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The scientific and societal importance of short-term changes in the thermosphere-ionosphere (T-I) system has highlighted the need to advance our understanding of short-term changes in the lower-middle thermosphere. This need has become increasingly important with the rapid increase in the number of low-earth-orbiting satellites. Geomagnetic activity can dramatically increase thermospheric temperatures and, almost equivalently, thermospheric densities and satellite drag. However, specification of drag during quiet periods may also be problematic when the number of satellites is large. While temperatures and densities at higher altitudes (>~250 km) have been extensively studied and modeled, there is a knowledge gap for densities at lower-middle thermosphere altitudes (< ~200 km). At these lower altitudes the primary sources of thermospheric density data, in situ and drag data from satellites, are rarely available. Remote sensing of temperatures and composition by NASA's Global-scale Observations of the Limb and Disk (GOLD) mission can help fill this gap The GOLD mission produces disk images of neutral temperature, which is key parameter for understanding neutral density in the lower-middle thermosphere. However, since disk images of the temperature have become available only since the launch of GOLD, some researchers may be unfamiliar with the current observational capability that is relevant to the data interpretation. Also, other temperature retrieval techniques than GOLD's have been published. Comparisons indicate that GOLD's technique gives the most consistent results and yields the lowest uncertainties. This paper discusses both temperature retrieval techniques and issues in interpreting GOLD's images of temperatures. [ABSTRACT FROM AUTHOR]

Laboratory classes form an important aspect of bioscience education. However, this environment is challenging for students due to cognitive load and lack of confidence. Familiarising students with aspects of their laboratory classes prior to the session can improve this. This study compares the pre-laboratory scaffolding that bioscience and chemistry students experience across UK HE institutions. Typically, bioscience modules used fewer types of activities than chemistry although reading the protocol was the most common activity for both disciplines. Within bioscience, pre-laboratory activities differed by level: first year undergraduates were more likely to be asked to read the protocol, watch videos or do calculation practice in their modules whereas final year undergraduates were more likely to experience experimental design or contextualised activities. Alongside this, this paper discusses an institutional case study of the development and evaluation of technical laboratory videos as pre-laboratory scaffolding for first year students. These were found to benefit both student focus and enhance confidence: implying that using the videos impacted on cognitive load and hence learning. Exploring barriers to the uptake of these resources identified a lack of awareness of them as a major factor, suggesting that greater integration of such resources would enhance engagement and impact. [ABSTRACT FROM AUTHOR]

In healthy skin, vectorial ion transport gives rise to a transepithelial potential which directly impacts many physiological aspects of skin function. A wound is a physical defect that breaches the epithelial barrier and changes the electrochemical environment of skin. Electroceutical dressings are devices that manipulate the electrochemical environment, host as well as microbial, of a wound. In this review, electroceuticals are organized into three mechanistic classes: ionic, wireless, and battery powered. All three classes of electroceutical dressing show encouraging effects on infection management and wound healing with evidence of favorable impact on keratinocyte migration and disruption of wound biofilm infection. This foundation sets the stage for further mechanistic as well as interventional studies. Successful conduct of such studies will determine the best dosage, timing, and class of stimulus necessary to maximize therapeutic efficacy. [ABSTRACT FROM AUTHOR]

We verify numerically the theoretical stress singularities for two viscoelastic models that occur at sharp corners. The models considered are the Giesekus and Phan-Thien–Tanner (PTT), both of which are shear thinning and are able to capture realistic polymer behaviors. The theoretical asymptotic behavior of these two models at sharp corners has previously been found to involve an integrable solvent and polymer elastic stress singularity, along with narrow elastic stress boundary layers at the walls of the corner. We demonstrate here the validity of these theoretical results through numerical simulation of the classical contraction flow and analyzing the 270 ° corner. Numerical results are presented, verifying both the solvent and polymer stress singularities, as well as the dominant terms in the constitutive equations supporting the elastic boundary layer structures. For comparison at Weissenberg order one, we consider both the Cartesian stress formulation and the alternative natural stress formulation of the viscoelastic constitutive equations. Numerically, it is shown that the natural stress formulation gives increased accuracy and convergence behavior at the stress singularity and, moreover, encounters no upper Weissenberg number limitation in the global flow simulation for sufficiently large solvent viscosity fraction. The numerical simulations with the Cartesian stress formulation cannot reach such high Weissenberg numbers and run into convergence failure associated with the so-called high Weissenberg number problem. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO) is a sensitive tracer of the thermal profile and winds in Mars' middle atmosphere and the chemistry that balances CO2 in the whole atmosphere of Mars. The Emirates Ultraviolet Spectrometer (EMUS) onboard the Emirates Mars Mission Hope probe images Mars at ultraviolet wavelengths from approximately 100 to 170 nm. ΣCO/CO2, the column density ratio of CO to carbon dioxide, provides a sensitive measure of CO relative variability within the Martian thermosphere. Derived from the heritage of ΣO/N2 used at Earth, the ΣCO/CO2 algorithm uses emission from the CO Fourth Positive Group band system to derive the relative column abundance of CO above ∼70 km. We describe the EMUS ΣCO/CO2 algorithm, review the Level 3 data product, and discuss preliminary validation of the algorithm. The ΣCO/CO2 algorithm produces column density ratios that characterize the spatial structure and relative variability of CO abundance in the Martian thermosphere. Plain Language Summary: The Emirates Mars Ultraviolet Spectrometer onboard the Emirates Mars Mission observes light in a wavelength region referred to as far ultraviolet. This study focuses on far ultraviolet light that is produced by carbon monoxide (CO). Observations of far ultraviolet light can be used to determine the relative abundance of CO in the upper atmosphere of Mars. Variations in the relative abundance of CO over time and across different locations can provide valuable information regarding the temperatures and winds in the middle atmosphere of Mars, as well as the chemistry that balances the whole atmosphere of Mars. This study presents a method for converting observations of far ultraviolet light into relative abundances of CO in the upper atmosphere of Mars. Key Points: Emirates Ultraviolet Spectrometer (EMUS) observations provide large scale, high cadence, synoptic views of carbon monoxide (CO) relative column abundance in the lower thermosphere of MarsSignificant variability in CO brightness and relative column abundance is regularly observed in EMUS disk imagesObserved variability of CO relative column abundance in local time, latitude, and solar longitude is inconsistent with model predictions [ABSTRACT FROM AUTHOR]

