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Quantum imaging exemplifies the fascinating and counter‐intuitive nature of the quantum world, where non‐local correlations are exploited for imaging of objects by remote and non‐interacting photons. The field has exploded of late, driven by advances in our fundamental understanding of these processes, but also by advances in technology, for instance, efficient single photon detectors and cameras. Accelerating the progress is the nascent intersection of quantum imaging with artificial intelligence and machine learning, promising enhanced speed and quality of quantum images. This review provides a comprehensive overview of the rapidly evolving field of quantum imaging with a specific focus on the intersection of quantum ghost imaging with artificial intelligence and machine learning techniques. The seminal advances made to date and the open challenges are highlighted, and the likely trajectory for the future is outlined. [ABSTRACT FROM AUTHOR]

Quantum photonic platforms have proven to be essential in realizing fundamentally secure quantum transfer of information, with commercially ready systems already deployed in municipal and terrestrial links. The drive toward higher bit rates and robustness to eavesdropping and noisy channels has focused attention on moving from the present two-dimensional quantum states of polarization, to harnessing all of light's degrees of freedom for multi-dimensional quantum coding with structured photons. In this Perspective, we outline the present state-of-the-art in achieving this control with spatial modes of light, both as single photon and entangled states, highlight the open challenges that remain, and consider the roadmap that might see its full potential realized. [ABSTRACT FROM AUTHOR]

This article introduces the 'staircase' design, derived from the zigzag pattern of steps along the diagonal of a stepped wedge design schematic where clusters switch from control to intervention conditions. Unlike a complete stepped wedge design where all participating clusters must collect and provide data for the entire trial duration, clusters in a staircase design are only required to be involved and collect data for a limited number of pre- and post-switch periods. This could alleviate some of the burden on participating clusters, encouraging involvement in the trial and reducing the likelihood of attrition. Staircase designs are already being implemented, although in the absence of a dedicated methodology, approaches to sample size and power calculations have been inconsistent. We provide expressions for the variance of the treatment effect estimator when a linear mixed model for an outcome is assumed for the analysis of staircase designs in order to enable appropriate sample size and power calculations. These include explicit variance expressions for basic staircase designs with one pre- and one post-switch measurement period. We show how the variance of the treatment effect estimator is related to key design parameters and demonstrate power calculations for examples based on a real trial. [ABSTRACT FROM AUTHOR]

Thin films of ferromagnet F e 2 Ge were grown via molecular beam epitaxy, and their electrical and magneto-transport properties were measured for the first time. X-ray diffraction and vibrating sample magnetometry measurements confirmed the crystalline ferromagnetic F e 2 Ge phase. The observed high-temperature maximum in the longitudinal resistivity, as well as the observed suppression of electron–magnon scattering at low temperatures, points to the presence of strong spin polarization in this material. Measurements of the Hall resistivity, ρ x y , show contributions from both the ordinary Hall effect and the anomalous Hall effect, ρ x y A H , from which we determined the charge carrier concentration and mobility. Measurements also show a small negative magnetoresistance in both the longitudinal and transverse geometries. F e 2 Ge holds promise as a useful spintronic material, especially for its semiconductor compatibility. [ABSTRACT FROM AUTHOR]

Thin films of iron–tin alloy FeSn are grown on silicon substrates and their structural and transport properties are investigated for the first time. Herein, the molecular beam epitaxy method is used to grow 50 and 30 nm thick FeSn films on silicon substrates containing 10 nm of MgO as a buffer layer. The films are characterized structurally using an X‐ray diffractometer, showing a hexagonal crystal structure with the space group P6/mmm (191). The results from electrical and magnetotransport measurements show these films exhibit characteristics close to metals. Herein, the magnetotransport properties of the thin films which show positive magnetoresistance and sample‐dependent Hall effect with possible multiband transport are further measured. [ABSTRACT FROM AUTHOR]

Here we functionalized micro-scaled polymer beads with nano-scaled quantum dots and demonstrate optical trapping and tweezing, with in-situ fluorescence measurement, in an all-digital all-optical configuration. We outline the chemistry required to facilitate this, from deactivating the optical trapping environment to size, adhesion and agglomeration control. We introduce a novel holographic optical trapping set-up that leverages on vectorially structured light, allowing for the delivery of tuneable forms of light from purely scalar to purely vector, including propagation invariant flat-top beams for uniform illumination and tailored intensity gradient landscapes. Finally, we show how this has the potential to quench bleaching in a single wavelength trap by linear (spatial mode) rather than non-linear effects, advancing the nascent field of optics for chemistry. [ABSTRACT FROM AUTHOR]

Here we functionalized micro-scaled polymer beads with nano-scaled quantum dots and demonstrate optical trapping and tweezing, with in-situ fluorescence measurement, in an all-digital all-optical configuration. We outline the chemistry required to facilitate this, from deactivating the optical trapping environment to size, adhesion and agglomeration control. We introduce a novel holographic optical trapping set-up that leverages on vectorially structured light, allowing for the delivery of tuneable forms of light from purely scalar to purely vector, including propagation invariant flat-top beams for uniform illumination and tailored intensity gradient landscapes. Finally, we show how this has the potential to quench bleaching in a single wavelength trap by linear (spatial mode) rather than non-linear effects, advancing the nascent field of optics for chemistry. [ABSTRACT FROM AUTHOR]

Thin films of the high Curie temperature intermetallic ferromagnet β - Fe 2 Si were synthesized via molecular beam epitaxy. Investigation using X-ray diffraction and atomic force microscopy shows a hexagonal crystal structure and a smooth topography. Theoretically, Fe 2 Si has been predicted to exhibit uniquely desirable magnetotransport properties. We report on these properties experimentally, including the ordinary Hall coefficient R 0 and anomalous Hall resistivity ρ x y A H . The compound is found to be a soft Heisenberg ferromagnet with temperature dependent magnetization based on the thermal excitation of spin waves. We present a detailed look into the contributions to its longitudinal resistivity, which due to the presence of a spin-flip gap Δ k B , indicating a half-metallic band structure. The correct scaling relations between these components of the resistivity tensor (ρ x x and ρ x y ) are also discussed. [ABSTRACT FROM AUTHOR]

