1,615 research outputs found
Contrapunteos de Lydia Cabrera
No full textEven today in the history of Cuban anthropology, little attention is paid to the writer and anthropologist Lydia Cabrera, who has only recently begun to be part of the list of intellectuals in official Cuban culture. However, because of her work and life trajectory, Cabrera can be considered the modern founder of studies on Afro-Cuban religions.
The main purpose of this text is to analyse Lydia Cabrera’s ethnographic work based on the idea that there was a ‘counterpoint’, a dialogue, a metaphorical game, between the liminal identity of the author herself – manifested in a racial, cultural, gender, social and political sense – and her interest and dedication to the contribution of slaves and the population of African origin to the history, culture and, ultimately, the identity of their Cuban homeland.Todavía hoy en la historia de la antropología cubana se presta poca atención a la escritora y antropóloga Lydia Cabrera, quien solo muy recientemente ha empezado a formar parte de la nómina intelectual de la cultura cubana oficial. Sin embargo, en función de su obra y trayectoria vital puede considerarse a Cabrera como la fundadora moderna de los estudios sobre las religiones afrocubanas.
El objeto central de este texto es analizar el trabajo etnográfico de Lydia Cabrera a partir de la idea de que existe un contrapunteo, un diálogo, un juego metafórico, entre la identidad liminar de la propia autora -manifiesta en un sentido racial, cultural, de género, social y político- y su interés y dedicación a la aportación de los esclavos y la población de origen africano a la historia, a la cultura y, en última instancia, a la identidad misma de su patria cubana
Anomalous buoyancy of quantum bubbles in immiscible Bose mixtures
No full textBuoyancy is a well-known effect in immiscible binary Bose-Einstein
condensates. Depending on the differential confinement experienced by the two
components, a bubble of one component sitting at the center of the other
eventually floats to the surface, around which it spreads either totally or
partially. We discuss how quantum fluctuations may significantly change the
volume and position of immiscible bubbles. We consider the particular case of
two miscible components, forming a pseudo-scalar bubble condensate with
enhanced quantum fluctuations (quantum bubble), immersed in a bath provided by
a third component, with which they are immiscible. We show that in such a
peculiar effective binary mixture, quantum fluctuations change the equilibrium
of pressures that define the bubble volume and modify as well the criterion for
buoyancy. Once buoyancy sets in, in contrast to the mean-field case, quantum
fluctuations may place the bubble at an intermediate position between the
center and the surface. At the surface, the quantum bubble may transition into
a floating self-bound droplet.Comment: 8 pages, 5 figure
sj-docx-1-tai-10.1177_20499361241242963 – Supplemental material for Fungal infections in patients after recovering from COVID-19: a systematic review
No full textSupplemental material, sj-docx-1-tai-10.1177_20499361241242963 for Fungal infections in patients after recovering from COVID-19: a systematic review by Juan R. Ulloque-Badaracco, Cesar Copaja-Corzo, Enrique A. Hernandez-Bustamante, Juan C. Cabrera-Guzmán, Miguel A. Huayta-Cortez, Ximena L. Carballo-Tello, Rosa A. Seminario-Amez, Miguel Hueda-Zavaleta and Vicente A. Benites-Zapata in Therapeutic Advances in Infectious Disease</p
Xirú e “Abaporu” de Damián Cabrera: configurações do “comum” da comunidade / Xirú and “Abaporu” by Damián Cabrera: Community “Common” Settings
No full textResumo: O estudo discute o “comum” (ESPOSITO, 2012; NANCY, 2000) a partir do livro Xirú e do conto “Aboporu” de Damián Cabrera, autor cuja escrita encontra-se pautada nas relações Brasil-Paraguai. Nestas obras estão colocadas em evidência a crise de uma concepção essencialista de comunidade, dada e/ou determinada previamente e o distanciamento do “paradigma moderno imunitário” (ESPOSITO, 2012) que se impõe contra qualquer convivência ou contágio que afete a pretensa pureza da comunidade. Sendo a língua um elemento inerente ao pensamento comunitário, parte-se, também, de certa perspectiva “translingue” (MELLO & ANDRADE, 2019) utilizada pelo autor e que expõe os contatos entre as línguas e as interferências como continuum naturais, transitórios, imprevistos que se articulam nas relações entre estas culturas e não como