The health and economic burden of foodborne illness is high, with approximately 2.4 million cases occurring annually in the United Kingdom. A survey to understand the baseline microbial quality and prevalence of food-related hazards of fresh beef mince on retail sale could inform risk assessment, management, and communication to ensure the safety of this commodity. In such a survey, a two-stage sampling design was used to reflect variations in population density and the market share of five categories of retail outlets in Scotland. From January to December 2019, 1,009 fresh minced beef samples were collected from 15 geographic areas. The microbial quality of each sample was assessed using aerobic colony count and Escherichia coli count. Samples were cultured for Campylobacter and Salmonella, and PCR was used to detect target genes (stx1 all variants, stx2 a to g, and rfbO157) for Shiga toxin–producing E. coli (STEC). The presence of viable E. coli O157 and STEC in samples with a positive PCR signal was confirmed via culture and isolation. Phenotypic antimicrobial sensitivity patterns of cultured pathogens and 100 E. coli isolates were determined, mostly via disk diffusion. The median aerobic colony count and E. coli counts were 6.4 3 105 (interquartile range, 6.9 3 104 to 9.6 3 106 ) and ,10 CFU/g (interquartile range, ,10 to 10) of minced beef, respectively. The prevalence was 0.1% (95% confidence interval [CI], 0 to 0.7%) for Campylobacter, 0.3% (95% CI, 0 to 1%) for Salmonella, 22% (95% CI, 20 to 25%) for PCR-positive STEC, and 4% (95% CI, 2 to 5%) for culture-positive STEC. The evidence for phenotypic antimicrobial resistance detected did not give cause for concern, mainly occurring in a few E. coli isolates as single non-susceptibilities to first-line active substances. The low prevalence of pathogens and phenotypic antimicrobial resistance is encouraging, but ongoing consumer food safety education is necessary to mitigate the residual public health risk. [ABSTRACT FROM AUTHOR]

Background: Corticosteroid injections are used in the treatment of hand and wrist conditions. The co-administration of a local anaesthetic and corticosteroid aims to reduce pain after the injection, although no studies have directly compared this with using corticosteroid alone. The aim is to determine whether pain experienced during the 24 h after a corticosteroid injection to the hand and wrist is no worse than (not inferior to) the pain experienced after a corticosteroid and local anaesthetic injection.Methods: A single-site, patient- and assessor-blinded, non-inferiority randomised control trial recording pain visual analogue scale (VAS) scores in patients with a clinical diagnosis of trigger finger, de Quervains tenosynovitis or carpal tunnel syndrome, treated with a 1-ml triamcinolone (40 mg/1 ml) injection co-administered with or without 1 ml of 1% lidocaine. The primary aim is to investigate a difference in pain VAS scores at 1 h after the injection using a mean change score. A 95% power calculation was made using a minimally clinical important difference of 20 mm as the clinically admissible margin of non-inferiority and an assumed standard deviation of 25 mm, from previous studies. Including a 20% fall out rate, 100 patients are required.Discussion: Patients with a clinical diagnosis of trigger finger, de Quervains and carpal tunnel syndrome, are over the age 18 years old and who are able to give written informed consent will be included. Patients will be excluded if they have had previous surgery or corticosteroid injection for the condition being treated at the site considered for injection. Patients will be electronically randomised and injections delivered during their clinic appointment. Pain is assessed using a 100-mm VAS score taken, before and at the time of injection and at 5 min, 1 h, 2 h, 3 h and 24 h after the injection. The secondary outcomes are to determine a difference in pain VAS score at the time of injection and during the 24 h after.Trial Registration: This study is registered on the IRAS (259336) on November 11, 2019, and EudraCT database on October 31, 2019 (2019-003742-32). REC/HRA approval was given in January 2020, and Clinical Trial Authorisation from the MHRA was given in December 2019. The study is registered on ClinicalTrials.gov ( NCT04253457 ) on February 5, 2020. [ABSTRACT FROM AUTHOR]

Piezoresponse Force Microscopy (PFM) is a popular tool for the study of ferroelectric and piezoelectric materials at the nanometer level. Progress in the development of piezoelectric MEMS fabrication is highlighting the need to characterize absolute displacement at the nanometer and Å ngstrom scales, something Atomic Force Microscopy (AFM) might do but PFM cannot. Absolute displacement is measured by executing a polarization measurement of the ferroelectric or piezoelectric capacitor in question while monitoring the absolute vertical position of the sample surface with a stationary AFM cantilever. Two issues dominate the execution and precision of such a measurement: (1) the small amplitude of the electrical signal from the AFM at the Å ngstrom level and (2) calibration of the AFM. The authors have developed a calibration routine and test technique for mitigating the two issues, making it possible to use an atomic force microscope to measure both the movement of a capacitor surface as well as the motion of a micro-machine structure actuated by that capacitor. The theory, procedures, pitfalls, and results of using an AFM for absolute piezoelectric measurement are provided. [ABSTRACT FROM AUTHOR]