Quantum ghost imaging offers many advantages over classical imaging, including low photon fluxes and non-degenerate object and image wavelengths for imaging light sensitive structures, but suffers from slow image reconstruction speeds. Image reconstruction times depend on the resolution of the required image which scale quadratically with the image resolution. Here, we propose a super-resolved imaging approach based on neural networks where we reconstruct a low resolution image, which we denoise and super-resolve to a high resolution image. To test the approach, we implemented both a generative adversarial network as well as a super-resolving autoencoder in conjunction with an experimental quantum ghost imaging setup, demonstrating its efficacy across a range of object and imaging projective mask types. We achieved super-resolving enhancement of 4 × the measured resolution with a fidelity close to 90 % at an acquisition time of N 2 measurements, required for a complete N × N pixel image solution. This significant resolution enhancement is a step closer to a common ghost imaging goal, to reconstruct images with the highest resolution and the shortest possible acquisition time. [ABSTRACT FROM AUTHOR]

In cluster-randomized trials, sometimes the effect of the intervention being studied differs between clusters, commonly referred to as treatment effect heterogeneity. In the analysis of stepped wedge and cluster-randomized crossover trials, it is possible to include terms in outcome regression models to allow for such treatment effect heterogeneity yet this is not frequently considered. Outside of some simulation studies of specific cases where the outcome is binary, the impact of failing to include terms for treatment effect heterogeneity on the variance of the treatment effect estimator is unknown. We analytically examine the impact of failing to include terms for treatment effect heterogeneity on the variance of the treatment effect estimator, when outcomes are continuous. Using analysis of variance and feasible generalized least squares we provide expressions for this variance. For both the cluster-randomized crossover design and the stepped wedge design, our analytic derivations indicate that failing to include treatment effect heterogeneity results in the estimates for variance of the treatment effect that are too small, leading to inflation of type I error rates. We therefore recommend assessing the sensitivity of sample size calculations and conclusions drawn from the analysis of cluster randomized trials to the inclusion of treatment effect heterogeneity. [ABSTRACT FROM AUTHOR]

Background: Interrupted time series (ITS) studies are frequently used to evaluate the effects of population-level interventions or exposures. However, examination of the performance of statistical methods for this design has received relatively little attention.Methods: We simulated continuous data to compare the performance of a set of statistical methods under a range of scenarios which included different level and slope changes, varying lengths of series and magnitudes of lag-1 autocorrelation. We also examined the performance of the Durbin-Watson (DW) test for detecting autocorrelation.Results: All methods yielded unbiased estimates of the level and slope changes over all scenarios. The magnitude of autocorrelation was underestimated by all methods, however, restricted maximum likelihood (REML) yielded the least biased estimates. Underestimation of autocorrelation led to standard errors that were too small and coverage less than the nominal 95%. All methods performed better with longer time series, except for ordinary least squares (OLS) in the presence of autocorrelation and Newey-West for high values of autocorrelation. The DW test for the presence of autocorrelation performed poorly except for long series and large autocorrelation.Conclusions: From the methods evaluated, OLS was the preferred method in series with fewer than 12 points, while in longer series, REML was preferred. The DW test should not be relied upon to detect autocorrelation, except when the series is long. Care is needed when interpreting results from all methods, given confidence intervals will generally be too narrow. Further research is required to develop better performing methods for ITS, especially for short series. [ABSTRACT FROM AUTHOR]

Structured light, where optical beams are tailored in amplitude, phase and polarisation to some desired profile, has become topical of late, fuelled by the ease at which such fields can be created internal and external to the source. In this treatise, part I of a two part series, we consider the thermal effects (stress, lensing and phase aberrations) associated with high-power structured light, where the structure may be the pump, optically inducing the thermal effects in the medium, or the probe, experiencing thermally induced optical aberrations. We outline a general theory for arbitrary structured light pumps and probes, reducing to the prior studies of Gaussian and flat-top beams as special cases. We illustrate the power of the model using the structure of light as a new degree of freedom with which to mitigate thermally induced optical aberrations. Finally, in part II of this composite work (Scholes and Forbes, Appl Phys B, 2021. https://doi.org/10.1007/s00340-021-07656-z), we experimentally demonstrate the phase aberration predictions using a digital micro-mirror device for real-time simulation of such high-power thermal effects in a cheap, fast and versatile manner, without the need for elaborate high-power experiments. Our work brings together the disparate fields of thermal modelling and structured light, providing a framework for future work in the creation and delivery of high-power structured light fields. [ABSTRACT FROM AUTHOR]

In part I of this work (Scholes and Forbes, Appl Phys B, 2021. https://doi.org/10.1007/s00340-021-07657-y), we provided a general model for optically induced thermal aberrations due to high power structured light pumps, highlighting the implications for arbitrary structured probes. We showed how the thermal effects impact on various structured light fields, and illustrated how to mitigate these effects using the structure of light as a new degree of freedom for control. Here, in part II, we demonstrate that thermo-optical effects can be simulated experimentally with cheap and fast digital micro-mirror devices. This approach represents a fully configurable, versatile, low-power physical simulator which replicates all the salient effects seen with high power sources, the latter notoriously difficult to experiment with. We demonstrate the efficacy of this simulator with various structured light beams under realistic thermal conditions which we programme as phase-only computer generated holograms, effective because the pertinent thermal effects themselves are phase-only aberrations to the field. Our work provides a new means to simulate thermal aberrations due to high power lasers and could be extended to correction techniques too. [ABSTRACT FROM AUTHOR]

