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Background: The identification of people at risk of cognitive impairment is essential for improving recruitment in secondary prevention trials of Alzheimer's disease. We aimed to test and qualify a biomarker risk assignment algorithm (BRAA) to identify participants at risk of developing mild cognitive impairment due to Alzheimer's disease within 5 years, and to evaluate the safety and efficacy of low-dose pioglitazone to delay onset of mild cognitive impairment in these at-risk participants. Methods: In this phase 3, multicentre, randomised, double-blind, placebo-controlled, parallel-group study, we enrolled cognitively healthy, community living participants aged 65–83 years from 57 academic affiliated and private research clinics in Australia, Germany, Switzerland, the UK, and the USA. By use of the BRAA, participants were grouped as high risk or low risk. Participants at high risk were randomly assigned 1:1 to receive oral pioglitazone (0·8 mg/day sustained release) or placebo, and all low-risk participants received placebo. Study investigators, site staff, sponsor personnel, and study participants were masked to genotype, risk assignment, and treatment assignment. The planned study duration was the time to accumulate 202 events of mild cognitive impairment due to Alzheimer's disease in White participants who were at high risk (the population on whom the genetic analyses that informed the BRAA development was done). Primary endpoints were time-to-event comparisons between participants at high risk and low risk given placebo (for the BRAA objective), and between participants at high risk given pioglitazone or placebo (for the efficacy objective). The primary analysis included all participants who were randomly assigned, received at least one dose of study drug, and had at least one valid post-baseline visit, with significance set at p=0·01. The safety analysis included all participants who were randomly assigned and received at least one dose of study medication. An efficacy futility analysis was planned for when approximately 33% of the anticipated events occurred in the high-risk, White, non-Hispanic or Latino group. This trial is registered with ClinicalTrials.gov, NCT01931566. Findings: Between Aug 28, 2013, and Dec 21, 2015, we enrolled 3494 participants (3061 at high risk and 433 at low risk). Of those participants, 1545 were randomly assigned to pioglitazone and 1516 to placebo. 1104 participants discontinued treatment (464 assigned to the pioglitazone group, 501 in the placebo high risk group, and 139 in the placebo low risk group). 3399 participants had at least one dose of study drug or placebo and at least one post-baseline follow-up visit, and were included in the efficacy analysis. 3465 participants were included in the safety analysis (1531 assigned to the pioglitazone group, 1507 in the placebo high risk group, and 427 in the placebo low risk group). In the full analysis set, 46 (3·3%) of 1406 participants at high risk given placebo had mild cognitive impairment due to Alzheimer's disease, versus four (1·0%) of 402 participants at low risk given placebo (hazard ratio 3·26, 99% CI 0·85–12·45; p=0·023). 39 (2·7%) of 1430 participants at high risk given pioglitazone had mild cognitive impairment, versus 46 (3·3%) of 1406 participants at high risk given placebo (hazard ratio 0·80, 99% CI 0·45–1·40; p=0·307). In the safety analysis set, seven (0·5%) of 1531 participants at high risk given pioglitazone died versus 21 (1·4%) of 1507 participants at high risk given placebo. There were no other notable differences in adverse events between groups. The study was terminated in January, 2018, after failing to meet the non-futility threshold. Interpretation: Pioglitazone did not delay the onset of mild cognitive impairment. The biomarker algorithm demonstrated a 3 times enrichment of events in the high risk placebo group compared with the low risk placebo group, but did not reach the pre-specified significance threshold. Because we did not complete the study as planned, findings can only be considered exploratory. The conduct of this study could prove useful to future clinical development strategies for Alzheimer's disease prevention studies. Funding: Takeda and Zinfandel.

Functional neurological disorder (FND) is a common and disabling disorder that is often considered difficult to treat, particularly in adults. Psychological therapies are often recommended for FND. Outcome research on psychological therapies for FND has grown in recent years but has not been systematically evaluated since 2005. This study aims to build on that by systematically reviewing the evidence-base for individual outpatient cognitive behavioural and psychodynamic psychotherapies for FND. Medical databases were systematically searched for prospective studies of individual outpatient psychotherapy for FND with at least five adult participants. Studies were assessed for methodological quality using a standardised assessment tool. Results were synthesised, and effect sizes calculated for illustrative purposes. The search strategy identified 131 relevant studies, of which 19 were eligible for inclusion: 12 examining cognitive behavioural therapy (CBT) and 7 investigating psychodynamic therapy (PDT). Eleven were pre–post studies and eight were randomised controlled trials. Most studies recruited a single symptom-based subtype rather than all presentations of FND. Effect sizes, where calculable, showed generally medium-sized benefits for physical symptoms, mental health, well-being, function and resource use for both CBT and PDT. Outcomes were broadly comparable across the two therapy types, although a lack of high-quality controlled trials of PDT is a significant limitation, as is the lack of long-term follow-up data in the majority of identified CBT trials. In conclusion, both CBT and PDT appear to potentially offer some benefit for FND, although better quality studies are needed.