substâncias dadas previamente.Não menos importante, neste sentido, é a antropofagia manifesta no conto “Abaporu”, uma antropofagia nada ufanista pois, como a perspectiva “translingue” que manifesta Xirú, não é identitária e sim, como têm apontado as leituras contemporâneas que dela fazem Alexandre Nodari (2011), Florencia Garramuño (2019) e Eduardo Sterzi (2017), uma antropofagia como experimentação da diversidade, e com ênfase em uma posição relacional. Desse modo, o “comum” nestas obras se constitui como aquilo que não é próprio à comunidade, como substâncias que se compartilham, mas como laço relacional.Palavras-chave: Damián Cabrera; comum; translinguismo; antropofagia.Abstract: The study discusses the “common” (ESPOSITO, 2012; NANCY, 2000) based on the book Xirú and the short story Aboporu by Damián Cabrera, an author whose writing is based on Brazil-Paraguay relations. These works highlight the crisis of an essentialist conception of community, given and/or determined in advance, and the distancing from the “immunitarian modern paradigm” (ESPOSITO, 2012) that imposes itself against any coexistence or contagion that affects the alleged purity of the community. Since language is an inherent element of community thinking, it also starts from a certain “translingual” perspective (MELLO & ANDRADE, 2019) used by the author and which exposes contacts between languages and interferences as a natural, transitory, unforeseen continuum that are articulated in the relations between these cultures and not as previously given substances. No less important, in this sense, is the anthropophagy manifested in the short story “Abaporu”, an anthropophagy that is far from boastful because, like the “translingual” perspective that manifests Xirú, it is not identity but, as pointed out by contemporary readings made by Alexandre Nodari (2011), Florencia Garramuño (2019) and Eduardo Sterzi (2017), an anthropophagy as an experimentation with diversity, and with an emphasis on a relational position. In this way, the “common” in these works is constituted as what is not proper to the community, as substances that are shared, but as a relational bond.Keywords: Damián Cabrera; common; translingual; anthropophagy
Synthesis and Characterization of Iridium(III) Complexes with Substituted Phenylimidazo(4,5-f)1,10-phenanthroline Ancillary Ligands and Their Application in LEC Devices
No full textIn this work, we report on the synthesis and characterization of six new iridium(III) complexes of the type [Ir(C^N)2(N^N)]+ using 2-phenylpyridine (C1–3) and its fluorinated derivative (C4–6) as cyclometalating ligands (C^N) and R-phenylimidazo(4,5-f)1,10-phenanthroline (R = H, CH3, F) as the ancillary ligand (N^N). These luminescent complexes have been fully characterized through optical and electrochemical studies. In solution, the C4–6 series exhibits quantum yields (Ф) twice as high as the C1–3 series, exceeding 60% in dichloromethane and where 3MLCT/3LLCT and 3LC emissions participate in the phenomenon. These complexes were employed in the active layer of light-emitting electrochemical cells (LECs). Device performance of maximum luminance values of up to 21.7 Lx at 14.7 V were observed for the C2 complex and long lifetimes for the C1–3 series. These values are counterintuitive to the quantum yields observed in solution. Thus, we established that the rigidity of the system and the structure of the solid matrix dramatically affect the electronic properties of the complex. This research contributes to understanding the effects of the modifications in the ancillary and cyclometalating ligands, the photophysics of the complexes, and their performance in LEC devices
Frustrated extended Bose-Hubbard model and deconfined quantum critical points with optical lattices at the anti-magic wavelength
No full textThe study of geometrically frustrated many-body quantum systems is of central importance to uncover novel quantum mechanical effects. We design a scheme where ultracold bosons trapped in a one-dimensional state-dependent optical lattice are modeled by a frustrated Bose-Hubbard Hamiltonian. A derivation of the Hamiltonian parameters based on Cesium atoms, further show large tunability of contact and nearest-neighbour interactions. For pure contact repulsion, we discover the presence of two phases peculiar to frustrated quantum magnets: the bond-order-wave insulator with broken inversion symmetry and a chiral superfluid. When the nearest-neighbour repulsion becomes sizeable, a further density-wave insulator with broken translational symmetry can appear. We show that the phase transition between the two spontaneously-symmetry-broken phases is continuous, thus representing a one-dimensional deconfined quantum critical point not captured by the Landau-Ginzburg-Wilson symmetry-breaking paradigm. Our results provide a solid ground to unveil the novel quantum physics induced by the interplay of non-local interactions, geometrical frustration, and quantum fluctuations.7+3 pages, 3+3 figure
