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Electroconvulsive therapy (ECT) is recommended in treatment guidelines as an efficacious therapy for treatment-resistant depression. However, it has been associated with loss of autobiographical memory and short-term reduction in new learning.
To provide clinically useful guidelines to aid clinicians in informing patients regarding the cognitive side-effects of ECT and in monitoring these during a course of ECT, using complex data.
A Committee of clinical and academic experts from Australia and New Zealand met to the discuss the key issues pertaining to ECT and cognitive side-effects. Evidence regarding cognitive side-effects was reviewed, as was the limited evidence regarding how to monitor them. Both issues were supplemented by the clinical experience of the authors.
Meta-analyses suggest that new learning is impaired immediately following ECT but that group mean scores return at least to baseline by 14 days after ECT. Other cognitive functions are generally unaffected. However, the finding of a mean score that is not reduced from baseline cannot be taken to indicate that impairment, particularly of new learning, cannot occur in individuals, particularly those who are at greater risk. Therefore, monitoring is still important. Evidence suggests that ECT does cause deficits in autobiographical memory. The evidence for schedules of testing to monitor cognitive side-effects is currently limited. We therefore make practical recommendations based on clinical experience.
Despite modern ECT techniques, cognitive side-effects remain an important issue, although their nature and degree remains to be clarified fully. In these circumstances it is useful for clinicians to have guidance regarding what to tell patients and how to monitor these side-effects clinically.
The term ‘mood stabiliser’ is ill-defined and lacks clinical utility. We propose a framework to evaluate medications and effectively communicate their mood stabilising properties – their acute and prophylactic efficacy across the domains of mania and depression. The standardised framework provides a common definition to facilitate research and clinical practice.
Declaration of interest
The Treatment Algorithm Group (TAG) was supported logistically by Servier who provided financial assistance with travel and accommodation for those TAG members travelling interstate or overseas to attend the meeting in Sydney (held on 18 November 2017). None of the committee were paid to participate in this project and Servier have not had any input into the content, format or outputs from this project.
Renin is essential for renal development and in adult kidneys vitamin D deficiency increases renin gene expression. We aimed to determine whether maternal vitamin D deficiency upregulates fetal renal renin expression, and if this is sustained. We also examined growth and the long-term renal effects in offspring on a normal diet. Female Sprague–Dawley rats in UVB-free housing were fed either vitamin D deficient chow (DEF) or normal chow from 4 weeks and mated with vitamin D replete males at 10 weeks. Fetuses were collected at E20 or dams littered and the pups were weaned onto normal chow. Kidney mRNA levels for renin, (pro)renin receptor [(P)RR], transforming growth factor β 1 (TGF-β1), and nephrin were determined in E20 fetuses and in male offspring at 38 weeks. Renal function was assessed at 33 weeks (24 h, metabolic cage) in both sexes. Renal mRNA expression was upregulated for renin in fetuses (P < 0.05) and was almost doubled in adult male offspring from DEF dams (P < 0.05). Adult males had reduced creatinine clearance, solute excretion and a suppressed urinary sodium-to-potassium ratio (P < 0.05). Female adult DEF offspring drank more and excreted more urine (P < 0.05) but creatinine clearance was not impaired. We conclude that maternal vitamin D depletion upregulates fetal renal renin gene expression and this persists into adulthood where, in males only, there is evidence of sodium retention and compromised renal function. Importantly these effects occurred despite the animals being on a normal diet from the time of weaning onwards.
An Al 5083 alloy with a bimodal grain size has been previously synthesized using a low-temperature milling process and consolidation via cold isostatic pressing (CIP). This material has been shown to exhibit greatly improved strength when compared to conventional aluminum alloys. Additionally, this material has shown sensitivity to test conditions. In this work, we studied the effects of temperature on the strain rate sensitivity of this material by examining its elastic and plastic properties though uniaxial tension tests conducted under a variety of conditions at temperatures up to 473 K. Serrated stress-strain curves were observed, indicating dynamic strain aging. Strain rate sensitivity was found to depend non-monotonically on the test temperature.