Volcanism on Earth and on other planets and satellites is dominated by the eruption of low viscosity magmas. During explosive eruption, high melt temperatures and the inherent low viscosity of the fluidal pyroclasts allow for substantial post-fragmentation modification during transport obscuring the record of primary, magmatic fragmentation processes. Here, we show these syn-eruption modifications, in the form of melt stripping and agglutination, to be advantageous for providing fundamental insights into lava fountain and jet dynamics, including eruption velocities, grain size distributions and melt physical properties. We show how enigmatic, complex pyroclasts termed pelletal lapilli form by a two-stage process operating above the magmatic fragmentation surface. Melt stripping from pyroclast surfaces creates a spray of fine melt droplets whilst sustained transport in the fountain allows for agglutination and droplet scavenging, thereby coarsening the grain size distribution. We conclude with a set of universal regime diagrams, applicable for all fluidal fountain products, that link fundamental physical processes to eruption conditions and melt physical properties.

Estimation of attenuation from positron emission tomography (PET) data only is of interest for hybrid PET-MR and systems where CT is not available or recommended. However, when using data from a single energy window, emission-based non-time-of-flight (TOF) PET attenuation correction (AC) methods suffer from “cross-talk” artifacts. Based on earlier work, this article explores the hypothesis that cross-talk can be reduced by using more than one energy window. We propose an algorithm for the simultaneous estimation of both activity and attenuation images, as well as, the scatter component of the measured data from a PET acquisition, using multiple energy windows. The model for the measurements is 3-D and accounts for the finite energy resolution of PET detectors; it is restricted to single scatter. The proposed energy-based simultaneous maximum likelihood reconstruction of activity and attenuation with photopeak scatter re-estimation algorithm is compared with simultaneous estimation from a single energy window simultaneous maximum likelihood reconstruction of activity and attenuation with photopeak scatter re-estimation. The evaluation is based on simulations using the characteristics of the Siemens mMR scanner. Phantoms of different complexity were investigated. In particular, a 3-D XCAT torso phantom was used to assess the inpainting of attenuation values within the lung region. Results show that the cross-talk present in non-TOF maximum likelihood reconstruction of activity and attenuation reconstructions is significantly reduced when using multiple energy windows and indicate that the proposed approach warrants further investigation.

Pyroclastic deposits of the Holocene Igwisi Hills kimberlite volcanoes, Tanzania, preserve unequivocal evidence for rapid, syn-eruptive agglutination. The unusual pyroclasts are composed of ash-sized particles agglutinated to each other by thin necks. The textures suggest the magma was disrupted into droplets during ascent. Collisions between particles occurred within a volcanic plume and on deposition within the conduit to form a weakly agglutinated, porous pyroclastic deposit. Theoretical considerations indicate that agglutination occurred over short timescales. Agglutinated clasts were entrained into weak volcanic plumes and deposited around the craters. Our results support the notion that agglutination can occur during kimberlite eruptions, and that some coherent, dense rocks in ancient kimberlite pipes interpreted as intrusive rocks could instead represent agglutinated pyroclastic rocks. Differentiating between agglutinated pyroclastic rocks and effusive or intrusive rocks in kimberlite pipes is important because of the potential effects that pyroclastic processes might have on diamond concentrations in deposits.

On-board emission testing data for two ocean-going vessels is used to assess the performance of a new Australian ship emissions model, and to also assess the impact of local currents on emission predictions. Prediction performance is only marginally affected by AIS post-processing method and inclusion of local current information. Model performance was assessed for three different aspects, fuel-based emission factors (g/g CO2), engine work-based emission factors (g/kWh) and distance-based emission factors (g/km). Analysis of fuel-based and engine-work based emission factors suggest good performance and small to reasonable mean prediction errors for CO2 (±10%), PM10 (±15%) and SO2 (±20%). For NOx and CO, on-board emissions testing suggest that model emission factors are biased high and low with mean prediction errors +60–70% and −60%, respectively. The results for distance-based emission factors were not considered to be meaningful due to spatial and temporal inaccuracies in linking on-board testing with the AIS data that could not be resolved. Given the importance of AIS data as input to fuel and emissions modelling, it is recommended that the spatial and temporal accuracy of AIS data is investigated and confirmed in future studies. Moreover, the differences found in this study between model predictions and on-board measurements highlight a few limitations in application of generic fleet-based models.

