Breached pairing in trapped three-color atomic Fermi gases

We introduce an exactly solvable model for trapped three-color atom gases. Applications to a cigar-shaped trapped cold fermions reveal a complex structure of breached pairing phases. We find two competing superfluid phases at weak and intermediate couplings, each one with two color pair condensates, that can be distinguished from density profile measurements.Comment: 4 pages, 5 figure

Cold In-Place Recycling Mix Design, In-Place Density, and Long-Term Performance in Nevada

The objectives of this study were: a) analyze the impact of different variables on a performance based mix design method for cold in-place recycling (CIR), b) develop a practical method for CIR in-place density determination during construction, and c) conduct long-term performance and benefit-cost analysis of CIR pavements throughout Nevada over the period of 2000-2015.Four types of asphalt emulsions, two contents of lime slurry (4.5 and 6.0%), and two types of reclaimed asphalt pavement (RAP) gradations; a medium graded RAP according to the Pacific Coast Committee on Asphalt Specifications (PCCAS), and a non-graded RAP passing 1.0 inch sieve, were used for the mix design of CIR. The mix designs were conducted following a method using the Superpave gyratory compactor, and evaluated for their moisture susceptibility and raveling performance. Gradation plays a role on the optimum emulsion content (OEC) determination for CIR mixtures, whereas there is no noticeable increase on the performance by using 6.0 or 4.5% lime slurry.Three test methods were used to determine the in-place density of CIR pavements; the Sand Cone test method, the Balloon test method, and permeability testing using the NCAT field permeameter. Density tests were conducted on full scale CIR slabs produced in the laboratory and compared to the actual density of the compacted CIR layer obtained from core samples drilled out of the slabs. Permeability test was difficult to perform, and was discarded due to water leaks around the base of the equipment causing fines to wash away from the CIR mixture while performing the test. The best alternative to estimate the in-place air voids is the Sand Cone method coupled with measuring the bulk density of the cores using the parafilm technique. Field verification conducted on a CIR project in Fernley, Nevada, confirmed the selected test method results.Long-term performance analysis was conducted on CIR pavements constructed in Nevada during the period of 2000-2015. A total of 94 CIR pavements were identified throughout Nevada; 63 CIR pavements with AC overlays and 31 CIR pavements with surface treatments. Pavement condition index (PCI) data indicated that most of the CIR projects are in excellent or in very good condition, at the age of 15 years for CIR pavements with AC overlays and at 12 years for CIR pavements with surface treatments. The benefit cost analysis determined that pavements with lower AADT and lower CIR thickness tend to have higher benefit cost ratio, indicating a strong interaction between the structural design of the CIR pavement and its long-term performance

Quantum phase diagram of the integrable p_x+ip_y fermionic superfluid

We determine the zero temperature quantum phase diagram of a p_x+ip_y pairing model based on the exactly solvable hyperbolic Richardson-Gaudin model. We present analytical and large-scale numerical results for this model. In the continuum limit, the exact solution exhibits a third-order quantum phase transition, separating a strong-pairing from a weak-pairing phase. The mean field solution allows to connect these results to other models with p_x+ip_y pairing order. We define an experimentally accessible characteristic length scale, associated with the size of the Cooper pairs, that diverges at the transition point, indicating that the phase transition is of a confinement-deconfinement type without local order parameter. We show that this phase transition is not limited to the p_x+ip_y pairing model, but can be found in any representation of the hyperbolic Richardson-Gaudin model and is related to a symmetry that is absent in the rational Richardson-Gaudin model.Comment: 12 figure

Repulsive interactions in quantum Hall systems as a pairing problem

23 págs.; 4 figs.; 5 tabs. ; PACS number(s): 73.43.Cd, 02.30.Ik, 74.20.RpA subtle relation between quantum Hall physics and the phenomenon of pairing is unveiled. By use of second quantization, we establish a connection between (i) a broad class of rotationally symmetric two-body interactions within the lowest Landau level and (ii) integrable hyperbolic Richardson-Gaudin-type Hamiltonians that arise in (px+ipy) superconductivity. Specifically, we show that general Haldane pseudopotentials (and their sums) can be expressed as a sum of repulsive noncommuting (px+ip y)-type pairing Hamiltonians. The determination of the spectrum and individual null spaces of each of these noncommuting Richardson-Gaudin-type Hamiltonians is nontrivial yet is Bethe ansatz solvable. For the Laughlin sequence, it is observed that this problem is frustration free and zero-energy ground states lie in the common null space of all of these noncommuting Hamiltonians. This property allows for the use of a new truncated basis of pairing configurations in which to express Laughlin states at general filling factors. We prove separability of arbitrary Haldane pseudopotentials, providing explicit expressions for their second quantized forms, and further show by explicit construction how to exploit the topological equivalence between different geometries (disk, cylinder, and sphere) sharing the same topological genus number, in the second quantized formalism, through similarity transformations. As an application of the second quantized approach, we establish a >squeezing principle> that applies to the zero modes of a general class of Hamiltonians, which includes but is not limited to Haldane pseudopotentials. We also show how one may establish (bounds on) >incompressible filling factors> for those Hamiltonians. By invoking properties of symmetric polynomials, we provide explicit second quantized quasihole generators; the generators that we find directly relate to bosonic chiral edge modes and further make aspects of dimensional reduction in the quantum Hall systems precise. © 2013 American Physical Society.This work has been partially supported by the National Science Foundation under NSF Grants No. DMR-1206781 (A.S.) and No. DMR-1106293 (Z.N.), and by the Spanish MICINN Grant No. FIS2012-34479. G.O. would like to thank the Max-Planck-Institute in GarchingPeer Reviewe