In the tolerogenic liver, inadequate or ineffective interferon signaling fails to clear chronic HBV infection. Lambda IFNs (IFNL) bind the interferon lambda receptor-1 (IFNLR1) which dimerizes with IL10RB to induce transcription of antiviral interferon-stimulated genes (ISG). IFNLR1 is expressed on hepatocytes, but low expression may limit the strength and antiviral efficacy of IFNL signaling. Three IFNLR1 transcriptional variants are detected in hepatocytes whose role in regulation of IFNL signaling is unclear: a full-length and signaling-capable form (isoform 1), a form that lacks a portion of the intracellular JAK1 binding domain (isoform 2), and a secreted form (isoform 3), the latter two predicted to be signaling defective. We hypothesized that altering expression of IFNLR1 isoforms would differentially impact the hepatocellular response to IFNLs and HBV replication. Induced pluripotent stem-cell derived hepatocytes (iHeps) engineered to contain FLAG-tagged, doxycycline-inducible IFNLR1 isoform constructs were HBV-infected then treated with IFNL3 followed by assessment of gene expression, HBV replication, and cellular viability. Minimal overexpression of IFNLR1 isoform 1 markedly augmented ISG expression, induced de novo proinflammatory gene expression, and enhanced inhibition of HBV replication after IFNL treatment without adversely affecting cell viability. In contrast, overexpression of IFNLR1 isoform 2 or 3 partially augmented IFNL-induced ISG expression but did not support proinflammatory gene expression and minimally impacted HBV replication. IFNLR1 isoforms differentially influence IFNL-induced gene expression and HBV replication in hepatocytes. Regulated IFNLR1 expression in vivo could limit the capacity of this pathway to counteract HBV replication. [Display omitted] • IFNLR1 isoforms differentially support expression of lambda interferon-induced genes in hepatocytes. • IFNLR1 isoform 1 supports antiviral and inflammatory gene expression and maximal inhibition of HBV replication. • IFNLR1 isoforms 2 and 3 support antiviral, but not inflammatory, gene expression and have less impact on HBV replication. [ABSTRACT FROM AUTHOR]

The relative importance of atmospheric advection and local land--atmosphere coupling to Australian precipitation is uncertain. Identifying the evaporative source regions and level of precipitation recycling can help quantify the importance of local and remote marine and terrestrial moisture to precipitation within the different hydroclimates across Australia. Using a three-dimensional Lagrangian back-trajectory approach, moisture from precipitation events across Australia during 1979-2013 was tracked to determine the source of moisture (the evaporative origin) and level of precipitation recycling. We show that source regions vary markedly for precipitation falling in different regions. Advected marine moisture was relatively more important than terrestrial contributions for precipitation in all regions and seasons. For Australia as a whole, contributions from precipitation recycling varied from ~11% in winter up to ~21% in summer. The strongest land--atmosphere coupling was in the northwest and southeast where recycled local land evapotranspiration accounted for an average of 9% of warm-season precipitation. Marine contributions to precipitation in the northwest of Australia increased in spring and, coupled with positive evaporation trends in the key source regions, suggest that the observed precipitation increase is the result of intensified evaporation in the Maritime Continent and Indian and Pacific Oceans. Less clear were the processes behind an observed shift in moisture contribution from winter to summer in southeastern Australia. Establishing the climatological source regions and the magnitude of moisture recycling enables future investigation of anomalous precipitation during extreme periods and provides further insight into the processes driving Australia's variable precipitation. [ABSTRACT FROM AUTHOR]

Stick-slip flow is a challenging viscoelastic benchmark problem due to the presence of a separation or transition point at the die exit where a sudden change in flow boundary conditions occurs. We present numerical simulations of transient planar stick-slip flow of the Phan-Thien–Tanner (PTT) and Giesekus fluids, investigating the polymer stress behavior around the stress singularity at the stick-slip point, confirming the asymptotic results presented by Evans et al. ["Stresses of the Oldroyd-B, PTT and Giesekus fluids in a Newtonian velocity field near the stick-slip singularity," Phys. Fluids 29, 1–33 (2017)]. In order to improve the numerical knowledge about this viscoelastic benchmark problem, two distinct mathematical methodologies are used for comparison in the computational simulations: the Cartesian and natural stress formulations. The former is widely applied in computational rheology, while the latter is used for the first time in the context of this problem. The natural stress formulation gives improved convergence results both temporally and spatially near to the singularity while maintaining the same global flow characteristics as the Cartesian. [ABSTRACT FROM AUTHOR]

Within the framework of a realistic atomistic lattice-gas model, we present the theoretical formulation and simulation procedures for precise analysis of the chemical diffusion flux of highly mobile CO within a nonuniform interacting mixed CO+O adlayer on a Pd(100) surface. The approach applies in both regimes of relatively immobile unequilibrated and fairly mobile near-equilibrated O adlayer distributions. Spatiotemporal behavior in surface reactions is controlled by chemical diffusion in mixed adlayers. Thus, we naturally integrate the above analysis with a previously developed multiscale modeling strategy to describe mesoscale reaction front propagation in CO oxidation on Pd(100). This treatment avoids using a simplified prescription of chemical diffusion and reaction kinetics as in traditional mean-field reaction-diffusion equation approaches. [ABSTRACT FROM AUTHOR]

We have developed an atomistic lattice-gas model for the catalytic oxidation of CO on single-crystal Pd(100) surfaces under ultrahigh vacuum conditions. This model necessarily incorporates an detailed description of adlayer ordering and adsorption-desorption kinetics both for CO on Pd(100), and for oxygen on Pd(100). Relevant energetic parameters are determined by comparing model predictions with experiment, together with some guidance from density functional theory calculations. The latter also facilitates description of the interaction and reaction of adsorbed CO and oxygen. Kinetic Monte Carlo simulations of this reaction model are performed to predict temperature-programed reaction spectra, as well as steady-state bifurcation behavior. [ABSTRACT FROM AUTHOR]

Preexposure to molecular oxygen gas, O[SUB2,g], can have a strong effect on the nucleation and growth of Ag islands on Ag(100) at 250 K. At this temperature, molecular oxygen dissociates efficiently at kink sites on steps. Subsequent deposition of Ag produces a far lower density of Ag[SUBad] islands than without oxygen. There is an associated increase in the Ag flux-scaling exponent, from 0.28 for the oxygen-free surface to 0.9 for the preexposed surface. Two-step deposition experiments show that species containing atomic oxygen diffuse freely across terraces and steps at this temperature and on the time scale of deposition. We hypothesize that the nucleating species contains both Ag and O, and that nucleation of islands is highly reversible (critical size i≫1). The diffusion of small islands, if it occurs, is not sufficient to explain the data. [ABSTRACT FROM AUTHOR]