The objective of this research was to assess current patterns of hospital antibiotic prescribing in Northern Ireland and to determine targets for improving the quality of antibiotic prescribing. A point prevalence survey was conducted in four acute teaching hospitals. The most commonly used antibiotics were combinations of penicillins including β-lactamase inhibitors (33·6%), metronidazole (9·1%), and macrolides (8·1%). The indication for treatment was recorded in 84·3% of the prescribing episodes. A small fraction (3·9%) of the surgical prophylactic antibiotic prescriptions was for >24 h. The results showed that overall 52·4% of the prescribed antibiotics were in compliance with the hospital antibiotic guidelines. The findings identified the following indicators as targets for quality improvement: indication recorded in patient notes, the duration of surgical prophylaxis and compliance with hospital antibiotic guidelines. The results strongly suggest that antibiotic use could be improved by taking steps to address the identified targets for quality improvement.
The influence of colostrum-derived antibody to louping-ill virus on the course of experimental infection was investigated in lambs. Lambs that had high titres of antibody were refractory to infection. Lambs that had low titres of antibody did not develop a viraemia but either showed an antibody reaction or were sensitized as judged by the immune response, which was typical of an anamnestic response, after rechallenge. Animals that had no antibody 34–20 days before challenge had either no or very slight viraemia, but did develop an antibody response with titres as high as those of control lambs by day 21. Lambs that had been negative for longer periods responded in a similar fashion to controls.
These findings are discussed in relation to the occurrence of disease in lambs kept in louping-ill endemic areas. It is concluded that in such areas infections of lambs are likely to be of minor importance as a cause of mortality and of little epidemiological significance.
Nb-Ti-Ni alloy is one of the candidates for hydrogen permeation membranes. The hydrogen permeability of a membrane depends on its thickness, and mechanical properties such as the fracture toughness of the membrane are important to ensure reliability and durability. In the present work, micro-mechanical tests have been carried out for melt-spun Nb-Ti-Ni thin films consisting of amorphous and nano-crystalline phases. The relationship between the mechanical properties of the melt-spun films and the microstructural changes occurring in the films due to heat treatment has been also discussed. The Nb-Ti-Ni alloy thin films were prepared by the melt-spun technique and then heat-treated at 873-1173 K. Micro-sized cantilever specimens with dimensions of 10 × 10 × 50 μm3 were prepared by focused ion beam (FIB) machining. Fracture tests were carried out using a mechanical testing machine for the micro-sized specimens; the testing machine was developed by us. In addition, microstructures were observed by transmission electron microscopy (TEM). The fracture toughness (KQ) value decreased up to 823 K, and it increased above 1173 K. The specimen heat-treated above 1173 K showed ductile fracture. The fracture morphology of the specimen heat-treated up to 1023 K showed grain boundary fracture characteristics, and that of the specimen heat-treated at 1173 K changed to transgranular fracture.
We used thickness gradients for high throughput optimization of adhesion in film stacks. The idea is based on the so-called superlayer test where a top layer under high compression exerts a load onto the lower interfaces and may cause delamination and buckling. Thus, on one hand, the thickness gradient of the superlayer results in the gradient of the load. On the other hand, the adhesion gradient can be realized by changing the thickness of an adhesion enhancer (or an adhesion reducer). When applied in two perpendicular directions (cross-gradient), the gradient of the superlayer in one direction and of the adhesion enhancer in the other, the plane of the sample represents a map where the line of delamination relates the interfacial toughness to the thickness of the enhancer.
In our tests we used Mo superlayers under compressive stress of the order of ˜1.5 GPa on a Si wafer with a native oxide. The adhesion reduction was observed with this methodology when Ag layer up to 10 nm thick was deposited onto the substrate prior to Mo deposition. The delamination occurred at Ag thicknesses starting from ˜6 nm. This thickness of Ag corresponds to the islands coalescence and formation of a continuous film which immediately results in adhesion reduction. The other test was performed with a step gradient of Ti enhancer placed under a 10 nm thick Ag layer in otherwise the same arrangement. A single test showed that 2.8 Å of Ti was sufficient to improve the adhesion between Ag and SiOx by several times.
