Mixed-Metal Tungsten Oxide Photoanode Materials Made by Pulsed-Laser in Liquids Synthesis.

Globally scalable sunlight-driven devices that convert solar energy into storable fuels will require efficient light absorbers that are made of non-precious elements. Suitable photoanode materials are yet to be discovered. Here we utilised the timesaving nature of pulsed-laser-in-liquids synthesis and prepared a series of neat and mixed-metal tungsten oxide photoanode materials to investigate the effect of ad-metals on optical and photocurrent generation properties. We obtained sub-µm-sized materials with different colours from W, Al, Ta, or first-row transition metal targets in water or aqueous ammonium metatungstate solutions. We observed metastable polymorphs of WO3 and tungsten oxides with varying degrees of oxygen deficiency. Pulsed-laser in liquids synthesis of Ni in ammonium metatungstate solutions produce hollow spheres (with ≤6 % Ni with respect to W). Photocurrent generation in strong aqueous acid is highest in mixed-metal tungsten oxide photoanode materials with around 5 % of iron or nickel.

Plasmon assisted 3D microstructuring of gold nanoparticle-doped polymers.

3D laser lithography of a negative photopolymer (zirconium/silicon hybrid solgel SZ2080) doped with gold nanoparticles (Au NPs) is performed with a 515 nm and 300 fs laser system and the effect of doping is explored. By varying the laser-generated Au NP doping concentration from 4.8 · 10(-6) wt% to 9.8 · 10(-3) wt% we find that the fabricated line widths are enlarged by up to 14.8% compared to structures achieved in pure SZ2080. While implicating a positive effect on the photosensitivity, the doping has no adverse impact on the mechanical quality of intricate 3D microstructures produced from the doped nanocompound. Additionally, we found that SZ2080 increases the long term (∼months) colloidal stability of Au NPs in isopropanol. By discussing the nanoparticle-light interaction in the 3D polymer structures we provide implications that our findings might have on other fields, such as biomedicine and photonics.

Inclusion of supported gold nanoparticles into their semiconductor support.

Supported particles are easily accessible as standard materials used in heterogeneous catalysis and photocatalysis. This article addresses our exemplary studies on the integration of supported nanoparticles into their solid support, namely gold nanoparticles into zinc oxide sub-micrometer spheres, by energy controlled pulsed laser melting in a free liquid jet. This one-step, continuous flow-through processing route reverses the educt's structure, converting the ligand-free surface adsorbate into a spherical subsurface solid inclusion within its former support. The results show how a nanoparticulate surface adsorbate can be included in the form of crystalline nanoparticles into the resolidified support matrix, demonstrated by using plasmonic nanoparticles and semiconductor microparticles as reference materials.

MethOxyfluraNe in InTerventiOnal Radiology (MONITOR): A randomised controlled trial.

INTRODUCTION: Procedural sedation and pain management in interventional radiology (IR) are of critical importance to successful outcomes but remain under-researched. Methoxyflurane has been previously used in some minor procedures with several advantages including rapid onset and offset and a good safety profile. The purpose of this study was to evaluate methoxyflurane for procedures in IR. METHODS: A randomised, double-blind, placebo-controlled trial was performed between October 2021 and November 2022. Patients presenting for portacath insertion, portacath removal or solid organ biopsy were randomised to either methoxyflurane or placebo. Three hundred and fourteen patients were enrolled in total. Patients were supplied with one Penthrox inhaler containing either 3 mL methoxyflurane or placebo. The primary endpoints of the study were change in pain and anxiety scores compared with baseline, measured on a standardised visual analogue scale (VAS) pre-procedure, at 5-min intervals during the procedure and post-procedure. Baselines scores were controlled for in the statistical analysis. Safety analysis was also performed. RESULTS: One hundred and sixty-nine patients received methoxyflurane and 145 received placebo. Baseline characteristics were similar between the two groups. The methoxyflurane group had lower pain and anxiety scores throughout the procedure (P < 0.001) with 2.5 times less pain (VAS 1.08/10) and 1.6 times less anxiety (VAS 0.97/10) on average. Lower post-procedure pain (mean 0.72 vs 1.44; P < 0.001) and anxiety (mean 0.55 vs 1.13; P = 0.008) were also observed with methoxyflurane. There were no drug or major procedure-related adverse events. CONCLUSION: The results of this study suggest that methoxyflurane provides safe and effective analgesia and anxiolysis for some procedures in IR.

Falls risk factor assessment and secondary prevention in the older old.

AIMS: Falls are common in 80-plus year-olds and there is evidence available in terms of risk factors and prevention measures. We aimed to review falls risk factor assessment and secondary prevention strategies in patients in this age group presenting acutely to services other than older adult health services at Waitemata District Health Board. METHODS: We retrospectively reviewed electronic hospital records of those >80 years presenting to acute services with a primary or secondary diagnosis of a fall, or fall-related injury. Admission characteristics, risk factor identification and subsequent referrals for falls prevention were recorded. Six-month outcomes including readmissions and mortality were assessed. RESULTS: One hundred and thirty-eight discharge summaries were reviewed (71% female, median age 89). Thirty-one percent had a previous fall-related hospital admission in the six months prior. There was high prevalence of psychoactive medications (51%) and falls-related cardiovascular drugs (78%) at discharge. No patients were referred for falls prevention programmes or geriatric assessment at discharge. At six months 19% had died and 44% had been readmitted. CONCLUSIONS: There are inadequate falls prevention referrals, indicating a quality of care gap. The older age group presenting to acute services have high rates of polypharmacy, hospitalisations and death.

Germanium Sub-Microspheres Synthesized by Picosecond Pulsed Laser Melting in Liquids: Educt Size Effects.

