157 research outputs found
PERIODIZACIÓN Y PRAXIS PARA EL ESTUDIO DE LA CRÍTICA LITERARIA EN LAS PRINCIPALES PUBLICACIONES PERIÓDICAS Y CULTURALES DE SANTIAGO DE CUBA (1825-1895)
Como parte de uma investigação mais ampla, o artigo estabelece as bases para a periodização e prática do estudo da crítica literária nas principais publicações periódicas e culturais do século XIX em Santiago de Cuba. Primeiro, analisa os critérios periodológicos das referências mais reconhecidas sobre a exegese literária cubana do período colonial, depois estabelece a periodização para o estudo desta disciplina da ciência literária na segunda cidade mais importante das Antilhas Caribenhas. Posteriormente, cada uma das etapas referidas é caracterizada em detalhes, de acordo com as fontes bibliográficas regionais recuperadas para a investigação, enfatizando em suas singularidades com relação àquelas fixadas pelos paradigmas da historiografia da crítica literária cubana do século XIX. Finalmente, a periodização proposta é comparada com a articulada no cânone nacional. Este exercício metacrítico indica que os sistemas e processos literários dentro de um mesmo país, embora tenham aspectos comuns, geralmente não são sincrônicos em suas diferentes regiões.Palavras-chave: Crítica literária. Literatura cubana. Século XIX. Santiago de Cuba. Periódicos. Publicações culturaisResumen:Como parte de una investigación mayor, en el artículo se plantean las bases para la periodización y la praxis del estudio de la crítica literaria en las principales publicaciones periódicas y culturales del Santiago de Cuba decimonónico. Primeramente, se analizan los criterios periodológicos de las referencias más reconocidas sobre la exégesis literaria cubana de la etapa colonial, luego se establece la periodización para el estudio de dicha disciplina de la ciencia literaria en la segunda ciudad en importancia de la mayor de las Antillas caribeñas. Más adelante, se caracterizan pormenorizadamente cada una de lasetapas referidas, acorde con las fuentes bibliográficas regionales recuperadas para la investigación, enfatizando en sus singularidades respecto a las fijadas por los paradigmas de la historiografía de la crítica literaria cubana del siglo XIX. Finalmente, se compara la periodización propuesta respecto a la articulada en el canon nacional. Este ejercicio metacrítico muestra que los sistemas y procesos literarios dentro de un mismo país, aunque posean aspectos comunes, generalmente no son sincrónicos en sus diferentes regiones.Palabras claves: Crítica literaria. Literatura cubana. Siglo XIX. Santiago de Cuba. Publicaciones periódicas y culturalesAbstract:As part of a major research, the article raises the bases for the periodization andpraxis of the study of literary criticism in the main periodical and cultural publications of the 19th century’s Santiago de Cuba. First, the periodological criteria of the most recognized references on Cuban literary exegesis of the colonial period are analyzed, then it’s established the periodization for the study of this discipline of literary science in the second most important city of the Caribbean Antilles. Later on, each one of the referred stages is characterized in detail, according to the regional bibliographic sources recovered for the research, emphasizing in its singularities regarding the ones fixed by the paradigms of historiography of Cuban literary criticism in the 19th century. Finally, the periodization proposed is compared with the one articulated in the national canon. This meta-critical exercise reveals that literary systems and processes within the same country, although they have common aspects, generally are not synchronic in their different regions.Keywords: Literary criticism. Cuban literature. 19th century. Santiago de Cuba. Periodicals and cultural publication
Health Hazard from Gas Emissions in the Quaternary Volcanic Province of Latium (Italy)