We analyze fluctuations in a "hybrid" atomistic model mimicking CO oxidation on nanoscale facets of metal(100) catalyst surfaces. The model incorporates a mean-field-like treatment of infinitely mobile CO, and a lattice-gas treatment of the superlattice ordering of immobile O. For an infinite system, it exhibits an Ising-type order-disorder transition for O, together with mean-field-like bistability disappearing at a cusp bifurcation. For finite systems, we use kinetic Monte Carlo simulation to study the probability distribution for the population of adsorbed species, from which bistability can be observed, together with fluctuation-induced transitions between the two stable states. An effective potential picture emerges from our analyses that can be used to quantify both the system size dependence of fluctuations and the transition rates. Thus, our hybrid atomistic model displays fluctuation behavior analogous to traditional mean-field models. This qualitative behavior can be understood by approximate treatments of population dynamics using master equations and Fokker-Planck equations. A generalized model with finite mobility of CO is also analyzed for comparison with the hybrid model. In contrast, it exhibits fluctuation behavior akin to equilibrium systems with Ising-type first-order transitions. [ABSTRACT FROM AUTHOR]

Let p , q be primes such that q | p − 1 ⁠. Write F n for the free group of rank n ≥ 1 and let G (p , q) = C p ⋊ C q ⁠. We show that any stably free module over Z [ G (p , q) × F n ] is necessarily free. [ABSTRACT FROM AUTHOR]

Strontium (Sr) isotope analysis of archaeological crops is a potential method of provenancing and identifying the movement of crops in the past, but there remains uncertainty about whether original 87Sr/86Sr values can be obtained from carbonized buried grains. We have determined that hydrochloric acid (HCl) leaching removes some, but not all, exogenous Sr from carbonized cereal grains buried in soil for up to one year. We conclude that while further work could refine the leaching method, Sr isotope analysis of archaeological cereal grains can distinguish crops sourced from outside a particular (e.g., local) area if it can be shown that leaching moves grain 87Sr/86Sr values significantly away from the expected Sr signature. [ABSTRACT FROM AUTHOR]

Lead analysis of tooth enamel from individuals recovered from a Viking Age burial pit in southern England provides further evidence for their childhood origins outside Britain. All except one of the men have very low Pb concentrations that exclude anthropogenic Pb exposure. Strontium and oxygen isotope compositions identify a core group of men who have Pb isotope compositions of 208Pb/206Pb = 2.065 ± 0.021 (n = 20, 2SD) that, when compared with data from European soils, appear to exclude a childhood in the Scandinavian countries of Norway, Sweden and Finland, whereas areas of Northern continental Europe cannot be excluded. [ABSTRACT FROM AUTHOR]

During CO-oxidation on Pt(100), CO diffuses in a ‘‘disordered environment’’ produced by a complex pattern of reconstructed and unreconstructed regions of the substrate. Macroscopic diffusion of CO is effectively only possible on percolating 1×1-regions of the substrate. We treat the spatio-temporal behavior observed in this reaction system accounting in the simple way for the percolative nature of CO-diffusion. This is done via incorporation into the reaction-diffusion equations of a suitable chemical diffusion coefficient, exploiting ideas from the theory of transport in disordered media. We use these equations to analyze the propagation of reactive, O-rich pulses into a CO-covered 1×1-background. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We report the direct femtosecond measurements of the electron transfer process from CdS to TiO2 particles in a coupled colloidal system. The electrons initially created in the conduction band and quickly trapped at the liquid–solid interface in aqueous CdS colloids are found to be transferred to the colloidal TiO2 particles with a time constant of 2 ps, resulting in significantly slower electron–hole recombination. These coupled semiconductor colloids provide a potentially useful system for achieving efficient charge separation, which is important for many chemical reactions involving heterogeneous electron transfer. [ABSTRACT FROM AUTHOR]

We provide a unified discussion of kinetic phase transitions for mean-field and lattice–gas treatments of the monomer–dimer surface reaction. For high surface mobilities, kinetics is typically well described by mean-field rate equations. These reveal bistability over a range of monomer adsorption rates which diminishes with increasing nonreactive monomer desorption rate d, and vanishes at some critical d=dc. Relative stability in the bistable region is determined from the behavior of chemical waves corresponding to the displacement of one stable state by the other. Their evolution is determined via appropriate reaction–diffusion equations. Conventional diffusion terms are modified here to reflect the influence of the presence of one species on diffusion of the other. We determine equistability (i.e., discontinuous transition) points for d≤dc, and thus construct a kinetic phase diagram including a spinodal line. For lower surface mobilities, analysis of lattice–gas models reveals qualitatively analogous behavior. The key difference is that for lower mobilities, spontaneous fluctuations are effective in automatically selecting the most stable state, i.e., in reducing metastability, and thus producing discontinuous transitions. [ABSTRACT FROM AUTHOR]

Details the observation of magneto-optical transitions in a silicon center δ-doped quantum well. Effect of the ionized donors in the well on the optical spectra; Information on the two principle effects arising from the δ-doping sheet in the well; Details of the detection wavelength for the photoluminescence excitation (PLE) measurements; Description of the magneto-PLE spectra.

Examines the growth of small sinusoidal perturbations by viscous flow or by evaporation/condensation. Stability of a cylindrical pore in an infinite medium; Dependence of perturbation growth rate on perturbation wavelength; Rate limited by the sublimation and condensation at the surface.

