Self‐Assembled BiFeO3‐ε‐Fe2O3 Vertical Heteroepitaxy for Visible Light Photoelectrochemistry

Self‐assembled vertical heterostructure with a high interface‐to‐volume ratio offers tremendous opportunities to realize intriguing properties and advanced modulation of functionalities. Here, a heterostructure composed of two visible‐light photocatalysts, BiFeO₃ (BFO) and ε‐Fe₂O₃ (ε‐FO), is designed to investigate its photoelectrochemical performance. The structural characterization of the BFO‐FO heterostructures confirms the phase separation with BFO nanopillars embedded in the ε‐FO matrix. The investigation of band structure of the heterojunction suggests the assistance of photoexcited carrier separation, leading to an enhanced photoelectrochemical performance. The insights into the charge separation are further revealed by means of ultrafast dynamics and electrochemical impedance spectroscopies. This work shows a delicate design of the self‐assembled vertical heteroepitaxy by taking advantage of the intimate contact between two phases that can lead to a tunable charge interaction, providing a new configuration for the optimization of photoelectrochemical cell.     

Evaluation of dental enamel caries assessment using Quantitative Light Induced Fluorescence and Optical Coherence Tomography

An in vitro study of morphological alterations between sound dental structure and artificially induced white spot lesions in human teeth, was performed through the loss of fluorescence by Quantitative Light‐Induced Fluorescence (QLF) and the alterations of the light attenuation coefficient by Optical Coherence Tomography (OCT). To analyze the OCT images using a commercially available system, a special algorithm was applied, whereas the QLF images were analyzed using the software available in the commercial system employed. When analyzing the sound region against white spot lesions region by QLF, a reduction in the fluorescence intensity was observed, whilst an increase of light attenuation by the OCT system occurred. Comparison of the percentage of alteration between optical properties of sound and artificial enamel caries regions showed that OCT processed images through the attenuation of light enhanced the tooth optical alterations more than fluorescence detected by QLF System.

QLF versus OCT imaging of enamel caries: a photonics assessment     

Willingness to Act upon Beliefs about ‘Treatment as Prevention’ among Australian Gay and Bisexual Men

HIV ‘treatment as prevention’ (TasP) is highly effective in reducing HIV transmission in serodiscordant couples. There has been little examination of gay and bisexual men’s attitudes towards TasP, particularly regarding men’s willingness to act on beliefs about TasP. We conducted an online cross-sectional survey of Australian men in late 2012 to investigate knowledge and beliefs about new developments in HIV prevention. Amongst 839 men (mean age 39.5 years), men tended to disagree that TasP was sufficiently effective to justify reduced condom use, although HIV-positive men had more favourable attitudes. Only a minority of men were aware of any evidence for TasP; and one-quarter incorrectly believed that evidence for the effectiveness of TasP already existed for the homosexual population. One-fifth (20.5%) of men reported that they would be willing to have condomless anal intercourse with an opposite-status sexual partner when the HIV-positive partner was taking HIV treatments. Factors independently associated with such willingness were: HIV-positive serostatus, reporting any serodiscordant or serononconcordant condomless anal intercourse with a regular male partner in the previous six months, reporting any condomless anal intercourse with a casual male partner in the previous six months, and having greater beliefs in the effectiveness of TasP. This indicated that the men most willing to rely on TasP to prevent transmission were already engaging in higher risk practices. Biomedical HIV prevention represents a rapidly changing environment with new research as well as community and policy responses emerging at a fast pace. For men with serodiscordant sexual partners to successfully apply TasP to reducing transmission risk, more support and education is needed to enable better utilisation of TasP in specific relational and sexual contexts.     

