Si photocathode with Ag-supported dendritic Cu catalyst for CO2 reduction

Si photocathodes integrated with Ag-supported dendritic Cu catalysts are used to perform light-driven reduction of CO2 to C2 and C3 products in aqueous solution. A back illumination geometry with an n-type Si absorber was used to permit the use of absorbing metallic catalysts. Selective carrier collection was accomplished by a p+ implantation on the illumination side and an n+ implantation followed by atomic layer deposition of TiO2 on the electrolyte site. The Ag-supported dendritic Cu CO2 reduction catalyst was formed by evaporation of Ag followed by high-rate electrodeposition of Cu to form a high surface area structure. Under simulated 1 sun illumination in 0.1 M CsHCO3 saturated with CO2, the photovoltage generated by the Si (∼600 mV) enables C2 and C3 products to be produced at -0.4 vs. RHE. Texturing of both sides of the Si increases the light-limited current density, due to reduced reflection on the illumination side, and also deceases the onset potential. Under simulated diurnal illumination conditions photocathodes maintain over 60% faradaic efficiency to hydrocarbon and oxygenate products (mainly ethylene, ethanol, propanol) for several days. After 10 days of testing, contamination from the counter electrode is observed, which causes an increase in hydrogen production. This effect is mitigated by a regeneration procedure which restores the original catalyst selectivity. A tandem, self-powered CO2 reduction device was formed by coupling a Si photocathode with two series-connected semitransparent CH3NH3PbI3 perovskite solar cells, achieving an efficiency for the conversion of sunlight to hydrocarbons and oxygenates of 1.5% (3.5% for all products)

A critical role for the loop region of the basic helix–loop–helix/leucine zipper protein Mlx in DNA binding and glucose-regulated transcription

The carbohydrate response element (ChoRE) is a cis-acting sequence found in the promoters of genes induced transcriptionally by glucose. The ChoRE is composed of two E box-like motifs that are separated by 5 bp and is recognized by two basic helix–loop–helix/leucine zipper (bHLH/LZ) proteins, ChREBP and Mlx, which heterodimerize to bind DNA. In this study, we demonstrate that two ChREBP/Mlx heterodimers interact to stabilize binding to the tandem E box-like motifs in the ChoRE. Based on a model structure that we generated of ChREBP/Mlx bound to the ChoRE, we hypothesized that intermolecular interactions between residues within the Mlx loop regions of adjacent heterodimers are responsible for stabilizing the complex. We tested this hypothesis by preparing Mlx variants in which the loop region was replaced with that of another family member or mutated at several key residues. These Mlx variants retained their ability to bind to a single perfect E-box motif as a heterodimer with ChREBP, but no longer bound to the ChoRE nor supported glucose responsive activity. In summary, our results support a model in which the loop regions of Mlx play an important functional role in mediating the coordinate binding of ChREBP/Mlx heterodimers to the ChoRE

Deterministic Assembly of Arrays of Lithographically Defined WS2 and MoS2 Monolayer Features Directly from Multilayer Sources into Van der Waals Heterostructures

One of the major challenges in the van der Waals (vdW) integration of two-dimensional (2D) materials is achieving high-yield and high-throughput assembly of predefined sequences of monolayers into heterostructure arrays. Mechanical exfoliation has recently been studied as a promising technique to transfer monolayers from a multilayer source synthesized by other techniques, allowing the deposition of a wide variety of 2D materials without exposing the target substrate to harsh synthesis conditions. Although a variety of processes have been developed to exfoliate the 2D materials mechanically from the source and place them deterministically onto a target substrate, they can typically transfer only either a wafer-scale blanket or one small flake at a time with uncontrolled size and shape. Here, we present a method to assemble arrays of lithographically defined monolayer WS2 and MoS2 features from multilayer sources and directly transfer them in a deterministic manner onto target substrates. This exfoliate-align-release process - without the need of an intermediate carrier substrate - is enabled by combining a patterned, gold-mediated exfoliation technique with a new optically transparent, heat-releasable adhesive. WS2/MoS2 vdW heterostructure arrays produced by this method show the expected interlayer exciton between the monolayers. Light-emitting devices using WS2 monolayers were also demonstrated, proving the functionality of the fabricated materials. Our work demonstrates a significant step toward developing mechanical exfoliation as a scalable dry transfer technique for the manufacturing of functional, atomically thin materials

'Sly grog' and 'homebrew': a qualitative examination of illicit alcohol and some of its impacts on Indigenous communities with alcohol restrictions in regional and remote Queensland (Australia)

