229 research outputs found

    Primary Epstein-Barr virus infection in a 40-day-old infant

    Get PDF
    Most cases of primary Epstein-Barr virus (EBV) infection during infancy and early childhood are mild or subclinical; therefore, the diagnosis of an EBV infection is not performed easily in this age group. Infectious mononucleosis (IM) is rarely reported during infancy. We report a 40-day-old infant with cervical node enlargement, cough, and coryza symptoms who was finally identified as having a case of primary IM based on the patient's clinical features and serological tests. © 2013 - IOS Press and the authors. All rights reserved

    Tessier number 30 clefts with congenital heart defects

    Get PDF
    Introduction: Midline cleft of mandible, classified as Tessier 30 clefts is extremely rare, with less than 100 reported cases in the latest studies. Variations in severity and associated malformations have been reported before. Case Presentation: In this report, we present the first documented Iranian case of Tessier 30 with median cleft of lower lip and bifid tongue concomitant with congenital heart defects. Conclusions: We explain embryologic origin, differential diagnosis, other associated anomalies and its treatment by reviewing literature. © 2015, Iranian Red Crescent Medical Journal

    Optimal operation of an energy hub considering the uncertainty associated with the power consumption of plug-in hybrid electric vehicles using information gap decision theory

    Full text link
    © 2019 Elsevier Ltd An energy hub is a multi-carrier energy system that is capable of coupling various energy networks. It increases the flexibility of energy management and creates opportunities to increase the efficiency and reliability of energy systems. When plug-in hybrid electric vehicles (PHEVs)are incorporated into the energy hub, batteries can act as an aggregated storage system, increasing the potential integration of variable renewable energy sources (RES)into power system networks. This paper presents a new model for the optimal operation of an energy hub that includes RES, PHEVs, fuel cell vehicles, a fuel cell, an electrolyzer, a hydrogen tank, a boiler, an inverter, a rectifier, and a heat storage system. A novel model is developed to estimate the uncertainty associated with the power consumption of PHEVs during trips using information gap decision theory (IGDT)under risk-averse and risk-seeking strategies. Simulation results demonstrate that the proposed method maximizes the objective function under the risk-neutral and risk-averse strategies, while minimizing the objective function under the risk-seeking strategy. Results from the modeling show that considering the uncertainty associated with the power consumption of PHEVs using IGDT enables the energy hub operator to make appropriate decisions when optimizing the operation of the energy hub against possible changes in power consumption of PHEVs

    The Association Between Obstructive Sleep Apnea and Depression in Older Adults

    Get PDF
    Background: Depression is the most frequent psychiatric disorder among the elderly. Obstructive sleep apnea (OSA) is a chronic and prevalent disease that has an ambiguous role in triggering depression. Several researches with contradictory findings have been performed about the association between OSA and depression. Objectives: This study aimed to investigate the association between OSA and depression among elderly. Patients and Methods: A total of 350 home residing elderly took part in this case-control study. The participants were selected using clustering method. All cases were divided into two groups of depressed and non-depressed using the geriatric depression scale (GDS). Then they were matched in age, gender, education and body mass index (BMI). Berlin questionnaire (BQ) was used to diagnose OSA. Data analysis was performed using Mann-Whitney U test, t-test, Chi-square and Fisher’s exact tests and odds ratio. Results: Totally, 60.6 % of depressed group and 18.9 % of non-depressed group were in high risk for OSA. A significant association was found between OSA and depression (P < 0.001, OR = 6.61, CI 95 % = 4.1 - 10.7). In addition, a significant association was found between gender and OSA (P = 0.008). Conclusions: OSA was associated with depression among the elderly patients. Given the high prevalence of OSA in older adults, implementation of screening methods is necessary to identify people at high risk of OSA

    Behavior of expanded polystyrene (EPS) blocks under cyclic pavement foundation loading

    Get PDF
    This study introduces a mechanism for initial assessment and future development to improve understanding of expanded polystyrene (EPS) behavior as a super-lightweight material for road construction. Large scale cyclic plate load tests on model pavements were performed. The effect of several factors including thickness of soil, thickness of subsequent EPS layers and density of EPS on the surface deformations, resilient modulus (Mr) and interlayer pressure transfer were investigated. The results indicated that, compared to a covering soil layer of 300 mm, the rut depth on the loading surface reduced by 13.5% and 40.8% when the soil thickness was increased by 33% and 100%, respectively. With a constant soil thickness, increasing the thickness of an upper (denser) EPS layer with respect to a bottom (softer) EPS layer, from 200 mm to 600 mm, would only result in a 20% decrease in the peak settlements after loading. Resilient modulus of the system was found to be dependent on soil thickness. A designer can choose an appropriate resilient modulus assuming the soil-EPS composite acts as subgrade or subbase. In order to extend the results to a wider range of geofoams, soils and layer thicknesses, a simple stress analysis method was also trialed

    Experimental Evaluation of Geocell and EPS Geofoam as Means of Protecting Pipes at the Bottom of Repeatedly Loaded Trenches