BVD is funded by the Natural Environment Research Council through the EnvEast Doctoral Training partnership (grant number NE/1002582/1)., Proximal deposits of small-volume trachytic eruptions are an under-studied record of eruption dynamics despite being common across a range of settings. The 59 ± 4 ka Echo Canyon deposits, Ascension Island, resulted from a small-volume explosiveeffusive trachytic eruption. Variations in juvenile clast texture reveal changes in ascent dynamics and transitions in eruption style. Five dominant textural types are identified within the pumice lapilli population. Early Strombolian-Vulcanian eruption phases are typified by macro- and micro-vesicular equant clast types. Sheared clasts are most abundant at the eruption peak, transitioning to dense clasts in later phases due to shear-induced coalescence, outgassing and vesicle collapse. Melt densification and outgassing via tuffisite veins increased plume density, contributing to partial column collapse and the explosive-effusive transition. Bulk vesicularity distributions indicate a shift in dominant fragmentation mechanism during the eruption, from early-stage bubble interference and rupture to late-stage transient fragmentation, with a transient peak of Plinian activity. Dome and lava groundmass crystallinities of up to 70% indicate near-complete degassing during effusive phases, followed by shallow over pressurisation and a final less explosive phase. We provide textural evidence for high-intensity explosive phases and rapid transitions in eruptive style during small-volume trachytic eruptions and consider the impact of trachytic melt compositions on underlying dynamics of these short-lived, explosive events. This analysis demonstrates the value of detailed stratigraphy in understanding critical changes in eruption dynamics and the timescales over which they may occur which is of particular value in anticipating future eruptions of this type., Natural Environment Research Council through the EnvEast Doctoral Training partnership NE/1002582/1

Diesel particulate filters (DPF) are widely adopted in diesel vehicles to meet the increasingly stringent emission regulations, which require continuous passive regenerations or/and periodic active regenerations to burn off the accumulated particulate matter (PM). In spite of many laboratory studies using DPF benches and engine/chassis dynamometers, there is currently a lack of investigation on DPF regeneration under real-world conditions. Therefore, this study was conducted to investigate the impact of active DPF regenerations on the fuel consumption and gaseous and particulate emissions performance of a diesel light goods vehicle under real-driving conditions by using the state-of-the-art portable emission measurement system. In total, 60 real-driving emission (RDE) tests (∼1200 km in total) were performed on the same route during the same periods of a day, to minimise the effect of uncontrollable real-world factors on the performance evaluation. The results showed that real-world active DPF regenerations occurred every 130 km for the studied vehicle. Although they did not occur frequently, DPF regenerations increased the trip-averaged fuel consumption rate by 13% on average. CO and THC emission factors tended to increase with DPF regenerations because the post combustion used to achieve the high exhaust temperature for regeneration of the filter occurred under oxygen-lean conditions. Total NOx emissions were not affected but NO2/NOx ratio was greatly reduced by DPF regeneration due to lower NO oxidation by the diesel oxidation catalyst and higher NO2 reduction by the DPF. Finally, DPF regenerations sharply increased PM emission factors by 27 times compared with a trip without DPF regeneration, resulting in significant exceedance of the emission limit.

Volcanism on Earth and on other planets and satellites is dominated by the eruption of low viscosity magmas. During explosive eruption, high melt temperatures and the inherent low viscosity of the fluidal pyroclasts allow for substantial post-fragmentation modification during transport obscuring the record of primary, magmatic fragmentation processes. Here, we show these syn-eruption modifications, in the form of melt stripping and agglutination, to be advantageous for providing fundamental insights into lava fountain and jet dynamics, including eruption velocities, grain size distributions and melt physical properties. We show how enigmatic, complex pyroclasts termed pelletal lapilli form by a two-stage process operating above the magmatic fragmentation surface. Melt stripping from pyroclast surfaces creates a spray of fine melt droplets whilst sustained transport in the fountain allows for agglutination and droplet scavenging, thereby coarsening the grain size distribution. We conclude with a set of universal regime diagrams, applicable for all fluidal fountain products, that link fundamental physical processes to eruption conditions and melt physical properties.

PurposeAssessment of psychotherapeutic competence is increasingly regarded as important in the delivery of psychological services and training programmes. This article reviews tools designed to assess clinical competence in psychodynamic, interpersonal, and relational models of therapy.MethodsPsycINFO, CINAHL, and Web of Science online databases were reviewed using terms relating to competence, psychotherapy, and measurement. Titles and abstracts of all articles were screened, and full texts of remaining articles were read. Reference lists of included articles were also screened. Papers that described a measure of psychotherapeutic competence in a psychodynamic, interpersonal, or relational model, and reported at least one assessment of the reliability and/or validity of the measure, were included. The quality of the studies was evaluated, and the quality of individual measures was summarized.ResultsFourteen studies met the inclusion criteria, examining 13 competence measures for 12 specific models of therapy. Competence measures were not found for several NICE‐recommended models of therapy. Some measures demonstrated strengths in certain areas of reliability and validity; however, there were a number of quality issues in development and psychometric properties that suggest none of the measures are currently proven for widespread use.ConclusionsFurther research is required to refine currently existing measures and develop new measures for key NICE‐recommended models of therapy.Practitioner pointsAssessment and improvement of therapist competence is key to provision of high‐quality psychotherapeutic interventions.This review shows there are few measures of competence in relational therapy models and several NICE‐recommended models do not have corresponding competence measures.Measures that do exist are mixed in terms of their validity and reliability and should therefore be used with caution.

