1,151 research outputs found
How to determine whether conceptual endophenotypes can improve clinical outcomes in patients suffering from major depression:an exploratory approach
Sense of coherence, mental well-being and perceived preoperative hospital and surgery related stress in surgical patients with malignant, benign, and no neoplasms
Background: This prospective, cross-sectional, observational study examined associations between sense of coherence (SOC), mental well-being, and perceived preoperative hospital and surgery related stress of surgical patients with malignant, benign, and no neoplasms. The objective was to assess a putative association between SOC and preoperative stress, and to test for a statistical mediation by mental well-being.
Method: The sample consisted of 4918 patients from diverse surgical fields, of which 945 had malignant neoplasms, 333 benign neoplasms, and 3640 no neoplasms. For each subsample, we conducted simple mediation analyses to test an indirect effect of SOC on preoperative stress mediated by mental well-being. The models were adjusted for age, gender, and essential medical factors.
Results: Patient groups did not differ significantly regarding degrees of SOC and mental well-being (SOC, M [SD]: 12.31 [2.59], 12.02 [2.62], 12.18 [2.57]; mental well-being M [SD]: 59.26 [24.05], 56.89 [22.67], 57.31 [22.87], in patients with malignant, benign, and without neoplasms, respectively). Patients without neoplasms reported significantly lower stress (4.19 [2.86], M [SD]) than those with benign (5.02 [3.03], M [SD]) and malignant neoplasms (4.99 [2.93], M [SD]). In all three mediation models, SOC had significant direct effects on stress, with higher SOC being associated with lower stress (- 0.3170 [0.0407], - 0.3484 [0.0752], - 0.2919 [0.0206]; c' [SE], p < 0.001 in patients with malignant, benign, and without neoplasms, respectively). In patients with malignant neoplasms and without neoplasms, SOC showed small indirect effects on stress that were statistically mediated by well-being. Higher SOC was related to higher well-being, which in turn was related to lower stress. In patients with benign neoplasms, however, no significant indirect effects of SOC were found.
Conclusions: SOC was directly associated with lower perceived hospital and surgery related stress, over and above the direct and mediation effects of mental well-being. Because the data are cross-sectional, conclusions implying causality cannot be drawn. Nevertheless, they indicate important relationships that can inform treatment approaches to reduce elevated preoperative stress by specifically addressing low SOC
Internet-based psychoeducation for bipolar disorder: a qualitative analysis of feasibility, acceptability and impact
<p>Background: In a recent exploratory randomised trial we found that a novel, internet-based psychoeducation programme for bipolar disorder (Beating Bipolar) was relatively easy to deliver and had a modest effect on psychological quality of life. We sought to explore the experiences of participants with respect to feasibility, acceptability and impact of Beating Bipolar.</p>
<p>Methods: Participants were invited to take part in a semi-structured interview. Thematic analysis techniques were employed; to explore and describe participants’ experiences, the data were analysed for emerging themes which were identified and coded.</p>
<p>Results: The programme was feasible to deliver and acceptable to participants where they felt comfortable using a computer. It was found to impact upon insight into illness, health behaviour, personal routines and positive attitudes towards medication. Many participants regarded the programme as likely to be most beneficial for those recently diagnosed.</p>
<p>Conclusions: An online psychoeducation package for bipolar disorder, such as Beating Bipolar, is feasible and acceptable to patients, has a positive impact on self-management behaviours and may be particularly suited to early intervention. Alternative (non-internet) formats should also be made available to patients.</p>
Synthesis and Raman micro-spectroscopy investigation of Li7La3Zr2O12
The Li+ ion conductor Li7La3Zr2O12 was synthesized by solid state reaction as a ceramic with tetragonal and cubic crystal structure. The synthesis parameterswere varied for these polycrystalline samples, e.g. the starting materials for Li and Zr, the cruciblematerials and the thermal treatments. Product formation is sensitive to the ZrO2 starting powder aswell as the crucible material due to reactions between the powdermixture and the cruciblewall. In this study, only the use of an alumina crucible or the addition of alumina resulted in the successful preparation of cubic Li7La3Zr2O12.
For single-crystal preparation, flux growth experiments were carried out at 1000 and 1200 \ub0C either in alumina crucibles lined with a gold foil or in magnesia crucibles and using Li2CO3 (Li2O) as flux. The small crystals were separated from the solidified flux by washing larger lumps in water. Irrespective of the additions of alumina, only tetragonal micro-crystals of Li7La3Zr2O12 were obtained.