The Quaternary Volcanic Province of Central Italy is characterized by zones with a huge endogenous degassing where frequent, sometimes lethal, accidents occur to people and animals. The emitted gas has a deep origin (volcanic or mantle) and is mainly composed by CO2 (up to 98%) and H2S (1-4%), which may reach dangerous concentrations both in open air and indoor. Here we present the results of a multiparametric geochemical study carried out in 2007-2009 in the Provinces of Rome and Viterbo (Latium), with the aim of assessing the health hazard of their main gas emission sites (GES). Three types of GES were investigated: 1. natural, open-air thermal pools, 2. within natural reserves, 3. near to inhabited zones. More than 15 GES have been studied, and here we will illustrate some of the cases with the highest hazard. Results are presented for the sites of Vejano and Mola di Oriolo (Viterbo), Caldara di Manziana, Tor Caldara and Solforata di Pomezia (Rome). Cava dei Selci is a well-known inhabited area of the volcanic complex of Colli Albani (Rome). In each site, multi-technique surveys have been carried out to estimate the total gas output and its concentration in air, by measuring: CO2 and H2S viscous and diffuse flux (the latter by accumulation chamber), CO2 and H2S concentration in air (by TDL profiles and punctual Draeger measurements); moreover, the chemical and isotopic composition of the gas was determined in each site. In all these zones, lethal air concentrations may be reached by both H2S and CO2, but more frequently by the first. Recommendations for risk reduction were given to Civil Protection authorities.Comission of Cities and Volcanoes (CaV) of the International Association of Volcanology and Chemistry of the Earth's Interior (IAVCEI) Agencia Española de Cooperación Internacional para el Desarrollo (AECID), Gobierno de España Ministerio de Ciencia e Innovación (MICINN), Gobierno de España
Unidad Militar de Emergencias (UME), Ministerio de Defensa, Gobierno de España
Agencia Canaria de Investigación, Innovación y Sociedad de la Información (ACIISI), Gobierno de Canarias Viceconsejería de Infraestructuras y Planificación, Gobierno de Canarias Consejería de Turismo, Gobierno de Canarias Consejería de Medio Ambiente y Ordenación Territorial, Gobierno de Canarias
Viceconsejería de Cultura y Deportes, Gobierno de Canarias Instituto Español de Oceanografía (IEO)Instituto Geológico y Minero de España (IGME)Instituto Geográfico Nacional (IGN)Academia Canaria de Seguridad
Federación Canaria de Municipios (FECAM)
Universidad de La Laguna (ULL)Instituto de Estudios Hispánicos de Canarias (IEHC)
CajaCanariasPublishedPuerto de la Cruz, Tenerife, Spain1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attive4.5. Studi sul degassamento naturale e sui gas petroliferiope
Hazardous gas emissions from the flanks of the quiescent Colli Albani volcano (Rome, Italy)
Gas hazard was evaluated in the three most important cold gas emission zones on the flanks of the quiescent Colli Albani volcano. These zones are located above structural highs of the buried carbonate basement which represents the main regional aquifer and the main reservoir for gas rising from depth. All extensional faults affecting the limestone reservoir represent leaking pathways along which gas rises to the surface and locally accumulates in shallow permeable horizons forming pressurized pockets that may produce gas blowout when reached by wells. The gas, mainly composed by CO2 (>90 vol.%), contains appreciable quantities of H2S (0.35-6 vol.%), and both represent a potentially high local hazard. Both gases are denser than air and accumulate near ground where they may reach hazardous concentrations, and actually lethal accidents frequently occur to animals watering at local ponds. In order to evaluate the rate of degassing and the related hazard, CO2 and H2S diffuse soil flux surveys have been repeatedly carried out by accumulation chamber. The viscous gas flux of some important discrete emissions has been also evaluated and the CO2 and H2S air concentration measured by portable devises and by Tunable Diode Laser profiles. The minimum potential lethal concentration of the two gases (250 ppm for H2S and 8 vol.% for CO2) is 320 times higher for CO2, whereas the CO2/H2S concentration ratio in the emitted natural gas is significantly lower (15-159). This explains why H2S reaches hazardous, even lethal, concentrations more frequently than CO2. A relevant hazard exists for both gases in the depressed zones (channels, excavations) particularly in the non-windy early hours of the day
Orchestration of Network Services Across Multiple Operators: The 5G Exchange Prototype
Future 5G networks will rely on the coordinated
allocation of compute, storage, and networking resources in
order to meet the functional requirements of 5G services as well
as guaranteeing efficient usage of the network infrastructure.