Surrogate fuels for hydrothermal liquefaction (HTL) algae biocrude depicting its nitrogen (N) and sulphur (S) content were simulated in this study and tested in a multi-cylinder diesel engine. The influence of N and S presence in the fuel on its combustion behaviour and emissions profile was investigated. To our knowledge, N and S-containing fuels in reference to HTL algae biocrude, have not been reported in an internal combustion engine in the literature, which is the unique and novelty of the current work. The presence of N and S in the fuel affected its physical properties. The density of the surrogate fuel was slightly higher than that of diesel, while viscosity, in general, was maintained. The flash point of the N and S-fuel was reduced in the presence of N. N had a stronger effect than S in reducing the lower heating value (LHV) of the surrogate fuel than that of diesel. Compared to diesel, emissions of both carbon monoxide (CO) and unburned hydrocarbons (HC) were lower for N and S-containing fuels. Increasing nitrogen oxides (NOx) and sulphur dioxide (SO2) emissions were observed with increasing N and S content, respectively, in the fuels. A significant increase in particle mass (PM) emissions was observed at high concentrations of N (4.5 wt%) and S (0.2–0.4 wt%). Such values of S are found in some off-road and marine applications. Therefore, HTL biofuel can be a low-sulphur alternative fuel for shipping industry because its fuel properties similar to that of bunker fuel.

Objectives: There has been extensive research in evaluating chronic pain in the context of litigation while considering the implications that it can have on healthcare outcomes and rehabilitation progress. The aim of this article is to present retrospective observational data about the levels of disability and distress reported by patients with ongoing litigation at the start and following a UK-based multi-disciplinary pain management programme (PMP) when compared with those without litigation. Method: Between June 2014 and September 2017, 859 patients attended and completed a 16-day PMP at a tertiary-level National Health Service (UK) pain clinic. Patients were split into two groups: (1) litigation (n = 110) and (2) non-litigation (n = 749). As a part of the assessment procedure, the patients were given a battery of psychological and physical measures to complete over two time points. Results: Patients with litigation are statistically significantly more distressed at assessment but make comparable clinically meaningful change in PMP intervention when compared with a non-litigation sample. A very small proportion of the variance in depression scores post-treatment is accounted for by the context of litigation (0.5%), which may be accounted for by employment status. There was no effect of litigation on physical outcome post-intervention. Discussion: This article concludes that it is not appropriate to merely assume that the context of litigation results in limited positive psychological and physical outcomes post-PMP. There are some limitations to the clinical sample presented in respect to the conclusions.

Identification of volcanic signals preserved in paleoenvironmental records can provide key insights into the timing and consequences of explosive volcanism. Yet the eruption record is incomplete and this confounds our ability to link volcanic eruptions to their impacts on climate and environments. Studies have suggested that stalagmite records can help to address these gaps, through the identification of transient geochemical variability associated with incorporation of elements derived from erupted material. However, the utility of stalagmites for tracing volcanism is poorly constrained globally. Here, we present a high-resolution geochemical dataset for stalagmite NIED08–05 from Niedźwiedzia Cave (Poland). We do this with two primary aims: (1) to test the suitability of NIED08–05 as a record of volcanism since 3 ka BP, and (2) to ascertain whether stalagmites grown in temperate regions preserve volcanic signals with success comparable to those grown in tropical regions. We find transient enrichments of 16 trace elements and the rare-earth-elements Y, La, Nd, which coincide with the timing of some known eruption events. Using Principal Component Analysis (PCA) we find that elements atypically incorporated into calcite (e.g., Fe) co-vary. Similarly, filtering PC1 (17% of the dataset variability) for high magnitude deviations from a baseline signal yields tentative agreement between PC scores and some known large eruptions with tephra found in Poland. We use our analysis to discuss the complexities involved in associating volcanic signals with stalagmite chemistry in temperate regions far from the source of large eruptions. The transport pathway from volcanic source to stalagmite growth surfaces includes the complex Niedźwiedzia Cave hydrological system and is influenced by dense forest above the cave site. Together these factors increase the potential for attenuation of volcanic-derived chemical signals prior to reaching the stalagmite, and so make it difficult to unambiguously link trace element enrichments in NIED08–05 to volcanic eruptions. Our results provide strong evidence that in a temperate depositional environment far from active volcanoes, climate and hydrology conspire to mute the strength of volcanic geochemical signals. Therefore, this work provides important incentives for future research in this area by highlighting that stalagmites grown in a comparatively simple hydrological regime and grown in caves overlain by thin vegetation and soil cover , may preserve volcanic signatures with greater success than those grown in temperate environments.

This paper describes a condensed version of psychodynamic interpersonal therapy (PIT), Psychodynamic Interpersonal-Empathy (PI-E), which consists of the first level of competencies of the PIT model. The intention is to use basic psychodynamic principles and skills to enhance delivery of manualised, cognitive therapy based treatments. The intervention is designed to improve two common factors of therapy: the bond between client and therapist, and the ability of the therapist to create positive expectations through an explanation and understanding of the person’s problems. Both of these so-called common factors are consistently associated with clinical outcomes. Training has been developed specifically for low-intensity therapists who are employed in the Improving Access to Psychological Treatment programme. Training focuses upon 5 basic components of PI: negotiation; picking up cues;using statements rather than questions; focusing on feelings and understanding hypotheses. When used skilfully together, these simple components, offer a powerful way of empathizing with and deepening the collaborative work with the client. They all help the therapist to focus upon how the client is feeling ‘here and now’ in the session. Training in the model has the potential to improve outcomes and reduce drop-out rates by enabling therapists to manage problem scenarios in an empathic way.