Dissociative adsorption of oxygen on certain (100) metal surfaces has been modeled as random dimer adsorption onto diagonally adjacent empty sites of a square lattice subject to the additional constraint that all six neighboring sites must be empty (the 8-site model). Here we adapt this model to analyze the nonequilibrium c(2×2) ordering recently observed for oxygen on Pd(100) at coverages up to saturation (>1/4 monolayer), under conditions of low temperature and high pressure where effects of diffusive mobility can be ignored. We do, however, propose that adsorption could be followed immediately by short range transient mobility to dissipate excess energy. We first show how exact master equations for this model can be used to obtain analytic expressions for various local quantities of interest: the probability of an empty 8-site configuration (which determines the sticking coefficient), the c(2×2) island edge or domain boundary densities, etc. They also provide a characterization of, e.g., the asymptotic decay of spatial correlations. Near-percolating (percolative) c(2×2) ordering is readily observed in computer simulations of the saturation state. Through a simple extension of the physical model, we provide a framework for analysis of the large scale characteristics of this ordering via correlated polychromatic percolation theory. Corresponding scaling relations and some real space renormalization group analysis are described. Simulation results for average sizes, the effective dimension, and perimeter length to size ratios, of c(2×2) islands, are also presented. [ABSTRACT FROM AUTHOR]

A two-Hilbert space formalism is first used to develop a general class of representations for the quantum mechanics of N-particle reactive systems. Here the N-particle Hilbert space HN is supplemented by a larger arrangement channel space CN of vectors with Hilbert space valued components for each N-particle clustering, and an injection mapping of HN vectors into ‘‘physical’’ CN vectors. Such representations, for which components of the latter vectors carry an appropriate physical clustering interpretation, provide a rigorous and flexible basis for describing the statistical mechanics of reactive fluids, where atoms and molecules are treated on an equal footing (the molecular picture). Corresponding equilibrium multispecies fugacity or virial expansions follow immediately. Here we focus on analysis of the (previously derived) arrangement channel BBGKY hierarchy for a system where recombination and dissociation, as well as exchange reactions, occur. This formulation (coupled with a corresponding scattering theory) automatically suggests a reactive Boltzmann ansatz which incorporates (standard) noninteracting asymptotic dynamics only for two-molecule nonreactive and reactive exchange collisions. In contrast, e.g., with three molecule recombination, two-molecule dynamics for all three pairs is included (as required for a description of recombination via gradual stabilization of metastables). Finally we compare the resulting reduced form of appropriate channel space hierarchy equations, for a process involving dimer formation and decay, with the corresponding kinetic equations of Lowry and Snider. [ABSTRACT FROM AUTHOR]

Models where pairs, triples, or larger (typically connected) sets of sites on a 2D lattice ‘‘fill’’ irreversibly (described here as dimer, trimer, ... filling or adsorption), either randomly or cooperatively, are required to describe many surface adsorption and reaction processes. Since filling is assumed to be irreversible and immobile (species are ‘‘frozen’’ once adsorbed), even the stationary, saturation state, which is nontrivial since the lattice cannot fill completely, is not in equilibrium. The kinetics and statistics of these processes are naturally described by recasting the master equations in hierarchic form for probabilities of subconfigurations of empty sites. These hierarchies are infinite for the infinite lattices considered here, but approximate solutions can be obtained by implementing truncation procedures. Those used here exploit a shielding property of suitable walls of empty sites peculiar to irreversible filling processes. Accurate results, including saturation coverage estimates, are presented for random filling of dimers, and trimers of different shapes, on various infinite 2D lattices, and for square tetramers on an infinite square lattice. [ABSTRACT FROM AUTHOR]

This article draws on the philosophy of Deleuze and Guattari to reconceptualise transition to Higher Education. In doing so it contributes a new theoretical approach to understanding transition to Higher Education which largely remains under-theorised, uncritical and taken-for-granted. Drawing on data from two projects, the article activates Deleuze and Guattari’s concepts of assemblage, rhizome and becoming to contest the established view of transition as a linear pathway or series of ‘critical incidents’. The article illuminates how Deleuze and Guattari’s concepts are of value both in theorising the multiplicity and heterogeneity of transition and in refocusing attention on the lived specificities of students’ experiences within a complex web of institutional and affective practices. The article ends with a consideration of how Deleuze and Guattari recast understandings of transitions theory and practice. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance is primarily a problem in human medicine but there are unquantified links of transmission in both directions between animal and human populations. Quantitative assessment of the costs and benefits of reduced antimicrobial usage in livestock requires robust quantification of transmission of resistance between animals, the environment and the human population. This in turn requires appropriate measurement of resistance. To tackle this we selected two different methods for determining whether a sample is resistant − one based on screening a sample, the other on testing individual isolates. Our overall objective was to explore the differences arising from choice of measurement. A literature search demonstrated the widespread use of testing of individual isolates. The first aim of this study was to compare, quantitatively, sample level and isolate level screening. Cattle or sheep faecal samples (n = 41) submitted for routine parasitology were tested for antimicrobial resistance in two ways: (1) “streak” direct culture onto plates containing the antimicrobial of interest; (2) determination of minimum inhibitory concentration (MIC) of 8–10 isolates per sample compared to published MIC thresholds. Two antibiotics (ampicillin and nalidixic acid) were tested. With ampicillin, direct culture resulted in more than double the number of resistant samples than the MIC method based on eight individual isolates. The second aim of this study was to demonstrate the utility of the observed relationship between these two measures of antimicrobial resistance to re-estimate the prevalence of antimicrobial resistance from a previous study, in which we had used “streak” cultures. Boot-strap methods were used to estimate the proportion of samples that would have tested resistant in the historic study, had we used the isolate-based MIC method instead. Our boot-strap results indicate that our estimates of prevalence of antimicrobial resistance would have been considerably lower in the historic study had the MIC method been used. Finally we conclude that there is no single way of defining a sample as resistant to an antimicrobial agent. The method used greatly affects the estimated prevalence of antimicrobial resistance in a sampled population of animals, thus potentially resulting in misleading results. Comparing methods on the same samples allows us to re-estimate the prevalence from other studies, had other methods for determining resistance been used. The results of this study highlight the importance of establishing what the most appropriate measure of antimicrobial resistance is, for the proposed purpose of the results. [ABSTRACT FROM AUTHOR]

