Crossover between the Dense Electron-Hole Phase and the BCS Excitonic Phase in Quantum Dots

Second order perturbation theory and a Lipkin-Nogami scheme combined with an exact Monte Carlo projection after variation are applied to compute the ground-state energy of $6\le N\le 210$ electron-hole pairs confined in a parabolic two-dimensional quantum dot. The energy shows nice scaling properties as N or the confinement strength is varied. A crossover from the high-density electron-hole phase to the BCS excitonic phase is found at a density which is roughly four times the close-packing density of excitons.Comment: Improved variational and projection calculations. 17 pages, 3 ps figures. Accepted for publication in Int. J. Mod. Phys.

Phase Sensitivity of a Mach-Zehnder Interferometer

The best performance of a Mach-Zehnder interferometer is achieved with the input state |N_T/2 + 1>|N_T/2-1 > + |N_T/2 - 1>|N_T/2+1>, being N_T the total number of atoms/photons. This gives: i) a phase-shift error confidence C_{68%}=2.67/N_T with ii) a single interferometric measurement. Different input quantum states can achieve the Heisenberg scaling ~ 1/N_T but with higher prefactors and at the price of a statistical analysis of two or more independent measurements.Comment: 4 figure

Expression of Interleukin-1 and Temporomandibular Disorder: Contemporary Review of the Literature

Objective: Temporomandibular disorders (TMD) are a group of conditions affecting the temporomandibular joint (TMJ), leading to jaw dysfunction, joint and muscle pain, and a decrease in quality of life. A communication network of pro- and anti-inflammatory mediators called cytokines maintains the homeostasis of the TMJ. This review will focus on the Interleukin (IL) family of cytokines, which have been quantified in TMJ synovial fluids in a variety of studies. IL-1α and IL-1β have pro-inflammatory effects, while the endogenous receptor antagonist (IL-1RA) inhibits the pro-inflammatory effects of IL-1. Methods: A literature search (2006–2016) to identify eligible studies was completed using the PubMed database. Studies identified used saline irrigation to quantify cytokine profiles in synovial fluid of healthy and/or dysfunctional joints. Results: The initial search yielded 111 articles, 5 of which met the inclusion criteria after inter-reviewer discussion. Conclusions: Articles that compared IL-1 concentrations in TMD vs. control groups found significant differences

Desulfovibrio desulfuricans isolates from the gut of a single individual: Structural and biological lipid A characterization

AbstractThe levels of sulfate-reducing bacteria (SRB), including Desulfovibrionaceae, in the gut increase following a fat-enriched diet. Endotoxins from gut microbiota contribute to the inflammation process, leading to metabolic diseases. Thus, we sought to characterize the lipid A structures of Desulfovibrionaceae lipopolysaccharides (LPS) that are associated with the microbiota inflammatory properties. LPS variants were obtained from two SRB isolates from the gut of a single individual. These LPS variants shared similar lipid A moieties with Enterobacterial LPS, but differed from one another with regard to fatty-acid numbers and endotoxic activity. This first complete structural characterization of Desulfovibrio lipid A gives new insights into previously published data on Desulfovibrio lipid A biosynthesis. LPS microdiversity within SRBs illustrates how adaptation can influence pro-inflammatory potential

Reduced stiffness buckling analysis of aboveground storage tanks with thickness changes

The Reduced Stiffness Analysis (RSA) to compute lower bounds to buckling loads of shells has been employed by a number of researchers as a simple way to evaluate the buckling capacity of shells that display unstable behavior and imperfection-sensitivity. It allows the use of simple eigenvalue analysis, without having to perform incremental nonlinear analysis, and is based on the physical behavior of the shell which recognizes that a significant contribution to the stability of a shell under lateral pressure is provided by its membrane stiffness. Unstable post-critical behavior is associated with the loss of this stabilizing membrane contribution. Past use of the approach has been mainly restricted to cases of uniform shell thickness and uniform pressures in the circumferential direction, in which case analytical solutions are possible. Recent applications by the authors and other researchers have shown ways to compute the lower bounds using finite element analysis, for which a modified eigenvalue analysis is constructed by neglecting the membrane contributions to the matrix containing the initial stresses. This paper illustrates the application of the methodology to cases of pressure loaded shells with thickness changes in the meridional direction. A semi-analytical finite element code has been employed for the buckling analysis when uniform pressures act on aboveground steel tanks. The tanks are representative of those constructed for the oil industry, with diameter to thickness ratios of the order of 3000, and height to diameter ratios lower than one.Fil: Jaca, Rossana Claudia. Universidad Nacional del Comahue; ArgentinaFil: Godoy, Luis Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Estudios Avanzados en Ingeniería y Tecnología. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Estudios Avanzados en Ingeniería y Tecnología; ArgentinaFil: Croll, James G. A.. University College London; Reino Unid