Inteligência competitiva: uma proposta de implementação no setor elétrico
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção.Uma das características do modelo econômico da atualidade é o paradigma das tecnologias da informação, que estabelecem novas facilidades e possibilidades na distribuição da informação. O novo ambiente de negócio das empresas, apoiado na revolução das tecnologias da informação, é caracterizado pela velocidade das mudanças, pela conectividade manifestada na difusão da Internet e pela intangibilidade representada pelo conceito do capital intelectual da empresa. O debate sobre a construção das bases para uma sociedade da informação foi incorporado às agendas governamentais a partir dos anos 1990, partindo da concepção de que ela representa a transição do modelo de desenvolvimento industrial para o modelo baseado no conhecimento como insumo crítico. E as organizações orientadas por estratégias baseadas no conhecimento não podem prescindir do aporte da inteligência competitiva como ferramenta gerencial e executiva. Tendo como tema central a inteligência competitiva, o presente trabalho explora os elementos contextuais da atualidade, introduz o conceito da inteligência competitiva e apresenta exemplos de sua utilização por organizações de destaque no meio empresarial mundial. Passando por uma descrição das ferramentas de análise e da tecnologia da informação aplicáveis à inteligência competitiva, o trabalho chega ao seu objetivo geral, que é a proposição de implementação da função de inteligência competitiva numa empresa do setor elétrico. One of the fundamental characteristics of the current economic model is the paradigm of information technology, establishing new possibilities for information distribution. The new business environment supported by the revolution of information technology is characterized by the speed of changes, by the connectivity resulting from the spread of the Internet, and by the intangibility represented by the concept of intellectual capital of a company. The debate on the construction of the basis for a information society is part of governmental agenda since the beginning of last decade, considering that information society represents the transition from the industrial development model to the one based on knowledge as critical input. Organizations oriented by strategies based on knowledge cannot avoid the use of competitive intelligence as a managerial and executive tool. Taking competitive intelligence as central theme, the present dissertation explores the elements of the current world context, the concept of competitive intelligence is introduced, and examples are presented showing the use of competitive intelligence by important organizations of the global business sector. Competitive analysis and information technology tools applicable to competitive intelligence are described, and the general objective is attained with the proposition of implementing competitive intelligence in a company of the electricity sector
Consecuencias económicas de la minería en el municipio de La Jagua de Ibirico – Cesar
No full textEn Colombia la minería de carbón junto con el petróleo es una de las actividades que más ingresos le generan al país en materia de exportación. La mayoría de los proyectos mineros de carbón están a cargo de empresas Multinacionales ubicados en los departamentos del Cesar y la Guajira. Pero es en el Cesar donde más se explota este mineral. En La Jagua de Ibirico, municipio ubicado en pleno centro de las actividades mineras de carbón del Cesar es donde más ingresos se generan para el departamento y el país por concepto de regalías. Sin embargo, los altos ingresos por éstas no han podido ser reflejadas en una mejor calidad de vida de los pobladores ni en un desarrollo económico destacable. En este trabajo estableceremos un paralelo comparativo entre los ingresos obtenidos por la explotación del carbón y la calidad de vida de los habitantes del Cesar y La Jagua de Ibirico.In