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The bound state Bethe–Salpeter amplitude was expressed by Nakanishi using a two-dimensional integral representation, in terms of a smooth weight function g , which carries the detailed dynamical information. A similar, but one-dimensional, integral representation can be obtained for the Light-Front wave function in terms of the same weight function g . By using the generalized Stieltjes transform, we first obtain g in terms of the Light-Front wave function in the complex plane of its arguments. Next, a new integral equation for the Nakanishi weight function g is derived for a bound state case. It has the standard form g = N g , where N is a two-dimensional integral operator. We give the prescription for obtaining the kernel N starting with the kernel K of the Bethe–Salpeter equation. The derivation is valid for any kernel given by an irreducible Feynman amplitude. [ABSTRACT FROM AUTHOR]

We show that the Bethe–Salpeter equation for the scattering amplitude in the limit of zero incident energy can be transformed into a purely Euclidean form, as it is the case for the bound states. The decoupling between Euclidean and Minkowski amplitudes is only possible for zero energy scattering observables and allows determining the scattering length from the Euclidean Bethe–Salpeter amplitude. Such a possibility strongly simplifies the numerical solution of the Bethe–Salpeter equation and suggests an alternative way to compute the scattering length in Lattice Euclidean calculations without using the Luscher formalism. The derivations contained in this work were performed for scalar particles and one-boson exchange kernel. They can be generalized to the fermion case and more involved interactions. [ABSTRACT FROM AUTHOR]

Abstract: The off-mass shell scattering amplitude, satisfying the Bethe–Salpeter equation for spinless particles in Minkowski space with the ladder kernel, is computed for the first time. [Copyright &y& Elsevier]

Abstract: A method for determining the total heat loss coefficient, the effective heat capacity and the net solar gain of a building is presented. The method uses a linear regressions approach based on daily energy consumption combined with readily available meteorological data. The effective heat capacity of the building is evaluated by correlating the energy consumption and outdoor temperature changes from the previous day. The net solar gain of the building is assessed by analysing the data separated into groups by amount of daily solar irradiation. Corrected total heat loss coefficient is determined by explicitly including in the building''s energy balance the accumulated heat and the solar gain. The method has been applied to the analysis of nine public buildings in Spain. An improvement of the estimated heat loss coefficient due to the corrections is observed. The effective heat capacity normalised by the building area is shown to be a useful indicator of the building operation, detecting continuous or intermittent heating. The estimated parameters in this study can enable specific benchmarking, detecting opportunities for energy savings and evaluating their potential. With the increasing implementation of smart metering technologies, the method is promising for application to the analysis of large building stocks. [Copyright &y& Elsevier]

A new method for solving the Bethe-Salpeter (BS) equation is presented. It allows to find the BS amplitude both in Minkowski and in Euclidean spaces as well as the light-front wave function. The method is valid for any kernel given by irreducible Feynman graphs. [Copyright &y& Elsevier]

The extraction of scattering parameters from Euclidean simulations of a Yukawa model in a finite volume with periodic boundary conditions is analyzed both in non relativistic quantum mechanics and in quantum field theory. [Copyright &y& Elsevier]

Abstract: Vector and tensor analysing powers of the (charge-exchange) and (non-charge-exchange) breakup reactions have been measured with the ANKE spectrometer at the COSY ring at a deuteron beam energy of 1170 MeV for small momentum transfers to the low excitation energy or systems. A quantitative understanding of the values of and for the charge-exchange reaction is provided by impulse approximation calculations. The data suggest that spin-flip isospin-flip transitions, which dominate the charge-exchange breakup of the deuteron, are also important in the non-charge-exchange reaction. [Copyright &y& Elsevier]

The objective of the study was to evaluate the efficacy and safety of 800 microg misoprostol (Cytotec) every 8 h for 24 h for pharmacological abortion; the treatment was repeated if abortion did not occur in the first 24-h interval. The first misoprostol doses were always self-administered into the vagina; the second and third doses could be administered orally or vaginally depending on the amount of bleeding. Four-hundred and fifty-two women with gestations between 36 and 63 days were recruited into the study. The main outcomes assessed were: successful abortion (complete abortion without surgery), side effects, mean drop in hemoglobin, vaginal bleeding and mean time of return of menstruation. Complete abortion occurred in 409/452 (90.5%; 95% confidence interval [CI] 87%, 93%) patients. Medication to relieve symptoms was administered to all women before the first misoprostol dose. Vaginal bleeding lasted 15.9 +/- 4.4 days. The mean drop in hemoglobin, measured 14 days after abortion, was statistically significant (p = 0.0001) but without clinical relevance. According to the results obtained, 800 microg of misoprostol administered every 8 h for 24 h could be a valid method for abortion for up to 9 weeks of gestation. [ABSTRACT FROM AUTHOR]