The study of indentation responses of rate-dependent (viscoplastic or creeping) solids has generally focused on the relationship between indentation hardness and an effective strain rate, which can be defined from a similarity transformation of the governing equations. The strain rate sensitivity exponent can be determined from the slope of a log-log plot of the hardness versus effective strain rate, while determining other constitutive parameters requires a knowledge of the relationship between contact size, shape, and indentation depth. In this work, finite element simulations have shown that the effects of non-axisymmetric contact and crystallography are generally negligible. Theoretical predictions agree well with real nanoindentation measurements on amorphous selenium when tested above glass transition temperature, but deviate quite significantly for experiments on high-purity indium, coarse-grained aluminum, and nanocrystalline nickel. Such a discrepancy is likely to result from the transient creep behavior.
The thermal effect on the nanofluidic behaviors in a nanoporous silica gel is investigated experimentally. When a nanoporous silica gel is modified by silyl groups, its surface becomes hydrophobic. A sufficiently high external pressure must be applied to overcome the capillary effect; otherwise liquid infiltration could not occur. The formation and the disappearance of a solid–liquid interface are employed for energy storage or dissipation. When the hydrophobic surface of nanoporous silica gel is decomposed at various temperatures, the organic surface layers can be deactivated. As a result, the degree of hydrophobicity, which can be measured by the liquid infiltration pressure, is lowered. The infiltration and defiltration behaviors of liquid are dependent on the controlled by the decomposition-treatment temperature.
The paper reports new experimental results describing properties and microstructure of nanocrystalline metals. Nano- and sub-micron aluminium has been produced by hydrostatic extrusion at ambient tempearture. The structures have been quantified in terms of size of grains and misorientation of the grain boundaries. Different average size of grains, variable normalized width of grain size distribution and changing grain boundary misorientation distribution functions have been revealed depending on processing parameters. The results of the tensile tests showed that the average grain size, grain size distribution and the distribution function of misorientation angles influence the flow stress of obtained nano-metals. In order to explain the observed difference in the properties of nano- and micro-sized aluminium alloys, a Finite Element Method models have been developed, which assumes that both grain boundaries and grain interiors may accommodated elastic and non-linear plastic deformation. These models assumed true geometry of grains (which differed in size and shape). Also, variable mechanical properties of grain boundaries have been taken into account (elastic modulus, yield strength and work hardening rate). The results of modelling explain in a semi-quantitative way macroscopic deformation of nano-crystalline aggregates. In particular, they illustrate the importance of the interplay between properties of grain boundaries and grain interiors in elastic and plastic regime.
The objective of this study is to characterize the nanoparticle dispersion and to investigate its effect on the surface mechanical properties of nanoparticle-polymer systems. Two types of TiO2 nanoparticles were chosen to mix in two polymeric matrices: solvent-borne acrylic urethane (AU) and water-borne butyl-acrylic styrene latex (latex) coatings. Nanoparticle dispersion was characterized using laser scanning confocal microscopy. Overall, Particle A (PA, without surface treatment) dispersed better than Particle B (PB, organic treatment) in both systems. The AU-PA system exhibited the best dispersion of the four systems, however PB forms big clusters in both of the matrices. Surface mechanical properties, such as surface modulus at micron and sub-micron length scales were determined from depth sensing indentation equipped with a pyramidal tip or a conical tip. The surface mechanical properties were strongly affected by the dispersion of nanoparticle clusters, and a good correlation was found between dispersion of nanoparticle clusters near surface and the modulus-depth mapping using a pyramid tip.
This paper presents molecular dynamics simulations of shear-coupled migration of tilt boundaries pinned by triple junctions in a simple model structure of columnar grains of different sizes. Simulations are for copper at 300 K. The phenomenon is of interest as a possible explanation of the Hall-Petch relationship breakdown in nano-grained polycrystals deformed at high or moderate strain rate and low-temperature.