Objective: Evaluate the Pain Impact Index, a simple, brief, easy‐to‐use, and novel tool to assess the impact of chronic pain in community‐dwelling older adults. Methods: A Rasch modelling analysis was undertaken in Stata using a partial credit model suited to the Likert‐type items that comprised the Index. The Index was evaluated for ordering of category thresholds, unidimensionality, overall fit to the Rasch model, measurement bias (Differential Item Functioning, DIF), targeting, and construct validity. Results: The four‐item Pain Impact Index was self‐completed by 6454 community‐dwelling Australians who were aged at least 70 years and experienced pain on most days. Two items showed evidence of threshold disordering, and this was resolved by collapsing response categories (from 5 to 3) for all items. The rescored Index conformed to the unidimensionality assumption and had satisfactory fit with the Rasch model (analyses conducted on a reduced sample size to mitigate the potential for overpowering: n = 377, P > 0.0125, power > 77%). When considering uniform DIF, the most frequent sources of measurement bias were age, knee pain, and upper back pain. When considering nonuniform DIF, the most frequent source of measurement bias was knee pain. The Index had good ability to differentiate between respondents with different levels of pain impact and had highest measurement precision for respondents located around the average level of pain impact in the study sample. Both convergent and discriminant validity of the Index were supported. Conclusion: The Pain Impact Index showed evidence of unidimensionality, was able to successfully differentiate between levels of pain impact, and had good evidence of construct validity. [ABSTRACT FROM AUTHOR]

Context: Ankle immobilization is often used after ankle injury. Objective: To determine the influence of 1 week's unilateral ankle immobilization on plantar-flexor strength, balance, and walking gait in asymptomatic volunteers. Design: Repeated-measures laboratory study. Setting: University laboratory. Participants: 6 physically active male participants with no recent history of lower-limb injury. Interventions: Participants completed a 1-wk period of ankle immobilization achieved through wearing a below-knee ankle cast. Before the cast was applied, as well as immediately, 24 h, and 48 h after cast removal, their plantar-flexor strength was assessed isokinetically, and they completed a single-leg balance task as a measure of proprioceptive function. An analysis of their walking gait was also completed Main Outcome Measures: Peak plantar-flexor torque and balance were used to determine any effect on muscle strength and proprioception after cast removal. Ranges of motion (3D) of the ankle, knee, and hip, as well as walking speed, were used to assess any influence on walking gait. Results: After cast removal, plantar-flexor strength was reduced for the majority of participants (P = .063, CI = -33.98 to 1.31) and balance performance was reduced in the immobilized limb (P < .05, CI = 0.84-5.16). Both strength and balance were not significantly different from baseline levels by 48 h. Walking speed was not significantly different immediately after cast removal but increased progressively above baseline walking speed over the following 48 h. Joint ranges of motion were not significantly different at any time point. Conclusions: The reduction in strength and balance after such a short period of immobilization suggested compromised central and peripheral neural mechanisms. This suggestion appeared consistent with the delayed increase in walking speed that could occur as a result of the excitability of the neural pathways increasing toward baseline levels. [ABSTRACT FROM AUTHOR]

A new species of the parasitic wasp Coptera Say was previously distinguished from other species via correspondence between ecological (host) differences and DNA barcodes. A description and figures for Coptera tonic sp. nov., along with revisions to existing keys that allow it to be distinguished from other Nearctic species without the aid of molecular characters, is provided in this work. [ABSTRACT FROM AUTHOR]

Cynipid gall wasps play an important role in structuring oak arthropod communities. Wasps in the Cynipini tribe typically lay their eggs in oaks (Quercus L.), and induce the formation of a 'gall', which is a tumor-like growth of plant material that surrounds the developing wasp. As the wasp develops, the cynipid and its gall are attacked by a diverse community of natural enemies, including parasitoids, hyperparasitoids, and inquilines. Determining what structures these species-rich natural enemy communities across cynipid gall wasp species is a major question in gall wasp biology. Additionally, gall wasps are ecosystem engineers, as the abandoned gall is used by other invertebrates. The gall-associated insect communities residing on live oaks (Quercus geminata Small and Quercus virginiana Mill.) are emerging as a model system for answering ecological and evolutionary questions ranging from community ecology to the evolution of new species. Documenting the arthropods associated with cynipids in this system will expand our understanding of the mechanisms influencing eco-evolutionary processes, record underexplored axes of biodiversity, and facilitate future work. Here, we present the community of natural enemies and other associates of the asexual generation of the crypt gall wasp, Bassettia pallida Ashmead. We compare the composition of this community to communities recently documented from two other cynipid gall wasps specializing on live oaks along the U.S. Gulf coast, Disholcaspis quercusvirens Ashmead and Belonocnema treatae Mayr. B. pallida and their galls support a diverse arthropod community, including over 25 parasitoids, inquilines, and other associated arthropods spanning 5 orders and 16 families. [ABSTRACT FROM AUTHOR]

Radially self-accelerating beams are rotating shape-invariant solutions of the Helmholtz equation. As such, they exhibit continuous indefinitely spiraling trajectories. Here we present the possibility to tailor those beams to achieve almost any desired beam cross section, without sacrificing the unique propagation characteristics. We discuss analytical tailoring opportunities and highlight their inherent limitations. Following that, by way of example, a genetic optimization algorithm is applied to demonstrate the feasibility of heuristic computer optimization methods in general. The convergence towards several test-targets is demonstrated and the influence of the chosen fitness function is discussed. [ABSTRACT FROM AUTHOR]

Mi'kmaq Elder Albert Marshall coined "Two-Eyed Seeing" in 2004, an Indigenous concept that emphasizes integrating the strengths of multiple perspectives to address complex challenges in ways that benefit all. In 2011, Two-Eyed Seeing became a policy of the Canadian Institutes of Health Research (CIHR)–Institute of Aboriginal Peoples' Health, as a part of its 5-year plan, and in 2012, CIHR funding was directed toward supporting efforts that apply the concept of Two-Eyed Seeing to research. However, little is known about how Two-Eyed Seeing has been operationalized in research. To address this ambiguity, a scoping review was conducted to map the key concepts involved when researchers intend to follow Two-Eyed Seeing guiding principles to study Indigenous health topics. Three research questions guided this scoping review: (1) What are the general characteristics (e.g., location of study, health topic studied) of primary research that has attempted to apply Two-Eyed Seeing when studying Indigenous health topics? (2) How did researchers operationalize the concept of Two-Eyed Seeing when they applied it to primary studies regarding Indigenous health topics? and (3) What process-related elements were present in Two-Eyed Seeing studies that accomplished their objectives? The results of this scoping review indicate there is an increasing trend in Two-Eyed Seeing–related peer-reviewed publications since its formal introduction by Mi'kmaq Elder Albert Marshall. The selected Two-Eyed Seeing–related projects were predominately conducted in Canada and published between 2011 and 2019. Projects predominately incorporated a community-based (participatory) research approach and qualitative/Indigenous methods, and six core process–related themes/elements were identified: (i) power was shared, (ii) culturally safe spaces were fostered, (iii) institutional and community ethics were followed, (iv) research projects were transformative, (v) rigor was maintained, and (vi) the structure of Western academia and traditional policy decision-making processes provided challenges for research teams and community partners, respectively. [ABSTRACT FROM AUTHOR]

