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Columnar-jointed tuffs (bentonites) are located below the Lower Carboniferous Tideswell Dale Sill, Derbyshire, in an abandoned quarry. There are three zones of prismatic joints, columnar joints (∼60 cm thick and mean column width of 4.1 cm) and massive, conchoidally fractured rock sequentially from the dolerite contact downwards. The rocks are very fine-grained (1–10 µm) and consist mainly of sanidine, interlayered illite/smectite, and hematite, with minor quartz, apatite, montmorillonite, anatase and detrital minerals. High K2O and Fe2O3, low Na2O and low MgO are interpreted as due to alteration of felsic volcanic ash. The bentonite was contact-metamorphosed by the sill to temperatures of c. 300 °C. The progression of fracture geometries, thermal considerations and application of theories of column formation indicate that columns formed downwards away from the sill, due to prograde contact metamorphism of the originally clay-rich bentonite. The formation of columnar fracture networks by shrinkage due to igneous heating may have implications for the effectiveness of bentonite as a barrier for disposal of high-level radioactive waste. Regional dimensions include documenting widespread felsic explosive volcanism and inferring a Triassic oxidation event from palaeomagnetic data.
One of Tom Dishion's most significant contributions to prevention science was the development of affordable, ecologically valid interventions, such as the Family Check-Up, that screen for child and family risk factors broadly, but concentrate family-specific interventions on those with greatest potential for population impact. In the spirit of this approach, investigators examined effects of a brief, universal postnatal home visiting program on child emergency medical care and billing costs from birth to age 24 months. Family Connects is a community-wide public health intervention that combines identification and alignment of community services and resources with brief, postpartum nurse home visits designed to assess risk, provide supportive guidance, and connect families with identified risk to community resources. Over 18 months, families of all 4,777 resident Durham County, North Carolina, births were randomly assigned based on even or odd birth date to receive a postnatal nurse home visiting intervention or services as usual (control). Independently, 549 of these families were randomly selected and participated in an impact evaluation study. Families, blind to study goals, provided written consent to access hospital administrative records. Results indicate that children randomly assigned to Family Connects had significantly less total emergency medical care (by 37%) through age 24 months, with results observed across almost all subgroups. Examination of billing records indicate a $3.17 decrease in total billing costs for each $1 in program costs. Overall, results suggest that community-wide postpartum support program can significantly reduce population rates of child emergency medical care through age 24 months while being cost-beneficial to communities.
Intertidal biofilms are a diverse mixture of bacteria, algae as well as sporelings of macroalgae embedded in a polysaccharid matrix. As the primary colonisers of newly formed surfaces, biofilms undergo a succession of different microbe assemblage until the mature state is reached. A biofilm can act as primary producers and as such recycle nutrients in a habitat. It will influence macrobiota by providing a food source or sending out cues to settlers. Biofilms themselves will be controlled by these settlers. This interaction between bottom-up and top-down plays a crucial part for the functioning of the rocky shore ecosystems. However, the diversity of biolfilms as well as it nature to react quickly to environmental changes makes identification and quantification of the individual compounds a difficult task. Subsequently, the understanding of biofilms in general and intertidal, rocky shore microbe assemblages has always tied to techniques and methods available at the time of study. This chapter focusses on the techniques that have greatly contributed to increasing knowledge of biofilms and discusses their findings. Nonetheless, newly developed methods promise to further this knowledge of the ecological role of biofilms on rocky coastlines.
Herbicide resistance within key driver weeds, such as common waterhemp [Amaranthus tuberculatus (Moq.) Sauer var. rudis (Sauer) Costea and Tardif ], constrains available management options for crop production. Routine surveillance for herbicide resistance provides a mechanism to monitor the development and spread of resistant populations over time. Furthermore, the identification and quantification of resistance mechanisms at the population level can provide information that helps growers develop effective management plans. Populations of Amaranthus spp., including A. tuberculatus, redroot pigweed (Amaranthus retroflexus L.), and Palmer amaranth (Amaranthus palmeri S. Watson), were collected from 51 fields in Ohio during the 2016 growing season. Twenty-four A. tuberculatus populations were screened for resistance to the herbicides lactofen, atrazine, and glyphosate. Phenotypically resistant plants were further investigated to determine the frequency of known resistance mechanisms. Resistance to lactofen was infrequently observed throughout the populations, with 8 of 22 populations exhibiting resistant plants. Within those eight resistant populations, the ΔG210 resistance mechanism was observed in 17 of 30 phenotypically resistant plants, and the remainder lacked all known resistance mechanisms. Resistance to atrazine was observed in 12 of 15 populations; however, a target-site resistance mechanism was not observed in these populations. Resistance to glyphosate was observed in all populations. Gene amplification was the predominant glyphosate-resistance mechanism (147 of 322 plants) in the evaluated populations. The Pro-106-Ser mutation was identified in 24 plants, half of which also possessed gene amplification. In this study, molecular screening generally underestimated the phenotypically observed resistance. Continued mechanism discovery and marker development is required for improved detection of herbicide resistance through molecular assays.
