1,989 research outputs found

    Logarithmic entropy--corrected holographic dark energy with non--minimal kinetic coupling

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    In this paper, we have considered a cosmological model with the non--minimal kinetic coupling terms and investigated its cosmological implications with respect to the logarithmic entropy-- corrected holographic dark energy (LECHDE). The correspondence between LECHDE in flat FRW cosmology and the phantom dark energy model with the aim to interpret the current universe acceleration is also examined.Comment: 11 pages, 2 figures; Can. J. Phys. Vol. 90, 201

    AdS5AdS_{5} black hole at N=2 supergravity

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    In this paper, we consider the charged non-extremal black hole at five dimensional N = 2 supergravity. We study thermodynamics of AdS_{5} black hole with three equal charges (q_{1} = q_{2} = q_{3} = q). We obtain Schrodinger like equation and discuss the effective potential. Then, we consider the case of the perturbed dilaton field background and find presence of odd coefficients of the wave function. Also we find that the higher derivative corrections have no effect on the first and second even coefficients of the wave function.Comment: 17 pages, 4 figures. Published versio

    The effect of higher derivative correction on η/s\eta /s and conductivities in STU model

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    In this paper we study the ratio of shear viscosity to entropy, electrical and thermal conductivities for the R-charged black hole in STU model. We generalize previous works to the case of a black hole with three different charges. Actually we use diffusion constant to obtain ratio of shear viscosity to entropy. By applying the thermodynamical stability we recover previous results. Also we investigate the effect of higher derivative corrections.Comment: revised versio

    Preventive conservation of vernacular adobe heritage located in seismic-prone regions

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    In general, relevant actions to retrofit heritage should be considered before the occurrence of earthquakes. This proactive approach is preferred, rather than a reactive approach in an emergency situation, following the earthquake. These preventive actions are known as disaster mitigation, risk mitigation, disaster risk management, seismic upgrading and preventive conservation. In the case of vernacular heritage, poor workmanship, lack of financial support, vast number of buildings, and the use of weak material lead to the need to conduct efforts to develop preventive conservation methods with relevant criteria. All these actions were directed to protecting vernacular heritage from multiple potential damages that could threaten this architecture in the future. In recent years, records of casualty and losses due to earthquakes reveal that seismic events can be one of the most destructive potential damages for building, especially if constructed with a weak material, such as adobe. There is little literature concerning preventive conservation of vernacular adobe buildings, which are at risk from earthquakes. Vernacular architecture needs more consideration due to the high number of vernacular dwellings worldwide but especially due to the inhabitants’ safety. Failure to recall the effects of destructive earthquakes with a large recurrent period of seismic actions, but also economic reasons lead to the neglect of these important preventive solutions. The main objective of this paper is to emphasize that a comprehensive conservation procedure related to prevention of casualties and damage of vernacular adobe heritage located in seismic-prone regions, should consider relevant principles and criteria for the conservation of cultural heritage. In the field of preventive conservation of adobe vernacular heritage located in seismic-prone regions, there is some confusion concerning the relation between the conservation process and the seismic protection process; the importance and need of conservation principles in seismic protection procedures; and also the role of the architect and of the engineer in these processes. These matters will be discussed in the current paper.(undefined

    Chemotherapy-Response Monitoring of Breast Cancer Patients Using Quantitative Ultrasound-Based Intra-Tumour Heterogeneities