Models for cluster randomized trials conducted over multiple time periods should account for underlying temporal trends. However, in practice there is often limited knowledge or data available to inform the choice of time parameterization of these trends, or to anticipate the implications of this choice on trial planning. In this article, we establish a sufficient condition for when the choice of time parameterization does not affect the form of the variance of the treatment effect estimator, thereby simplifying the planning of these trials. [ABSTRACT FROM AUTHOR]

Multiple-period cluster randomised trials, such as stepped wedge or cluster cross-over trials, are being conducted with increasing frequency. In the design and analysis of these trials, it is necessary to specify the form of the within-cluster correlation structure, and a common assumption is that the correlation between the outcomes of any pair of subjects within a cluster is identical. More complex models that allow for correlations within a cluster to decay over time have recently been suggested. However, most software packages cannot fit these models. As a result, practitioners may choose a simpler model. We analytically examine the impact of incorrectly omitting a decay in correlation on the variance of the treatment effect estimator and show that misspecification of the within-cluster correlation structure can lead to incorrect conclusions regarding estimated treatment effects for stepped wedge and cluster crossover trials. [ABSTRACT FROM AUTHOR]

Background: The Interrupted Time Series (ITS) is a robust design for evaluating public health and policy interventions or exposures when randomisation may be infeasible. Several statistical methods are available for the analysis and meta-analysis of ITS studies. We sought to empirically compare available methods when applied to real-world ITS data. Methods: We sourced ITS data from published meta-analyses to create an online data repository. Each dataset was re-analysed using two ITS estimation methods. The level- and slope-change effect estimates (and standard errors) were calculated and combined using fixed-effect and four random-effects meta-analysis methods. We examined differences in meta-analytic level- and slope-change estimates, their 95% confidence intervals, p-values, and estimates of heterogeneity across the statistical methods. Results: Of 40 eligible meta-analyses, data from 17 meta-analyses including 282 ITS studies were obtained (predominantly investigating the effects of public health interruptions (88%)) and analysed. We found that on average, the meta-analytic effect estimates, their standard errors and between-study variances were not sensitive to meta-analysis method choice, irrespective of the ITS analysis method. However, across ITS analysis methods, for any given meta-analysis, there could be small to moderate differences in meta-analytic effect estimates, and important differences in the meta-analytic standard errors. Furthermore, the confidence interval widths and p-values for the meta-analytic effect estimates varied depending on the choice of confidence interval method and ITS analysis method. Conclusions: Our empirical study showed that meta-analysis effect estimates, their standard errors, confidence interval widths and p-values can be affected by statistical method choice. These differences may importantly impact interpretations and conclusions of a meta-analysis and suggest that the statistical methods are not interchangeable in practice. [ABSTRACT FROM AUTHOR]

The similarities between quantum mechanics and paraxial optics were already well-known to the founding fathers of quantum mechanics; indeed knowledge of paraxial optics partly informed quantum mechanics as a wave theory. Likewise quantum mechanical methods have been employed to better understand optics, for example, to determine which optical transformations are in principle realisable and which not. Recently the notion of classical entanglement has been mooted, ushering in a new avenue to explore, perhaps bridging the classical-quantum divide. These developments have raised questions as to which quantum tasks could be implemented with classical light, taking advantage of the wealth of four centuries of experience in optics. In this article we review the similarities as well as differences between optics and quantum mechanics, providing a quantum notation for classical light. We review the evidence for cross-fertilisation between quantum mechanics and classical optics, in particular considering the issue of classical entanglement and its exploitation for quantum tasks. Our work provides a concise theoretical framework punctuated with relevant examples, and critically assesses the current state of the field and its limits. [ABSTRACT FROM AUTHOR]

Summary: Stepped wedge and other multiple‐period cluster randomized trials, which collect data from multiple clusters across multiple time periods, are being conducted with increasing frequency; statistical research into these designs has not kept apace. In particular, some stepped wedge designs with missing cluster–period "cells" have been proposed without any formal justification. Indeed there are no general guidelines regarding which cells of a stepped wedge design contribute the least information toward estimation of the treatment effect, and correspondingly which may be preferentially omitted. In this article, we define a metric of the information content of cluster–period cells, entire treatment sequences, and entire periods of the standard stepped wedge design as the increase in variance of the estimator of the treatment effect when that cell, sequence, or period is omitted. We show that the most information‐rich cells are those that occur immediately before or after treatment switches, but also that there are additional cells that contribute almost as much to the estimation of the treatment effect. However, the information content patterns depend on the assumed correlation structure for the repeated measurements within a cluster. [ABSTRACT FROM AUTHOR]

The cluster randomized crossover design has been proposed to improve efficiency over the traditional parallel cluster randomized design, which often involves a limited number of clusters. In recent years, the cluster randomized crossover design has been increasingly used to evaluate the effectiveness of health care policy or programs, and the interest often lies in quantifying the population-averaged intervention effect. In this paper, we consider the two-treatment two-period crossover design, and develop sample size procedures for continuous and binary outcomes corresponding to a population-averaged model estimated by generalized estimating equations, accounting for both within-period and interperiod correlations. In particular, we show that the required sample size depends on the correlation parameters through an eigenvalue of the within-cluster correlation matrix for continuous outcomes and through two distinct eigenvalues of the correlation matrix for binary outcomes. We demonstrate that the empirical power corresponds well with the predicted power by the proposed formulae for as few as eight clusters, when outcomes are analyzed using the matrix-adjusted estimating equations for the correlation parameters concurrently with a suitable bias-corrected sandwich variance estimator. [ABSTRACT FROM AUTHOR]

