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In the case of a first episode of psychosis among members of different associations of families of mentally ill people, little is known about their priorities and how satisfied they are with the help provided to them. A survey was conducted in five European family associations. Respondents emphasized the need for early (ambulant) intervention through outreach with very practical goals directed at creating stability and social functioning. About one-third of the respondents are unsatisfied or very unsatisfied. The highest percentage of unsatisfied respondents was in the following five areas of care: advice on how to handle specific problems; help with preserving or regaining social functioning; help with regaining structure and routine; information; prompt assistance preferably in patientˈs own environment. The agreement of these findings with findings from earlier studies underlines the importance of suggesting specific changes in the delivery of care.
Psychiatric services providing care for patients and their families confronted with a first psychotic episode need to be sensitive towards patients’ and families’ preferences. Ten patients, ten family members and ten professional caregivers composed a list of 42 preferences in the treatment for a first psychotic episode. In total 99 patients, 100 family members and 263 professional caregivers evaluated these preferences, thus producing an order of priorities. There appears to be considerable agreement among the groups of respondents regarding their top ten priorities, especially concerning information on diagnosis and medication. However, we found important differences between groups of respondents. The results suggest that in psychiatric services great attention should be given to psycho-education and early outpatient intervention.
We report a novel strategy to render stainless steel (SS) a more versatile material that is suitable to be used as the substrate for preparing electrodes for efficient hydrogen evolution by interface engineering. Our strategy involves the growth of carbon nanotubes (CNTs) by atmospheric pressure chemical vapor deposition (APCVD) as the interface material on the surface of SS. We optimized the procedure to prepare CNTs/SS and demonstrate a higher activity of the CNTs/SS prepared at 700 °C for the hydrogen evolution reaction (HER) when compared to samples prepared at other temperatures. This can be attributed to the higher number of defects and the higher content of pyrrolic N obtained at this temperature. Our strategy offers a new approach to employ SS as a substrate for the preparation of highly efficient electrodes and has the potential to be widely used in electrochemistry.
A high-resolution reflection seismic survey was carried out in 1999 over the Feldbiss fault system, the southern border of the Roer Valley graben, in Belgium. Six profile-lines with total length of 13982 m provided information on the 40-600 m depth range, covering Lower Pleistocene to Miocene strata with special emphasis on the Plio-Pleistocene Kieseloolite formation. Data quality depends on near-surface conditions and on degree of deformation in some fault zones, with better results for seismic detonator sources compared to vibroseis sources. The new data confirm the segmented character of the fault system with occurrence of fault bends, relay ramps and branching of overlapping fault sequences, testifying of the strong tectonic activity during the lower Pleistocene. Antiform structures along the Bichterweerd scarp, relaying the Feldbiss to the Geleen fault in the Meuse valley, are presented as a model for the Tertiary evolution of the Bree Uplift.
Frontotemporal brain sagging syndrome is a dementia associated with
hypersomnolence, personality changes, and features of intracranial
hypotension on magnetic resonance imaging. The literature is sparse with
respect to treatment options; many patients simply worsen. We present a case
in which this syndrome responded to lumbar dural reduction surgery.
Postoperative magnetic resonance imaging indicated normalization of brain
sagging and lumbar intrathecal pressure. Although no evidence of
cerebrospinal leak was found, extremely thin dura was noted
intraoperatively, suggesting that a thin and incompetent dura could result
in this low-pressure syndrome. Clinicians who encounter this syndrome should
consider dural reduction surgery as a treatment strategy.
The use of underground geological repositories, such as in radioactive waste disposal (RWD) and in carbon capture (widely known as Carbon Capture and Storage; CCS), constitutes a key environmental priority for the 21st century. Based on the identification of key scientific questions relating to the geophysics, geochemistry and geobiology of geodisposal of wastes, this paper describes the possibility of technology transfer from high-technology areas of the space exploration sector, including astrobiology, planetary sciences, astronomy, and also particle and nuclear physics, into geodisposal. Synergies exist between high technology used in the space sector and in the characterization of underground environments such as repositories, because of common objectives with respect to instrument miniaturization, low power requirements, durability under extreme conditions (in temperature and mechanical loads) and operation in remote or otherwise difficult to access environments.