However, the 5G service provisioning paradigm will also require
a unified infrastructure service market that integrates multiple
operators and technologies. The 5G Exchange (5GEx) project,
building heavily on the Software-Defined Network (SDN) and the
Network Function Virtualization (NFV) functionalities, tries to
overcome this market and technology fragmentation by
designing, implementing, and testing a multi-domain
orchestrator (MdO) prototype for fast and automated Network
Service (NS) provisioning over multiple-technologies and
spanning across multiple operators. This paper presents a first
implementation of the 5GEx MdO prototype obtained by
extending existing open source software tools at the disposal of
the 5GEx partners. The main functions of the 5GEx MdO
prototype are showcased by demonstrating how it is possible to
create and deploy NSs in the context of a Slice as a Service
(SlaaS) use-case, based on a multi-operator scenario. The 5GEx
MdO prototype performance is experimentally evaluated
running validation tests within the 5GEx sandbox. The overall
time required for the NS deployment has been evaluated
considering NSs deployed across two operators
Pro-Inflammatory CD11c+CD206+ Adipose Tissue Macrophages Are Associated With Insulin Resistance in Human Obesity
OBJECTIVE: Insulin resistance and other features of the metabolic syndrome have been causally linked to adipose tissue macrophages (ATMs) in mice with diet-induced obesity. We aimed to characterize macrophage phenotype and function in human subcutaneous and omental adipose tissue in relation to insulin resistance in obesity. RESEARCH DESIGN AND METHODS: Adipose tissue was obtained from lean and obese women undergoing bariatric surgery. Metabolic markers were measured in fasting serum and ATMs characterized by immunohistology, flow cytometry, and tissue culture studies. RESULTS ATMs comprised CD11c(+)CD206(+) cells in "crown" aggregates and solitary CD11c(-)CD206(+) cells at adipocyte junctions. In obese women, CD11c(+) ATM density was greater in subcutaneous than omental adipose tissue and correlated with markers of insulin resistance. CD11c(+) ATMs were distinguished by high expression of integrins and antigen presentation molecules; interleukin (IL)-1beta, -6, -8, and -10; tumor necrosis factor-alpha; and CC chemokine ligand-3, indicative of an activated, proinflammatory state. In addition, CD11c(+) ATMs were enriched for mitochondria and for RNA transcripts encoding mitochondrial, proteasomal, and lysosomal proteins, fatty acid metabolism enzymes, and T-cell chemoattractants, whereas CD11c(-) ATMs were enriched for transcripts involved in tissue maintenance and repair. Tissue culture medium conditioned by CD11c(+) ATMs, but not CD11c(-) ATMs or other stromovascular cells, impaired insulin-stimulated glucose uptake by human adipocytes. CONCLUSIONS: These findings identify proinflammatory CD11c(+) ATMs as markers of insulin resistance in human obesity. In addition, the machinery of CD11c(+) ATMs indicates they metabolize lipid and may initiate adaptive immune responses
Partial Oxidation of Methane to Syngas Over Nickel-Based Catalysts: Influence of Support Type, Addition of Rhodium, and Preparation Method
There is great economic incentive in developing efficient catalysts to produce hydrogen or syngas by catalytic partial oxidation of methane (CPOM) since this is a much less energy-intensive reaction than the highly endothermic methane steam reforming reaction, which is the prominent reaction in industry. Herein, we report the catalytic behavior of nickel-based catalysts supported on different oxide substrates (Al2O3, CeO2, La2O3, MgO, and ZrO2) synthesized via wet impregnation and solid-state reaction. Furthermore, the impact of Rh doping was investigated. The catalysts have been characterized by X-ray diffraction, N2 adsorptiondesorption at −196°C, temperature-programmed reduction, X-ray photoelectron spectroscopy, O2-pulse chemisorption, transmission electron microscopy, and Raman spectroscopy. Supported Ni catalysts were found to be active for CPOM but can suffer from fast deactivation caused by the formation of carbon deposits as well as via the sintering of Ni nanoparticles (NPs). It has been found that the presence of Rh favors nickel reduction, which leads to an increase in the methane conversion and yield. For both synthesis methods, the catalysts supported on alumina and ceria show the best performance. This could be explained by the higher surface area of the Ni NPs on the alumina surface and presence of oxygen vacancies in the CeO2 lattice, which favor the proportion of oxygen adsorbed on defect sites. The catalysts supported on MgO suffer quick deactivation due to formation of a NiO/MgO solid solution, which is not reducible under the reaction conditions. The low level of carbon formation over the catalysts supported on La2O3 is ascribed to the very high dispersion of the nickel NPs and to the formation of lanthanum oxycarbonate, through which carbon deposits are gasified. The catalytic behavior for catalysts with ZrO2 as support depends on the synthesis method; however, in both cases, the catalysts undergo deactivation by carbon deposits