Relative recoilless F-factors in REFeO3 (RE = rare-earth La, Pr, Nd and Sm) orthoferrites synthesized by self-combustion method

ABSTRACT: In this work, rare-earth orthoferrites polycrystalline compounds REFeO3 (REFO) with RE = rare-earth La, Pr, Nd and Sm were synthesized by the self-combustion method. A direct correlation between the magnitude of the magnetic hyperfine field and the FeAO1AFe bond angles was observed. From transmission Mössbauer spectra recorded at room-temperature, relative recoilless F-factors for these REFO compounds were estimated. The method applied to perform this calculation was based on the determination of two subspectral areas present in a mixture of known amounts of the compound under study and a standard sample (a-Fe). For that purpose spectra were thickness-corrected and fitted using lorentzian lines. The so obtained factors were F-REFeO3 (RE = rare-earth La, Pr, Nd and Sm): 1.30 ± 0.02, 1.08 ± 0.04, 1.15 ± 0.05, 1.18 ± 0.08 respectively. The absolute recoilless factors obtained by this method had an average relative error around 11% in comparison with the values predicted by the Debye model

PROTOTIPO DE TECNOLOGÍA EN ASISTENCIA PARA LA ENSEÑANZA DEL BRAILLE

Con el diseño y fabricación del dispositivo denominado sistema electrónico mecánico para el aprendizaje la lectoescritura del Braille (SEMLEB), junto con la aplicación de una metodología basada en acompañamiento de un tutor, se buscó determinar y analizar los factores que facilitaran el proceso de aprendizaje de la lectoescritura del sistema Braille para niños ciegos en etapa escolar y sus repercusiones en el aprendizaje del castellano para identificar las letras del alfabeto, los fonemas, las sílabas, y algunas palabras y frases de corta longitud

On the mismatches between the monetary and social values of air purification in the colombian andean region: a case study

There is growing interest in air quality and air purification, due to current high pollution levels, their effects on human health, and implications for urban economies. Since the improvement of air quality carries important economic value, air-related benefits have been evaluated monetarily from two perspectives: the first relates to air quality improvements, while the second values air purification as an ecosystem function. This research opted for the second perspective, given that the study area (two Colombian municipalities) does not suffer from poor air quality conditions, but stakeholders prioritized this function as highly important to them. Contingent valuation methods were applied in order to identify the population’s probability of willingness to maintain the air purification function. Although individuals (n = 245) attribute a yearly monetary value of USD 1.5 million to air purification, it was found that, despite the high level of social importance that respondents assigned to air purification (mean = 4.7/5), this had no correlation with payment values (rho = 0.0134, p = 0.8350); that is, households do not really recognize the monetary value of all the benefits they receive or the benefits they would lose if the service suffers changes. Hence, it is posed that monetary values do not necessarily reflect the social importance that individuals assign to ecosystem services, and attention is called to the need to integrate social and monetary values into decision-making processes, so as to encompass the complexity of ecosystem services and conciliate conflicting valuation language

Edge Face Recognition System Based on One-Shot Augmented Learning

There is growing concern among users of computer systems about how their data is handled. In this sense, IT (Information Technology) professionals are not unaware of this problem and are looking for solutions to meet the requirements and concerns of their users. During the last few years, various techniques and technologies have emerged that allow us to answer to the problem posed by users. Technologies such as edge computing and techniques such as one-shot learning and data augmentation enable progress in this regard. Thus, in this article, we propose the creation of a system that makes use of these techniques and technologies to solve the problem of face recognition and form a low-cost security system. The results obtained show that the combination of these techniques is effective in most of the face detection algorithms and allows an effective solution to the problem raised