These micro-crystals were studied by micro-Raman scattering spectroscopy. Polarized Raman spectra were recorded either in nearly backscattering or 90\ub0 geometry. The majority of Raman modes expected for the tetragonal phase (space group I41/acd, Z=8) were satisfactorily displayed. So far, it has not been possible
to make unambiguous symmetry assignments of the observed peaks because of the unknown orientation of the micro-crystals
Promotion of mixed protonic–electronic transport in LaWO membranes under HS atmospheres
Catalytic membrane reactors (CMR) based on H-separation membranes can improve the performance of thermodynamically-limited reactions such as high-pressure steam methane reforming, ammonia cracking, non-oxidative aromatics production, and water gas shift reaction (WGS). In these industrial processes, the membrane surfaces are typically exposed to steam, CO, CO, HS, and hydrocarbons in combination with high temperatures. Therefore, the membrane materials require long-term thermo-chemical stability under the mentioned conditions. Stability in HS is of outstanding importance since its presence, even at ppm level, gives rise to substantial surface poisoning and decomposition of most materials. Here we characterize the influence of HS on the crystalline structure, lattice composition, and hydrogen-transport properties of LaWO, one of the reference protonic membrane materials. The incorporation of sulfide ions in the crystal lattice is ascertained from XRD, XPS, FESEM, WDS, EDS, and FIB-SIMS analyses. UV-vis spectroscopy and EIS measurements illustrate the effect of the incorporated sulfur in the transport properties, i.e., vigorously promoting the electronic conductivity mediated by the concurrent partial reduction of tungsten cations (W). The rise in electronic conductivity allowed an H flux of 0.042 mL cm min to be reached at 700 °C for a ∼700 μm-thick membrane, in contrast with negligible H permeation in HS-free conditions
First-time synthesis of a magnetoelectric core-shell composite via conventional solid-state reaction
In recent years, multiferroics and magnetoelectrics have demonstrated their potential for a variety of applications. However, no magnetoelectric material has been translated to a real application yet. Here, we report for the first time that a magnetoelectric core–shell ceramic, is synthesized via a conventional solid-state reaction, where core–shell grains form during a single sintering step. The core consists of ferrimagnetic , which is surrounded by a ferroelectric shell consisting of . We establish the core–shell nature of these grains by transmission-electron microscopy (TEM) and find an epitaxial crystallographic relation between core and shell, with a lattice mismatch of 6 ± 0.7%. The core–shell grains exhibit exceptional magnetoelectric coupling effects that we attribute to the epitaxial connection between the magnetic and ferroelectric phase, which also leads to magnetic exchange coupling as demonstrated by neutron diffraction. Apparently, ferrimagnetic cores undergo a non-centrosymmetric distortion of the crystal structure upon epitaxial strain from the shell, which leads to simultaneous ferrimagnetism and piezoelectricity. We conclude that in situ core–shell ceramics offer a number of advantages over other magnetoelectric composites, such as lower leakage current, higher density and absence of substrate clamping effects. At the same time, the material is predestined for application, since its preparation is cost-effective and only requires a single sintering step. This discovery adds a promising new perspective for the application of magnetoelectric materials
Al13H−: Hydrogen atom site selectivity and the shell model
Using a combination of anion photoelectron spectroscopy and density functional theory calculations, we explored the influence of the shell model on H atom site selectivity in Al13H−. Photoelectron spectra revealed that Al13H− has two anionic isomers and for both of them provided vertical detachment energies (VDEs). Theoretical calculations found that the structures of these anionic isomers differ by the position of the hydrogen atom. In one, the hydrogen atom is radially bonded, while in the other, hydrogen caps a triangular face. VDEs for both anionic isomers as well as other energetic relationships were also calculated. Comparison of the measured versus calculated VDE values permitted the structure of each isomer to be confirmed and correlated with its observed photoelectron spectrum. Shell model, electron-counting considerations correctly predicted the relative stabilities of the anionic isomers and identified the stable structure of neutral Al13H
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Calculation of the Activity Inventory for the TRIGA Reactor at the Medical University of Hannover (MHH) in Preparation for Dismantling the Facility
It is planned to dismantle the TRIGA reactor facility at the Medical University of Hannover (MHH). Radioactive waste resulting from this dismantling will be disposed of externally, any remaining materials as well as the building structures will then be measured to ensure there is no residual activity. In preparation for this and to plan the techniques which will be used to dismantle the reactor, calculations were made in order to determine the amount of activity and the dose rates for the reactor tank and its inside components as well as for the biological shield and its radial beam tube
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