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The present study aims to integrate the growing body of evidence on the possible association between the severity of chronic inflammatory respiratory disorders (CIRDs) and the frequency of venous thromboembolism (VTE). Eight studies were analyzed to assess the correlation between the severity of CIRDs and the incidence of VTE. Our results suggest that there is no significant increased risk of VTE in patients with severe CIRD compared to mild or moderate CIRD, OR=0.92 (95% CI 0.59 – 1.43; I2 = 74%). Further studies are indicated to explore this possible association. Gaining a better understanding of the VTE risk for patients with CIRDs will enable clinicians to provide better individualized risk management and preventive care.

The calculations of total and binding energies of group IV tetrachlorides MCl4(M = Ti, Zr, Hf, and element 104, Rf) are performed using the four-component fully relativistic density functional method. The calculations show the binding energies to be in good agreement with thermochemical dissociation energies obtained via the Born-Haber. The method demonstrates a predictive power, which is important for further applications in the area of the heavy element compounds.

The objective of this paper is to show that the density fitting (resolution of the identity approximation) can also be applied to Coulomb integrals of the type (k1(1)k2(1)|g1(2)g2(2)), where k and g symbols refer to plane-wave functions and gaussians, respectively. We have shown how to achieve the accuracy of these integrals that is needed in wave-function MO and density functional theory-type calculations using mixed Gaussian and plane-wave basis sets. The crucial issues for achieving such a high accuracy are application of constraints for conservation of the number electrons and components of the dipole moment, optimization of the auxiliary basis set, and elimination of round-off errors in the matrix inversion. [ABSTRACT FROM AUTHOR]

Density fitting approach to Coulomb integrals for infinite systems with translational periodicity is reformulated in direct space. Despite of the Coulomb infinite decay of some integrals, direct-space calculation is shown to be feasible. Moreover, we show that the direct-space ansatz is completely equivalent to our previous formulation in reciprocal space. Computational demands scale linearly with the number of unit cells. In addition, direct-space treatment has some practical advantages over the reciprocal-space formulation. The efficiency of our scheme is demonstrated on systems with translational periodicity in one dimension. Computation time takes only a small fraction of the conventional calculation with exact integrals. We show that for infinite systems auxiliary basis sets of equally good quality as for molecules can be constructed in a systematic way. [ABSTRACT FROM AUTHOR]

The phase behavior of a binary mixture of rodlike and disclike hard molecules is studied using Monte Carlo NVT (constant number of particles N, volume V, and temperature T) computer simulation. The rods are modeled as hard spherocylinders of aspect ratio L[sub HSC]/D[sub HSC]=5, and the discs as hard cut spheres of aspect ratio L[sub CS]/D[sub CS]=0.12. The diameter ratio D[sub CS]/D[sub HSC]=3.62 is chosen such that the molecular volumes of the two particles are equal. The starting configuration in the simulations is a mixed isotropic state. The phase diagram is mapped by changing the overall density of the system. At low densities stabilization of the isotropic phase relative to the ordered states is seen on mixing, and at high densities nematic–columnar and smectic A–columnar phase coexistence is observed. Biaxiality in the nematic phase is not seen. The phase diagram of the mixture is also calculated using the second virial theory of Onsager for nematic ordering, together with the scaling of Parsons and Lee to take into account the higher virial coefficients. The disc–disc and rod–disc excluded volumes are evaluated numerically using the exact overlap expressions, and the lower-order end-effects are incorporated. The exact rod–rod excluded volume is known analytically. In the case of the theoretical calculations, which are limited to translationally disordered phases, coexistence between two uniaxial nematic phases is predicted, as well as the stabilization of the disc-rich isotropic phases. As found in the simulation, biaxial nematic phases are not predicted to be stable. The phase equilibria of an experimental system is also reported which exhibits a behavior close to the system studied by computer simulation. As in the model mixtures, this system exhibits a marked destabilization of the ordered phases on mixing, while nematic–columnar demixing is observed at lower temperatures (the higher-density states). © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The H2020 EU-funded project Hybrid-BioVGE aims to develop an efficient system entirely based on solar energy and biomass for the climatization of buildings during both the heating and cooling seasons. The most innovative component of the concept is a solar-driven Variable Geometry Ejector (VGE) cooling cycle, which can adjust its internal geometry with two degrees of freedom, according to the effective operating conditions. This paper presents the components of the Hybrid-BioVGE concept and describes a demonstrator of the proposed solution installed in a single-family house in Porto (Portugal). The main characteristics of the building, the size and typology of thermal energy storages included in the system are presented as well. In order to demonstrate the energy-saving potential of the Hybrid-BioVGE concept, the numerical model of the demonstrator was implemented in the TRNSYS 18 environment. Outcomes of simulations include the system’s energy performance for both heating and cooling seasons, the achievable solar fraction and the VGE efficiency. Numerical results show that up to 98% of the system energy input derives from renewable sources, with a solar fraction of 61.5%, during the heating season. On the contrary, the seasonal performance factor in cooling operating mode is lower than expected. The VGE cooling cycle efficiency is mainly penalised by the heat rejection loop, which should be optimised to achieve the best performance.