The Boom Clay Formation of early Oligocene age, which occurs underground in northern Belgium, has been studied intensively for decades as a potential host rock for the disposal of nuclear waste. The goal of the present study is to determine a reference composition for the Boom Clay using both literature methods and methods developed during this work. The study was carried out on 20 samples, representative of the lithological variability of the formation. The bulk-rock composition was obtained by X-ray diffraction using a combined full-pattern summation and singlepeak quantification method. Siliciclastics vary from 27 to 72 wt.%, clay minerals with 25–71 wt.% micas, 0–4 wt.% carbonates, 2–4 wt.% accessory minerals (mainly pyrite and anatase) and 0.5–3.5 wt.% organic matter. This bulk-rock composition was validated independently by majorelement chemical analysis. The detailed composition of the clay-sized fraction was determined by modelling of the oriented X-ray diffraction patterns, using a larger sigma star (σ*) value for discrete smectite than for the other clay minerals. The <2 μm clay mineralogy of the Boom Clay is qualitatively homogeneous; it contains 14–25 wt.% illite, 19–39 wt.% smectite, 19–42 wt.% randomly interstratified illite-smectite with about 65% illite layers, 5–12 wt.% kaolinite, 4–17 wt.% randomly interstratified kaolinite-smectite and 2–7 wt.% chloritic minerals (chlorite, “defective” chlorite and interstratified chlorite-smectite). All modelled clay mineral proportions were verified independently using major-element chemistry and cation exchange capacity measurements. Bulkrock and clay mineral analysis results were combined to obtain the overall detailed quantitative composition of the Boom Clay Formation.
Antidepressants are frequently prescribed but results regarding their efficacy have been equivocal for different spectra of the severity continuum and their side-effects are often burdensome. Non-adherence is a likely consequence. The objective was therefore to examine patients’ trade-offs between the efficacy, side-effects and other drawbacks of antidepressants and whether these trade-offs predicted non-adherence.
Trade-offs from 225 antidepressant users, recruited through community pharmacies, were assessed with an Adaptive Conjoint Analysis (ACA) choice task that was customized to each individual patient. From the estimated utilities, relative importance scores of treatment properties were calculated. Non-adherence was measured through self-report and pharmacy refill data.
Relapse prevention and symptom relief were on average equally important. Side-effects were as important and the side-effect stomach and intestine complaints was on average even slightly more important than relapse prevention and symptom relief. Additional treatment with psychotherapy was preferred by 61% of the patients. A benefit/drawback ratio revealed that 18% of the patients did not consider the efficacy to outweigh the drawbacks. A higher benefit/drawback ratio was associated with a decreased odds of intentional non-adherence [odds ratio (OR) 0.2, 95% confidence interval (CI) 0.07–0.7, Wald = 6.7, p = 0.01).
For nearly one in five patients, the efficacy of antidepressants does not outweigh their drawbacks. Knowing patients’ trade-offs is likely to aid both physicians and patients to identify important treatment preferences, to improve adherence and to make more deliberate decisions on whether or not to continue treatment.
Thus far collaborative stepped care (CSC) studies have not incorporated self-help as a first step.
To evaluate the effectiveness of CSC in the treatment of common mental disorders.
An 8-month cluster randomised controlled trial comparing CSC to care as usual (CAU) (Dutch Trial Register identifier NTR1224). The CSC consisted of a stepped care approach guided by a psychiatric nurse in primary care with the addition of antidepressants dependent on the severity of the disorder, followed by cognitive–behavioural therapy in mental healthcare.
Twenty general practitioners (GPs) and 8 psychiatric nurses were randomised to provide CSC or CAU. The GPs recruited 163 patients of whom 85% completed the post-test measurements. At 4-month mid-test CSC was superior to CAU: 74.7% (n = 68) v. 50.8% (n = 31) responders (P = 0.003). At 8-month post-test and 12-month follow-up no significant differences were found as the patients in the CAU group improved as well.
Treatment within a CSC model resulted in an earlier treatment response compared with CAU.
During the transition from an AGB star to a planetary nebula, a large number of low/intermediate initial mass stars loses its spherical symmetry. The process responsible for that change of morphology is, so far, not well understood. The candidates responsible for shaping these objects are (i) a companion to the star (binary/heavy planet) and its tidal forces, (ii) disk interaction and (iii) magnetic fields - or a combination of these. In particular a binary induced magnetic field is a promising option. To study this we observed the polarization of H2O masers in the known binary pre-Planetary Nebula (pPN) OH231.8+4.2. Our results show a magnetic field B|| of ~45 mG is present in the H2O maser region of this pPN.
Non-Volatile Memories (NVM) integrating silicon nanodots (noted SDs) are considered as an emerging solution to extend Flash memories downscaling. In this alternative memory technology, silicon nanocrystals act as discrete traps for injected charges.
