Physical and electrochemical evaluation of ATO supported IrO2 catalyst for proton exchange membrane water electrolyser

Antimony doped tin oxide (ATO) was studied as a support material for IrO₂ in proton exchange membrane water electrolyser (PEMWE). Adams fusion method was used to prepare the IrO₂-ATO catalysts. The physical and electrochemical characterisation of the catalysts were carried out using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder conductivity, cyclic voltammetry (CV) and membrane electrode assembly (MEA) polarisation. The BET surface area and electronic conductivity of the supported catalysts were found to be predominantly arisen from the IrO₂. Supported catalyst showed higher active surface area than the pristine IrO₂ in CV analysis with 85% H₃PO₄ as electrolyte. The MEA performance using Nafion®−115 membrane at 80 °C and atmospheric pressure showed a better performance for IrO₂ loading ≥60 wt.% than the pristine IrO₂ with a normalised current density of 1625 mA cm⁻² @1.8 V for the 60% IrO₂-ATO compared to 1341 mA cm⁻² for the pristine IrO₂ under the same condition. The higher performance of the supported catalysts was mainly attributed to better dispersion of active IrO₂ on electrochemically inactive ATO support material, forming smaller IrO₂ crystallites. A 40 wt.% reduction in the IrO₂ was achieved by utilising the support material.

Skin-reducing mastectomy and one-stage implant reconstruction with a myodermal flap: A safe and effective technique in risk-reducing and therapeutic mastectomy

Introduction: Immediate reconstruction following mastectomy for breast cancer has been shown to be oncologically safe and associated with improved psychosocial outcomes for patients. Bostwick described a technique for one-stage implant based reconstruction, combining skin-sparing mastectomy with concurrent reduction of the skin envelope. This report reviews the experience of a single centre using skin-reducing mastectomy and one-stage implant reconstruction in both early stage breast cancer and risk-reducing mastectomy, with specific reference to frequency of complications, implant loss and oncological outcomes.

Methods and results: A retrospective review was undertaken to identify women who had undergone skin-reducing mastectomy and one-stage implant reconstruction using a de-epithelialised dermal flap, between October 2008 and October 2012. One hundred and four consecutive mastectomies, with reconstruction, were performed by two surgeons on 64 patients. No complications were seen in 43.8% of patients. At three months, four implants were lost (3.8% of breast reconstructions, 6.3% of patients), due to either peri-implant infection or mastectomy skin flap necrosis. One patient required unplanned return to theatre for evacuation of a haematoma. Minor mastectomy skin flap necrosis was seen in 10 breasts (9.6% of reconstructed breasts) and superficial wound infection in 8 breasts (7.7% of reconstructed breasts). All of these complications were managed conservatively and none required operative intervention. At a median follow up of 35 months (4-53 months) there had been one episode of ipsilateral axillary nodal recurrence.

Conclusion: One-stage implant reconstruction using a myo-dermal flap technique following skin-reducing mastectomy is safe and should be considered in selected patients. Most complications are minor and will resolve with conservative management. Major complications such as implant failure or immediate reoperation, were relatively uncommon (6.3% patients, 3.8% of reconstructed breasts). Early follow-up suggests that oncological outcomes are satisfactory, but longer follow-up is required to substantiate this. (C) 2013 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Investigation of supported IrO2 as electrocatalyst for the oxygen evolution reaction in proton exchange membrane water electrolyser

Indium tin oxide (ITO) was used as a support for IrO2 catalyst in the oxygen evolution reaction. IrO2 nanoparticles were deposited in various loading on commercially available ITO nanoparticle, 17–28 nm in size using the Adam's fusion method. The prepared catalysts were characterised using X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The BET surface area of the support (35 m2/g) was 3 times lower than the unsupported IrO2 (112.7 m2/g). The surface area and electronic conductivity of the catalysts were predominantly contributed by the IrO2. The supported catalysts were tested in a membrane electrode assembly (MEA) for electrolyser operation. The 90% IrO2-ITO gave similar performance (1.74 V@1 A/cm2) to that of the unsupported IrO2 (1.73 V@1 A/cm2) in the MEA polarisation test at 80 °C with Nafion 115 membrane which was attributed to a better dispersion of the active IrO2 on the electrochemically inactive ITO support, giving rise to smaller catalyst particle and thereby higher surface area. Large IrO2 particles on the support significantly reduced the electrode performance. A comparison of TiO2 and ITO as support material showed that, 60% IrO2 loading was able to cover the support surface and giving sufficient conductivity to the catalyst.

Supported decision making: a review of the international literature

Supported decision making (SDM) refers to the process of supporting people, whose decision making ability may be impaired, to make decisions and so promote autonomy and prevent the need for substitute decision making. There have been developments in SDM but mainly in the areas of intellectual disabilities and end-of-life care rather than in mental health. The main aim of this review was to provide an overview of the available evidence relevant to SDM and so facilitate discussion of how this aspect of law, policy and practice may be further developed in mental health services. The method used for this review was a Rapid Evidence Assessment which involved: developing appropriate search strategies; searching relevant databases and grey literature; then assessing, including and reviewing relevant studies. Included studies were grouped into four main themes: studies reporting stakeholders’ views on SDM; studies identifying barriers to the implementation of SDM; studies highlighting ways to improve implementation; and studies on the impact of SDM. The available evidence on implementation and impact, identified by this review, is limited but there are important rights-based, effectiveness and pragmatic arguments for further developing and researching SDM for people with mental health problems.

