723 research outputs found
Nonclassicality of states and measurements by breaking classical bounds on statistics
Original article can be found at: http://pra.aps.org/ Copyright American Physical Society. DOI: 10.1103/PhysRevA.79.042105We derive exceedingly simple practical procedures revealing the quantum nature of states and measurements by the violation of classical upper bounds on the statistics of arbitrary measurements. Data analysis is minimum, and definite conclusions are obtained without evaluation of moments or any other more sophisticated procedures. These nonclassical tests are independent of other typical quantum signatures such as sub-Poissonian statistics, quadrature squeezing, or oscillatory statistics. This approach can be equally well applied to very diverse situations such as single- and two-mode fields, observables with continuous and discrete spectra, finite- and infinite-dimensional systems, and ideal and noisy measurements.Peer reviewe
Generalized Limits for Parameter Sensitivity via Quantum Ziv-Zakai Bound
We study the generalized limit for parameter sensitivity in quantum
estimation theory considering the effects of repeated and adaptive
measurements. Based on the quantum Ziv-Zakai bound, we derive some lower bounds
for parameter sensitivity when the Hamiltonian of system is unbounded and when
the adaptive measurements are implemented on the system. We also prove that the
parameter sensitivity is bounded by the limit of the minimum detectable
parameter. In particular, we examine several known states in quantum phase
estimation with non-interacting photons, and show that they can not perform
better than Heisenberg limit in a much simpler way with our result.Comment: 8pages, 5 figure
Characterization of quantum angular-momentum fluctuations via principal components
We elaborate an approach to quantum fluctuations of angular momentum based on
the diagonalization of the covariance matrix in two versions: real symmetric
and complex Hermitian. At difference with previous approaches this is SU(2)
invariant and avoids any difficulty caused by nontrivial commutators.
Meaningful uncertainty relations are derived which are nontrivial even for
vanishing mean angular momentum. We apply this approach to some relevant
states.Comment: 10 pages, Two column. New section II and some clarifying comment
Management Options of Colonoscopic Splenic Injury
Injury to the spleen during routine colonoscopy is an extremely rare injury. Diagnosis and management of the injury has evolved with technological advances and experience gained in the management of splenic injuries sustained in trauma. Of the 37 reported cases of colonoscopic splenic injury, 12 had a history of prior surgery or a disease process suggesting the presence of adhesions. Only 6 had noted difficulty during the procedure, and 31 patients experienced pain, shock, or hemoglobin drop as the indication of splenic injury. Since 1989, 21/24 (87.5%) patients have been diagnosed initially using computed tomography or ultrasonography. Overall, only 27.8% have retained their spleens. None have experienced as long a delay as our patient, nor have any had an attempt at percutaneous control of the injury. This report presents an unusual case of a rare complication of colonoscopy and the unsuccessful use of one nonoperative technique, and reviews the experience reported in the world literature, including current day management options
THE ROLE OF CAPITAL FLOWS IN EXTERNAL CONSTRAINED GROWTH: THE EXPERIENCES OF SPAIN AND PORTUGAL IN THE EUROZONE
Abstract Broadly speaking, the balance-of-payments constraint hypothesis has been empirically supported. Yet, it shows some shortcomings highlighted in the literature. In our opinion, two of them must be analysed. First, temporary disequilibria and capital flows must be incorporated into the balance-ofpayments constrained growth models. Second, the role of relative prices must be made explicit, since it can be relevant even in an external constraint framework. This study is aimed at developing a model that incorporates both possibilities: temporary external disequilibria and the impact of relative prices. This model is subsequently used to analyse the evolution of the Spanish and Portuguese economies in last decades, and, in particular, the different paths shown by both countries since their accession to the Eurozone. JEL: E12, F41, F4
Perfil de los emprendedores en la industria de capital de riesgo en la Región del Maule
103 p.Este proyecto tiene como finalidad caracterizar a los emprendedores de la Region del Maule en base a la motivación, percepción respecto a inversionistas y al éxito, además de su relación con la industria de capital de riesgo. El problema que origina la elaboración de este estudio es el poco desarrollo que presenta la industria de capital de riesgo en nuestro país y la falta de conocimiento, por parte de los inversionistas, acerca de las cualidades que presentan los emprendedores en nuestra zona. Su propósito es ayudar a dar a conocer los negocios que involucran
