Cost-effectiveness of guided self-help treatment for recurrent binge eating.

Objective: Adoption of effective treatments for recurrent binge-eating disorders depends on the balance of costs and benefits. Using data from a recent randomized controlled trial, we conducted an incremental cost-effectiveness analysis (CEA) of a cognitive–behavioral therapy guided self-help intervention (CBT–GSH) to treat recurrent binge eating compared to treatment as usual (TAU). Method: Participants were 123 adult members of an HMO (mean age = 37.2 years, 91.9% female, 96.7% non-Hispanic White) who met criteria for eating disorders involving binge eating as measured by the Eating Disorder Examination (C. G. Fairburn & Z. Cooper, 1993). Participants were randomized either to treatment as usual (TAU) or to TAU plus CBT–GSH. The clinical outcomes were binge-free days and quality-adjusted life years (QALYs); total societal cost was estimated using costs to patients and the health plan and related costs. Results: Compared to those receiving TAU only, those who received TAU plus CBT–GSH experienced 25.2 more binge-free days and had lower total societal costs of $427 over 12 months following the intervention (incremental CEA ratio of ?$20.23 per binge-free day or ?$26,847 per QALY). Lower costs in the TAU plus CBT–GSH group were due to reduced use of TAU services in that group, resulting in lower net costs for the TAU plus CBT group despite the additional cost of CBT–GSH. Conclusions: Findings support CBT–GSH dissemination for recurrent binge-eating treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of heat treatment on microstructure and microhardness evolution in a Ti–6Al–4V alloy processed by high-pressure torsion

A Ti–6Al–4V alloy was heat-treated to give two types of microstructures with different volume fraction of equiaxed α phase and lamellar (α + β) microstructure. Disks were cut from the heat-treated rods and processed by quasi-constrained high-pressure torsion (HPT) at room temperature with an applied pressure of 6.0 GPa and torsional straining from 1/4 to 20 turns. The results show that there is a gradual evolution of homogeneity in microhardness and grain size with increasing numbers of revolutions in HPT such that the microhardness values attain a maximum constant value across the disk after processing by HPT for 10 turns and the measured equilibrium grain sizes after 20 turns are ~130 nm in Ti64-1 and ~70 in Ti64-2. The results show also that a larger fraction of lamellar (α + β) in the microstructure of Ti–6Al–4V leads to a higher hardenability after processing by HPT.     

A comparison of microstructures and mechanical properties in a Cu–Zr alloy processed using different SPD techniques

Experiments were conducted to evaluate the microstructures and mechanical properties of a Cu–0.1 % Zr alloy processed using two different techniques of severe plastic deformation: equal-channel angular pressing (ECAP) and high-pressure torsion (HPT). The samples were processed at room temperature through ECAP for eight passes or through HPT for 10 turns. The results show HPT is more effective both in refining the grains and in producing a large fraction of grain boundaries having high angles of misorientation. Both procedures produce reasonably homogeneous hardness distributions but the average hardness values were higher after HPT. In tensile testing at 673 K, the highest strength and ductility was achieved after processing by HPT. This is attributed to the grain stability and high fraction of high-angle grain boundaries produced in HPT.     

Stability of the ultrafine-grained microstructure in silver processed by ECAP and HPT

The high-temperature thermal stability of the ultrafine-grained (UFG) microstructures in low stacking fault energy silver was studied by differential scanning calorimetry (DSC). The UFG microstructures were achieved by equal-channel angular pressing (ECAP) and high-pressure torsion (HPT) at room temperature (RT). The defect structure in the as-processed samples was examined by electron microscopy and X-ray line profile analysis. The stored energy calculated from the defect densities was compared to the heat released during DSC. The sum of the energies stored in grain boundaries and dislocations in the ECAP-processed samples agreed with the heat released experimentally within the experimental error. The temperature of the DSC peak maximum decreased while the released heat increased with increasing numbers of ECAP passes. The released heat for the specimen processed by one revolution of HPT was much smaller than after 4–8 passes of ECAP despite the 2 times larger dislocation density measured by X-ray line profile analysis. This dichotomy was caused by the heterogeneous sandwich-like microstructure of the HPT-processed disk: about 175 μm wide surface layers on both sides of the disk exhibited a UFG microstructure while the internal part was recrystallized, thereby yielding a relatively small released heat.     

Tribology testing of ultrafine-grained Ti processed by high-pressure torsion with subsequent coating

A grade 2 pure Ti was processed by high-pressure torsion (HPT) under 3.0 GPa for 10 revolutions to achieve an improved strength. Wear tests revealed that HPT only slightly improved the wear resistance of pure Ti. Subsequently, a TiN coating with a thickness of 2.5 μm was deposited on different Ti substrates to improve the wear resistance. Both indentation and scratch testing demonstrated a much improved load-bearing capacity when ultrafine-grained Ti was chosen as the substrate compared with coarse-grained Ti. All results indicate that pure Ti processed by HPT, when combined with a subsequent coating, represents a good candidate material for bio-implant applications.     