By solving the Faddeev equations for the p̄pn system, we compute the antiproton-deuteron level shifts and widths for the lowest hydrogenic states as well as the corresponding p̄d scattering lengths and volumes. The p̄d annihilation densities are obtained and compared to the nuclear density of deuterium. The validity of the Trueman relation for composite particles is studied. The strong part of N̄N interaction is described by two different optical models, including the p̄p-n̄n coupling and n-p mass difference, while for NN several realistic interactions are used. [ABSTRACT FROM AUTHOR]

Pulsed electric held treatment has been claimed to produce more acceptable chilled citrus juices than those obtained by conventional thermal treatment. The pectin methylesterase activity and the acceptability of nine juices obtained from Clementine mandarins. Valencia oranges, and Ortanique fruits (hybrid of mandarin and orange), untreated, pasteurized (85°C for 10 s). and treated by pulsed electric fields (25 kV/cm for 330 μs), were evaluated. The treatments, selected to reach a similar level of pectin methylesterase inactivation, produced juices that did not differ in acceptability from each other for the three varieties and in all cases were less acceptable than the untreated juice. [ABSTRACT FROM AUTHOR]

Abstract By solving the 5-body Faddeev-Yakubovsky equations in configuration space with realistic nuclear Hamiltonians we have studied the resonant states of 5H isotope. Two different methods, allowing to bypass the exponentially diverging boundary conditions, have been employed providing consistent results. The existence of 5H broad J π =1/2+,3/2+,5/2+ states as S-matrix poles has been confirmed and compared with the, also calculated, resonant states in 4H isotope. We have established that the positions of these resonances only mildly depend on the nuclear interaction model. [ABSTRACT FROM AUTHOR]

The authors regret that some numerical errors were published in our previous work that we have detected in reconsidering our work some years later for other purposes. We would like to correct them by publishing this "corrigendum". The authors would like to apologise for any inconvenience caused. [ABSTRACT FROM AUTHOR]

Abstract: The charge-exchange break-up of polarised deuterons , where the final diproton system has a very low excitation energy and hence is mainly in the state, is a powerful tool to probe the spin-flip terms in the proton–neutron charge-exchange scattering. Recent measurements with the ANKE spectrometer at the COSY storage ring at 1.6, 1.8, and 2.27 GeV have extended these studies into the pion-production regime in order to investigate the mechanism for the excitation of the isobar in the reaction. Values of the differential cross section and two deuteron tensor analysing powers, and , have been extracted as functions of the momentum transfer to the diproton or the invariant mass of the unobserved system X. The unpolarised cross section in the high region is well described in a model that includes only direct excitation of the Δ isobar through undistorted one pion exchange. However, the cross section is grossly underestimated for low , even when Δ excitation in the projectile deuteron is included in the calculation. Furthermore, direct Δ production through one pion exchange only reproduces the angular dependence of the difference between the two tensor analysing powers. [Copyright &y& Elsevier]

Abstract: The n–d elastic and breakup cross sections are computed by solving the three-body Faddeev equations for realistic and semi-realistic nucleon–nucleon potentials. These cross sections are inserted in the Monte Carlo simulation of the nuclear processes considered in the International Handbook of Evaluated Criticality Safety Benchmark Experiments (ICSBEP Handbook). The results obtained using thes ab initio n–d cross sections are compared with those provided by the most renown international libraries. [Copyright &y& Elsevier]