financiamientos riesgosos y la percepción que presentan los empresarios o emprendedores acerca de la inversión externa para sus negocios. Para entender mejor como se trabaja en proyectos relacionados con capital de riesgo hemos definido, en primer lugar, un marco teórico que explica el
funcionamiento de esta industria y sus involucrados. En cuanto a la recolección de la información esta se llevo a cabo a traves de
la aplicación de un cuestionario a los asistentes a las charlas y seminarios relacionados con capital de riesgo y emprendimiento dictadas durante el mes de Mayo de 2000 en la Universidad de Talca, Campus Lircay y Curico. La principal limitación que presenta el estudio es que las conclusiones solo son validas para la muestra y no pueden ser generalizadas para la población debido
a la falta de un mecanismo para identificar, dentro de los empresarios de la Region, quienes poseían rasgos de emprendedores, por esto el estudio se enfoco hacia los asistentes a dichos seminarios ya que al asistir demostraban tener esta actitud
Bioprospecting of Ureolytic Bacteria From Laguna Salada for Biomineralization Applications
The processes of biomineralization, mediated by ureolytic bacteria, possess a wide range of technological applications, such as the formation of biocements and remediation of water and soil environments. For this reason, the bioprospecting of new ureolytic bacteria is interesting for its application to these technologies, particularly for water treatment. This study demonstrates the isolation, selection, and identification of halotolerant ureolytic bacteria from Laguna Salada (inland from Atacama Desert) and the evaluation of their ability to precipitate calcium carbonate crystals in freshwater in the presence of calcium ions, as well as the ability to induce the precipitation of crystals from different ions present in seawater. Twenty-four halotolerant ureolytic bacteria whose molecular identification gives between 99 and 100% identity with species of the genus Bacillus, Porphyrobacter, Pseudomonas, Salinivibrio, and Halomonas were isolated. When cultivated in freshwater, urea, and calcium chloride, all species are able to biomineralize calcium carbonate in different concentrations. In seawater, the strains that biomineralize the highest concentration of calcium carbonate correspond to Bacillus subtilis and Halomonas sp. SEM–EDX and XRD analyses determined that both bacteria induce the formation of 9–33% halite (NaCl), 31–66% monohydrocalcite (CaCO3 × H2O), and 24–27% struvite (MgNH4PO4 × 6H2O). Additionally, B.subtilis induces the formation of 7% anhydrite (CaSO4). In seawater, B.subtilis and Halomonas sp. were able to precipitate both calcium (96–97%) and magnesium (63–67%) ions over 14 days of testing. Ion removal assays with B.subtilis immobilized in beads indicate a direct relationship between the urea concentration and a greater removal of ions with similar rates to free cells. These results demonstrate that the biomineralization mediated by bacterial urea hydrolysis is feasible in both freshwater and seawater, and we propose its application as a new technology in improving water quality for industrial uses
Cyclobenzaprine raises ROS levels in Leishmania infantum and reduces parasite burden in Infected mice
11 p.-5 fig. Ferreira Cunha-Júnior, Edézio et al.Background
The leishmanicidal action of tricyclic antidepressants has been studied and evidences have pointed that their action is linked to inhibition of trypanothione reductase, a key enzyme in the redox metabolism of pathogenic trypanosomes. Cyclobenzaprine (CBP) is a tricyclic structurally related to the antidepressant amitriptyline, differing only by the presence of a double bond in the central ring. This paper describes the effect of CBP in experimental visceral leishmaniasis, its inhibitory effect in trypanothione reductase and the potential immunomodulatory activity.Methodology/Principal Findings
In vitro antileishmanial activity was determined in promastigotes and in L. infantum-infected macrophages. For in vivo studies, L. infantum-infected BALB/c mice were treated with CBP by oral gavage for five days and the parasite load was estimated. Trypanothione reductase activity was assessed in the soluble fraction of promastigotes of L. infantum. For evaluation of cytokines, L. infantum-infected macrophages were co-cultured with BALB/c splenocytes and treated with CBP for 48 h. The supernatant was analyzed for IL-6, IL-10, MCP-1, IFN-γ and TNF-α. CBP demonstrated an IC50 of 14.5±1.1μM and an IC90 of 74.5±1.2 μM in promastigotes and an IC50 of 12.6±1.05 μM and an IC90 of 28.7±1.3 μM in intracellular amastigotes. CBP also reduced the parasite load in L. infantum-infected mice by 40.4±10.3% and 66.7±10.5% in spleen at 24.64 and 49.28 mg/kg, respectively and by 85.6±5.0 and 89.3±4.8% in liver at 24.64 and 49.28mg/kg, after a short-term treatment. CBP inhibited the trypanothione reductase activity with a Ki of 86 ± 7.7 μM and increased the ROS production in promastigotes. CBP inhibited in 53% the production of IL-6 in infected macrophages coculture.Conclusion/Significance