We characterise the stress singularity of the Oldroyd-B, Phan-Thien-Tanner (PTT), and Giesekus viscoelastic models in steady planar stick-slip flows. For both PTT and Giesekus models in the presence of a solvent viscosity, the asymptotics show that the velocity field is Newtonian dominated near to the singularity at the join of the stick and slip surfaces. Polymer stress boundary layers are present at both the stick and slip surfaces. By integrating along streamlines, we verify the polymer stress behavior of rr4/11 for PTT and rr5/16 for Giesekus, where r is the radial distance from the singularity. These asymptotic results for PTT and Giesekus do not hold in the limit of vanishing quadratic stress terms for Oldroyd-B. However, we can consider the Oldroyd-B model in the fixed kinematics of a prescribed Newtonian velocity field. In contrast to PTT and Giesekus, this is not the correct balance for the momentum equation but does allow insight into the behavior of the Oldroyd-B equations near the singularity. A three-region asymptotic structure is again apparent with now a polymer stress singularity of rr4/5. The high Weissenberg boundary layer equations are found to manifest themselves at the stick surface and are of thickness r3/2. At the slip surface, dominant balance between the upper convected stress and rate-of-strain terms gives a slip boundary layer of thickness r2. The solution of the slip boundary layer shows that the polymer stress is now singular along the slip surface. These results are supported through numerical integration along streamlines of the Oldroyd-B equations in a Newtonian velocity field. The Oldroyd-B model thus extends the point singularity at the join of the stick and slip surfaces to the whole of slip surface. As such, it does not have a physically meaningful solution in a Newtonian velocity field. We would expect a similar stress behavior for this model in the true viscoelastic velocity field. [ABSTRACT FROM AUTHOR]

The two-dimensional isolation oxidation of silicon is considered for stress-dependent reaction and diffusion coefficients. The influence of such parameters is investigated numerically and asymptotically in the bird's beak problem and for curved geometries arising in the oxidation of cylindrical and spherical structures. In the bird's beak problem, the limit of large activation volume is described for a stress-dependent reaction coefficient, illustrating the significant growth retardation of the silicon/silicon oxide interface and reduced stresses in the silicon oxide. Novel high-order nonlinear evolution-type PDEs are derived and investigated using asympt otic and numerical techniques. [ABSTRACT FROM AUTHOR]

BackgroundCapturing service users’ perspectives can highlight additional and different concerns to those of clinicians, but there are no up to date, self-report psychometrically sound measures of side effects of antipsychotic medications.AimTo develop a psychometrically sound measure to identify antipsychotic side effects important to service users, the Maudsley Side Effects (MSE) measure.MethodAn initial item bank was subjected to a Delphi exercise (n = 9) with psychiatrists and pharmacists, followed by service user focus groups and expert panels (n = 15) to determine item relevance and language. Feasibility and comprehensive psychometric properties were established in two samples (N43 and N50). We investigated whether we could predict the three most important side effects for individuals from their frequency, severity and life impact.ResultsMSE is a 53-item measure with good reliability and validity. Poorer mental and physical health, but not psychotic symptoms, was related to side-effect burden. Seventy-nine percent of items were chosen as one of the three most important effects. Severity, impact and distress only predicted ‘putting on weight’ which was more distressing, more severe and had more life impact in those for whom it was most important.ConclusionsMSE is a self-report questionnaire that identifies reliably the side-effect burden as experienced by patients. Identifying key side effects important to patients can act as a starting point for joint decision making on the type and the dose of medication. [ABSTRACT FROM PUBLISHER]

NARCliM (New South Wales (NSW)/Australian Capital Territory (ACT) Regional Climate Modelling project) is a regional climate modeling project for the Australian area. It is providing a comprehensive dynamically downscaled climate dataset for the CORDEX-AustralAsia region at 50-km resolution, and south-East Australia at a resolution of 10 km. The first phase of NARCliM produced 60-year long reanalysis driven regional simulations to allow evaluation of the regional model performance. This long control period (1950-2009) was used so that the model ability to capture the impact of large scale climate modes on Australian climate could be examined. Simulations are evaluated using a gridded observational dataset. Results show that using model independence as a criteria for choosing atmospheric model configuration from different possible sets of parameterizations may contribute to the regional climate models having different overall biases. The regional models generally capture the regional climate response to large-scale modes better than the driving reanalysis, though no regional model improves on all aspects of the simulated climate. [ABSTRACT FROM AUTHOR]

Infectious agents and their associated diseases can be significant barriers in the production of poultry and zoonotic agents associated with poultry flocks can ultimately endanger consumers. To this end, poultry producers employ a variety of strategies to minimize associated risks. Disinfectants are widely utilized in the poultry industry to limit encounters with avian pathogens and zoonotic agents. These disinfectants are readily applied by a variety of means to both equipment and facilities to reduce pathogenic populations and minimize their associated risk. While a variety of disinfectants and application means are currently available, the search for more efficacious products and technologies continues. Recently, technology has been developed that may be applicable to the poultry industry for pathogen reduction. The NebuPure™ disinfecting system was developed as a means to decontaminate facilities harboring human pathogens. The system utilizes a novel dispersal unit to suspend an electrochemically activated solution in enclosed facilities and allows for largely automated decontamination. To test the NebuPure™ disinfecting system for poultry-related applications, a research facility was seeded with plate cultures of the avian respiratory pathogen Mycoplasma gallisepticum (MG). The facility was then treated with the NebuPure™ disinfecting system with exposure times of 1 or 4 h. Following incubation, no growth was observed among exposed plates, while control plates were 100% positive for MG. The research demonstrates the efficacy of the NebuPure™ disinfecting system for disinfecting MG-contaminated facilities and indicates that the system may be used against other poultry-associated pathogens. [ABSTRACT FROM AUTHOR]