There has been a rapid expansion in the range of the rumen fluke species Calicophoron daubneyi over the last decade in the UK and Ireland, preceded by a similar increase in France from 1990. The reasons for this are unclear, but this species of rumen fluke utilises the mud snail, Galba truncatula, as its intermediate host, in contrast to other paramphistomes, for which aquatic snails are the commonest intermediate hosts. G. truncatula has a cosmopolitan distribution in temperate regions, and is also an intermediate host for Fasciola hepatica. Paramphistomosis has two manifestations in domestic ruminants: 1) a potentially fatal, acute disease with sudden onset of watery diarrhoea and weight loss that results from extensive pathology in the duodenum, where the juvenile flukes develop; and 2) colonisation of the rumen by adult flukes, without apparent detrimental effects on the host. Rumen fluke infections can be diagnosed through faecal samples, examined for either eggs or immature fluke or both. Oxyclozanide is the only available anthelmintic that is effective against both adult and immature rumen fluke. While prompt treatment of acute larval paramphistomosis is essential, the rationale for treating adult rumen fluke infections is less clear. [ABSTRACT FROM AUTHOR]

Interrupted time series (ITS) are often meta‐analysed to inform public health and policy decisions but examination of the statistical methods for ITS analysis and meta‐analysis in this context is limited. We simulated meta‐analyses of ITS studies with continuous outcome data, analysed the studies using segmented linear regression with two estimation methods [ordinary least squares (OLS) and restricted maximum likelihood (REML)], and meta‐analysed the immediate level‐ and slope‐change effect estimates using fixed‐effect and (multiple) random‐effects meta‐analysis methods. Simulation design parameters included varying series length; magnitude of lag‐1 autocorrelation; magnitude of level‐ and slope‐changes; number of included studies; and, effect size heterogeneity. All meta‐analysis methods yielded unbiased estimates of the interruption effects. All random effects meta‐analysis methods yielded coverage close to the nominal level, irrespective of the ITS analysis method used and other design parameters. However, heterogeneity was frequently overestimated in scenarios where the ITS study standard errors were underestimated, which occurred for short series or when the ITS analysis method did not appropriately account for autocorrelation. The performance of meta‐analysis methods depends on the design and analysis of the included ITS studies. Although all random effects methods performed well in terms of coverage, irrespective of the ITS analysis method, we recommend the use of effect estimates calculated from ITS methods that adjust for autocorrelation when possible. Doing so will likely to lead to more accurate estimates of the heterogeneity variance. [ABSTRACT FROM AUTHOR]

Background: The utilisation of massed therapy for treating posttraumatic stress disorder (PTSD) is gaining strength, especially prolonged exposure. However, it is unknown whether massed prolonged exposure (MPE) is non-inferior to standard prolonged exposure (SPE) protocols in the long term. The current study aimed to assess whether MPE was non-inferior to SPE at 12 months post-treatment, and to ascertain changes in secondary measure outcomes. Methods: A multi-site non-inferiority randomised controlled trial (RCT) compared SPE with MPE in 12 clinics. The primary outcome was PTSD symptom severity (CAPS-5) at 12 months post-treatment commencement. Secondary outcome measures included symptoms of depression, anxiety, anger, disability, and quality of life at 12 weeks and 12 months post-treatment commencement. Outcome assessors were blinded to treatment allocation. The intention-to-treat sample included 138 Australian military members and veterans and data were analysed for 134 participants (SPE = 71, MPE = 63). Results: Reductions in PTSD severity were maintained at 12 months and MPE remained non-inferior to SPE. Both treatment groups experienced a reduction in depression, anxiety, anger, and improvements in quality of life at 12 weeks and 12 months post-treatment commencement. Treatment effects for self-reported disability in the SPE group at 12 weeks were not maintained, with neither group registering significant effects at 12 months. Conclusions: The emergence of massed protocols for PTSD is an important advancement. The current study provides RCT evidence for the longevity of MPE treatment gains at 12 months post-treatment commencement and demonstrated non-inferiority to SPE. Promisingly, both treatments also significantly reduced the severity of comorbid symptoms commonly occurring alongside PTSD. [ABSTRACT FROM AUTHOR]

The article discusses the approach to overcome the weak chiral light-matter interaction is to create artificial materials made from called metaatoms. Topics include the chiral interaction of light and matter is typically very weak and thus requires the use of bulky materials; BIC refers to a state in which light of a certain frequency is trapped bouncing around, and the evident chiral asymmetry found in amino acids.

Treatment options for clinical parasitic bronchitis (PB) are largely based on anthelmintics, with supportive therapy including non-steroidal anti-inflammatories (NSAIDs) and antibiotics, when indicated. Macrocyclic lactones (MLs), benzimidazoles and levamisole are all effective against adult and larval lungworms, so the choice of product depends on other criteria, including duration of action and ease of administration, which can be important in dyspnoeic animals. Control of PB in youngstock can be accomplished through the use of anthelmintics in early-season strategies designed to limit pasture Dictyocaulus viviparus larval populations, but are not easy to implement in herds other than on autumn-calving dairy farms. Likewise, though vaccination provides predictable control of PB in youngstock, it is best suited to calves from autumn calving herds, however, it can also be used pre-turnout as a ‘booster’ in previously exposed, older cattle. Grazing management has a limited role to play in the control of PB both because of unreliability and because some of the recommendations run counter to recommended grassland management practices. Veterinary clinicians need to familiarise themselves with all possible options and outcomes for the control of PB and tailor their recommendations to the individual farm and farmer. [ABSTRACT FROM AUTHOR]