Pulsed laser melting in liquid (PLML) has emerged as a facile approach to synthesize submicron spheres (SMSs) for various applications. Typically lasers with long pulse durations in the nanosecond regime are used. However, recent findings show that during melting the energy absorbed by the particle will be dissipated promptly after laser-matter interaction following the temperature decrease within tens of nanoseconds and hence limiting the efficiency of longer pulse widths. Here, the feasibility to utilize a picosecond laser to synthesize Ge SMSs (200~1000 nm in diameter) is demonstrated by irradiating polydisperse Ge powders in water and isopropanol. Through analyzing the educt size dependent SMSs formation mechanism, we find that Ge powders (200~1000 nm) are directly transformed into SMSs during PLML via reshaping, while comparatively larger powders (1000~2000 nm) are split into daughter SMSs via liquid droplet bisection. Furthermore, the contribution of powders larger than 2000 nm and smaller than 200 nm to form SMSs is discussed. This work shows that compared to nanosecond lasers, picosecond lasers are also suitable to produce SMSs if the pulse duration is longer than the material electron-phonon coupling period to allow thermal relaxation.

Continuous Monitoring via Tethered Electroencephalography of Spontaneous Recurrent Seizures in Mice.

We describe here a simple, cost-effective apparatus for continuous tethered electroencephalographic (EEG) monitoring of spontaneous recurrent seizures in mice. We used a small, low torque slip ring as an EEG commutator, mounted the slip ring onto a standard mouse cage and connected rotary wires of the slip ring directly to animal's implanted headset. Modifications were made in the cage to allow for a convenient installation of the slip ring and accommodation of animal ambient activity. We tested the apparatus for hippocampal EEG recordings in adult C57 black mice. Spontaneous recurrent seizures were induced using extended hippocampal kindling (≥95 daily stimulation). Control animals underwent similar hippocampal electrode implantations but no stimulations were given. Combined EEG and webcam monitoring were performed for 24 h daily for 5-9 consecutive days. During the monitoring periods, the animals moved and accessed water and food freely and showed no apparent restriction in ambient cage activities. Ictal-like hippocampal EEG discharges and concurrent convulsive behaviors that are characteristics of spontaneous recurrent seizures were reliably recorded in a majority of the monitoring experiments in extendedly kindled but not in control animals. However, 1-2 rotary wires were disconnected from the implanted headset in some animals after continuous recordings for ≥5 days. The key features and main limitations of our recording apparatus are discussed.

Gradual modification of ITO particle's crystal structure and optical properties by pulsed UV laser irradiation in a free liquid jet.

Indium tin oxide (ITO) particle coatings are known for high transparency in the visible, good conductive properties and near-infrared absorption. These properties depend on ITO particle's stoichiometric composition, defects and size. Here we present a method to gradually change ITO particle's optical properties by a simple and controlled laser irradiation process. The defined irradiation process and controlled energy dose input allows one to engineer the absorption and transmission of coatings made from these particles. We investigate the role of the surrounding solvent, influence of laser fluence and the specific energy dose targeting modification of the ITO particle's morphology and chemistry by stepwise laser irradiation in a free liquid jet. TEM, SEM, EDX, XPS, XRD and Raman are used to elucidate the structural, morphological and chemical changes of the laser-induced ITO particles. On the basis of these results the observed modification of the optical properties is tentatively attributed to chemical changes, e.g. laser-induced defects or partial reduction.

Effects of neonatal hypoxic-ischemic episodes on late seizure outcomes in C57 black mice.

We examined brain injury and seizures in adult C57 black mice (C57/BL6) that underwent neonatal hypoxic-ischemic (HI) episodes. Mouse pups of 7 days-old underwent a ligation of the right common carotid artery and a subsequent hypoxic challenge (8% O2 for 45min). Post-HI mice were implanted with intracranial electrodes at 2-3 months of age, subjected to behavioral/EEG recordings and hippocampal electrical stimulation in next several months and then euthanized for brain histological assessments at ages of 11-12 months. Histological assessment revealed ipsilateral brain infarctions in 9 post-HI animals. Evident motor seizures were found to occur in only 2 animals with histologically identified cystic infarctions but not in the 21 post-HI animals with or without infarctions. In response to the hippocampal stimulation, post-HI animals were less prone than sham controls to evoked motor seizures. We thus suggest that adult C57 black mice may have low propensity of developing epileptic seizures following the neonatal HI episode. Our present observations may be relevant to future investigation of post-HI epileptogenesis in mouse models.

Factors influencing total carbon dioxide concentrations in plasma of thoroughbred and standardbred racehorses.

Horse racing authorities impose a limit on the concentration of plasma 'total carbon dioxide' (TCO2), typically 36 mM with action taken above 37 mM, as measured by an electrochemical gas analyzer. It is of interest to understand the distribution of TCO2 in a 'normal' population of racehorses and determine probabilities of members of this population exceeding these current regulatory and action limits. TCO2 levels in equine plasma samples have been modelled for 12 months (2011-2012) of thoroughbred (3076 measurements) and standardbred (3788 measurements) data in Australia. The two populations have a common seasonal pattern, while the non-seasonal distributions differ. A single Gaussian distribution about the seasonal pattern explains the thoroughbred data, but there is evidence for a second Gaussian component for the standardbred horses. A Gaussian mixture model for standardbred horses gave a main component that matched the thoroughbred distribution, which was centred about 30.2 mM, and a smaller (about 20 % of the total density) Gaussian centred at 32.3 mM. The existence of a second, higher-meaned population of standardbred horses points to increased use of alkalinizing salts among a minority of trainers, whom still, however, maintain mostly legal levels of TCO2. Identification of this group can be used to direct intelligence-based testing with a view to limiting use of these products. Probabilities of exceeding limits are affected by seasonality, but the current rules remain conservative.