In order to perform a systematic study of the interaction between grain boundaries (GBs) and dislocations using molecular dynamics (MD), several tools need to be available. A combination of computational geometry and MD was used to build the foundations of what we call a virtual laboratory. First, an algorithm to generate GBs on face-centered cubic bicrystals was developed. Two crystals with different orientations are placed together. Then, by applying “microscopic” rigid body translations along the GB plane to one of the crystals and removing overlapping atoms, a set of initial configurations is sampled and a minimum energy configuration is found. Second, to classify the geometry of the GBs a local symmetry type (LST) describing the angular environment of each atom is calculated. It is found that for a given relaxed GB the number of atoms with different LSTs is not very large and that it is possible to find unique geometrical patterns in each GB. For instance, the LSTs of two GBs having the same “macroscopic” configuration but different “microscopic” degrees of freedom can be dissimilar: the configurations with higher GB energy tend to have a higher number of atoms with different LSTs. Third, edge dislocations are introduced into the bicrystals. We see that full edge dislocations split into Shockley partials. Finally, by loading the bicrystals with tensile stresses the edge dislocations are put into motion. Various examples of dislocation-GB interactions in Cu are presented.
While the low thermal conductivities of silica aerogels have made them of interest to the aerospace community as lightweight thermal insulation, the application of conformal polymer coatings to these gels increases their strength significantly, making them potentially useful as structural materials as well. In this work we perform multiscale computer simulations to investigate the tensile and compressive strain behavior of silica and polymer-coated silica aerogels.
Aerogels are made up of clusters of interconnected particles of amorphous silica of less than bulk density. We simulate gel nanostructure using a Diffusion Limited Cluster Aggregation (DLCA) procedure, which produces aggregates that exhibit fractal dimensions similar to those observed in real aerogels. We have previously found that model gels obtained via DLCA exhibited stress-strain curves characteristic of the experimentally observed brittle failure. However, the strain energetics near the expected point of failure were not consistent with such failure. This shortcoming may be due to the fact that the DLCA process produces model gels that are lacking in closed-loop substructures, compared with real gels. Our model gels therefore contain an excess of dangling strands, which tend to unravel under tensile strain, producing non-brittle failure. To address this problem, we have incorporated a modification to the DLCA algorithm that specifically produces closed loops in the model gels.
We obtain the strain energetics of interparticle connections via atomistic molecular statics, and abstract the collective energy of the atomic bonds into a Morse potential scaled to describe gel particle interactions. Polymer coatings are similarly described.
We apply repeated small uniaxial strains to DLCA clusters, and allow relaxation of the center eighty percent of the cluster between strains. The simulations produce energetics and stress-strain curves for looped and nonlooped clusters, for a variety of densities and interaction parameters.
The effect of alloying elements Ta, Mo, W, Cr, Re, Ru, Co, and Ir on the elastic properties of both γ-Ni and γ′-Ni3Al is studied by first-principles method. Results for lattice properties, elastic moduli and the ductile/brittle behaviors are all presented. Our calculated values agree well with the existing experimental observations. Results show all the additions decrease the lattice misfit between and γ′ phases. Different alloying elements are found to have different effect on the elastic moduli of γ-Ni. Whereas all the alloying elements slightly increase the moduli of γ′-Ni3Al expect Co. Both of the two phases are becoming more brittle with alloying elements, but Co is excepted. The electronic structures of γ′ phase alloyed with different elements are provided as example to elucidate the different strengthening mechanisms.
Transition pathway sampling was carried out for homogeneous dislocation nucleation in perfect crystal Si. The sampling algorithm employed was Nudged Elastic Band method. Results obtained were compared with corresponding results for Cu. The stress and activation barrier ranges were found to be much higher for Si than those reported for Cu. The results also showed that while for lower values of resolved shear stress the dislocation embryo approaches that of a perfect dislocation, for higher resolved shear stress values the embryo is far from perfect. That is, the shear displacement of most particles is considerably less than the Burger’s vector. This investigation also demonstrated for the first time that Athermal shear stress for homogeneous dislocation nucleation in Si does not exist, as the crystal undergoes twinning at such high stresses.