Recent developments in modelling of microhardness saturation during SPD processing of metals and alloys

Ultrafine-grained and even nanostructured materials can be fabricated using severe plastic deformation to ultra-high strains in equal-channel angular pressing (ECAP), high-pressure torsion (HPT), machining and their combinations, such as machining of ECAP specimens, HPT of ECAP billets and HPT of machining chips. This report presents recent results of investigations of the microstructures and microtextures of pure copper, nickel and aluminium subjected to different deformation processes to ultimately high imposed strains. A comparison of the microstructure, dislocation density and microhardness developed during combinations of different strain paths is performed. All characteristics were analysed by X-ray, transmission and scanning electron microscopy, and electron backscatter diffraction (EBSD). The influence of different processing routes is discussed in terms of the accumulated strain and microstructure refinement. The saturation in grain refinement is examined with reference to the recovery taking place during ultra-high strain deformation. A phenomenological model based on the Voce equation is applied for fitting parameters based on the experimental data and this is suggested for a prediction of microhardness evolution for pure metals (Ag, Au) and Cu-based (Zn, Al) alloys.     

Using X-ray microbeam diffraction to study the long-range internal stresses in aluminum processed by ECAP

Aluminum alloy 1050 was processed by equal-channel angular pressing (ECAP) using a single pass (equivalent uniaxial strain of about 0.88). Long-range internal stresses (LRISs) were assessed in the grain/subgrain interiors using X-ray microbeam diffraction to measure the spacing of {5 3 1} planes, with normals oriented approximately +27.3°, +4.9° and ?17.5° off the pressing (axial) direction. The results are consistent with mechanical analysis that suggests the maximum tensile plastic-strain after one pass is expected for +22.5°, roughly zero along the pressing axis, and maximum compressive strain for the ?67.5° direction. The magnitude of the measured maximum compressive long-range internal stress is about 0.13σ_a (applied stress) in low-dislocation regions within the grain/subgrain interiors. This work is placed in the context of earlier work where convergent beam electron diffraction was used to analyze LRISs in close proximity to the deformation-induced boundaries. The results are complementary and the measured stresses are consistent with a composite model for long-range internal stresses.     

Evaluating the influence of pressure and torsional strain on processing by high-pressure torsion

Tests were conducted on an Al-6061 alloy to evaluate the separate effects of the applied pressure and the torsional straining in processing by high-pressure torsion (HPT). The values of the Vickers microhardness were measured after processing and plotted both linearly across the diameters of the disks and as three-dimensional representations. The measurements show that the applied pressure increases the hardness in the absence of torsional straining. In the presence of a pressure and torsional straining, the hardness values are high at the edges of the disk but lower in the central region. There is a gradual evolution toward a hardness homogeneity with increasing numbers of HPT revolutions. The hardness values at the edges of the disks are reasonably independent of the applied pressure but the extent of this region of high hardness depends upon both the applied pressure and the numbers of turns in the HPT processing.     

Characterization of epitaxial GaAs MOS capacitors using atomic layer-deposited TiO2/Al2O3 gate stack: study of Ge auto-doping and p-type Zn doping

Few-wall carbon nanotubes were synthesized by methane/acetylene decomposition over bimetallic Fe-Mo catalyst with MgO (1:8:40) support at the temperature of 900°C. No calcinations and reduction pretreatments were applied to the catalytic powder. The transmission electron microscopy investigation showed that the synthesized carbon nanotubes [CNTs] have high purity and narrow diameter distribution. Raman spectrum showed that the ratio of G to D band line intensities of I _G/I _D is approximately 10, and the peaks in the low frequency range were attributed to the radial breathing mode corresponding to the nanotubes of small diameters. Thermogravimetric analysis data indicated no amorphous carbon phases. Experiments conducted at higher gas pressures showed the increase of CNT yield up to 83%. M?ssbauer spectroscopy, magnetization measurements, X-ray diffraction, high-resolution transmission electron microscopy, and electron diffraction were employed to evaluate the nature of catalyst particles.     

Fate of Zinc Oxide Nanoparticles during Anaerobic Digestion of Wastewater and Post-Treatment Processing of Sewage Sludge

The rapid development and commercialization of nanomaterials will inevitably result in the release of nanoparticles (NPs) to the environment. As NPs often exhibit physical and chemical properties significantly different from those of their molecular or macrosize analogs, concern has been growing regarding their fate and toxicity in environmental compartments. The wastewater-sewage sludge pathway has been identified as a key release pathway leading to environmental exposure to NPs. In this study, we investigated the chemical transformation of two ZnO-NPs and one hydrophobic ZnO-NP commercial formulation (used in personal care products), during anaerobic digestion of wastewater. Changes in Zn speciation as a result of postprocessing of the sewage sludge, mimicking composting/stockpiling, were also assessed. The results indicated that "native" Zn and Zn added either as a soluble salt or as NPs was rapidly converted to sulfides in all treatments. The hydrophobicity of the commercial formulation retarded the conversion of ZnO-NP. However, at the end of the anaerobic digestion process and after postprocessing of the sewage sludge (which caused a significant change in Zn speciation), the speciation of Zn was similar across all treatments. This indicates that, at least for the material tested, the risk assessment of ZnO-NP through this exposure pathway can rely on the significant knowledge already available in regard to other "conventional" forms of Zn present in sewage sludge.