The Younger Dryas is considered the archetypal millennial-scale climate change event, and identifying its cause is fundamental for thoroughly understanding climate systematics during deglaciations. However, the mechanisms responsible for its initiation remain elusive, and both of the most researched triggers (a meltwater pulse or a bolide impact) are controversial. Here, we consider the problem from a different perspective and explore a hypothesis that Younger Dryas climate shifts were catalysed by the unusually sulfur-rich 12.880 ± 0.040 ka BP eruption of the Laacher See volcano (Germany). We use the most recent chronology for the GISP2 ice core ion dataset from the Greenland ice sheet to identify a large volcanic sulfur spike coincident with both the Laacher See eruption and the onset of Younger Dryas-related cooling in Greenland (i.e. the most recent abrupt Greenland millennial-scale cooling event, the Greenland Stadial 1, GS-1). Previously published lake sediment and stalagmite records confirm that the eruption's timing was indistinguishable from the onset of cooling across the North Atlantic but that it preceded westerly wind repositioning over central Europe by ∼ 200 years. We suggest that the initial short-lived volcanic sulfate aerosol cooling was amplified by ocean circulation shifts and/or sea ice expansion, gradually cooling the North Atlantic region and incrementally shifting the midlatitude westerlies to the south. The aerosol-related cooling probably only lasted 1–3 years, and the majority of Younger Dryas-related cooling may have been due to the sea-ice–ocean circulation positive feedback, which was particularly effective during the intermediate ice volume conditions characteristic of ∼ 13 ka BP. We conclude that the large and sulfur-rich Laacher See eruption should be considered a viable trigger for the Younger Dryas. However, future studies should prioritise climate modelling of high-latitude volcanism during deglacial boundary conditions in order to test the hypothesis proposed here.

With the availability of improved hardware and local point-spread function modelling, the presence of patient motion has become a major barrier to further improvements in the quality of PET images and their clinical efficacy. Although numerous approaches to compensate for patient motion have been proposed and are even commercially available, the additional hardware and extended setup time can preclude their routine clinical use. The MR modality on combined PET and MR (PET/MR) scanners can be used to correct motion with almost no additional setup time but currently must replace other MR acquisitions that may be required for clinic use. To overcome these problems, principal component analysis (PCA) and other data-driven techniques have been demonstrated to be able to reliably provide a signal related to patient motion based on raw PET data. Typically, these signals are used to split the PET acquisition into a discrete set of approximately motionfree time segments. This work introduces an approach where the PCA-signals are used as direct surrogates for the motion and regressed against rigid head motion parameters, enabling continuous pose estimation. A proof-of-concept is presented in which the approach is applied to upsample a low temporal resolution MR motion estimate. This proof-of-concept uses rapid echo planar imaging (EPI) data together with PET-derived motion signals. In a comparison of four techniques, nearest neighbour (NN) and linear temporal interpolation and linear and radial basis function (RBF) regression of pose against the PCA surrogate, we demonstrate that the model can be used to accurately interpolate pose continuously throughout the scan.

Igneous sills and dykes that intrude pervasively into prospective sedimentary basins are a common occurrence in volcanic margins, impacting the petroleum system and causing geological and technical drilling challenges during hydrocarbon exploration. The Faroe-Shetland Basin (FSB), NE Atlantic Margin, has been the focus of exploration for over 45 years, with many wells penetrating igneous intrusions. Utilising 29 FSB wells (with 251 intrusions) and 3D seismic data, this study presents new insights into the impacts that igneous intrusions have on hydrocarbon exploration. Examination of cores reveals additional igneous material in individual wells, compared to estimates using seismic or petrophysical data alone, leading to potential underestimation of the volume of the igneous component in a basin. Furthermore, analysis of petrophysical data shows that within the FSB there are silicic intrusions such as diorite and rhyolite, in addition to the commonly encountered mafic intrusions. These silicic intrusions are difficult to recognise in seismic and petrophysical data due to their low density and compressional velocity and have historically been misidentified on seismic reflection data as exploration targets. Drilling data acquired through intrusions provide valuable insight into the problems exploration wells can encounter, often unexpectedly, many of which can be detrimental to safe drilling practice and result in prolonged non-productive time.