Si-dots were grown by Low Pressure Chemical Vapor Deposition (LPCVD) on top of tunnel oxide. Depending on the pre-growth surface treatment, tunnel oxide surface may present either siloxane or silanol groups. SDs deposition relies on a 2–steps process: nucleation by SiH4 and selective growth with SiH2Cl2.
In a context of technological industrialization, it is of primary importance to develop in-line metrology tools dedicated to Si-dots growth process control. Hence, silicon-dots were observed in top view by using an in-line Critical Dimension Scanning Electron Microscopy CDSEM and their average size and density were extracted from image processing. In addition, Haze measurement, generally used for bare silicon surface characterization, was customized to quantify Si-dots deposition uniformity over the wafer. Finally, Haze value was correlated to Si nanodots density and size determined by CDSEM.
The unipolar resisitive switching properties of MOCVD deposited NiO in Ni/NiO/TiN stacks is reported. The switching quality is defined as function of RESET current and Roff/Ron ratio, and the importance of the Forming current and voltage on these parameters is discussed. The effect of structural stack variations as NiO thickness, Ti doping, and TiN thickness on the switching behavior of NiO is explained by the effect on the forming current and voltage conditions, and on Joule heating dissipation. Thinner NiO films, Ti doping, as well as thicker top electrode improve the switching quality by decreasing the RESET current and increasing the Roff/Ron ratio.
This work addresses non-volatile memories based on metal-oxide polymer diodes. We make a thorough investigation into the static and dynamic behavior. Current-voltage characteristics with varying voltage ramp speed demonstrate that the internal capacitive double-layer structure inhibits the switching at high ramp rates (typical 1000 V/s). This behavior is explained in terms of an equivalent circuit.
It is also reported that there is not a particular threshold voltage to induce switching. Voltages below a particular threshold can still induce switching when applied for a long period of time. The time to switch is longer the lower is the applied voltage and follows an exponential behavior. This suggests that for a switching event to occur a certain amount of charge is required.
Resistive switching properties of silver nanoparticles hosted in an insulating polymer matrix (poly(N-vinyl-2-pyrrolidone) are reported. Planar devices structures using interdigitated gold electrodes were fabricated. These devices have on/off resistance ratio as high as 103 , retention times reaching to months and good endurance cycles. Temperature-dependent measurements show that the charge transport is weakly thermal activated (73 meV) for both states suggesting that nanoparticles will not aggregate into a metallic filament.
Hafnium oxide-based resistive memory devices have been fabricated on copper bottom electrodes. The HfOx active layers in these devices were deposited by atomic layer deposition at 250 °C with tetrakis(dimethylamido)hafnium(IV) as the metal precursor and an O2 plasma as the reactant. Depth profiles of the HfOx by x-ray photoelectron spectroscopy and secondary ion mass spectroscopy revealed a copper concentration on the order of five atomic percent throughout the HfOx film. This phenomenon has not been previously reported in resistive switching literature and therefore may have gone unnoticed by other investigators. The MIM structures fabricated from the HfOx exhibited non-polar behavior, independent of the top metal electrode (Ni, Pt, Al, Au). These results are analogous to the non-polar switching behavior observed by Yang et al.  for intentionally Cu-doped HfOx resistive memory devices. The distinguishing characteristic of the material structure produced in this research is that the copper concentration increases to 60 % in a conducting surface copper oxide layer ~20 nm thick. Lastly, the results from both sweep- and pulse-mode current-voltage measurements are presented and preliminary work on fabricating sub-100 nm devices is summarized.
We investigated the resistive switching behavior of WOx films. WOx was obtained from the thermal oxidation of W thin layers. The parameters under investigation were the influence of the temperature (450-500 °C) and time (30-220 s) used to obtain the WOx on the resistive switching characteristics of Si\W\WOx\Metal_electrode ReRAM cells. The metal top electrodes (TE) tested were Pt, Ni, Cu and Au. The elemental composition and microstructure of the samples were characterized by means of elastic recoil detection analysis (ERD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray reflectivity (XRR).
Electrical measurement of the WOx-based memory elements revealed bipolar and unipolar switching and this depended upon the oxidation conditions and TE selected. Indeed, switching events were observed in WOx samples obtained either at 450 °C or 500 °C in time windows of 180-200 s and 30-60 s, respectively. Pt and Au TE promoted bipolar switching while unipolar behavior was observed with Ni TE only; no switching events were observed with Cu TE. Good switching characteristics seems not related to the overall thickness, crystallinity and composition of the oxide, but on the W6+/W5+ ratio present on the WOx surface, surface in contact with the TE material. Interestingly, W6+/W5+ ratio can be tuned through the oxidation conditions, showing a path for optimizing the properties of the WOx-based ReRAM cells.