1,514 research outputs found

    Classical Analogue of the Ionic Hubbard Model

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    In our earlier work [M. Hafez, {\em et al.}, Phys. Lett. A {\bf 373} (2009) 4479] we employed the flow equation method to obtain a classic effective model from a quantum mechanical parent Hamiltonian called, the ionic Hubbard model (IHM). The classical ionic Hubbard model (CIHM) obtained in this way contains solely Fermionic occupation numbers of two species corresponding to particles with \up and \down spin, respectively. In this paper, we employ the transfer matrix method to analytically solve the CIHM at finite temperature in one dimension. In the limit of zero temperature, we find two insulating phases at large and small Coulomb interaction strength, UU, mediated with a gap-less metallic phase, resulting in two continuous metal-insulator transitions. Our results are further supported with Monte Carlo simulations.Comment: 12 figure

    Effects of NaCl stress on blood glucose and cortisol in common crap (Cyprinus carpio)

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    In this study, the fluctuation of two parameters of blood glucose and cortisol hormone were investigated in different salinities in Cyprinus carpio. Seven tanks with 100 lit. volume were used and different salinities of 0, 3, 6, 12, 15 and 18 ppm were choosen as treatments. Then, 16 specimen of common carps (each 50-90 g weight) were added to the tanks. In periBds of 12 up to 96 hours, the blood sample was taken from each fish for further measurment of parameters. The results showed that all fishes died at 18 ppm salinity within less than 12 hours. The blood glucose indicated high sensitivity to the higher salinity. In this research, blood glucose had a reange of 13.5 to 321.0 mg/dc.lit and also, cortisol showed a fluctuation from 10 up to 70 µg/dc. lit and its concentration had a direct relationship with increasing the salinity

    The Behaviour of Swine

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    The pig was a forest-dwelling animal from the beginning of its history. In some parts of the world it has been domesticated for at least 7000 years. The European breeds of domestic swine were derived from the local wild pig, Sus scrofa. Herds ranged in pastures and forests and kept indoors only for fattening. The breeds in the Far East were derived from another wild pig, Sus vittatus, a smaller animal with shorter legs and a higher reproductive ability (Mohr 1960; Zeuner 1963). The two types interbred readily. The modem breeds of pig evolved from different crossings between the two original types. They form a rich diversity of genetic material and more than 200 breeds have been catalogued. Certain wild types of pig-like animals, such as the African bush pig (Pontamochoerus larvatus) and the wart hog (Phacochoerus aethiopecus), have never been domesticated. The basis of the social structure in feral swine is the matriarchal herd: one or several females with their offspring. The males are not permanently associated to such herds, often ranging solitary or in \u27bachelor\u27 groups (Fig. 52). Under domestication the pig has been modified from a pugnacious, free-ranging, foraging beast to a more docile animal which is handled readily in large groups under conditions of confined rearing. The behavioural plasticity of swine is emphasized by the rapidity with which wild pigs have adapted to rearing in restricted conditions. Although most of our knowledge of the behaviour of swine has been gained from data collected incidentally to research on nutrition, breeding, physiology and management, a number of experimental studies have recently appeared in learning, adaptation, social, sexual and maternal behaviours, making the pig the best known species among domestic mammals, from the point of view of behaviour

    Classification of retail products: From probabilistic ranking to neural networks

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    Food retailing is now on an accelerated path to a success penetration into the digital market by new ways of value creation at all stages of the consumer decision process. One of the most important imperatives in this path is the availability of quality data to feed all the process in digital transformation. But the quality of data is not so obvious if we consider the variety of products and suppliers in the grocery market. Within this context of digital transformation of grocery industry, \textit{Midiadia} is Spanish data provider company that works on converting data from the retailers' products into knowledge with attributes and insights from the product labels, that is, maintaining quality data in a dynamic market with a high dispersion of products. Currently, they manually categorize products (groceries) according to the information extracted directly (text processing) from the product labelling and packaging. This paper introduces a solution to automatically categorize the constantly changing product catalogue into a 3-level food taxonomy. Our proposal studies three different approaches: a score-based ranking method, traditional machine learning algorithms, and deep neural networks. Thus, we provide four different classifiers that support a more efficient and less error-prone maintenance of groceries catalogues, the main asset of the company. Finally, we have compared the performance of these three alternatives, concluding that traditional machine learning algorithms perform better, but closely followed by the score-based approach.Comment: 17 pages, 8 figures, journa

    A high-finesse Fabry-Perot cavity with a frequency-doubled green laser for precision Compton polarimetry at Jefferson Lab

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    A high-finesse Fabry-Perot cavity with a frequency-doubled continuous wave green laser (532~nm) has been built and installed in Hall A of Jefferson Lab for high precision Compton polarimetry. The infrared (1064~nm) beam from a ytterbium-doped fiber amplifier seeded by a Nd:YAG nonplanar ring oscillator laser is frequency doubled in a single-pass periodically poled MgO:LiNbO3_{3} crystal. The maximum achieved green power at 5 W IR pump power is 1.74 W with a total conversion efficiency of 34.8\%. The green beam is injected into the optical resonant cavity and enhanced up to 3.7~kW with a corresponding enhancement of 3800. The polarization transfer function has been measured in order to determine the intra-cavity circular laser polarization within a measurement uncertainty of 0.7\%. The PREx experiment at Jefferson Lab used this system for the first time and achieved 1.0\% precision in polarization measurements of an electron beam with energy and current of 1.0~GeV and 50~μ\muA.Comment: 20 pages, 22 figures, revised version of arXiv:1601.00251v1, submitted to NIM