    Get PDF
    © 2020 American Society of Civil Engineers. With growing populations and continuing urban development, embedding pipes in the ground that are then overrun by traffic is inevitable. This paper describes full-scale prototype tests on high-density polyethylene (HDPE) flexible pipes (of 250 mm diameter), buried at shallow depth, under simulated traffic loading. The paper studies the effect of surface load diameter (0.6×, 0.8×, and 1× pipe diameter) and the amplitude of repeated load (400 or 800 kPa) on pipe behavior. The effects of expanded polystyrene (EPS) geofoam blocks of various densities and also of geocells as a three-dimensional (3D) reinforcement in reducing the pressure transferred to the pipe, the deformation of the pipe, and the surface settlement of the backfill were investigated. The results show that, with an increase in loading surface diameter, the pipe's vertical diametral strain, the pressure transferred to the pipe, and the surface settlement grow significantly, irrespective of applied pressure. Using an EPS block over the pipe increases the soil settlement but reduces transferred pressure onto the pipe and, consequentially, results in lower pipe deformations. The increase in density of an EPS block helps improve response but was still found to be insufficient to prevent increase in surface deflections. The use of geocell reinforcement beneath the loading surface not only reduces the pressure transferred to the pipe and decreases its deformation but also significantly negates the tendency of the EPS block to increase the soil surface settlement. Thus, a geocell reinforcement layer placed over two EPS geofoam blocks (with total thickness 0.3× and width 1.5× the pipe diameter) all above a pipe buried at a depth of twice the pipe diameter, was found to deliver an acceptable, stable response. By these means, the vertical pipe strain, transferred pressure over the pipe, and soil surface settlement were reduced, respectively, by 0.45, 0.37, and 0.53× those obtained for the comparable unmodified buried pipe installation and are within allowable limits

    Density Functional Theory Study of the Hydrogenation of Carbon Monoxide over the Co (001) Surface: Implications for the Fischer–Tropsch Process

    Get PDF
    The increasing demand for renewable fuels and sustainable products has encouraged growing interest in the development of active and selective catalysts for the conversion of carbon monoxide into desirable products. The Fischer–Tropsch process consists of the reaction of a synthesis gas mixture containing carbon monoxide and hydrogen (syngas), which are polymerized into liquid hydrocarbon chains, often using a cobalt catalyst. Here, first-principles calculations based on the density functional theory (DFT) are used to investigate the reaction mechanism of the Fischer–Tropsch synthesis over the Co (001) surface. The most energetically favorable adsorption configurations of the species involved in the carbon monoxide hydrogenation process are identified, and the possible elementary steps of hydrogenation and their related transition states are explored using the Vienna Ab initio simulation package (VASP). The results provide the mechanisms for the formation of CH4, CH3OH and C2H2 compounds, where the calculations suggest that CH4 is the dominant product. Findings from the reaction energies reveal that the preferred mechanism for the hydrogenation of carbon monoxide is through HCO and cis-HCOH, and the largest exothermic reaction energy in the CH4 formation pathway is released during the hydrogenation of cis-HCOH (−0.773 eV). An analysis of the kinetics of the hydrogenation reactions indicates that the CH production from cis-HCOH has the lowest energy barrier of just 0.066 eV, and the hydrogenation of CO to COH, with the largest energy barrier of 1.804 eV, is the least favored reaction kinetically

    Spatial Asymmetric Two dimensional Continuous Abelian Sandpile Model

    Full text link
    We insert some asymmetries in the continuous Abelian sandpile models, such as directedness and ellipticity. We analyze probability distribution of different heights and also find the field theory corresponding to the models. Also we find the fields associated with some height variables.Comment: 14 Pages, 11 Figure

    Abelian Sandpile Model on the Honeycomb Lattice

    Full text link
    We check the universality properties of the two-dimensional Abelian sandpile model by computing some of its properties on the honeycomb lattice. Exact expressions for unit height correlation functions in presence of boundaries and for different boundary conditions are derived. Also, we study the statistics of the boundaries of avalanche waves by using the theory of SLE and suggest that these curves are conformally invariant and described by SLE2.Comment: 24 pages, 5 figure

    Logarithmic two-point correlators in the Abelian sandpile model

    Full text link
    We present the detailed calculations of the asymptotics of two-site correlation functions for height variables in the two-dimensional Abelian sandpile model. By using combinatorial methods for the enumeration of spanning trees, we extend the well-known result for the correlation σ1,11/r4\sigma_{1,1} \simeq 1/r^4 of minimal heights h1=h2=1h_1=h_2=1 to σ1,h=P1,hP1Ph\sigma_{1,h} = P_{1,h}-P_1P_h for height values h=2,3,4h=2,3,4. These results confirm the dominant logarithmic behaviour σ1,h(chlogr+dh)/r4+O(r5)\sigma_{1,h} \simeq (c_h\log r + d_h)/r^4 + {\cal O}(r^{-5}) for large rr, predicted by logarithmic conformal field theory based on field identifications obtained previously. We obtain, from our lattice calculations, the explicit values for the coefficients chc_h and dhd_h (the latter are new).Comment: 28 page
    corecore