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    © 2017 The Author(s). Anti-cancer therapies including chemotherapy aim to induce tumour cell death. Cell death introduces alterations in cell morphology and tissue micro-structures that cause measurable changes in tissue echogenicity. This study investigated the effectiveness of quantitative ultrasound (QUS) parametric imaging to characterize intra-tumour heterogeneity and monitor the pathological response of breast cancer to chemotherapy in a large cohort of patients (n = 100). Results demonstrated that QUS imaging can non-invasively monitor pathological response and outcome of breast cancer patients to chemotherapy early following treatment initiation. Specifically, QUS biomarkers quantifying spatial heterogeneities in size, concentration and spacing of acoustic scatterers could predict treatment responses of patients with cross-validated accuracies of 82 ± 0.7%, 86 ± 0.7% and 85 ± 0.9% and areas under the receiver operating characteristic (ROC) curve of 0.75 ± 0.1, 0.80 ± 0.1 and 0.89 ± 0.1 at 1, 4 and 8 weeks after the start of treatment, respectively. The patients classified as responders and non-responders using QUS biomarkers demonstrated significantly different survivals, in good agreement with clinical and pathological endpoints. The results form a basis for using early predictive information on survival-linked patient response to facilitate adapting standard anti-cancer treatments on an individual patient basis

    Breast-Lesion Characterization using Textural Features of Quantitative Ultrasound Parametric Maps

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    © 2017 The Author(s). This study evaluated, for the first time, the efficacy of quantitative ultrasound (QUS) spectral parametric maps in conjunction with texture-analysis techniques to differentiate non-invasively benign versus malignant breast lesions. Ultrasound B-mode images and radiofrequency data were acquired from 78 patients with suspicious breast lesions. QUS spectral-analysis techniques were performed on radiofrequency data to generate parametric maps of mid-band fit, spectral slope, spectral intercept, spacing among scatterers, average scatterer diameter, and average acoustic concentration. Texture-analysis techniques were applied to determine imaging biomarkers consisting of mean, contrast, correlation, energy and homogeneity features of parametric maps. These biomarkers were utilized to classify benign versus malignant lesions with leave-one-patient-out cross-validation. Results were compared to histopathology findings from biopsy specimens and radiology reports on MR images to evaluate the accuracy of technique. Among the biomarkers investigated, one mean-value parameter and 14 textural features demonstrated statistically significant differences (p < 0.05) between the two lesion types. A hybrid biomarker developed using a stepwise feature selection method could classify the legions with a sensitivity of 96%, a specificity of 84%, and an AUC of 0.97. Findings from this study pave the way towards adapting novel QUS-based frameworks for breast cancer screening and rapid diagnosis in clinic

    Capacity and Energy Usage of Translucent and Multi-Band Transparent Optical Networks

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    This work shows that exploiting more bands in a transparent network design is a more effective and power-efficient way to increase the network capacity instead of relying on signal regenerators to increase spectral efficiency

    Algorithm and Software for Proactive Pothole Repair

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    Potholes are a common pavement distress, particularly appearing during the spring freeze-thaw period in northern climates. Potholes reduce ride quality, and if left unrepaired can lead to rapid pavement deterioration. Typically, when a pothole appears a repair crew is dispatched to place patch mixture in the hole with the hope that the patch will last until such time as a more permanent repair can be made. This reactive approach to potholes can often be too late to prevent further pavement damage and also makes it difficult for repairs crews to be scheduled in the most cost effective manner. In this study, the relation between traffic loads combined with weather records, such as temperature, freeze-thaw cycles and the numbers of potholes requiring patching was investigated in an attempt to develop a model to predict pothole formation and distinguish the routes which are prone to pothole formation before the potholes begin to form. If pothole prediction were possible, this proactive approach would enable agencies to plan and schedule maintenance activities more cost and time effectively thus increasing ride safety and mobility. To achieve the objective, four years of maintenance data from Indiana routes were collected and statistically analyzed to develop a model to estimate the probability of occurrence of a pothole due to annual average daily traffic and climate. The model indicates how significant traffic loads combined with weather condition influence the pothole. Also, although traffic loads and weather conditions are the essentials for potholes to form, the effect of pavement condition on the initiation of new potholes cannot be disregarded. Additionally, this study began the development of a basic roadway distress evolution model by employing several standard statistical tools, such as, the empirical cumulative distribution functions (CDF) and the Kolmogorov-Smirnov (KS), to a pavement condition dataset. The goal of the model was to predict and rank areas of probable future concern by likelihood and severity. The resulting analysis showed promise but the data resolution was too low to achieve predictions on the desired fine scale
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