Colombia, coal mining, together with oil, is one of the activities that generates the most income for the country in terms of exports. Most of the coal mining projects are carried out by multinational companies located in the departments of Cesar and Guajira. But it is in Cesar where this mineral is most exploited. In La Jagua de Ibirico, a municipality located in the heart of the coal mining activities of Cesar is where most income is generated for the department and the country for the concept of royalties. However, the high incomes from these have not been reflected in a better quality of life for the inhabitants nor in a remarkable economic development. In this work we will establish a comparative parallel between the income obtained from coal mining and the quality of life of the inhabitants of Cesar and La Jagua de Ibirico.Economistahttps://www.ustabuca.edu.co/Pregrad
Desarrollo de superficies antimicrobianas a partir de la modificación de películas de polipropileno con sales de amonios cuaternarios
No full textTesis (Magister en Ciencias Químicas) - - Universidad Nacional de Córdoba. Facultad de Ciencias Químicas, 2023.Fil: Pastrana Cabrera, Luisa Fernanda. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.El tema de investigación de esta tesis se enfocó en el desarrollo de una superficie activa que contiene grupos arilamonios cuaternarios (PYR) injertados a cadenas de quitosano (Qs), que le brindan actividad antimicrobiana. Estos derivados de Qs se adsorbieron mediante interacción electrostática sobre la superficie de una película de polipropileno (PP) modificada en un 2 % p/p con ácido poliacrílico (PAA). En primera instancia, se sintetizaron una familia de sales de arilamonio cuaternario, tales como bromuro de 4-bromobutil-piridinio (PYR0), bromuro de 4-bromobutil-2- metilpiridinio (PYR1) y bromuro de 4-bromobutil-2,4-dimetilpiridinio (PYR2), a partir de la reacción de sustitución nucleofílica bimolecular entre el átomo de N del anillo y uno de los extremos terminales (-CH 2 Br) de 1,4-dibromobutano. Después de evaluar el efecto del solvente, temperatura y tiempo de reacción, se obtuvo un rendimiento de reacción cercano al 75 % en el siguiente orden decreciente: PYR2>PYR1>PYR0. Posteriormente, estas sales se injertaron covalentemente en cadenas Qs, con un rendimiento cercano al 73 %, a partir de la reacción de sustitución entre la terminal halogenada de PYR y el grupo amino de Qs. Los derivados Qs-PYR se adsorbieron sobre la superficie de las películas de PP-PAA mediante interacciones electrostáticas con los grupos carboxilos y aminos de Qs, alcanzando un grado de inmovilización promedio cercano al 1,7 % p/p. La caracterización de reactivos, precursores y películas de PP-PAA-Qs-PYR fue realizada mediante el uso de la espectrometría UV-Visible, infrarroja y de resonancia magnética nuclear, gravimetría, determinación del ángulo de contacto y del espesor de la película. Finalmente, el análisis del desempeño antimicrobiano de las suspensiones acuosas de Qs-PYR y de las películas del PP-PAA-Qs-PYR que contienen Qs-PYR adsorbido en su superficie, se llevó a cabo en el caldo de cultivo Muller Hilton. Este estudio permitió demostrar la existencia de actividad bacteriostática de los grupos arilamonios pendientes de las cadenas de Qs frente a Staphylococcus aureus, sin evidenciar actividad para Escherichia coli. Esta tendencia podría explicarse a partir de diferencias estructurales existentes en la envoltura celular bacteriana, resultando en el caso de la Gram negativa una capa protectora eficiente frente a estos biocidas. Además, se pudo demostrar que la actividad antimicrobiana de Qs- PYR frente a S. aureus crece con el contenido de grupos amonios, mostrando el siguiente orden decreciente: Qs-PYR-0 > Qs-PYR-2 ≥ Qs-PYR-1. Sin embargo, el desempeño biocida de Qs-PYR es mejorado cuando es adsorbido sobre la película de PP-PAA, exhibiendo el siguiente orden decreciente modificado: Qs-PYR2 > Qs- PYR1 > Qs-PYR0. Ambas evidencias sugieren que las interacciones de Qs-PYR con los grupos carboxilos de PAA, generadas durante la adsorción, inducen una reestructuración conformacional del polisacárido en la superficie de la película que favorecen la accesibilidad hacia los grupos arilamonios. Además, un mayor grado de sustitución del anillo aromático parece mejorar la actividad biocida de la superficie, una tendencia que es consistente con la hipótesis planteada inicialmente. Los datos obtenidos hasta el momento resultan ser alentadores, señalando además