706 research outputs found
Progetto, modello e messaggio rivoluzionario. L'opera di Tommaso Campanella tra Utopismo e Realismo
Una rilettura delle principali opere di Tommaso Campanella
nella cornice storico – culturale del Rinascimento
e un confronto linguistico e tematico con il testo de
Il principe di Niccolò Machiavelli può porre sotto una
diversa luce la tradizionale distinzione tra filosofia utopistica
e realista, per tentar di abbandonare distinzioni
interpretative spesso fuorvianti
Demystifying Emergence:A New Exploration Through Scientific Case Studies
In this thesis I argue that a modified version of Jessica Wilson’s subset view, what I call the Holistically Defined Modal view, is the most promising nonreductive physicalist account to accommodate not only mental causation but also other kinds of higher-level causation. In this thesis I do not endeavour to demonstrate nonreductive physicalism’s superiority against competitors, such as reductive physicalism or strong emergence. Rather, my goal is to investigate how nonreductive physicalism should be spelled out assessing what I consider the most interesting and successful candidates for the best nonreductive physicalist account. The three candidates are Jessica Wilson’s subset view, Sydney Shoemaker’s mereological version of the subset view, and Carl Gillett’s mutualism.In Chapter 1, I first provide historical context to the concept of emergence, and I explain its interpretation within this thesis to disambiguate it from alternative definitions or uses. I then introduce Jaegwon Kim’s Causal Exclusion Argument, which is one of the most potentially damning and recurrent objections against nonreductive physicalism. In Chapter 2, I present the subset view as well as Wilson’s response to Kim’s argument. The subset view proposes that for higher-level properties to be causally efficacious in a significant way it is sufficient that they have a distinct set of powers (or causal profile) vis-à-vis their realisers. In this chapter I also defend the subset view against Sara Bernstein’s version of Kim’s objection.In Chapter 3 I present Shoemaker’s version of the subset view and conclude that Wilson’s account is superior to it. In Chapter 4 I introduce Gillett’s account, as well as Gillett’s Problem of Qualitative Distinctness against the subset view. Gillett claims that science explains the behaviour of special science entities in terms of the joint behaviour of their constituents. From this claim he builds an argument to show that special science properties of composites are realised by the properties of its constituents, which leads him to conclude that properties at different levels do not share any powers ––i.e., they are qualitatively distinct. That claim is a direct threat to the subset view, which requires power sharing, and according to Gillett it makes it an untenable view.To assess Gillett’s objection, I focus on whether realisation is a many-to-one relation – what I refer to as realisationM-O – or a one-to-one relation – realisationO-O. Gillett argues that it must be many-to-one, given that this is the only way to preserve qualitative distinctness between realiser and realisee. Wilson’s way to deal with the apparent many-to-one nature of realisation of special science properties is to provide an ontologically lightweight structural property that bridges the many properties of constituents and the higher-level realised property of the composite. She refers to this kind of properties as “middleman properties”. In the last section of Chapter 4 I argue that Wilson has not provided a successful response to Gillett’s threat, and that the existence of middleman properties is not properly justified. The chapter, therefore, is inconclusive as to whether realisation has a one-to-one or many-to-one structure. Chapter 5 serves as a linking chapter, emphasizing the importance of case studies in elucidating the nature of realisation and discussing their treatment in Wilson’s and Gillett’s works. Chapters 6 and 7 present two scientific case studies and assess whether any of the two kinds of realisation, realisationM-O or realisationO-O, can account for them.In Chapter 6, I explain how statistical mechanics derives and defines entropy, which is a property of thermodynamic systems from the properties of the particles composing the systems. In Chapter 7, I explain how one of the most influential scientific theories of consciousness, the Global Neuronal Workspace Theory, explains how conscious states arise from brain states.This thesis concludes that the realisation relation that accounts for both the realisation of entropy and conscious properties is realisationO-O, whereas realisationM-O can, at best, only partially account for them. Hence, realisationO-O is the most general account of realisation. This conclusion is based on one main finding: in both case studies there are scientific grounds to accept the genuine existence of middleman properties. However, the case studies also unveil that Wilson’s definition of “middleman property” –and thus her view– needs to be substantially modified. In Chapters 6 and 7 I present and discuss the modified version of the subset view: the Holistically Defined Modal view –the HDM view. According to this view, a realiser is a holistically defined modal property. I define both the modal aspect and the holistic aspect of the view in a broad sense, that also encompasses cases where a narrow definition applies. The holistic aspect of the view entails that the realiser is defined in terms of properties and states of the system, where those properties and states of the system might or might not be further defined in terms of compositional principles and Boolean operations on its constituents. The modal aspect of the view entails that the realiser has a modal aspect, namely, it considers possible states the system could be in. In a broad sense, there are cases where the only possible states of the system considered are actual states, which nonetheless are possible states of the system. The Entropy Case Study is an example of a realiser that is a holistically defined modal property in a narrow sense for both aspects, whereas the Neuronal Global Workspace presents an example of a realiser that is holistically defined in a narrow sense and is modal in a broad sense.<br/