Background: Postoperative delirium occurs frequently in elderly hip fracture surgery patients and is associated with poorer overall outcomes. Because xenon anaesthesia has neuroprotective properties, we evaluated its effect on the incidence of delirium and other outcomes after hip fracture surgery.Methods: This was a phase II, multicentre, randomized, double-blind, parallel-group, controlled clinical trial conducted in hospitals in six European countries (September 2010 to October 2014). Elderly (≥75yr-old) and mentally functional hip fracture patients were randomly assigned 1:1 to receive either xenon- or sevoflurane-based general anaesthesia during surgery. The primary outcome was postoperative delirium diagnosed through postoperative day 4. Secondary outcomes were delirium diagnosed anytime after surgery, postoperative sequential organ failure assessment (SOFA) scores, and adverse events (AEs).Results: Of 256 enrolled patients, 124 were treated with xenon and 132 with sevoflurane. The incidence of delirium with xenon (9.7% [95% CI: 4.5 -14.9]) or with sevoflurane (13.6% [95% CI: 7.8 -19.5]) were not significantly different (P=0.33). Overall SOFA scores were significantly lower with xenon (least-squares mean difference: -0.33 [95% CI: -0.60 to -0.06]; P=0.017). For xenon and sevoflurane, the incidence of serious AEs and fatal AEs was 8.0% vs 15.9% (P=0.05) and 0% vs 3.8% (P=0.06), respectively.Conclusions: Xenon anaesthesia did not significantly reduce the incidence of postoperative delirium after hip fracture surgery. Nevertheless, exploratory observations concerning postoperative SOFA-scores, serious AEs, and deaths warrant further study of the potential benefits of xenon anaesthesia in elderly hip fracture surgery patients.Clinical Trial Registration: EudraCT 2009-017153-35; ClinicalTrials.gov NCT01199276. [ABSTRACT FROM AUTHOR]

In the development of dynamic models for the energy performance evaluation of building integrated natural ventilated PV components there are still many open questions regarding the uncertainty of the estimated parameters of the models. Traditionally, the dynamic models for these complex components are derived from the heat transfer balance equations, and the unknown heat transfer coefficients (convection and radiation), the solar properties of the materials or the pressure coefficients for the air mass flow rate balance, are assigned based on literature or on manufacturer prescriptions. However, there is a lack of systematic methods able to validate the simulation outputs with the measured data, taking into consideration the uncertainty of the parameters and their effect over the results. This research is focused on the development of a dynamic simulation model for a PV ventilated component, and on the application of a data-driven iterative approach to identify the unknown parameters, to evaluate their influence in the simulation outputs and finally, to determine the deviations of the simulations outputs against the measured data. During the identification process, 43 unknown parameters are detected and 13 of them are categorized as strong parameters. The implemented data driven approach is able to achieve high goodness of fit with the measured data and it is recommended to analyses which aim at evaluating the influence of some component parameters or the thermal and electrical energy produced by these natural ventilated PV components. [ABSTRACT FROM AUTHOR]

The charge exchange of vector polarised deuterons on a polarised hydrogen target has been studied in a high statistics experiment at the COSY-ANKE facility at a deuteron beam energy of T d = 726 MeV . By selecting two fast protons at low relative energy E p p , the measured analysing powers and spin correlations are sensitive to interference terms between specific neutron–proton charge-exchange amplitudes at a neutron kinetic energy of T n ≈ 1 2 T d = 363 MeV . An impulse approximation calculation, which takes into account corrections due to the angular distribution in the diproton, describes reasonably the dependence of the data on both E p p and the momentum transfer. This lends broad support to the current neutron–proton partial wave solution that was used in the estimation. [ABSTRACT FROM AUTHOR]

The vector and tensor analysing powers, A y and A y y , of the p d → → n { p p } s charge-exchange reaction have been measured at a beam energy of 600 MeV at the COSY-ANKE facility by using an unpolarised proton beam incident on an internal storage cell target filled with polarised deuterium gas. The low energy recoiling protons were measured in a pair of silicon tracking telescopes placed on either side of the target. Putting a cut of 3 MeV on the diproton excitation energy ensured that the two protons were dominantly in the S 0 1 state, here denoted by { p p } s . The polarisation of the deuterium gas was established through measurements in parallel of proton–deuteron elastic scattering. By analysing events where both protons entered the same telescope, the charge-exchange reaction was measured for momentum transfers q ≥ 160 MeV / c . These data provide a good continuation of the earlier results at q ≤ 140 MeV / c obtained with a polarised deuteron beam. They are also consistent with impulse approximation predictions with little sign evident for any modifications due to multiple scatterings. These successful results confirm that the ANKE deuteron charge-exchange programme can be extended to much higher energies with a polarised deuterium target than can be achieved with a polarised deuteron beam. [ABSTRACT FROM AUTHOR]