At the base of many flood basalt sequences and along volcanic rifted margins, volcanism can compete with the existing sedimentary environments, resulting in interbedded sequences of volcanic rocks and sediments. Here we report on sediment interlayers that are found in the lowermost volcanic units of the Etendeka flood basalts in NW Namibia (Twyfelfontein and Awahab formations), part of the much larger Paraná–Etendeka Igneous Province. The sandstone bodies, predominantly eolian dunes, are isolated in a sequence of Lower Cretaceous (∼ 134 Ma) lava flows. The uppermost part or where sediment deposition and lava emplacement is observed to interact is characterized by barchanoid dunes, which were actively migrating during the emplacement of the lava flows. The fossil (isolated by lava) barchan dunes studied in Dune Valley show three characteristically different diagenetic styles. In Dune Valley, each dune body is completely encapsulated by lava, with additional igneous intrusions cutting through some bodies. We recognize three distinct styles of diagenesis: Type 1: fossilised dunes that are red in color and lack major authigenic mineralization, with grain compaction and subsequent porosity loss being the dominant diagenetic process. Type 2: dunes that have been bleached white, which have undergone a more complex diagenetic pathway. Type 2 dunes have abundant calcite, kaolinite, and böhmite as authigenic phases and lack hematite grain coatings. Detrital plagioclase is absent in white dunes (XRD analysis), with pseudomorphs of kaolinite common. This diagenetic assemblage results in the white dunes having lower porosity and permeability compared to the red dunes. The observations are probably due to a flux of carbon dioxide (CO2), hydrogen sulfide (H2S) and/or hydrogen (H2)–rich hydrothermal groundwater derived from igneous intrusions below. Type 3: “hot contact” effects at lava-flow contacts, where the unconsolidated dunes were rapidly indurated during lava emplacement (volcano-eogenesis). Type 3 diagenesis is restricted to << 1 m depth below lava contacts and common in dunes displaying both Type 1 and Type 2 diagenesis. The distribution of diagenetic Types 1 and 2 is dune specific, and throughout Dune Valley approximately half of the dunes have been bleached (e.g., Type 2 diagenesis), whereas diagenetic Type 3 is a hot contact phenomenon and is therefore found along all basal lava and dike contacts. This work has relevance to understanding the development of sediment–lava systems, to hydrocarbon exploration and development in preserved sediment–lava sequences, and the hydrothermal process described provides an example of natural CO2 sequestration.

Hot-wall low pressure chemical vapor deposition (LPCVD) of highly crystalline epitaxial thin-film AlN grown on silicon (1 1 1) substrates is reported for the first time. Deposition was carried out in a modified commercial LPCVD at 1000 °C and 2 torr. Preflow time for the aluminum precursor, trimethylaluminum, was varied to nucleate Al, and the resulting variation in X-ray diffraction (XRD) crystalline AlN peaks is presented. With a 30 s dichlorosilane (SiH 2 Cl 2 ) pretreatment at 700 °C and the optimal TMAl preflow time, the FWHM of the resulting film was 1116 arcsec for the AlN (0 0 2) 2 θ - ω peak, and the AlN (0 0 2) peak had an omega rocking curve FWHM of 1.6°. This AlN film was shown to be epitaxially aligned to the Si (1 1 1) substrate.

SIRF is a powerful PET/MR image reconstruction research tool for processing data and developing new algorithms. In this research, new developments to SIRF are presented, with focus on motion estimation and correction. SIRF’s recent inclusion of the adjoint of the resampling operator allows gradient propagation through resampling, enabling the MCIR technique. Another enhancement enabled registering and resampling of complex images, suitable for MRI. Furthermore, SIRF’s integration with the optimization library CIL enables the use of novel algorithms. Finally, SPM is now supported, in addition to NiftyReg, for registration. Results of MR and PET MCIR reconstructions are presented, using FISTA and PDHG, respectively. These demonstrate the advantages of incorporating motion correction and variational and structural priors. This article is part of the theme issue ‘Synergistic tomographic image reconstruction: part 2’.

We developed a brief (5.5 min), continuous voice-hearing task (VHT) to address the limitations of existing paradigms used to study auditory verbal hallucinations in the laboratory. Correlational analysis of VHT data obtained from ordinary participants indicated that false alarm responses on the task were reliable and had convergent and divergent validity. Advantages of the VHT over other similar tasks include its sound psychometric properties, brevity, flexibility, control over confounding factors, suitability for multi-task study, and potential for broader application.

Idiopathic environmental intolerance refers to a group of poorly understood health conditions characterized by heterogeneous somatic symptoms that occur in response to environmental triggers, but for which no physiological causes can be found. We focus on three varieties, namely symptoms attributed to (a) chemical substances, (b) electromagnetic fields, and (c) infrasound and vibroacoustic sources. As no clear link with organ pathology or dysfunction has been established so far, we review critical evidence about alternative causal mechanisms as a platform for a novel unifying model of these conditions. There is consistent evidence that expectancy and nocebo mechanisms are critically involved. Using recent predictive coding models of brain functioning, we describe a comprehensive new model to explain how symptoms come about and become linked to specific environmental cues. This new model integrates phenomenally different pathologies, suggests testable new hypotheses, and specifies implications for treatment.