Algae Culture Conditions and Process Parameters for Phycoremediation and Biomaterials Production
Abstract
Climate change and increasing world population call for careful utilization of water and energy sources. Microalgae to treat wastewater in a coupled process to produce biofuels and other value-added products for human consumption are promising solutions. An analysis of culture parameters and cultivation processes is presented as essential to achieve economical sustainability from the algae. Results of the activity of microalgal strains in detoxification of wastewater are compared and discussed, particularly in remediation of nitrogen and phosphorous compounds, heavy metal, pharmaceuticals and personal care products. Phycoremediation mechanisms and culture conditions to obtain optimal microalgal growth are discussed. Finally, valuable products that can be produced by microalgae and ecological problems of untreated wastewater are presented
Variabilidad espacial en determinaciones de carbono, nitrógeno, fósforo y ph, de un muestreo sistemático de suelo
p.43-48En una unidad taxonómica planosol somero, se realizó un muestreo sistemático tridimensional. Se obtuvieron 100 muestras en una cuadrícula diseñada sobre una hectárea. En el ensayo se incorporaron dos fuentes de variabilidad: a) distinta profundidad, b) distintos manejos. Sobre ellos se realizaron las determinaciones de carbono total, nitrógeno total, fósforo asimilable, pH actual y pH potencial. En todos los casos se describe la población a través de su media muestral, varianza y coeficiente de variación. Con estos datos se calcula el número mínimo de muestras a extraer, para un error permitido de hasta el 15 por ciento de su media. Los datos fueron analizados estadísticamente, comprobándose que el carbono y nitrógeno presentan diferencias altamente significativas al muestrearse en las dos profundidades propuestas en el ensayo. En fósforo se encontraron diferencias altamente significativas tanto en las distintas profundidades como manejos. En pH actual y potencial hay igualdad de datos para las variables seleccionadas. Se concluye que para que un muestreo resulte representativo de un área y los resultados obtenidos tengan un mínimo de seguridad, deberán tenerse en cuenta los siguientes aspectos: la profundidad de muestreo, el manejo dado al suelo y la característica del elemento a medir
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Elevated numbers of PD-L1 expressing B cells are associated with the development of AIDS-NHL.
The risk for non-Hodgkin lymphoma (NHL) is markedly increased in persons living with human immunodeficiency virus (HIV) infection, and remains elevated in those on anti-retroviral therapy (cART). Both the loss of immunoregulation of Epstein-Barr virus (EBV) infected cells, as well as chronic B-cell activation, are believed to contribute to the genesis of AIDS-related NHL (AIDS-NHL). However, the mechanisms that lead to AIDS-NHL have not been completely defined. A subset of B cells that is characterized by the secretion of IL10, as well as the expression of the programmed cell death ligand-1 (PD-L1/CD274), was recently described. These PD-L1+ B cells can exert regulatory function, including the dampening of T-cell activation, by interacting with the program cell death protein (PD1) on target cells. The role of PD-L1+ B cells in the development of AIDS-NHL has not been explored. We assessed B cell PD-L1 expression on B cells preceding AIDS-NHL diagnosis in a nested case-control study of HIV+ subjects who went on to develop AIDS-NHL, as well as HIV+ subjects who did not, using multi-color flow cytometry. Archival frozen viable PBMC were obtained from the UCLA Multicenter AIDS Cohort Study (MACS). It was seen that the number of CD19+CD24++CD38++and CD19+PD-L1+cells was significantly elevated in cases 1-4 years prior to AIDS-NHL diagnosis, compared to controls, raising the possibility that these cells may play a role in the etiology of AIDS-NHL. Interestingly, most PD-L1+ expression on CD19+ cells was seen on CD19+CD24++CD38++ cells. In addition, we showed that HIV can directly induce PD-L1 expression on B cells through interaction of virion-associated CD40L with CD40 on B cells
Cuarenta años de degradación de argiudoles vérticos en la provincia de Entre Ríos
In the last decade the land use in Entre Ríos Province (Argentina) has suffered a very important increase characterized by an intensive and continuous agriculture in a region with high water erosion susceptibility. Forty percent of province surface suffers water erosion in different degrees. This study was undertaken to assess the extent and nature of degradation in some physical and chemical properties of vertic Argiudolls through the comparison of a pristine situation and three situations with increasing years of land use after deforestation. Organic carbon (OC), light carbon (LC), pH, electrical conductivity (EC), labile organic phosphorus (Plo), structural stability (∆MWD), size aggregate distribution in the A horizon were determined. After 40 years from deforestation the OC, LC, Plo, decreased 26, 72 and 17% respectively meanwhile EC and pH had minor variations. The structural stability declined with time and there was a significant correlation between organic carbon and ∆MWD (r = - 0.985; P < 0.02; n = 4). Sixty two percent of the A-horizon was lost and as a consequence, 75.5% in carbon sequestration. A mean annual erosion rate of 60 Mg ha-1 yr-1 after 40 years was estimated.En la última década el uso de la tierra en la provincia de Entre Ríos (Argentina) ha sufrido un incremento muy importante basado en la agricultura contínua e intensiva en una región con alta susceptibilidad de erosión hídrica. Cuarenta por ciento de la superficie de la Provincia posee erosión hídrica de diferentes grados de severidad. Este trabajo fue llevado a cabo para examinar el grado y la naturaleza de la degradación en algunas propiedades físicas y químicas en suelos vérticos a través de la comparación de una situación prístina con tres situaciones con diferentes años de agricultura luego de su deforestación. El carbono orgánico (OC), carbono liviano (LC), pH, conductividad eléctrica (EC), fósforo orgánico lábil (Plo), estabilidad estructural (∆MWD) y la distribución del tamaño de agregados en el horizonte A fueron determinados. Luego de 40 años de la deforestación el OC, LC y el Plo, disminuyeron 26, 72 y 17% respectivamente, comparados con la situación prístina mientras que la EC y el pH tuvieron sólo variaciones menores. La estabilidad de los agregados disminuyó con el tiempo y hubo una correlación significativa entre el OC y ∆MWD (r = - 0,985; P < 0,02; n = 4). Sesenta y dos por ciento de la profundidad del horizonte A fue erosionada y, como consecuencia, el 75,5% del carbono secuestrado originalmente fue perdido. Fue estimada una tasa de erosión anual promedio de 60 Mg ha-1 año-1 luego de 40 años.Fil: Cosentino, Diego. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Conti, Marta Elvira. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Giuffre, Lidia. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente; Argentin
Optical gain in DNA-DCM for lasing in photonic materials
We present a detailed study of the gain length in an active medium obtained
by doping of DNA strands with DCM dye molecules. The superior thermal stability
of the composite and its low quenching, permits to obtain optical gain
coefficient larger than 300 cm^-1. We also show that such an active material is
excellent for integration into photonic nano-structures, to achieve, for
example, efficient random lasing emission, and fluorescent photonic crystals
Roads to Innovation: Evidence from Italy
In this study, we leverage on the ancient Roman roads network as a source of exogenous variation to identify the causal effect of the modern highways network on innovative performance of Italian NUTS\u20103 regions. Empirical findings suggest that a 10% increase in the highways stock in a region generates an increase in the number of patents of about 3%\u20134%, over a 5\u2010year period. Further analysis suggests that our findings can in part be explained by a reduction in travel costs that fosters collaborations among inventors living in different regions and by an increase in the degree of centrality in the regional innovation network associated to denser highways networks. Finally, we find that the innovation\u2010enhancing effect of highways declines over time, possibly because of the introduction of information and communication technology, or the increasing congestion on the Italian network
Variaciones de nitrógeno liviano y nitratos producidos por los distintos manejos del cultivo de maíz en suelos argiudoles
p.335-343En suelos argiudoles de la provincia de Buenos Aires, se realizaron distintos ensayos para cuantificar el ritmo de mineralización del nitrógeno liviano y la producción de nitratos obtenida. Las variables usadas fueron diferentes manejos sobre un cultivo de maíz, sistemas de labranza y fertilización. El orden de la mineralización del nitrógeno liviano al finalizar el ciclo vegetal sigue la tendencia general de arada con cincel menos que arada con reja y ésta menos que arada de desfonde. En nitratos se evidencia un comportamiento similar en los diferentes manejos y lugares, con máximos de producción en septiembre-octubre y bruscas disminuciones en diciembre. El agregado de fertilizante (UREA) tiene influencia disminuyendo la mineralización de nitrógeno liviano y aumentando la producción de nitratos
Multivariate evaluation by quality indicators of no-tillage system in Argiudolls of rolling pampa (Argentina)
The purpose of this study was to develop operationally important soil quality indicators to evaluate long-term sustainability, at the farm scale, for no-tillage systems in Argiudolls of rolling pampa (Argentina). The soil was classified as series Arroyo Dulce (Typic Argiudoll), a fertile dark, deep and well-drained soil of the hills. Three situations were considered: pristine soil with grass vegetation, grassland soil (also considered as a reference situation); and 15 years no-tillage soils from four production plots. Physical, physico-chemical, chemical and biochemical indicators were considered. Data were analyzed by principal components analysis (PCA) with canonical discriminant analysis (CDA). The first three components explained 90% of the overall variation. For pristine undisturbed soil, the main variables selected by PCA were particulate C, pH, respiration and total organic C, and in the case of grassland they were C stock (mass of C in the 0-10 cm soil horizon), water-soluble C, and % silt. The no-tillage area was separated in different plots according to the degree of erosion with different depths of the A horizon. Clay content and bulk density were the main variables in the less degraded no tillage plots. Cluster analysis was applied to construct an average linkage distance dendrogram.Fil: Giuffre, Lidia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Edafología; ArgentinaFil: Romaniuk, Romina Ingrid. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Edafología; ArgentinaFil: Conti, Marta Elvira. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Edafología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario; ArgentinaFil: Bartoloni, Norberto Jose. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Métodos Cuantitativos y Sistemas de Información; Argentin
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