The aim of this research is to evaluate the increase of biogas production with low cost tubular digesters in cold climates using PET rings inside the reactor. Two similar digesters have been operated and monitored in cold weather conditions and have been fed with cow manure. Digester 1 was filled with PET – rings as a biofilm carrier, Digester 2 was kept as a reference. Through the PET – rings the functional surface could be increased by a factor 4.2. The results show that 44% more biogas per KgSV has been produced with the biofilm carrier in use (0.33 m³/kgSV) (reference digester -0.23 m³/kgSV), at an organic load rate of 0.26 kgSV/m³/d. The thermal performance shows that with an adaptation of the low cost tubular digester the slurry temperature can be raised up to 16.6 °C (average) by surrounding temperature of 6.1 °C (average) without using any active heating system. [ABSTRACT FROM AUTHOR]

Background: Bone scintigraphy used as a diagnostic technique frequently yields non-specific intense uptake by vertebrae. Bone biopsy may therefore be required to establish a diagnosis in cases of Paget''s disease of bone. The aim of the study was to ascertain the sensitivity and specificity of two new images—heart sign and clover sign—in Paget''s disease of bone. Methods: Two expert rheumatologists analyzed 294 bone scintigraphies of patients with vertebral involvement: 204 without and 90 with Paget''s disease. The presence or absence of the clover or heart signs was determined in each scintigraphy. A specificity and sensitivity study was performed with the data obtained. A study of concordance was made between two radiologists blinded to the real diagnosis. Each one analyzed 120 scintigraphies for the presence and absence of the signs: 40 with Paget''s disease and clover and/or heart signs (selected from the initial 90 cases), 40 with Paget''s disease with neither sign and 40 selected from the pool of 4000 scintigraphies of patients with vertebral involvement, with images easily mistaken for these signs (vertebral collapse, osteoarthritis and bone metastases). Kappa statistics were calculated. Findings: Sensitivity of both signs for Paget''s disease of bone was low: 44% (95% CI 34.0 to 55.3). However, specificity was excellent: 100% (95% CI 98.2 to 100). Inter-radiologist concordance was almost perfect: Kappa 0.86 (95% CI 0.77 to 0.95). Interpretation: The heart and clover signs are highly specific (probably pathognomonic) of Paget''s disease of bone. In cases with doubtful radiologic images, these findings on scintigraphic vertebral images may afford a definitive diagnosis of Paget''s disease of bone and thus obviate further confirmatory invasive diagnostic procedures. [Copyright &y& Elsevier]

Objectives This study aimed to characterize the chronically infected general hepatitis C virus (HCV) population in Barcelona using a highly sensitive subtyping method that can identify the 67 recognized HCV subtypes and diagnose mixed infection by various genotypes/subtypes in a single individual. The resulting information has implications for selecting optimal direct-acting antiviral (DAA) treatment for each patient and establishing public healthcare policies in our setting. Methods Consecutive HCV patients (treatment-naïve or interferon-based failures) attending Vall d'Hebron Hospital outpatient clinics from February 2015 to May 2016 ( N = 1473) were included in the study. Patient samples were characterized using HCV subtyping by next-generation ultra-deep pyrosequencing. Results The following genotypes (G) were found: G1 (1126/1473 (76.4%)), G4 (145/1473 (9.8%)), G3 (135/1473 (9.2%)), G2 (51/1473 (3.5%)), and G5 (1/1473 (0.1%)). Twenty-two subtypes were seen: 1b (790/1473 (53.6%)), 1a (332/1473 (22.5%)), 3a (133/1473 (9.0%)), 4d (105/1473 (7.1%)), 4a (29/1473 (2.0%)), and 2c (25/1473 (1.7%)), with 16 low-prevalence subtypes accounting for the remaining 3.0% (44/1473). There was a worrisome 1.0% (15/1473) of mixed infections. G2 (51/1473 (3.5%)) showed a high level of heterogeneity. Analyses by age groups showed a predominance of G1b over G1a (428/506 (84.6%) vs. 24/506 (4.7%)) in patients born before 1950 ( N = 506/1473), and similar percentages of these subtypes in those born between 1951 and 1975 ( N = 834/1473) (315/834, 37.8% vs. 266/834, 31.9%) and after 1976 ( N = 133/1473) (47/133, 35.3% vs. 42/133, 31.6%). Conclusions Subtype distribution showed a higher level of heterogeneity than was expected, particularly for G2. Prevalence of mixed infections was around 1%. HCV subtype distribution related to patient age group suggested that patients born from 1936 to 1975 in our setting should undergo screening for the infection. Next-generation sequencing enabled better classification of candidates for DAA-based treatment. [ABSTRACT FROM AUTHOR]