Many prospective sedimentary basins contain a variety of extrusive volcanic products that are ultimately sourced from volcanoes. However, seismic reflection-based studies of magmatic rift basins have tended to focus on the underlying magma plumbing system, meaning that the seismic characteristics of volcanoes are not well understood. Additionally, volcanoes have similar morphologies to hydrothermal vents, which are also linked to underlying magmatic intrusions. In this study, we use high resolution 3D seismic and well data from the Bass Basin, offshore southern Australia, to document 34 cone- and crater-type vents of Miocene age. The vents overlie magmatic intrusions and have seismic properties indicative of a volcanic origin: their moderate–high amplitude upper reflections and zones of “wash-out” and velocity pull-up beneath. The internal reflections of the vents are similar to those found in lava deltas, suggesting they are composed of volcaniclastic material. This interpretation is corroborated by data from exploration wells which penetrated the flanks of several vents. We infer that the vents we describe are composed of hyaloclastite and pyroclasts produced during submarine volcanic eruptions. The morphology of the vents is typical of monogenetic volcanoes, consistent with the onshore record of volcanism on the southern Australian margin. Based on temporal, spatial and volumetric relationships, we propose that submarine volcanoes can evolve from maars to tuff cones as a result of varying magma-water interaction efficiency. The morphologies of the volcanoes and their links to the underlying feeder systems are superficially similar to hydrothermal vents. This highlights the need for careful seismic interpretation and characterization of vent structures linked to magmatic intrusions within sedimentary basins.

On December 29, 2013, an isolated vulcanian-type eruption occurred at Chaparrastique volcano (El Salvador) after 12 years of inactivity. The eruption was classified as VEI 2 and produced an ash plume with a maximum height of ~ 9 km. Textural and compositional data from phenocrysts from the erupted products have been integrated with geochemical and isotopic information from bulk rocks to elucidate the magmatic processes responsible for the reawakening of volcanic activity. Phenocrysts consist of Fo-rich poikilitic olivines hosting high-Mg titanomagnetites, and Fo-poor olivines coexisting with low-Mg titanomagnetites. Mineral-melt equilibria suggest an origin for the distinct phenocryst populations by mixing between a high- T (~ 1130–1150 °C), basaltic magma with f O 2 (NNO buffer) typical of the lower crust in arc systems and a low- T (~ 1060–1080 °C), basaltic andesitic magma with f O 2 (NNO + 1 buffer) commonly encountered in shallower, more oxidized crustal reservoirs. Thermobarometry based on Fe-Mg exchange between orthopyroxene and clinopyroxene constrains the crystallization before eruption at relative low- P (~ 150–250 MPa) and low- T (~ 1000–1050 °C). Mixing between two chemically distinct magmas is also evidenced by the occurrence of reverse zoned plagioclase phenocrysts with resorbed sodic cores and re-growth of sieve-textured calcic mantles. Conversely, plagioclase rims exhibit disequilibrium compositions addressed to decompression kinetics (~ 10 − 3 MPa/s) driven by rapid magma ascent to the surface (~ 0.03 m/s). Major and trace element modelling excludes fractional crystallization as the primary mechanism controlling the bulk rock variability, whereas geochemical data align along a mixing trend between two end-members representative of the primitive basalt and the differentiated basaltic andesite. Trace element and isotope data indicate that the primary source of magmatism is an enriched MORB-like mantle with the contribution of fluxes of metasomatic fluids and/or melts produced by the subducted slab. The role played by slab-fluid inputs of carbonate origin and slab-melts from the hemipelagic sediments seems to be minimal. Assimilation/contamination processes of magmas by crustal rocks are also negligible. In contrast, the geochemical signature of magmas is greatly influenced by slab-derived aqueous fluids produced prevalently by progressive dehydration of marine sediments and altered basaltic crust.

Ocean island volcanoes erupt a wide range of magmatic compositions via a diverse range of eruptive styles. Understanding where and how these melts evolve is thus an essential component in the anticipation of future volcanic activity. Here we examine the role of crustal structure and magmatic flux in controlling the location, evolution and ultimately composition of melts at Ascension Island. Located in the South Atlantic, Ascension Island is an ocean island volcano that has produced a continuum of eruptive compositions from basalt to rhyolite in its 1 Myr subaerial eruptive history. Volcanic rocks broadly follow a silica-undersaturated subalkaline evolutionary trend, and new data presented here show a continuous compositional trend from basalt through trachyte to rhyolite. Detailed petrographic observations are combined with in situ geochemical analyses of crystals and glass, and new whole-rock major and trace element data from mafic and felsic pyroclastic and effusive deposits that span the entire range in eruptive ages and compositions found on Ascension Island. These data show that extensive fractional crystallization is the main driver for the production of felsic melts for Ascension Island, a volcano built on thin, young, oceanic crust. Strong spatial variations in the compositions of erupted magmas reveal the role of a heterogeneous lower crust; differing degrees of interaction with a zone of plutonic rocks are responsible for the range in mafic lava compositions, and for the formation of the central and eastern felsic complexes. A central core of nested, small-scale plutonic, or mush-like, bodies inhibits the ascent of mafic magmas, allowing sequential fractional crystallization within the lower crust, and generating felsic magmas in the core of the island. There is no evidence for magma mixing preserved in any of the studied eruptions, suggesting that magma storage regions are transient, and material is not recycled between eruptions.

This Special Section of the ANZIAM Journal (Electronic Supplement) contains the refereed papers from the 2017 Mathematics for Industry NZ Study Group (MINZ 2017) held at Victoria University, Wellington, New Zealand from 26--30 June, 2017. The MINZ is a special interest meeting of ANZIAM, the Australia and New Zealand Industrial and Applied Mathematics division of the Australian Mathematics Society. MINZ was formed to provide a national entity to host workshops where companies pitch their problems to New Zealand’s mathematical scientists. They then work collaboratively to generate practical solutions through modelling, statistical analysis or computation.