    Comparing health-related quality of life in modified Rankin Scale grades : 15D results from 323 patients with brain arteriovenous malformation and population controls

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    Background We wanted to understand how patients with different modified Rankin Scale (mRS) grades differ regarding their health-related quality of life (HRQoL) and how this affects the interpretation and dichotomization of the grade. Methods In 2016, all adult patients in our brain arteriovenous malformation (AVM) database (n = 432) were asked to fill in mailed letters including a questionnaire about self-sufficiency and lifestyle and the 15D HRQoL questionnaire. The follow-up mRS was defined in 2016 using the electronic patient registry and the questionnaire data. The 15D profiles of each mRS grade were compared to those of the general population and to each other, using ANCOVA with age and sex standardization. Results Patients in mRS 0 (mean 15D score = 0.954 +/- 0.060) had significantly better HRQoL than the general population (mean = 0.927 +/- 0.028), p < 0.0001, whereas patients in mRS 1-4 had worse HRQoL than the general population, p < 0.0001. Patients in mRS 1 (mean = 0.844 +/- 0.100) and mRS 2 (mean = 0.838 +/- 0.107) had a similar HRQoL. In the recently published AVM research, the most commonly used cut points for mRS dichotomization were between mRS 1 and 2 and between mRS 2 and 3. Conclusions Using 15D, we were able to find significant differences in the HRQoL between mRS 0 and mRS 1 AVM patients, against the recent findings on stroke patients using EQ-5D in their analyses. Although the dichotomization cut point is commonly set between mRS 1 and 2, patients in these grades had a similar HRQoL and a decreased ability to continue their premorbid lifestyle, in contrast to patients in mRS 0.Peer reviewe

    Open surgical partial nephrectomy for upper tract urothelial carcinoma

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106973/1/iju12301.pd

    Nonlinear Jaynes-Cummings model of atom-field interaction

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    Interaction of a two-level atom with a single mode of electromagnetic field including Kerr nonlinearity for the field and intensity-dependent atom-field coupling is discussed. The Hamiltonian for the atom-field system is written in terms of the elements of a closed algebra, which has SU(1,1) and Heisenberg-Weyl algebras as limiting cases. Eigenstates and eigenvalues of the Hamiltonian are constructed. With the field being in a coherent state initially, the dynamical behaviour of atomic-inversion, field-statistics and uncertainties in the field quadratures are studied. The appearance of nonclassical features during the evolution of the field is shown. Further, we explore the overlap of initial and time-evolved field states.Comment: 14 pages, 6 figures is PS forma

    Cosmological parameter estimation using Very Small Array data out to ℓ= 1500

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    We estimate cosmological parameters using data obtained by the Very Small Array (VSA) in its extended configuration, in conjunction with a variety of other cosmic microwave background (CMB) data and external priors. Within the flat Λ cold dark matter (ΛCDM) model, we find that the inclusion of high-resolution data from the VSA modifies the limits on the cosmological parameters as compared to those suggested by the Wilkinson Microwave Anisotropy Probe (WMAP) alone, while still remaining compatible with their estimates. We find that Ωbh2= 0.0234+0.0012−0.0014, Ωdmh2= 0.111+0.014−0.016, h= 0.73+0.09−0.05, nS= 0.97+0.06−0.03, 1010AS= 23+7−3 and τ= 0.14+0.14−0.07 for WMAP and VSA when no external prior is included. On extending the model to include a running spectral index of density fluctuations, we find that the inclusion of VSA data leads to a negative running at a level of more than 95 per cent confidence ( nrun=−0.069 ± 0.032 ), something that is not significantly changed by the inclusion of a stringent prior on the Hubble constant. Inclusion of prior information from the 2dF galaxy redshift survey reduces the significance of the result by constraining the value of Ωm. We discuss the veracity of this result in the context of various systematic effects and also a broken spectral index model. We also constrain the fraction of neutrinos and find that fν < 0.087 at 95 per cent confidence, which corresponds to mν < 0.32 eV when all neutrino masses are equal. Finally, we consider the global best fit within a general cosmological model with 12 parameters and find consistency with other analyses available in the literature. The evidence for nrun < 0 is only marginal within this model

    Parametric study on the decarbonization potential of structural system and concrete mix design choices for mid-rise concrete buildings

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    Mid-rise reinforced concrete buildings are projected to continue being the predominant typology for urban development. Thus, reducing the carbon footprint of such buildings is critical for achieving a sustainable built environment. Reducing the amount of concrete and steel in a building through structural and mix design optimization is identified as a primary resource efficiency strategy. This paper is among the first to present evidence of the decarbonization potential of these dematerialization strategies on a building level. The study combines structural design choices such as slab system design, steel reinforcement optimization and span width with materials-based strategies, such as low binder concrete and low-carbon binders. For each scenario, material quantities are calculated following design prescriptions by EN1992–1–1 while state-of-the art life cycle inventory data are adopted to calculate the carbon footprint. Results show that shifting towards more efficient structural systems (i.e., waffle slab system) could save up to 20% of the carbon footprint on the building level compared to more traditional systems, such as slab on beams and flat slabs. In addition, reducing the spans from 7.5 to 5 m can save up to 20% more. Finally, the use of low-clinker cement in low-binder concrete can save another 50% in terms of CO2 impact per built-up area. Realistically, results of the case study concluded that implementing these three strategies could reduce the typical 232 kg CO2e/m2 value of the carbon footprint of structural elements of a mid-rise building up to only 58 kg CO2e/m2, i.e., a four-fold reduction
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