Background: Indigenous communities in Queensland (Australia) have been subject to Alcohol Management Plans since 2002/03, with significant penalties for breaching restrictions. 'Sly grog' and 'homebrew' provide access to alcohol despite restrictions. This paper describes how this alcohol is made available and the risks and impacts involved. In affected towns and communities across a large area of rural and remote Queensland, interviews and focus groups documented experiences and views of 255 long-standing community members and service providers. Using an inductive framework, transcribed interviews were analysed to identify supply mechanisms, community and service provider responses and impacts experienced. Results: 'Homebrew' was reportedly manufactured in just a few localities, in locally-specific forms bringing locally-specific harms. However, 'sly grog' sourced from licensed premises located long distances from communities, is a widespread concern across the region. 'Sly grog' sellers circumvent retailers' takeaway liquor license conditions, stockpile alcohol outside restricted areas, send hoax messages to divert enforcement and take extraordinary risks to avoid apprehension. Police face significant challenges to enforce restrictions. On-selling of 'sly grog' appears more common in remote communities with total prohibition. Despite different motives for involvement in an illicit trade 'sly grog' consumers and sellers receive similar penalties. Conclusions: There is a need for: (a) a more sophisticated regional approach to managing takeaway alcohol sales from licensed suppliers, (b) targeted penalties for 'sly grog' sellers that reflect its significant community impact, (c) strategies to reduce the demand for alcohol and (d) research to assess the effects of these strategies in reducing harms.Michelle S. Fitts, Jan Robertson, Simon Towle, Chris M. Doran, Robyn McDermott, Adrian Miller, Stephen Margolis, Valmae Ypinazar and Alan R. Cloug

Making sense of illness: the experiences of users of complementary medicine

The present study investigated the experiences of users of complementary and alternative medicine (CAM) using a qualitative approach. In-depth interviews were conducted with 11 frequent users and analysed using interpretative phenomenological analysis (IPA). Results indicated that the patient-practitioner relationship and explanatory frameworks provided by CAM were perceived as important components of the therapeutic process, irrespective of treatment efficacy. CAM served a variety of functions beyond the explicit relief of symptoms by increasing energy and relaxation, facilitating coping and enhancing self/other awareness. It is therefore important that these wider effects are taken into account when evaluating complementary medicine in order to accurately reflect patients' experiences

Relationship between Tibial conformation, cage size and advancement achieved in TTA procedure

Previous studies have suggested that there is a theoretical discrepancy between the cage size and the resultant tibial tuberosity advancement, with the cage size consistently providing less tibial tuberosity advancement than predicted. The purpose of this study was to test and quantify this in clinical cases. The hypothesis was that the advancement of the tibial tuberosity as measured by the widening of the proximal tibia at the tibial tuberosity level after a standard TTA, will be less than the cage sized used, with no particular cage size providing a relative smaller or higher under-advancement, and that the conformation of the proximal tibia will have an influence on the amount of advancement achieved

Mouse Pancreatic Endocrine Cell Transcriptome Defined in the Embryonic Ngn3-Null Mouse

OBJECTIVE—To document the transcriptome of the pancreatic islet during the early and late development of the mouse pancreas and highlight the qualitative and quantitative features of gene expression that contribute to the specification, growth, and differentiation of the major endocrine cell types. A further objective was to identify endocrine cell biomarkers, targets of diabetic autoimmunity, and regulatory pathways underlying islet responses to physiological and pathological stimuli

Activity of the DNA minor groove cross-linking agent SG2000 (SJG-136) against canine tumours