Composite fermion-boson mapping for fermionic lattice models

We present a mapping of elementary fermion operators onto a quadratic form of composite fermionic and bosonic operators. The mapping is an exact isomorphism as long as the physical constraint of one composite particle per cluster is satisfied. This condition is treated on average in a composite particle mean-field approach, which consists of an ansatz that decouples the composite fermionic and bosonic sectors. The theory is tested on the one- and two-dimensional Hubbard models. Using a Bogoliubov determinant for the composite fermions and either a coherent or Bogoliubov state for the bosons, we obtain a simple and accurate procedure for treating the Mott insulating phase of the Hubbard model with mean-field computational cost

Dairy farmers’ willingness to adopt cleaner production practices for water conservation: A discrete choice experiment in Mejia, Ecuador

Worldwide, farming practices directly impact the quality and quantity of both underground and surface water resources. In Mejia, the leading milk-producing region of Ecuador, the adoption rate of conservation practices among farmers is low despite price incentives established by the Agricultural Ministry. Our discrete choice experiment documents stated preferences for water conservation practices of Mejia’s dairy farmers by facing respondents to alternatives described in terms of water-efficient technologies, management of manure and solid waste, and training to resolve conflicts over water use. Estimates derived from our preferred random parameter logit specification imply that the average willingness to pay (WTP) for a solid rain irrigation system is US$147 ha-1; and US$212 ha-1 for training to resolve conflicts. In addition, we report heterogeneity in WTP estimates. These findings can assist in the resolution of current issues in Mejia, including inefficient water irrigation and weak water governance system. Based on our results and the context of our study area, we suggest, first, the adoption of a cost-sharing scheme (given that the WTP for these practices does not cover their implementation cost), and second, the participation of academic institutions to help these water users resolve conflicts, establish their own rules, and improve water governance

Static Model of Cement Rotary Kiln

En este trabajo, se presenta un modelo estático de un horno rotatorio de cemento. El modelo del sistema se obtiene a través de series de polinomio. El modelo propuesto se verifica con datos reales de la planta, donde se obtuvieron resultados óptimos. Los resultados esperados son medidos con respecto a la producción de Clinker. El consumo de combustible se mide en relación con el consumo calorífico. Los resultados esperados del enfoque es el incremento de los beneficios de la empresa a través de la reducción en el consumo de combustible.In this paper, a static model of cement rotary kilns is proposed. The system model is obtained through polynomial series. The proposed model is contrasted with data of a real plant, where optimal results are obtained. Expected results are measured with respect to the clinker production and the combustible consumption is measured in relation with the consumption calorific. The expected result of the approach is the increase of the profitability of the factory through the decrease of the consumption of the combustible

Abscesos cerebrales por Nocardia spp. en una paciente inmunocompetente

The infection by Nocardia spp is not common in immunocompetent patients. The empirical antimicrobial treatment directed by anatomical regions does not contemplate the particularities of the germ and the microbiological analysis is necessary for the specific treatment. We present the case of a previously healthy and immunocompetent patient, without known risk factors for Nocardia spp. infection, with evidence of involvement of the pulmonary parenchyma and the skin and subsequent development of multiple brain abscesses. © 2020 Instituto Nacional de Salud

Fruits and vegetables consumption and depressive symptoms: A population-based study in Peru.

OBJECTIVES: Among different factors, diet patterns seem to be related to depression. The aim of this study was to evaluate the association between the consumption of fruits and/or vegetables and depressive symptoms. METHODOLOGY/PRINCIPAL FINDINGS: A secondary data analysis was conducted using information from a population-based survey from 25 regions from Peru. The outcome was the presence of depressive symptoms according to the Patient Health Questionnaire (cutoff ≥15 to define major depressive syndrome); whereas the exposure was the self-reported consumption of fruits and/or vegetables (in tertiles and using WHO recommendation ≥5 servings/day). The association of interest was evaluated using Poisson regression models controlling for the complex-sample survey design and potential confounders. Data from 25,901 participants were analyzed, mean age 44.2 (SD: 17.7) and 13,944 (54.0%) women. Only 910 (3.8%; 95%CI: 3.5%-4.2%) individuals reported consuming ≥5 servings of fruits and/or vegetables/day; whereas 819 (2.8%; 95%CI: 2.5%-3.1%) had depressive symptoms. Those in the lowest tertile of fruits and/or vegetables consumption had greater prevalence of depressive symptoms (PR = 1.88; 95%CI: 1.39-2.55) than those in the highest tertile. This association was stronger with fruits (PR = 1.92; 95%CI: 1.46-2.53) than vegetables (PR = 1.42; 95%CI: 1.05-1.93) alone. CONCLUSIONS: An inverse relationship between consumption of fruits and/or vegetables and depressive symptoms is reported. Less than 5% of subjects reported consuming the amount of fruits and vegetables recommended by the WHO. There is a need to implement strategies to promote better diet patterns with potential impact on mental health