To the best of our knowledge, this study is the first report of the in vivo antileishmanial activity of the FDA-approved drug CBP. Modulation of immune response and induction of oxidative stress in parasite seem to contribute to this efficacy.This work was supported by Programa Estratégico de Apoio à Pesquisa em Saúde,FIOCRUZ/Conselho Nacional de Desenvolvimento Científico e Tecnológico - www.cnpq.br, (PAPES/
CNPq 407680/2012-8 to ECTS and 407590/2012-9
to EEAA), Fundação de Apoio a Pesquisa do Estado do Rio de Janeiro ± www.faperj.br (Fellow and grant E-26/010.001828/2016 to EFCJ), Conselho Nacional de Desenvolvimento CientõÂfico e
TecnoloÂgico (CNPq/Universal grant 470627/2013-1 to EEAA), São Paulo Research Foundation - www.fapesp.br (FAPESP 2015/23403-9 to AGT),Programa Estatal de Investigación, Desarrollo e Innovación Orientada a los Retos de la Sociedad
FEDER - www.idi.mineco.gob.es/ (SAF2015-65740-R) and Subdirección General de Redes y Centros de Investigación Cooperativa-FEDER -www.isciii.es/ (RD12/0018/0007) (to LR).Peer reviewe
El Instituto Universitario de Urbanística (1991-2021): construcción de una cultura de investigación
[EN] The Instituto Universitario de Urbanística (IUU) (University Institute of Urban Planning) of the Universidad de Valladolid was founded in 1991 and it is the only one of its kind in the Spanish territory. Throughout those three decades of existence, the research group Planificación territorial y urbanística (IUU_Lab) (Territorial and Urban Planning) has developed, as the driving force of the institute, a very diversified activity that this article seeks to analyse and show synthetically, inserted in the urban development in Spain since the 1980s. The study of the scientific production that has marked the group s trajectory as well as the disciplinary influences it has received, allows the authors to characterise four main fields of knowledge construction and disciplinary reflection: reformist urban planning, urban-territorial planning, urban regeneration, and rural environment. The whole analysis developed reveals, on the one hand, some links established between certain problems of Spanish urbanism and research in Urban and Territorial Planning; and, on the other hand, the validity of an epistemological vision of Urban Planning understood as a knowledge of interdisciplinary nature and practical orientation, nurtured by a historical conscience.[ES] El Instituto Universitario de Urbanística (IUU) de la Universidad de Valladolid, único en su género en el territorio español, fue fundado en 1991. En esas tres décadas de existencia, el grupo de investigación Planificación territorial y urbanística (IUU_Lab) ha desarrollado, como motor del instituto, una actividad muy diversificada que este artículo busca analizar y mostrar sintéticamente, inserta en el devenir urbanístico en España desde la década de 1980. El estudio de la producción científica que ha jalonado la trayectoria del grupo y de las influencias disciplinares que ha recibido permite a los autores caracterizar cuatro campos principales de construcción de conocimiento y reflexión disciplinar: la Urbanística reformista, la planificación urbanoterritorial,la regeneración urbana, y el medio rural. Del conjunto del análisis desarrollado se desprenden, por un lado, algunos vínculos establecidos entre determinados problemas del urbanismo español y la investigación en Urbanística y Ordenación del Territorio; y, por otro lado, la vigencia de una visión epistemológica de la Urbanística entendida como un saber de naturaleza interdisciplinar y orientación práctica, nutrida por una consciencia histórica.Castrillo Romón, MA.; Jiménez Jiménez, M.; De Las Rivas Sanz, JL. (2022). The Instituto Universitario de Urbanística (1991-2021): building a research culture. VLC arquitectura. Research Journal. 9(2):217-248. https://doi.org/10.4995/vlc.2022.177642172489
Observation of a tricritical wedge filling transition in the 3D Ising model
In this letter we present evidences of the occurrence of a tricritical filling transition for an Ising model in a linear wedge. We perform Monte Carlo simulations in a double wedge where antisymmetric fields act at the top and bottom wedges, decorated with specific field act- ing only along the wegde axes. A finite-size scaling analysis of these simulations shows a novel critical phenomenon, which is distinct from the critical filling. We adapt to tricritical filling the phenomenological theory which successfully was applied to the finite-size analysis of the critical filling in this geometry, observing good agreement between the simulations and the theoretical predictions for tricritical filling
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