Effect of shotpeening on sliding wear and tensile behavior of titanium implant alloys

Titanium has good biocompatibility and so its alloys are used as implant materials, but they suffer from having poor wear resistance. This research aims to improve the wear resistance and the tensile strength of titanium alloys potentially for implant applications. Titanium alloys Ti–6Al–4V and Ti–6Al–7Nb were subjected to shotpeening process to study the wear and tensile behavior. An improvement in the wear resistance has been achieved due to surface hardening of these alloys by the process of shotpeening. Surface microhardness of shotpeened Ti–6Al–4V and Ti–6Al–7Nb alloys has increased by 113 and 58 HV(0.5), respectively. After shotpeening, ultimate tensile strength of Ti–6Al–4V increased from 1000 MPa to 1150 MPa, higher than improvement obtained for heat treated titanium specimens. The results confirm that shotpeening pre-treatment improved tensile and sliding wear behavior of Ti–6Al–4V and Ti–6Al–7Nb alloys. In addition, shotpeening increased surface roughness.

A simple and low-cost method for the preparation of self-supported TiO2-WO3 ceramic heterojunction wafers

Robust, bilayer heterojunction photodiodes of TiO₂-WO₃ were prepared successfully by a simple, low-cost powder pressing technique followed by heat-treatment. Exclusive photoirradiation of the TiO₂ side of the photodiode resulted in a rapid colour change (dark blue) on the WO₃ surface as a result of reduction of W⁶⁺ to W⁵⁺ (confirmed by X-ray photoelectron spectroscopy). This colour was long lived and shown to be stable in a dry environment in air for several hours. A similar photoirradiation experiment in the presence of a mask showed that charge transfer across the heterojunction occurred approximately normal to the TiO₂ surface, with little smearing out of the mask image. As a result of the highly efficient vectorial charge separation, the photodiodes showed a tremendous increase in photocatalytic activity for the degradation of stearic acid, compared to wafers of the respective individual materials when tested separately.

Implant-retained overdentures did not have a significant improvement in dietary intake

DESIGN: Randomised controlled trial.

INTERVENTION: Patients aged 65 or above edentate for a minimum of five years, with sufficient bone for two implants in the anterior mandible, were recruited. Those with systemic disease that contraindicated implants or had a low mini-mental state evaluation score were excluded. Patients in both groups had a standard maxillary complete denture fabricated. Patients randomised to the treatment group received a two-implant mandibular overdenture while those in the control group received a standard mandibular complete denture. Three 24-hour dietary recalls were collected by telephone interviews at baseline and at 12 months.

RESULTS: 255 patients were randomised: 128 received a standard complete denture (CD) and 127 a two-implant mandibular overdenture (IOD). 127 patients were available at 12-month follow up, 114 in the CD group and 103 in the IOD group. No significant between-group differences were found.

CONCLUSIONS: Although there is much evidence supporting the adoption of two-implant mandibular overdenture (IOD) treatment as the standard of care for edentate patients, this evidence does not include an improvement in dietary intake at one year for medically healthy independent edentate elders when given no specific dietary counselling.

Do removable dental prosthesis have an impact on tooth loss?

DESIGN: A multi-centre randomised controlled study in 14 dental schools. This report is an interim analysis at 3 years.

INTERVENTION: Patients were allocated to either the Removable dental prosthesis group (RPD)-109 patients or the no prosthesis group (SDA) -106 patients. Patients had to be older than 35 years with no molars in the study jaw. Follow-up visits were scheduled at 4 to 8 wks (baseline), at 6 months, and at 1, 2, 3, 4, and 5 yrs after treatment.

OUTCOME MEASURE: Time to loss of first tooth following intervention or no intervention.

RESULTS: 81 patients received a RDP and 69 patients received no treatment in the end. This is a reduction of 26% and 35% respectively from the time when they were randomised to the two groups. Tooth loss occurred in 13 of the RDP group (16% of those who received the RDP, 12% of those allocated to the group at the start) with 5 of these being in the study jaw and 8 in the opposing jaw. Tooth loss occurred in 9 of the SDA group (13% of those who received SDA, 9% of those who were allocated to the group at the start) with 5 in the study jaw and 4 in the opposing jaw. The respective Kaplan-Meier survival rates at 38 months were 0.83 (95% CI: 0.74-0.91) in the RDP group and 0.86 (95% CI: 0.78-0.95) in the SDA group.

CONCLUSIONS: The difference in tooth loss at three years between patients treated with RDP and those not treated with RDP was not significant.

An international comparison of legal frameworks for supported and substitute decision-making in mental health services

There have been important recent developments in law, research, policy and practice relating to supporting people with decision-making impairments, in particular when a person’s wishes and preferences are unclear or inaccessible. A driver in this respect is the United Nations Convention on the Rights of Persons with Disabilities (CRPD); the implications of the CRPD for policy and professional practices are currently debated. This article reviews and compares four legal frameworks for supported and substitute decision-making for people whose decision-making ability is impaired. In particular, it explores how these frameworks may apply to people with mental health problems. The four jurisdictions are: Ontario, Canada; Victoria, Australia; England and Wales, United Kingdom (UK); and Northern Ireland, UK. Comparisons and contrasts are made in the key areas of: the legal framework for supported and substitute decision-making; the criteria for intervention; the assessment process; the safeguards; and issues in practice. Thus Ontario has developed a relatively comprehensive, progressive and influential legal framework over the past thirty years but there remain concerns about the standardisation of decision-making ability assessments and how the laws work together. In Australia, the Victorian Law Reform Commission (2012) has recommended that the six different types of substitute decision-making under the three laws in that jurisdiction, need to be simplified, and integrated into a spectrum that includes supported decision-making. In England and Wales the Mental Capacity Act 2005 has a complex interface with mental health law. In Northern Ireland it is proposed to introduce a new Mental Capacity (Health, Welfare and Finance) Bill that will provide a unified structure for all substitute decision-making. The discussion will consider the key strengths and limitations of the approaches in each jurisdiction and identify possible ways that further progress can be made in law, policy and practice.