Previous pilot work has established an association between obstructive sleep apnoea and the development of acute postoperative delirium , but it remains unclear to what extent this risk factor is modifiable in the 'real world' peri-operative setting. In a single-blind randomised controlled trial, 135 elderly surgical patients at risk for obstructive sleep apnoea were randomly assigned to receive peri-operative continuous positive airway pressure (CPAP) or routine care. Of the 114 patients who completed the study, 21 (18.4%) experienced delirium. Delirium was equally common in both groups: 21% (12 of 58 subjects) in the CPAP group and 16% (9 of 56 subjects) in the routine care group (OR = 1.36 [95%CI 0.52-3.54], p = 0.53). Delirious subjects were slightly older - mean (SD) age 68.9 (10.7) vs. 64.9 (8.2), p = 0.07 - but had nearly identical pre-operative STOP-Bang scores (4.19 (1.1) versus 4.27 (1.3), p = 0.79). Subjects in the CPAP group used their devices for a median (IQR [range]) of 3 (0.25-5 [0-12]) nights pre-operatively (2.9 (0.1-4.8 [0.0-12.7]) hours per night) and 1 (0-2 [0-2]) nights postoperatively (1.4 (0.0-5.1 [0.0-11.6]) hours per night). Among the CPAP subjects, the residual pre-operative apnoea-hypopnea index had a significant effect on delirium severity (p = 0.0002). Although we confirm that apnoea is associated with postoperative delirium, we did not find that providing a short-course of auto-titrating CPAP affected its likelihood or severity. Voluntary adherence to CPAP is particularly poor during the initiation of therapy. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop an automated calibration process for a galvanic cell type oxygen sensor. The manufacturer recommended a two-point calibration at room temperature; however, testing revealed that the response was not linear when both the temperature and oxygen concentrations varied. Thus, additional points were needed to generate a representative calibration equation and to reduce the sensor prediction interval. The calibration process needed to be capable of automatically recording sensor response (voltage) at an array of temperatures and oxygen concentrations. Calibration gases were used to precisely control the oxygen concentration inside a small manifold, and an electronically controlled water bath was used to regulate the sensor and gas temperature. A custom computer program controlled the sampling order and the data collection process. The responses for three sensors were recorded at six temperature (10°C, 20°C, 30°C, 40°C, 50°C, and 60°C) and five oxygen concentration (0%, 5%, 10%, 15%, and 20% O2 absolute) combinations, for a total of 30 measurements per calibration. Calibration data were used to create a second-degree polynomial model with oxygen sensor voltage and temperature as input parameters, which reduced the prediction interval by over 1% O2 for each of the three sensors tested. The resulting prediction intervals ranged between 0.75% and 0.95% O2. Three sensors were mounted in a prototype oxygen probe and tested under controlled conditions to demonstrate the ability to measure oxygen concentration versus depth in a composting environment. [ABSTRACT FROM AUTHOR]

Risk assessment and behavioral responses to predation can depend on demographic and environmental factors. We studied the escape behavior of the sand-diving lizard Meroles anchietae in the Namib Desert, using simulated predator approaches and measuring latency to burying in sand. Lizards showed a clear preference for burying on a slipface. Flight initiation distance was largely influenced by the starting distance separating the lizard and pursuer, and whether the animal was initially sighted on or off a slipface. In general, longer starting distances were associated with longer flight initiation distances. The total flight distance covered by lizards before burying was inversely related to body size, and positively related to initial distance from a slipface crest. Distance from a slipface crest was associated with increased total flight distance, most dramatically for those initially sighted on a dune slipface. Even when shelter is ubiquitous, sand-dive patterns depend on location on a dune and body condition. [ABSTRACT FROM AUTHOR]

The article focuses on the encounter of author Søren Kierkegaard with the Richard Wagner's opera "Tannhäuser," focusing on his esthete writing about Tannhäuser and its two categories of Christian spirit and erotic sesuality in the form of the Virgin Mary and Venus, relative to his book "Either/or: A Fragment of Life." It discusses the cinnections between the legends of Don Juan and Mount Venus, and the epxloration of the Wolfgang Amadeus Mozart Mozart's "Don Giovanni."

The current trend to treat hypotension in critically ill patients is to place a greater emphasis on inotropic support and less on fluid resuscitation in order to limit the potential harm from fluid overload. This combination may trigger left ventricular outflow tract obstruction (LVOTO) in susceptible patients. Although LVOTO is classically described in patients with hypertrophic cardiomyopathy it has been reported in other conditions including septic shock, apical ballooning syndrome, myocardial infarction, respiratory failure, and post valvular surgery. It is more common in the elderly, females, and in patients with hypertension, diabetes, and chronic vascular disease because of predisposing anatomical conditions such as left ventricular hypertrophy, small left ventricle size, sigmoid septum and alterations in the positions of the aortic and mitral valve annular planes. The onset of LVOTO is largely unpredictable due to a complex interplay between preload, afterload, heart rhythm and rate in susceptible patients. The consequences of missing this treatable condition may lead to life-threatening hypotension refractory to, or exacerbated by, a further increase in inotropic support. Dynamic LVOTO should be considered in any hypotensive intensive care patient. Echocardiography is perhaps the best tool to assess LVOTO and its underlying pathophysiology in the critically ill. Detection of LVOTO is a relatively simple task using a combination of two-dimensional, M-mode and spectral Doppler imaging by an operator alert to the possible diagnosis. [ABSTRACT FROM AUTHOR]

It is well known that sexual selection can target reproductive traits during successive pre- and post-mating episodes of selection. A key focus of recent studies has been to understand and quantify how these episodes of sexual selection interact to determine overall variance in reproductive success. In this article, we review empirical developments in this field but also highlight the considerable variability in patterns of pre- and post-mating sexual selection, attributable to variation in patterns of resource acquisition and allocation, ecological and social factors, genotype-by-environment interaction and possible methodological factors that might obscure such patterns. Our aim is to highlight how (co)variances in pre- and post-mating sexually selected traits can be sensitive to changes in a range of ecological and environmental variables. We argue that failure to capture this variation when quantifying the opportunity for sexual selection may lead to erroneous conclusions about the strength, direction or form of sexual selection operating on pre- and post-mating traits. Overall, we advocate for approaches that combine measures of pre- and post-mating selection across contrasting environmental or ecological gradients to better understand the dynamics of sexual selection in polyandrous species. We also discuss some directions for future research in this area. [ABSTRACT FROM AUTHOR]

