbico ridotto (ASA) e alla mancata stimolazione dell’attività dell’ascorbico perossidasi (APX), potrebbe suggerire un’azione diretta dell’EDU nelle detossificazione delle ROS nel comparto apoplastico. Le piante asintomatiche non risultavano invece particolarmente influenzate. A livello intracellulare si evidenziava una risposta differente da parte delle due tipologie di piante: infatti, nel caso delle asintomatiche l’EDU sembrava stimolare la sintesi dell’acido ascorbico, mentre in quelle sintomatiche il trattamento aveva effetti positivi sull’attività dell’APX. Nessuna influenza da parte dell’EDU è stata invece osservata sull’attività della deidroascorbico riduttasi e della glutatione riduttasi, enzimi coinvolti nel ciclo di Halliwell-Asada nell’ambito del quale avviene la rigenerazione dell’acido ascorbico nella forma ridotta, cioè metabolicamente attiva contro le ROS. L’insieme dei dati ottenuti ha evidenziato come l’effetto dell’EDU si esplichi principalmente determinando modificazioni a carico dei sistemi antiossidanti piuttosto che influenzando parametri fisiologici. Inoltre, l’osservazione di una risposta diversificata tra piante sintomatiche e non sottolinea l’importanza dei fattori genetici nel determinare la capacità di reazione agli stimoli ambientali, anche nell’ambito della stessa specie e rende necessario estendere la ricerca allo studio di altri sistemi antiossidanti e meccanismi di difesa

Más acá del Colorado: historia regional y relaciones fronterizas en la Norpatagonia argentina, el caso de Neuquén

En el caso de la provincia de Neuquén, ubicada en el noroeste de la región patagónica argentina, las condiciones de mediterraneidad y aislamiento confirieron al territorio una particular singularidad. La cordillera de los Andes, por su especial accesibilidad, sirvió históricamente y desde las primeras etapas de ocupación indígena, de eje vertebrador de un espacio integrado social y económicamente con las provincias del sur chileno, que actuó y sobrevivió por encima de los límites políticos y administrativos impuestos al territorio a partir de su conquista militar. Esto generó en el proceso histórico neuquino cierto grado de especialización regional con su propio esquema de funcionamiento e intercambio y una organización socio-espacial acorde que admite un tratamiento diferencial. De hecho, no es posible pensar la historia de la región atendiendo solamente a sus límites territoriales, sin considerar la importancia de un área de frontera con existencia propia donde se definió históricamente un particular espacio social de larga duración y alta complejidad.The province of Neuquén is located in northwest Patagonia region of Argentina. There, landlocked conditions and isolation conferred a special uniqueness to the territory. The Andes, with its special accessibility was used historically, from the earliest stages of indigenous occupation, like the backbone of an socially and economically integration in between the provinces of southern Chile and Argentina. That region survived over the political and administrative boundaries fixed on the territory from the times of its military conquest. This resulted in the historical process, wher Neuquen become in a regional specialization with its own operation and exchange. That scheme and a consistent socio-spatial organization supports differential treatment. In fact, it’s no possible to think the history of the region paying atention to their territorial limits only. Considering the importance of a frontier area where existence itself is defined historically, particularly as an social space for it long terme and high complexity, should be of the highest interest.Fil: Bandieri, Susana Ofelia. Unidades En Red - Conicet. Investigaciones Socio-historicas Regionales. Centro de Estudios de Historia Regional - Nodo Cehir - Ishir; Argentin

Complexity computation for compact 3-manifolds via crystallizations and Heegaard diagrams

The idea of computing Matveev complexity by using Heegaard decompositions has been recently developed by two different approaches: the first one for closed 3-manifolds via crystallization theory, yielding the notion of Gem-Matveev complexity; the other one for compact orientable 3-manifolds via generalized Heegaard diagrams, yielding the notion of modified Heegaard complexity. In this paper we extend to the non-orientable case the definition of modified Heegaard complexity and prove that for closed 3-manifolds Gem-Matveev complexity and modified Heegaard complexity coincide. Hence, they turn out to be useful different tools to compute the same upper bound for Matveev complexity.Comment: 12 pages; accepted for publication in Topology and Its Applications, volume containing Proceedings of Prague Toposym 201

The notion of "economic area" by Carlos Sempat Assadourian and its possiblity of usage in regional histories of different places and times