Declines in pollinators, particularly wild bees, along with rising demands for their services has intensified efforts to examine bee communities in different types of habitats. In this study we use a phylogenetic approach to compare and contrast bee communities associated with six small produce farms, eight large prairies, and five naturally small hill prairies in Iowa. We compare the mean phylogenetic distance (MPD) and the mean nearest taxon distance (MNTD) of bees in each community to expected mean MPD and MNTD values generated from 1000 random permutations of a tree composed of 144 species found across all sites. Standardized effect size scores for MPD using presence-absence data showed significant clustering of bee communities at five of six farms and two of the five hill prairies. Clustering at the farms and hill prairies was due primarily to the significantly lower number of species in the Andrenidae (0–5 species per site), especially species of Andrena , as well as significantly greater number of species in the Halictidae (9–22 species/site), particularly Lasioglossum ( Dialictus ). Lack of Andrenidae spp. may be related to a lack of appropriate floral resources, indicating that enriched prairie plantings for pollinators at farms could enhance the abundance of Andrena species and hence pollinator services at these sites. The higher richness of the ground-nesting Lasioglossum likely results from soil disturbance regimes at produce farms and the naturally shallow, rocky soil with exposed surface at hill prairies, respectively. Analyses of MNTD using either abundance weighted or presence-absence data and analyses of MPD using abundance data did not indicate consistent differences between the three site types, but do point to important differences between sites in phylogenetic composition of bee communities. Our results show that phylogenetic analyses of wild bee community diversity may be a useful tool for measuring how bee communities differ in composition as a result of natural variation and human-related changes in landscapes. [ABSTRACT FROM AUTHOR]

The bovine lungworm, Dictyocaulus viviparus, causes disease in all ages of cattle and in addition to having a selfevident effect on animal welfare, it can have a considerable economic impact at farm level, even with subclinical infections. While most clinical cases are seen in cattle at pasture from July until housing, occasional outbreaks occur in housed cattle that have been infected previously at grass, or occasionally from infections acquired from forage or low-level cycling in straw yards. While the overall seasonal pattern of infection is consistent over large temporal and spatial scales, there is marked year-to-year and within season variability in the number of cases seen at both regional and farm levels. This relative unpredictability can bring uncertainty to decisions on control. In order to be able to provide sound, evidence-based advice on treatment and control to farmers, it is important that clinicians grasp important, practically relevant aspects of lungworm biology, pathology, immunity and epidemiology: the aim of this article is to do just that. A second article describes and analyses the options for prevention and treatment of husk, based on this knowledge. [ABSTRACT FROM AUTHOR]

Background: Fasciola hepatica is a helminth parasite of global importance in livestock, with major economic impact. However information on F. hepatica infections in Irish pasture-based dairy herds is limited. Therefore this study was conducted in order to determine the prevalence, seasonality and management factors associated with F. hepatica. A total of 319 Irish dairy herds were selected for this study. Bulk tank milk (BTM) samples were collected from 290 dairy farms on a quarter year basis, while from a further 29 dairy farms BTM samples were collected on a monthly basis to provide a more detailed pattern of F. hepatica exposure in Irish herds. BTM samples were analysed using a commercially available F. hepatica antibody detection ELISA. Furthermore, within-herd prevalence of F. hepatica was assessed in a subset of these 29 herds (n = 17); both individual serum samples and bulk tank milk samples were collected. Results: A within-herd prevalence of ≤ 50 % was found for herds with negative bulk tank milk samples. The mean prevalence of the 290 study herds was 75.4 % (Range 52 %-75.1 %), with the highest prevalence being observed in November (75.1 %). The seasonal pattern of F. hepatica shows elevated antibodies as the grazing season progressed, reaching a peak in January. A significant association was found between F. hepatica and age at first calving. Conclusion: This study demonstrates that F. hepatica is present in a large proportion of Irish dairy herds and provides a basis on which control practices, particularly in adult dairy cows, can be reviewed. [ABSTRACT FROM AUTHOR]

The cellular mechanisms of meiosis are critical for proper gamete formation in sexual organisms. Functional studies in model organisms have identified genes essential for meiosis, yet the extent to which this core meiotic machinery is conserved across non-model systems is not fully understood. Moreover, it is unclear whether deviation from canonical modes of sexual reproduction is accompanied by modifications in the genetic components involved in meiosis. We used a robust approach to identify and catalogue meiosis genes in Hymenoptera, an insect order typically characterized by haplodiploid reproduction. Using newly available genome data, we searched for 43 genes involved in meiosis in 18 diverse hymenopterans. Seven of eight genes with roles specific to meiosis were found across a majority of surveyed species, suggesting the preservation of core meiotic machinery in haplodiploid hymenopterans. Phylogenomic analyses of the inventory of meiosis genes and the identification of shared gene duplications and losses provided support for the grouping of species within Proctotrupomorpha, Ichneumonomorpha, and Aculeata clades, along with a paraphyletic Symphyta. The conservation of meiosis genes across Hymenoptera provides a framework for studying transitions between reproductive modes in this insect group. [ABSTRACT FROM AUTHOR]

The trematode, Fasciola hepatica, is a cosmopolitan parasite of temperate regions that can infect a wide variety of wild and domestic mammalian species, including man. Host-responses differ amongst different species and this article focuses on the contrast between cattle and sheep, the two classes of livestock in which fasciolosis assumes the greatest economic importance. In the sheep, acute fasciolosis resulting from parenchymal damage to the liver and haemorrhage caused by migrating juvenile flukes is a severe and potentially fatal disease. In contrast, the parenchymal stages have limited effects in cattle and the acute form of the disease is extremely rare. Though there is no evidence for a functional, acquired immune response to Fasciola hepatica, cattle provide a less hospitable environment, probably due to the profound changes in parasitised bile ducts, which render them as unsuitable habitats for feeding fluke. Consequently, in untreated cattle, many liver fluke die within 18 months of infection, though some can survive for 2 years or more. In the sheep, essentially, the fluke can live as long as the sheep; up to 11 years has been reported. These differences lead to the need for different treatment approaches in cattle and sheep with respect to juvenile fluke, but do also provide some opportunities for novel control approaches, based on the relative tolerance of cattle and their ability to limit parasitic damage to the liver parenchyma. [ABSTRACT FROM AUTHOR]