Computational investigation on MB<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript> (M = Li-Cs,Be-Ba,Sc-La and Ti; <Emphasis Type="Italic">n</Emphasis> = 28 and 38)

Differing from the weakly antiaromatic B₈₀ buckyball, the medium-sized C ₁–B₂₈ and D _2h –B₃₈, as well as their mono- to tetra-anions, are highly aromatic, as indicated by the negative nucleus-independent chemical shifts (NICSs) at their cage centers. The interior cavities and high aromaticity of the B₂₈ and B₃₈ cages render them very promising hosts to accommodate diverse metal atoms. Accordingly, we carried out systematic density functional theory (DFT) computations on the structures, stabilities and electronic properties of metalloborofullerenes MB _n (M?=?Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Sc, Y, La and Ti; n?=?28 and 38). Among them, besides the recently reported M@B₃₈(M?=?Sc, Y and Ti) [Lu et al. (2015) Phys Chem Chem Phys 17:20897–20902], Ti@B₂₈ and M@B₃₈ (M?=?Ca and La) also favor endohedral structures with large binding energies, and are suggested promising targets for experimental applications. Note that Ti@B₂₈ is the first endohedral derivative based on the new B₂₈ fullerene, and La@B₃₈ features the largest metal size inside a B₃₈ cage thus far. These endohedral derivatives, as exemplified by Ca@B₃₈, may exhibit σ and π double aromaticity over the whole cage surface, indicating their considerable stability. In contrast, the other metals prefer to reside at the exterior cage surface, due mainly to the mismatch of their sizes with the boron cages, though the size match is not the only factor to determine their doping form. Furthermore, the infrared absorption spectra and ¹¹B nuclear magnetic resonance spectra of the three new M@B _n complexes were computed to assist future experimental characterization.

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Graphical Abstract Putting more metals into medium-sized boron cages!

     

Impact of Aldosterone Antagonists on Sudden Cardiac Death Prevention in Heart Failure and Post-Myocardial Infarction Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background and Objectives

Sudden cardiac death (SCD) is a severe burden of modern medicine. Aldosterone antagonist is publicized as effective in reducing mortality in patients with heart failure (HF) or post myocardial infarction (MI). Our study aimed to assess the efficacy of AAs on mortality including SCD, hospitalization admission and several common adverse effects.

Methods

We searched Embase, PubMed, Web of Science, Cochrane library and clinicaltrial.gov for randomized controlled trials (RCTs) assigning AAs in patients with HF or post MI through May 2015. The comparator included standard medication or placebo, or both. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Event rates were compared using a random effects model. Prospective RCTs of AAs with durations of at least 8 weeks were selected if they included at least one of the following outcomes: SCD, all-cause/cardiovascular mortality, all-cause/cardiovascular hospitalization and common side effects (hyperkalemia, renal function degradation and gynecomastia).

Results

Data from 19,333 patients enrolled in 25 trials were included. In patients with HF, this treatment significantly reduced the risk of SCD by 19% (RR 0.81; 95% CI, 0.67–0.98; p = 0.03); all-cause mortality by 19% (RR 0.81; 95% CI, 0.74–0.88, p<0.00001) and cardiovascular death by 21% (RR 0.79; 95% CI, 0.70–0.89, p<0.00001). In patients with post-MI, the matching reduced risks were 20% (RR 0.80; 95% CI, 0.66–0.98; p = 0.03), 15% (RR 0.85; 95% CI, 0.76–0.95, p = 0.003) and 17% (RR 0.83; 95% CI, 0.74–0.94, p = 0.003), respectively. Concerning both subgroups, the relative risks respectively decreased by 19% (RR 0.81; 95% CI, 0.71–0.92; p = 0.002) for SCD, 18% (RR 0.82; 95% CI, 0.77–0.88, p < 0.0001) for all-cause mortality and 20% (RR 0.80; 95% CI, 0.74–0.87, p < 0.0001) for cardiovascular mortality in patients treated with AAs. As well, hospitalizations were significantly reduced, while common adverse effects were significantly increased.

Conclusion

Aldosterone antagonists appear to be effective in reducing SCD and other mortality events, compared with placebo or standard medication in patients with HF and/or after a MI.