Este trabajo retoma la preocupación planteada por Carlos Sempat Assadourian en la década de 1970 sobre la necesidad de recuperar la noción de “espacio económico” frente a las limitaciones que ofrecían para el análisis empírico los recortes territoriales, basados tanto en los ámbitos nacionales como en los locales, unos por demasiado homogeneizadores y otros por excesivamente pequeños. Sus novedosos planteos sobre la naturaleza del sistema colonial tomaban como base la definición de un “espacio económico peruano”, que no reconocía los límites territoriales impuestos. El análisis de este por demás dinámico mercado interno colonial, le permitía observar a Assadourian un proceso histórico de integración y desintegración regional donde las formas socioeconómicas sorprendían por su larga duración y donde los factores historiográficamente analizados hasta allí como “externos”, se transformaban comprensivamente en elementos “internos” a la región misma. Este significativo aporte para la conceptualización regional fue escasamente utilizado por la historiografía argentina hasta después de la década de 1980, cuando quienes intentaban estudiar espacios regionales avanzado el siglo XIX buscaban la manera de aportar a una historia nacional demasiado generalizante, inscribiendo sus objetos de estudios en contextos lo suficientemente amplios como para permitirles conservar su especificidad y dinámica interna, volviéndolos a la vez operativamente comparables con el conjunto nacional e internacional vigentes.This work takes the concerns raised by Carlos Sempat Assadourian in the 1970s about the need to recover the notion of "economic space" from the constraints offered for empirical analysis by the territorial cuts, based both at the national and in the local, one for be too homogeneous and the other for too small. Its innovative approaches to the nature of the colonial system took as a basis the definition of a "Peruvian economic space", which did not recognize the territorial limits imposed. The analysis of this by far dynamic colonial inner market, allowed to Assadourian to observe a historical process of regional integration and disintegration where socioeconomic forms surprised by its long duration and where the factors analyzed historiographically there as "external", was sympathetically transformed into elements "internal" to the region itself. This significant contribution to the regional conceptualization was little used by historians Argentina until the 1980s, when those who were trying to study regional areas into the nineteenth century, were seeking to contribute to a national history too generalizing, registering their objects of study contexts broad enough to enable to retain its specific and internal dynamics, making them both operationally comparable with all national and international regulations.Fil: Bandieri, Susana Ofelia. Unidades En Red - Conicet. Investigaciones Socio-historicas Regionales. Centro de Estudios de Historia Regional - Nodo Cehir - Ishir; Argentin

Business families in Southern Patagonia: from the end of the 19th Century to the first decades of 20th century

The groups of settlers who arrived in Punta Arenas in Southern Patagonia in the second half of the 19th century, established the trade in hunting products, leather and exotic feathers. They organized the first companies as trading houses between individuals and friends. The capital accumulation of these immigrants promoted take-off and productive control based on external trade routes, an evidence of prior connections abroad. From 1881, the multiplication of some family companies boosted out controlling branches and suppliers of value productive chains through different association to foreign groups encouraged by the offer of land concessions. Partnership by friendship and family also added anonymous societies with a shareholder scheme including family members. The major article’s goal is to analyze first family business in this context, through a genealogy business approach. Theoretical concepts and method used here include debates of economic history and entrepreneurial history focused on family business. The core is social and commercial structures for understanding the family continuity, and also business survival in specific contexts. We elaborate three intertwined commercial and family genealogies that worked first in Punta Arenas before 1908 and later in Argentina. And, we analyze strategies by family members of second and third generations achieved for survival, and configuration of the Braun-Menéndez Behety business family. We relate some findings to the connections between Punta Arenas economy and European capitalism; interregional connections; the family as a socio-cultural dimension in entrepreneurship; management innovations in rural contexts and the pathways followed to establish the firsts mother-firms in Austral Patagonian Area

Computing Matveev's complexity via crystallization theory: the boundary case

The notion of Gem-Matveev complexity has been introduced within crystallization theory, as a combinatorial method to estimate Matveev's complexity of closed 3-manifolds; it yielded upper bounds for interesting classes of such manifolds. In this paper we extend the definition to the case of non-empty boundary and prove that for each compact irreducible and boundary-irreducible 3-manifold it coincides with the modified Heegaard complexity introduced by Cattabriga, Mulazzani and Vesnin. Moreover, via Gem-Matveev complexity, we obtain an estimation of Matveev's complexity for all Seifert 3-manifolds with base $\mathbb D^2$ and two exceptional fibers and, therefore, for all torus knot complements.Comment: 27 pages, 14 figure

The competitiveness of Romagna wineries. An exploratory analysis of the 6 impact of different strategic approaches on business performance

This paper proposes an exploratory study of the competitiveness of Romagna wineries. A double approach has been adopted to analyse it, as both Porter's Theory of Competitive Advantage and Barney's Resource-based Theory have been considered. The final purposes are to uncover which categories of resources and capabilities are related to firm performance and to investigate the main strategic orientations of the most successful Romagna wineries. To conduct the research, an online questionnaire was sent to 115 wineries located in the Romagna territory, achieving a response rate of about 24.35%. According to the preliminary results, it has been found that the most successful wineries in this area do not follow a cost leadership strategy, while they perform a differentiation strategy. These firms put a lot of effort into building a reputation in the market. On the other hand, managerial and technological capabilities seem to be not positively related to firm performance, while marketing capabilities exert a stronger impact. This study would give an input to the strategic and managerial studies in the wine business sector, and adopt an innovative theoretical approach in the analysis of competitive advantage. Moreover, this work focuses on the Romagna territory, fulfilling the need for research that considers the local wine industry and its competitiveness, to open the way to further studies