This study presents results from regional climate model (RCM) projections for the south-west Pacific Ocean. The regional models used bias corrected sea surface temperatures. Six global climate models (GCMs) were used to drive a global variable resolution model on a quasi-uniform 60 km grid. One of these simulations was used to drive three limited area regional models. Thus a four member ensemble was produced by different RCMs downscaling the same GCM (GFDL2.1), and a six member ensemble was produced by the same RCM (Conformal Cubic Atmospheric Model-CCAM) downscaling six different GCMs. Comparison of the model results with precipitation observations shows the differences to be dominated by the choice of RCM, with all the CCAM simulations performing similarly and generally having lower error than the other RCMs. However, evaluating aspects of the model representation of the South Pacific Convergence Zone (SPCZ) does not show CCAM to perform better in this regard. In terms of the future projections of the SPCZ for the December-January-February season, the ensemble showed no consensus change in most characteristics though a majority of the ensemble members project a decrease in the SPCZ strength. Thus, similar to GCM based studies, there is large uncertainty concerning future changes in the SPCZ and there is no evidence to suggest that future changes will be outside the natural variability. These RCM simulations do not support an increase in the frequency of zonal SPCZ events. [ABSTRACT FROM AUTHOR]

Dental technology programmes of study must prepare students to practice in a broad range of contemporary workplaces. Currently, there is limited evidence to benchmark dental technology education - locally, nationally or internationally. This research aims to improve consistency, transparency and portability of dental technology qualifications across three countries. Data were accessed from open-source curriculum documents and five calibrated assessment items. Three institutions collaborated with Oslo and Akershus University College, Norway; Trinity College Dublin, Ireland; and Griffith University, Australia. From these, 29-44 students completed 174 assessments. The curricula reflect the community needs of each country and display common themes that underpin professional dental technology practice. Assessment results differed between institutions but no more than a normal distribution. Face-to-face assessment moderation was critical to achieve consistency. This collaborative research has led to the development of a set of guidelines for other dental technology education providers interested in developing or aligning courses internationally to enhance the portability of qualifications. [ABSTRACT FROM AUTHOR]

The diffusionless ZGB (monomer–dimer) surface reaction model exhibits a discontinuous transition to a monomer-poisoned state when the fraction of monomer adsorption attempts exceeds 0.525. It has been claimed that this transition shifts to 2/3 with introduction of rapid diffusion of the monomer species, or of both species. We show this is not the case, 2/3 representing the spinodal rather than the transition point. For equal diffusion rates of both species, we find that the transition only shifts to 0.5951±0.0002. [ABSTRACT FROM AUTHOR]

Various features of NO+CO reaction kinetics on Pt(100) surfaces, including temporal oscillations, are well described by a three-variable model incorporating only the CO, NO, and O coverages. Here we analyze the corresponding reaction–diffusion equations demonstrating the existence of chemical waves where an ‘‘oscillating phase’’ displaces an unreactive NO/CO phase leaving a spatially periodic structure in its wake; pulses excited via inhomogeneities from an unreactive NO/CO background; and Turing structures for sufficiently unequal NO and CO diffusion rates. [ABSTRACT FROM AUTHOR]

The 2022 Tongan volcanic eruption released significant energy into the atmosphere. Tropospheric satellite images show that the eruption generated pressure waves that traveled globally. The Global Observation of the Limb and Disk (GOLD) mission observed significant wave‐like thermospheric temperature perturbations (>100 K) from 12 to 16 UT. These temperature perturbations' spatial curvatures and arrival times are initially similar to the tropospheric wave‐fronts but differ significantly with eastward propagation. The perturbations had a phase speed of ∼300–400 m/s and wavelengths greater than 2,400 km. Near‐concurrent Ionospheric Connection Explorer neutral wind measurements suggest that the eruption's effects reversed the direction of the prevailing thermospheric zonal winds around the perturbed regions. The eruption's global and whole atmospheric effects provide a unique opportunity to study how different atmospheric layers exchange energy and momentum during explosive events. GOLD's synoptic observations are uniquely positioned to study these effects in the middle thermosphere. Plain Language Summary: The powerful Hunga Tonga‐Hunga Ha'apai volcanic eruption on 15 January 2022, at 4:15 UT was visible from space. Satellite images in the troposphere (near 10 km altitude) show concentric pressure waves emanating from the eruption center that travel globally. Wave signatures were seen across multiple atmospheric layers. NASA's Global‐scale Observations of Limb and Disk mission observed its signatures near 150 km altitude as neutral temperature perturbations. Explosive events that affect multiple atmospheric layers allow us to observe how the different atmospheric layers exchange energy and momentum in response to an impulsive source. In this paper, we present an analysis of the eruption induced temperature perturbation in the middle thermosphere. Key Points: Global‐scale Observations of Limb and Disk mission observed global‐scale thermospheric neutral temperature perturbations (>100 K) induced by the Tongan volcanic eruptionThe phase speeds of the perturbations are around 300–400 m/s with a large wavelength (>2,400 km)The zonal winds near the peak temperature perturbation reverse from eastward to westward [ABSTRACT FROM AUTHOR]

The objective of this study was to test the feasibility of using coverage measurements from water-sensitive spray cards to estimate the volumetric flow rate at an individual sprayer nozzle. TeeJet VisiFlow Even Flat Spray Tips were selected due to their uniform distribution of coverage. Spray distribution for each nozzle was validated using a spray patternator table with 2.5 cm sampling widths. A rotary test fixture translated water-sensitive spray cards through the spray dispersion (water at ambient conditions) at a constant angular velocity and a radius of 1.2 m. The test fixture measured volumetric flow and pressure at the nozzle and recorded data at a rate of 10 Hz. A helical gear pump and a pistontype pressure regulating valve were used to provide constant pressure. The first experiment fixed the test fixture speed at 3.14 rad s-1 and used varying pressures from 70 to 552 kPa (10 to 80 psi) in 70 kPa (10 psi) increments. First-order and second-order regression models were developed for the nozzle series, and validation data were collected at intermediate pressures to test the ability of the model to predict volumetric flow rates. The second experiment fixed the system pressure at 310 kPa (45 psi) and varied the speed of the test fixture at seven increments between 2.0 and 3.8 rad s-1. Spray cards were digitized using a scanner and processed for coverage using the MATLAB image processing toolbox. Results showed that the accuracy of the spray card method was within 1% full-scale of a commercial impeller flowmeter for a single series of nozzles moving at constant speed. Varying speed could be accounted for but required knowledge of the individual nozzle model. The method demonstrated in this study may be useful for field validation of variable-rate control systems on agricultural sprayers. [ABSTRACT FROM AUTHOR]