Perceived changes in quality of life in trauma patients:A focus group study

Quality of life (QoL) following a physical trauma is still insufficiently known from a patient perspective. The aim of this study was to qualitatively report perceived changes in QoL after trauma. Focus groups were conducted. Patients admitted to the hospital were eligible for inclusion if they had a lower extremity trauma, severe injuries, or severe traumatic brain injury (TBI). Patients 75 years or older were invited. To analyze the perceived changes in QoL, open coding was used. Patients ( n = 20, M = 55 years) reported comparable consequences. In the first month posttrauma, physical limitations, independency, pain, and anxiety predominated. Later, patients experienced problems with acceptance. The patients’ feelings of the need to have control over their own situation, their own expectations, and a social network were related to QoL. Compared with the other patient groups, TBI patients reported more psychosocial consequences, and elderly patients reported more difficulties in performing (social) activities. Quality of health care was considered an important aspect in the patients’ perceived QoL, and adequate aftercare was missed according to the patients. The impact of a trauma influences QoL in different health domains. Further improving the quality of aftercare may positively influence trauma patients’ perceived QoL. These results indicated that TBI patients and elderly patients deserve specific attention regarding QoL

Incorporation of Density Matrix Wavefunctions in Monte Carlo Simulations: Application to the Frustrated Heisenberg Model

We combine the Density Matrix Technique (DMRG) with Green Function Monte Carlo (GFMC) simulations. The DMRG is most successful in 1-dimensional systems and can only be extended to 2-dimensional systems for strips of limited width. GFMC is not restricted to low dimensions but is limited by the efficiency of the sampling. This limitation is crucial when the system exhibits a so-called sign problem, which on the other hand is not a particular obstacle for the DMRG. We show how to combine the virtues of both methods by using a DMRG wavefunction as guiding wave function for the GFMC. This requires a special representation of the DMRG wavefunction to make the simulations possible within reasonable computational time. As a test case we apply the method to the 2-dimensional frustrated Heisenberg antiferromagnet. By supplementing the branching in GFMC with Stochastic Reconfiguration (SR) we get a stable simulation with a small variance also in the region where the fluctuations due to minus sign problem are maximal. The sensitivity of the results to the choice of the guiding wavefunction is extensively investigated. We analyse the model as a function of the ratio of the next-nearest to nearest neighbor coupling strength. We observe in the frustrated regime a pattern of the spin correlations which is in-between dimerlike and plaquette type ordering, states that have recently been suggested. It is a state with strong dimerization in one direction and weaker dimerization in the perpendicular direction.Comment: slightly revised version with added reference

Two dimensional frustrated magnetic state in superconducting RuSr2Eu1.5Ce0.5Cu2O10 (Ru-1222)

In this paper we investigate the magnetic state and the role of the crystalline structure in RuSr2Eu1.5Ce0.5Cu2O10 (Ru-1222). Measurements were made in the isomorphic series (Nb1-xRux)Sr2Eu1.5Ce0.5Cu2O10 [(Nb,Ru)-1222], with x between 0 and 1. 3D XY fluctuations above the magnetic transition were not observed in Ru-1222, suggesting a weak inter-plane coupling between the RuO2 layers. The compositional dependence of the magnetic susceptibility shows a rapid broadening with increasing Nb content, explained in terms of a cluster-glass state. The variation of several superconducting parameters as a function of Ru content is linear in the whole concentration range, with no jumps at the critical concentration for which percolation of long range order is expected. 3D Arrhenius and Vogel-Fulcher-type dependencies fail to describe the dynamic properties. Fitting of a generalized Vogel-Fulcher-type dependence, with ln(tau/tau0) = A(T-T0)^-B, yield B = 2.0, in excellent agreement with Monte Carlo simulations for 2D systems. The value deduced for T0 agrees well with the re-opening of hysteresis in the M(H) curves. The observed superconducting and magnetic features are explained in terms of a scenario of 2D magnetic islands at the RuO2 layers, with no long range magnetic order.Comment: submitted to Phys. Rev.

Realization of the one-dimensional anisotropic XY model in a Tb(III)-W(V) chain compound

We report the magnetic behavior of the one-dimensional (1D) cyanido-bridged chain complex [Tb(pzam) 3(H 2O)M(CN) 8] •H 2O, where M = W(V). The system shows qualitatively similar magnetic behavior with its already reported M = Mo(V): a broad anomaly in the specific heat ascribed to the magnetic interactions, a transition to three-dimensional magnetic order at T C = 1.15 K, and comparable magnetization and susceptibility. However, substituting the Mo(V) ion by the larger W(V) causes a drastic change in the symmetry of the Tb(III) g tensor, whereby the magnetic interaction between the Tb(III) and M(V) changes from Ising type into an anisotropic XY exchange. We analyze the data in terms of theoretical predictions for the 1D XYZ Hamiltonian and we find an excellent agreement between the theory and experimental data (J x = 1.89 K, J y = 2J x, J z = 0). © 2012 American Physical Society.This research was supported by a Veni grant from the Netherlands Organization for Scientific Research (NWO) to S.T.. We acknowledge Spanish MINECO for Grants MAT2009-13977-C03 and CSD2007-00010.Peer Reviewe

The relation between hyperinflation and daily activity in COPD patients

Although we did not find any relation between DH and PA, SH could be a useful marker to indicate reduced PA. Many patients used a decreased tidal volume and pursed-lips breathing to counteract DH. Different correlations between SH and PA were found to be present between subjects who either were or were not engaged in an exercise-training program. Therefore, this stratification should also be investigated in future studies

The critical behaviour of the 2D Ising model in Transverse Field; a Density Matrix Renormalization calculation

We have adjusted the Density Matrix Renormalization method to handle two dimensional systems of limited width. The key ingredient for this extension is the incorporation of symmetries in the method. The advantage of our approach is that we can force certain symmetry properties to the resulting ground state wave function. Combining the results obtained for system sizes up-to $30 \times 6$ and finite size scaling, we derive the phase transition point and the critical exponent for the gap in the Ising model in a Transverse Field on a two dimensional square lattice.Comment: 9 pages, 8 figure

A Two-dimensional Infinte System Density Matrix Renormalization Group Algorithm

It has proved difficult to extend the density matrix renormalization group technique to large two-dimensional systems. In this Communication I present a novel approach where the calculation is done directly in two dimensions. This makes it possible to use an infinite system method, and for the first time the fixed point in two dimensions is studied. By analyzing several related blocking schemes I find that there exists an algorithm for which the local energy decreases monotonically as the system size increases, thereby showing the potential feasibility of this method.Comment: 5 pages, 6 figure