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VO2 films prepared on amorphous substrates are generally nanocrystalline and have low semiconductor–metal transition (SMT) properties. The current research reported that both the undoped and Nb‐doped VO2 films, composed of differently‐orientated single‐crystalline domains, can be prepared on amorphous quartz substrates through facile annealing of sputtered precursors, with their structures, electric properties, optical properties, and thermochromism being systematically studied. The results showed that the resistance change of the undoped VO2 films across the SMT was ∼3000 times. The SMT critical temperature (Tc) of the sc‐domain VO2 films can be decreased to room temperature by the Nb doping, and the resistance change across the SMT could remain approximately two orders of magnitude higher when the Tc was decreased to 27°C. It was seen that both the semiconductor‐phase undoped and Nb‐doped VO2 films featured defect‐activated conductances, with the Nb donor ionization energy being 0.14–0.17 eV. The absorption coefficients of the VO2 films were obtained by fitting the transmittance and reflectance optical spectra with the Drude‐Lorentz dispersion model, and the Nb doping widened and merged the d|| and π* bands, with both the optical and physical gaps being decreased due to the band widening. The thermochromic performances were also studied, and the result showed that the solar light modulation could remain 90% of the undoped film when the Tc was decreased to 27°C by the Nb doping, so the Nb‐doped VO2 films can be a good candidate for preparing thermochromic energy‐saving coatings. [ABSTRACT FROM AUTHOR]

Background: Respiratory tract infections are readily transmitted in care homes. Airborne transmission of pathogens causing respiratory tract illness is largely unmitigated. Portable high-efficiency-particulate-air (HEPA) filtration units capture microbial particles from the air, but it is unclear whether this is sufficient to reduce infections in care home residents. The Air Filtration to prevent symptomatic winter Respiratory Infections (including COVID-19) in care homes (AFRI-c) randomized controlled trial will determine whether using HEPA filtration units reduces respiratory infection episodes in care home residents. Methods: AFRI-c is a cluster randomized controlled trial that will be delivered in residential care homes for older people in England. Ninety-one care homes will be randomised to take part for one winter period. The intervention care homes will receive HEPA filtration units for use in communal areas and private bedrooms. Normal infection control measures will continue in all care homes. Anonymised daily data on symptoms will be collected for up to 30 residents. Ten to 12 of these residents will be invited to consent to a primary care medical notes review and (in intervention homes) to having an air filter switched on in their private room. The primary outcome will be number of symptomatic winter respiratory infection episodes. Secondary outcomes include specific clinical measures of infection, number of falls / near falls, number of laboratory confirmed infections, hospitalisations, staff sickness and cost-effectiveness. A mixed methods process evaluation will assess intervention acceptability and implementation. Discussion: The results of AFRI-c will provide vital information about whether portable HEPA filtration units reduce symptomatic winter respiratory infections in older care home residents. Findings about effectiveness, fidelity, acceptability and cost-effectiveness will support stakeholders to determine the use of HEPA filtration units as part of infection control policies. [ABSTRACT FROM AUTHOR]

Over the past decades, red meat allergy, also known as mammalian meat allergy, which manifests differently from classic food allergies, has been reported in different countries and regions, including China. The allergen of this disease is not a protein but an oligosaccharide: galactose‐α‐1,3‐galactose, i.e., alpha‐gal or α‐gal. Therefore, this clinical syndrome is also called α‐gal syndrome (AGS). It clinically manifests as delayed anaphylaxis, i.e., patients generally develop allergic symptoms 2–6 h after ingesting red meat. This clinical manifestation is believed to be related to sensitization to α‐gal after tick bites. Sensitized individuals may also develop anaphylaxis after ingesting food and medicine or being exposed to medical equipment containing α‐gal, such as cetuximab and gelatin. Here, the literature on AGS is reviewed for a better understanding of its pathogenesis, clinical diagnosis, and treatment. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) is a potential wide band gap semiconductor, but its high photoelectron-hole pairs recombination rate and poor light absorption ability limit its application to photoelectrochemical (PEC) water oxidation. To solve these problems, in this work, a reasonable band structure engineering was carried out on ZnO nanorod arrays (ZnO NRAs) with the co-decoration of nitrogen doped g-C3N4 (NCN) and carbon quantum dot (CQDs) solution. Narrow band gap NCN was loaded onto the surface of ZnO NRAs by a simple spin coating method, and then CQDs were modified on the ZnO/NCN NRAs. The composite photoanode of ZnO/NCN/CQDs NRAs was finally obtained. The PEC performance of the composite photoanode reaches 1.82 times that of the pristine ZnO photoanode, with a photocurrent density of up to 1.20 mA cm−2 at 1.23 V (vs. RHE) bias. The calculated value of ABPE for the composite photoanode was 0.258%, compared with 0.123% for the bare ZnO NRAs. The co-decoration of NCN and CQDs enhanced the charge separation efficiency and expanded the spectral response range, contributing to the improved PEC properties of the composite photoanode. [ABSTRACT FROM AUTHOR]

Electron transfer and its kinetics play a major role in the photocatalysis of metal/semiconductor systems. Using in situ photoconductances, in situ photoabsorption, and photoinduced spectroscopic techniques, the present research aimed to gain a deep insight into electron transfer pathways and their kinetics for Ag/TiO2 systems under sub-bandgap light illumination and gaseous conditions. The results revealed that electrons generated in TiO2 can transfer to Ag nanoparticles at fast rates, and plasmon-generated electrons in Ag nanoparticles can also transfer to TiO2. However, it was found that plasmon-assisted hot electron transfer efficiency is much lower than the electron transition from the valence band to the conduction band of TiO2. Rather than plasmonic active spots, the results showed that Ag nanoparticles acted as co-catalyst sites bridging electron transfer to recombination in a methanol-containing N2 atmosphere. As a result, photocatalytic isopropanol dehydrogenation was decreased. Independent of Ag decorations, it was also indicated that isopropanol dehydrogenation mainly occurred over TiO2 surfaces; therefore, Ag nanoparticles did not increase photocatalytic activities. Our results may provide a different viewpoint on sub-bandgap light-induced Ag/TiO2 photocatalysis under gaseous conditions; this may also facilitate the understanding of the photocatalytic mechanism of metal/semiconductor systems. [ABSTRACT FROM AUTHOR]

Nanofluidic channels with tailored ion transport dynamics are usually used as channels for ion transport, to enable high-performance ion regulation behaviors. The rational construction of nanofluidics and the introduction of external fields are of vital significance to the advancement and development of these ion transport properties. Focusing on the recent advances of nanofluidics, in this review, various dimensional nanomaterials and their derived homogeneous/heterogeneous nanofluidics are first briefly introduced. Then we discuss the basic principles and properties of ion transport in nanofluidics. As the major part of this review, we focus on recent progress in ion transport in nanofluidics regulated by external physical fields (electric field, light, heat, pressure, etc.) and chemical fields (pH, concentration gradient, chemical reaction, etc.), and reveal the advantages and ion regulation mechanisms of each type. Moreover, the representative applications of these nanofluidic channels in sensing, ionic devices, energy conversion, and other areas are summarized. Finally, the major challenges that need to be addressed in this research field and the future perspective of nanofluidics development and practical applications are briefly illustrated. [ABSTRACT FROM AUTHOR]