Abattoir surveys and findings from post-mortem meat inspection are commonly used to estimate infection or disease prevalence in farm animal populations. However, the function of an abattoir is to slaughter animals for human consumption, and the collection of information on animal health for research purposes is a secondary objective. This can result in methodological shortcomings leading to biased prevalence estimates. Selection bias can occur when the study population as obtained from the abattoir is not an accurate representation of the target population. Virtually all of the tests used in abattoir surveys to detect infections or diseases that impact animal health are imperfect, leading to errors in identifying the outcome of interest and consequently, information bias. Examination of abattoir surveys estimating prevalence in the literature reveals shortcomings in the methods used in these studies. While the STROBE-Vet statement provides clear guidance on the reporting of observational research, we have not found any guidelines in the literature advising researchers on how to conduct abattoir surveys. This paper presents a protocol in two flowcharts to help researchers (regardless of their background in epidemiology) to first identify, and, where possible, minimise biases in abattoir surveys estimating prevalence. Flowchart 1 examines the identification of the target population and the appropriate study population while Flowchart 2 guides the researcher in identifying, and, where possible, correcting potential sources of outcome misclassification. Examples of simple sensitivity analyses are also presented which approximate the likely uncertainty in prevalence estimates due to systematic errors. Finally, the researcher is directed to outline any limitations of the study in the discussion section of the paper. This protocol makes it easier to conduct an abattoir survey using sound methods, identifying and, where possible, minimizing biases. [ABSTRACT FROM AUTHOR]

Background: Standard stepped wedge trials, where clusters switch from the control to the intervention condition in a staggered manner, can be costly and burdensome. Recent work has shown that the amount of information contributed by each cluster in each period differs, with some cluster-periods contributing a relatively small amount of information. We investigate the patterns of the information content of cluster-period cells upon iterative removal of low-information cells, assuming a model for continuous outcomes with constant cluster-period size, categorical time period effects, and exchangeable and discrete-time decay intracluster correlation structures. Methods: We sequentially remove pairs of "centrosymmetric" cluster-period cells from an initially complete stepped wedge design which contribute the least amount of information to the estimation of the treatment effect. At each iteration, we update the information content of the remaining cells, determine the pair of cells with the lowest information content, and repeat this process until the treatment effect cannot be estimated. Results: We demonstrate that as more cells are removed, more information is concentrated in the cells near the time of the treatment switch, and in "hot-spots" in the corners of the design. For the exchangeable correlation structure, removing the cells from these hot-spots leads to a marked reduction in study precision and power, however the impact of this is lessened for the discrete-time decay structure. Conclusions: Removing cluster-period cells distant from the time of the treatment switch may not lead to large reductions in precision or power, implying that certain incomplete designs may be almost as powerful as complete designs. [ABSTRACT FROM AUTHOR]

Background: A short, effective therapy for posttraumatic stress disorder (PTSD) could decrease barriers to implementation and uptake, reduce dropout, and ameliorate distressing symptoms in military personnel and veterans. This non-inferiority RCT evaluated the efficacy of 2-week massed prolonged exposure (MPE) therapy compared to standard 10-week prolonged exposure (SPE), the current gold standard treatment, in reducing PTSD severity in both active serving and veterans in a real-world health service system. Methods: This single-blinded multi-site non-inferiority RCT took place in 12 health clinics across Australia. The primary outcome was PTSD symptom severity measured by the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5) at 12 weeks. 138 military personnel and veterans with PTSD were randomised. 71 participants were allocated to SPE, with 63 allocated to MPE. Results: The intention-to-treat sample included 138 participants, data were analysed for 134 participants (88.1% male, M = 46 years). The difference between the mean MPE and SPE group PTSD scores from baseline to 12 weeks-post therapy was 0.94 [95% confidence interval (CI) −4.19 to +6.07]. The upper endpoint of the 95% CI was below +7, indicating MPE was non-inferior to SPE. Significant rates of loss of PTSD diagnosis were found for both groups (MPE 53.8%, SPE 54.1%). Dropout rates were 4.8% (MPE) and 16.9% (SPE). Conclusions: MPE was non-inferior to SPE in significantly reducing symptoms of PTSD. Significant reductions in symptom severity, low dropout rates, and loss of diagnosis indicate MPE is a feasible, accessible, and effective treatment. Findings demonstrate novel methods to deliver gold-standard treatments for PTSD should be routinely considered. [ABSTRACT FROM AUTHOR]

Faecal egg counts (FECs) are commonly promulgated as a means of determining the status and impact of parasitic gastroenteritis (PGE) in cattle, yet there is little scientific evidence for consistent, quantitative associations between FECs, worm burdens or the effects of PGE on the hosts. Examples are provided of applications of FEC in cattle that do have an evidence base and also of alternative aids to anthelmintic treatment decisions, such as growth rates in young cattle. The potential value of FECs in veterinary/farmer interactions is also addressed as is the need to justify diagnostics through demonstration of favourable cost-benefit ratios. [ABSTRACT FROM AUTHOR]

The notion that shifts to new hosts can initiate insect speciation is more than 150 years old, yet widespread conflation with paradigms of sympatric speciation has led to confusion about how much support exists for this hypothesis. Here, we review 85 insect systems and evaluate the relationship between host shifting, reproductive isolation, and speciation. We sort insects into five categories: (1) systems in which a host shift has initiated speciation; (2) systems in which a host shift has made a contribution to speciation; (3) systems in which a host shift has caused the evolution of new reproductive isolating barriers; (4) systems with host-associated genetic differences; and (5) systems with no evidence of host-associated genetic differences. We find host-associated genetic structure in 65 systems, 43 of which show that host shifts have resulted in the evolution of new reproductive barriers. Twenty-six of the latter also support a role for host shifts in speciation, including eight studies that definitively support the hypothesis that a host shift has initiated speciation. While this review is agnostic as to the fraction of all insect speciation events to which host shifts have contributed, it clarifies that host shifts absolutely can and do initiate speciation. [ABSTRACT FROM AUTHOR]

Most species of gastrointestinal and pulmonary parasitic nematodes of cattle and sheep are host specific and farmers with mixed livestock farms can take advantage of this aspect of parasite biology to mitigate and control pasture-associated parasite infections through mixed or co-grazing. However, some common parasites, such as liver and rumen fluke, are generalists and can parasitise a wide range of mammalian hosts, nevertheless, differences in host responses have the potential to be used to manage high-risk fields, without compromising health or performance. Current research is exploring the possible role of bioactive plants in the control of parasites. [ABSTRACT FROM AUTHOR]