The role of sex separation in neutral speciation
Neutral speciation mechanisms based on isolation by distance and sexual
selection, termed topopatric, have recently been shown to describe the observed
patterns of abundance distributions and species-area relationships. Previous
works have considered this type of process only in the context of hermaphrodic
populations. In this work we extend a hermaphroditic model of topopatric
speciation to populations where individuals are explicitly separated into males
and females. We show that for a particular carrying capacity speciation occurs
under similar conditions, but the number of species generated decreases as
compared to the hermaphroditic case. Evolution results in fewer species having
more abundant populations.Comment: 18 pages + 8 figure
Spatio-Temporal Credit Assignment in Neuronal Population Learning
In learning from trial and error, animals need to relate behavioral decisions to environmental reinforcement even though it may be difficult to assign credit to a particular decision when outcomes are uncertain or subject to delays. When considering the biophysical basis of learning, the credit-assignment problem is compounded because the behavioral decisions themselves result from the spatio-temporal aggregation of many synaptic releases. We present a model of plasticity induction for reinforcement learning in a population of leaky integrate and fire neurons which is based on a cascade of synaptic memory traces. Each synaptic cascade correlates presynaptic input first with postsynaptic events, next with the behavioral decisions and finally with external reinforcement. For operant conditioning, learning succeeds even when reinforcement is delivered with a delay so large that temporal contiguity between decision and pertinent reward is lost due to intervening decisions which are themselves subject to delayed reinforcement. This shows that the model provides a viable mechanism for temporal credit assignment. Further, learning speeds up with increasing population size, so the plasticity cascade simultaneously addresses the spatial problem of assigning credit to synapses in different population neurons. Simulations on other tasks, such as sequential decision making, serve to contrast the performance of the proposed scheme to that of temporal difference-based learning. We argue that, due to their comparative robustness, synaptic plasticity cascades are attractive basic models of reinforcement learning in the brain
Anti- Japanese-Encephalitis-Viral Effects of Kaempferol and Daidzin and Their RNA-Binding Characteristics
Background: New therapeutic tools and molecular targets are needed for treatment of Japanese encephalitis virus (JEV) infections. JEV requires an a-1 translational frameshift to synthesize the NS1 ’ protein required for viral neuroinvasiveness. Several flavonoids have been shown to possess antiviral activity in vitro against a wide spectrum of viruses. To date, the antiviral activities of flavonol kaempferol (Kae) and isoflavonoid daidzin (Dai) against JEV have not been described. Methodology/Principal Findings: The 50 % cytotoxic concentration (CC50) and 50 % effective concentration (EC50) against JEV were investigated in BHK21 cells by MTS reduction. Activity against viral genomic RNA and proteins was measured by real-time RT-PCR and western blotting. The frameshift site RNA-binding characterization was also determined by electrospray ionization mass spectrometry, isothermal titration calorimetry and autodocking analysis. EC 50 values of Kae and Dai were 12.6 and 25.9 mM against JEV in cells pretreated before infection, whereas in cells infected before treatment, EC50 was 21.5 and 40.4 mM, respectively. Kae exhibited more potent activity against JEV and RNA binding in cells following internalization through direct inhibition of viral replication and protein expression, indicating that its antiviral activity was principally due to direct virucidal effects. The JEV frameshift site RNA (fsRNA) was selected as a target for assaying Kae and Dai. ITC of fsRNA revealed an apparent Kb value for Kae that was nine fold stronger than that for Dai. This binding was confirmed and localized to the RNA using ESI-MS and autodock analysis. Kae could form non-covalent complexes wit
Glutathione Restores the Mechanism of Synaptic Plasticity in Aged Mice to That of the Adult
Glutathione (GSH), the major endogenous antioxidant produced by cells, can modulate the activity of N-methyl-D-aspartate receptors (NMDARs) through its reducing functions. During aging, an increase in oxidative stress leads to decreased levels of GSH in the brain. Concurrently, aging is characterized by calcium dysregulation, thought to underlie impairments in hippocampal NMDAR-dependent long-term potentiation (LTP), a form of synaptic plasticity thought to represent a cellular model for memory
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