la tarea a completar para generar las superficies propuestas con las propiedades adecuadas.The research subject of this thesis was focused on the development of active surfaces containing quaternary aryl ammonium groups (PYR) grafted to chitosan (Qs) chains, which provide antimicrobial activity. These Qs derivatives were adsorbed by electrostatic interaction on the surface of polypropylene (PP) film modified with a 2 % wt of polyacrylic acid (PAA). Firstly, a family of quaternary aryl ammonium salts such as 4-bromobutyl-pyridinium bromide (PYR0), 4-bromobutyl- 2-methylpyridinium bromide (PYR1) and 4-bromobutyl-2,4-dimethylpyridinium (PYR2) were synthesized from a bimolecular nucleophilic substitution reaction between the N atom of pyridinic ring and a terminal end (-CH 2 Br) of 1,4- dibromobutane. After evaluating the effect of the solvent, temperature and reaction time, an average yield near 75 % was obtained in the following decreasing order: PYR2 > PYR1 > PYR0. Subsequently, these salts were covalently grafted to Qs chains (yield near 73 %) from the substitution reaction between the halogenated PYR terminal and the amino group of Qs. Later, Qs-PYR derivatives were adsorbed on the PP-PAA film surface by electrostatic interactions among the PAA carboxyl and the amino group of Qs, reaching an average immobilization degree near 1.7 % wt. Reagents, precursors, and PP-PAA-Qs-PYR films were characterized through UVVisible, infrared and nuclear magnetic resonance spectrometry, gravimetry, the contact angle and determination of the film thickness. Finally, the antimicrobial activity analysis of aqueous Qs-PYR suspensions and PP-PAA-Qs-PYR films was performed in a Muller Hinton broth. This study supports the existence of bacteriostatic activity from the aryl ammonium group - grafted to Qs chains against Staphylococcus aureus, but without showing activity for Escherichia coli. This trend could be explained by structural differences in the bacterial cell envelope, resulting in the Gram-negative bacteria a very efficient protective layer against these biocides. It was possible to demonstrate that the antimicrobial activity of Qs-PYR vs S. aureus increases with the ammonium group content, showing the following decreasing order: Qs-PYR-0 > Qs-PYR-2 ≥ Qs-PYR- 1. However, the biocidal performance of Qs- PYR is improved when it is adsorbed on the PP-PAA film, exhibiting the following modified decreasing order: Qs-PYR2 > Qs-PYR1 > Qs-PYR0. Both pieces of evidence suggest that during adsorption the generated interactions between Qs-PYR and the PAA carboxyl groups produce a conformational restructuring of the polysaccharide coil on the film surface that favors accessibility to the aryl ammonium groups. In addition, a higher substitution degree the aromatic ring seems to enhance the biocidal surface activity, a trend that is consistent with the hypothesis initially raised. The data obtained turns out to be encouraging, indicating the task to be carried out to generate the proposed surfaces with appropriate properties.2025-11-30Fil: Pastrana Cabrera, Luisa Fernanda. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina
Juan Bautista Cabrera Ivars: un reformador protestante en el siglo XIX español
No full textThis article synthesizes the biography of Juan Bautista Cabrera Ivars within the legal context of the period. It underlines Cabrera’s role as both an organizer and a reformer and introduces the novelty of his election as a member of the prestigious Hispanic Society of America. A number of previously unpublished documents are included within the article; likewise, in the appendix, the author classifies Cabrera’s written works, almost all of which resulted from his fervor as a reformer, and gives statistics of the growth of Protestantism in Spain from the sixteenth century until today.El trabajo presenta, siguiendo un criterio cronoespacial, una síntesis de la biografía de Juan Bautista Cabrera Ivars, precedida de una breve descripción del ordenamiento jurídico en que transcurre. Se presta atención particular a la obra organizativa y reformista y se destaca el hecho novedoso de haber sido elegido miembro de la Hispanic Society of America. En el cuerpo del texto se reproducen algunos documentos inéditos y en apéndice se adjunta una clasificación de la obra escrita, surgida casi toda ella del impulso reformador y como complemento de tal empresa, y una estadística del desarrollo del protestantismo en España
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