Optical modes that carry orbital angular momentum (OAM) are routinely produced external to the laser cavity and have found a variety of applications, thus increasing the demand for integrated solutions for their production. Yet such modes are notoriously difficult to produce from lasers due to the strict symmetry requirements for their creation, together with the need to break the degeneracy in helicity. Here, we review the progress made since 1992 in producing such twisted light modes directly at the source, from gas to solid-state lasers, bulk to integrated on-chip solutions, through to generic devices for on-demand OAM in both scalar and vector forms. This article is part of the themed issue 'Optical orbital angular momentum'. [ABSTRACT FROM AUTHOR]

Objective: To compare health service utilization and disability claims among military personnel with multisymptom illness (MSI) (but no chronic diseases), those with chronic disease(s) and those without MSI or chronic diseases. MSI is also known as Gulf War illness.Design: Cohort study.Setting: Australia.Participants: In total, 1288 participants of a Gulf War veterans' study conducted in 2000-2003 (Wave-1) were followed up in 2011-2012 (Wave-2), aged on average 40 years. About 160 had MSI, 217 had chronic disease(s) and 911 had neither chronic disease(s) nor MSI.Methods: At Wave-2, the cohort was linked to the national Medicare and Department of Veterans' Affairs (DVA) databases to obtain health service utilization and disability claims data recorded between 2001 and 2012.Results: The likelihood of visiting a general practitioner (GP) (risk ratio [RR] = 1.04, 95% confidence interval [CI] = 0.92, 1.19) or visiting a specialist medical doctor (RR = 0.83; 95% CI = 0.54, 1.28) or hospitalizations (RR = 0.89; 95% CI = 0.61, 1.29) or) in the 12 months preceding Wave-2 or successfully claiming for DVA disability compensation (RR = 1.13; 95% CI = 0.86, 1.47) was similar for personnel with MSI and those with chronic disease(s). However, GP consultations, hospitalizations, specialist doctor consultations and disability claims were significantly higher among those with MSI than those without MSI/chronic diseases.Conclusions: Health service use and disability claims by personnel with MSI were comparable to those with chronic disease(s), but were in excess of those without MSI/chronic diseases. Hence recognition of the high health service use by personnel with MSI is important to ensure adequate provision of health services. [ABSTRACT FROM AUTHOR]

In cluster randomised cross-over (CRXO) trials, clusters receive multiple treatments in a randomised sequence over time. In such trials, there is usual correlation between patients in the same cluster. In addition, within a cluster, patients in the same period may be more similar to each other than to patients in other periods. We demonstrate that it is necessary to account for these correlations in the analysis to obtain correct Type I error rates. We then use simulation to compare different methods of analysing a binary outcome from a two-period CRXO design. Our simulations demonstrated that hierarchical models without random effects for period-within-cluster, which do not account for any extra within-period correlation, performed poorly with greatly inflated Type I errors in many scenarios. In scenarios where extra within-period correlation was present, a hierarchical model with random effects for cluster and period-within-cluster only had correct Type I errors when there were large numbers of clusters; with small numbers of clusters, the error rate was inflated. We also found that generalised estimating equations did not give correct error rates in any scenarios considered. An unweighted cluster-level summary regression performed best overall, maintaining an error rate close to 5% for all scenarios, although it lost power when extra within-period correlation was present, especially for small numbers of clusters. Results from our simulation study show that it is important to model both levels of clustering in CRXO trials, and that any extra within-period correlation should be accounted for. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Farmers manage their pastures and grazing animals primarily to ensure that swards provide adequate, quality nutrients to support animal performance, but it is also possible to provide useful levels of parasite control without compromising production. On cattle only farms the easiest options for the control of parasitic gastroenteritis in young cattle revolve around the avoidance of high risk pastures from July onwards. On many farms, silage/hay aftermaths that have not been grazed by cattle for 12 months or more can provide low risk fields on which cattle can thrive with minimal reliance on anthelmintics. [ABSTRACT FROM AUTHOR]

Background: The cluster randomised crossover (CRXO) design is gaining popularity in trial settings where individual randomisation or parallel group cluster randomisation is not feasible or practical. Our aim is to stimulate discussion on the content of a reporting guideline for CRXO trials and to assess the reporting quality of published CRXO trials. Methods: We undertook a systematic review of CRXO trials. Searches of MEDLINE, EMBASE, and CINAHL Plus as well as citation searches of CRXO methodological articles were conducted to December 2014. Reporting quality was assessed against both modified items from 2010 CONSORT and 2012 cluster trials extension and other proposed quality measures. Results: Of the 3425 records identified through database searching, 83 trials met the inclusion criteria. Trials were infrequently identified as "cluster randomis(z)ed crossover" in title (n = 7, 8%) or abstract (n = 21, 25%), and a rationale for the design was infrequently provided (n = 20, 24%). Design parameters such as the number of clusters and number of periods were well reported. Discussion of carryover took place in only 17 trials (20%). Sample size methods were only reported in 58% (n = 48) of trials. A range of approaches were used to report baseline characteristics. The analysis method was not adequately reported in 23% (n = 19) of trials. The observed within-cluster within-period intracluster correlation and within-cluster between-period intracluster correlation for the primary outcome data were not reported in any trial. The potential for selection, performance, and detection bias could be evaluated in 30%, 81%, and 70% of trials, respectively. Conclusions: There is a clear need to improve the quality of reporting in CRXO trials. Given the unique features of a CRXO trial, it is important to develop a CONSORT extension. Consensus amongst trialists on the content of such a guideline is essential. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to conduct a systematic review and meta-analysis of multisymptom illness (MSI) in 1990 to 1991 Gulf/Afghanistan/Iraq War veterans. Methods: Electronic databases were searched from January 1990, June 2014 for studies on MSI prevalence in Gulf/ Afghanistan/Iraq War veterans, based on the Centers for Disease Control and Prevention MSI case definition, and which included a military comparison group. Results: Seven studies were identified among US, UK, and Australian Gulf War veterans; no studies were identified in Afghanistan/Iraq War veterans. MSI prevalence in Gulf War veterans and comparison groups ranged from 26 to 65% and from 12 to 37%, respectively. More recent studies were larger, with improved designs. The pooled odds ratio comparing Gulf War veterans to other military groups was 2.74 (95% confidence interval 2.15 to 3.51). Conclusion: The systematic review showed that MSI was most prevalent in Gulf War veterans, emphasizing the health burden of MSI in this veteran population. [ABSTRACT FROM AUTHOR]