Ash aggregation is a common phenomenon in particle-laden environments of volcanic eruption plumes and pyroclastic density currents. Many of these initially fragile aggregates gain sufficient mechanical strength to remain intact after atmospheric transport and deposition. Several processes contribute to ash aggregate stability, including electrostatic and hydrostatic bonding, ice formation, and cementation by salt precipitates. Here, we compare leachate chemistry from aggregates from a variety of eruption and sedimentation conditions, ranging from dry magmatic eruptions with immediate deposition, to eruptions through seawater. The leachate data shows that the broad window of opportunity for aggregation and aggregate break-up may be used to qualitatively constrain suspended ash concentration and its temporal evolution. We show that aggregation rate and aggregate stability largely depend on the availability of external water and salt source. In particular, high humidity and extensive salt precipitation in seawater environments, such as during the Surtseyan eruptions, promote high aggregation rates and aggregate stability, with accordingly accentuated proximal deposition and aggregate concentration in the deposits. On the other hand, low humidity and salt concentrations during dry magmatic eruptions promote less aggregation and more efficient aggregate break-up, explaining the rarity of aggregates in the deposits. These results have strong implications for the ash budget in volcanic plumes and associated models of plume dispersal and related hazards.

Aims/Objectives Impulse control behaviors (ICBs) affect 15%–35% of Parkinson’s Disease patients. There is evidence of increased carer strain due to these behaviours; however, little is known about clinical variables mediating this effect. This study aims to investigate the factors predictive of carer burden within a cohort of Parkinson’s Disease patients with ICBs. Identification of such factors may allow for targeted therapeutic intervention. Method Data was collected from 45 patients with clinically significant ICBs and their carers including levodopa equivalent daily dosage, assessments of motor and neuropsychiatric symptoms, cognitive function and ICBs. Carer burden was assessed using the Zarit Burden Interview (ZBI). Univariate analyses were performed using Spearman’s Rank Correlation Coefficient. A backward model was used to remove variables to create a final multivariate model using ZBI score as the dependent variable. Results Univariate analysis identified significant correlations between ZBI and total NPI (rs=0.50, p Conclusions This is the largest study to date, looking at associations between carer burden and ICBs. Our findings indicate low mood, poor motivation, social disinhibition and neuropsychiatric symptom burden to be significant factors in carer burden. We also observe that carers reporting poorer health had increased carer strain. Further work should explore methods of physical and psychosocial support and coping strategies for carers.

Motion correction has been added to a PET-MR reconstruction tool, SIRF, by incorporating a registration package, NiftyReg. New functionality has been demonstrated in the context of estimating kinetic parameters in the left temporal lobe, comparing direct and indirect reconstructions and evaluating the impact of using motion correction.Principal component analysis was used to detect motion and to determine time frames, while STIR’s parametric-OSEM was used to perform the motion-corrected direct parametric reconstruction.It was found that the variance in the left temporal lobe decreased when motion correction was performed, and the same was true of direct reconstructions compared to indirect.With SIRF, the entirety of the demonstrated functionality can be performed from a single Matlab or Python script.

The current study aimed to explore the phenomenon of disease-related ‘query escalation’ in high/low health anxious Internet users ( N = 40). During a 15-minute health-related Internet search, participants rated their anxiety and the perceived seriousness of information on each page. Post-search interviews determined the reasons for, and effects of, escalating queries to consider serious diseases. Both groups were found to be significantly more anxious after escalating queries. The high group was significantly more likely to escalate queries. Evaluating personal relevance of material was the main reason for escalations and moderated anxiety post-escalation. We conclude that searching for online disease information can increase anxiety, particularly for people worried about their health.

Psychogenic Nonepileptic Seizures (PNES) superficially resemble epileptic seizures but are thoughtto have a psychological rather than epileptic basis. Patients with PNES vary widely in terms ofbackground, personality profiles, comorbidities, response to treatment and outcomes. Previousaccounts interpreting these seizures as the activation of dissociated material, a physical manifestationof emotional distress, hard-wired reflex responses, or learned behaviours cannot explain key featuresof the phenomenon. Drawing on a brief review of the literature on etiology, correlates andphenomenology of PNES, this paper integrates existing approaches and data within a novelexplanatory framework that applies to all PNES patients with subjectively involuntary seizures.Following the Integrative Cognitive Model of medically unexplained symptoms, we suggest that thecentral feature of all PNES is the automatic activation of a mental representation of seizures (the“seizure scaffold”) in the context of a high level inhibitory processing dysfunction. This often arisesin response to elevated autonomic arousal, and may disrupt the individual‟s awareness of distressingmaterial, but can become divorced from abnormal autonomic and emotional activity. This modelaccounts both for existing findings and the heterogeneity of patients with PNES, whilst leading to anumber of novel hypotheses against which it can be evaluated.