BACKGROUND: Cancer is the leading cause of death in older dogs and its prevalence is increasing. There is clearly a need to develop more effective anti-cancer drugs in dogs. SG2000 (SJG-136) is a sequence selective DNA minor groove cross-linking agent. Based on its in vitro potency, the spectrum of in vivo and clinical activity against human tumours, and its tolerability in human patients, SG2000 has potential as a novel therapeutic against spontaneously occurring canine malignancies. RESULTS: In vitro cytotoxicity was assessed using SRB and MTT assays, and in vivo activity was assessed using canine tumour xenografts. DNA interstrand cross-linking (ICL) was determined using a modification of the single cell gel electrophoresis (comet) assay. Effects on cell cycle distribution were assessed by flow cytometry and measurement of γ-H2AX by immunofluorescence and immunohistochemistry. SG2000 had a multi-log differential cytotoxic profile against a panel of 12 canine tumour cell lines representing a range of common tumour types in dogs. In the CMeC-1 melanoma cell line, DNA ICLs increased linearly with dose following a 1 h treatment. Peak ICL was achieved within 1 h and no removal was observed over 48 h. A relationship between DNA ICL formation and cytotoxicity was observed across cell lines. The formation of γ-H2AX foci was slow, becoming evident after 4 h and reaching a peak at 24 h. SG2000 exhibited significant anti-tumour activity against two canine melanoma tumour models in vivo. Anti-tumour activity was observed at 0.15 and 0.3 mg/kg given i.v. either once, or weekly x 3. Dose-dependent DNA ICL was observed in tumours (and to a lower level in peripheral blood mononuclear cells) at 2 h and persisted at 24 h. ICL increased following the second and third doses in a repeated dose schedule. At 24 h, dose dependent γ-H2AX foci were more numerous than at 2 h, and greater in tumours than in peripheral blood mononuclear cells. SG2000-induced H2AX phosphorylation measured by immunohistochemistry showed good correspondence, but less sensitivity, than measurement of foci. CONCLUSIONS: SG2000 displayed potent activity in vitro against canine cancer cell lines as a result of the formation and persistence of DNA ICLs. SG2000 also had significant in vivo antitumour activity against canine melanoma xenografts, and the comet and γ-H2AX foci methods were relevant pharmacodynamic assays. The clinical testing of SG2000 against spontaneous canine cancer is warranted. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12917-015-0534-2) contains supplementary material, which is available to authorized users

Evaluation of Important Treatment Parameters in Supraphysiological Thermal Therapy of Human Liver Cancer HepG2 Cells

This study was aimed at simulating the effect of various treatment parameters like heating rate (HR), peak temperature (PT) and hold/total treatment time on the viability of human liver cancer HepG2 cells subjected to different thermal therapy conditions. The problem was approached by investigating the injury kinetics obtained using experimentally measured viability of the cells, heated to temperatures of 50–70°C for 0–9 min at HRs of 100, 200, 300 and 525°C min(−1). An empirical expression obtained between the activation energy (E) and HR was extended to obtain the E values over a broad range of HRs from 5 to 600°C min(−1) that mimic the actual conditions encountered in a typical thermal therapy protocol. Further, the effect of the HR (5–600°C min(−1)) and PT (50–85°C) on the cell survival was studied over a range of hold times. A significant drop in survival from 90% to 0% with the simultaneous increase in HR and PT was observed as the hold time increased from 0 to 5 min. For complete cell death, the hold time increased with the increase in the HR for a given PT, while the total time showed presence of minima for 60, 65 and 70°C at HRs of 50, 100 and 200°C min(−1), respectively

Building blocks for social accountability: a conceptual framework to guide medical schools

Background: This paper presents a conceptual framework developed from empirical evidence, to guide medical schools aspiring towards greater social accountability. Methods: Using a multiple case study approach, seventy-five staff, students, health sector representatives and community members, associated with four medical schools, participated in semi-structured interviews. Two schools were in Australia and two were in the Philippines. These schools were selected because they were aspiring to be socially accountable. Data was collected through on-site visits, field notes and a documentary review. Abductive analysis involved both deductive and inductive iterative theming of the data both within and across cases. Results: The conceptual framework for socially accountable medical education was built from analyzing the internal and external factors influencing the selected medical schools. These factors became the building blocks that might be necessary to assist movement to social accountability. The strongest factor was the demands of the local workforce situation leading to innovative educational programs established with or without government support. The values and professional experiences of leaders, staff and health sector representatives, influenced whether the organizational culture of a school was conducive to social accountability. The wider institutional environment and policies of their universities affected this culture and the resourcing of programs. Membership of a coalition of socially accountable medical schools created a community of learning and legitimized local practice. Communities may not have recognized their own importance but they were fundamental for socially accountable practices. The bedrock of social accountability, that is, the foundation for all building blocks, is shared values and aspirations congruent with social accountability. These values and aspirations are both a philosophical understanding for innovation and a practical application at the health systems and education levels. Conclusions: While many of these building blocks are similar to those conceptualized in social accountability theory, this conceptual framework is informed by what happens in practice - empirical evidence rather than prescriptions. Consequently it is valuable in that it puts some theoretical thinking around everyday practice in specific contexts; addressing a gap in the medical education literature. The building blocks framework includes guidelines for social accountable practice that can be applied at policy, school and individual levels