To examine the impact of multiple psychiatric disorders over the lifetime on risk of mortality in the general population.
Data came from a random community-based sample of 1397 adults in Atlantic Canada, recruited in 1992. Major depression, dysthymia, panic disorder, generalised anxiety disorder and alcohol use disorders were assessed using the Diagnostic Interview Schedule (DIS). Vital status of participants through 2011 was determined using probabilistic linkages to the Canadian Mortality Database. Cox proportional hazard models with age at study entry as the time scale were used to investigate the relationship between DIS diagnoses and mortality, adjusted for participant education, smoking and obesity at baseline.
Results suggested that mood and anxiety disorders rarely presented in isolation – the majority of participants experienced multiple psychiatric disorders over the lifetime. Elevated risk of death was found among men with both major depression and dysthymia (HR 2.56; 95% CI 1.12–5.89), depression and alcohol use disorders (HR 2.45; 95% CI 1.18–5.10) and among men and women who experienced both panic disorder and alcohol use disorders (HR 3.80; 95% CI 1.19–12.16).
The experience of multiple mental disorders over the lifetime is extremely common, and associated with increased risk of mortality, most notably among men. Clinicians should be aware of the importance of considering contemporaneous symptoms of multiple psychiatric conditions.
Global inequity in access to and availability of essential mental health services is well recognized. The mental health treatment gap is approximately 50% in all countries, with up to 90% of people in the lowest-income countries lacking access to required mental health services. Increased investment in global mental health (GMH) has increased innovation in mental health service delivery in LMICs. Situational analyses in areas where mental health services and systems are poorly developed and resourced are essential when planning for research and implementation, however, little guidance is available to inform methodological approaches to conducting these types of studies. This scoping review provides an analysis of methodological approaches to situational analysis in GMH, including an assessment of the extent to which situational analyses include equity in study designs. It is intended as a resource that identifies current gaps and areas for future development in GMH. Formative research, including situational analysis, is an essential first step in conducting robust implementation research, an essential area of study in GMH that will help to promote improved availability of, access to and reach of mental health services for people living with mental illness in low- and middle-income countries (LMICs). While strong leadership in this field exists, there remain significant opportunities for enhanced research representing different LMICs and regions.
We describe the motivation and design details of the ‘Phase II’ upgrade of the Murchison Widefield Array radio telescope. The expansion doubles to 256 the number of antenna tiles deployed in the array. The new antenna tiles enhance the capabilities of the Murchison Widefield Array in several key science areas. Seventy-two of the new tiles are deployed in a regular configuration near the existing array core. These new tiles enhance the surface brightness sensitivity of the array and will improve the ability of the Murchison Widefield Array to estimate the slope of the Epoch of Reionisation power spectrum by a factor of ∼3.5. The remaining 56 tiles are deployed on long baselines, doubling the maximum baseline of the array and improving the array u, v coverage. The improved imaging capabilities will provide an order of magnitude improvement in the noise floor of Murchison Widefield Array continuum images. The upgrade retains all of the features that have underpinned the Murchison Widefield Array’s success (large field of view, snapshot image quality, and pointing agility) and boosts the scientific potential with enhanced imaging capabilities and by enabling new calibration strategies.
The goal of this study was to assess the utility of serial electrocardiograms in routine follow-up of paediatric Marfan patients.
Children ⩽18 years who met the revised Ghent criteria for Marfan syndrome and received a 12-lead electrocardiogram and echocardiogram within a 3-month period were included. Controls were matched by age, body surface area, gender, race, and ethnicity, and consisted of patients assessed in clinic with a normal cardiac evaluation. Demographic, clinical, echocardiographic, and electrocardiographic data were collected.
A total of 45 Marfan patients (10.8 [2.4–17.1] years) and 37 controls (12.8 [1.3–17.1] years) were included. Left atrial enlargement and left ventricular hypertrophy were more frequently present on 12-lead electrocardiogram of Marfan patients compared with controls (12 (27%) versus 0 (0%), p<0.001; and 8 (18%) versus 0 (0%), p=0.008, respectively); however, only two patients with left atrial enlargement on 12-lead electrocardiogram were confirmed to have left atrial enlargement by echocardiogram, and one patient had mild left ventricular hypertrophy by echocardiogram, not appreciated on 12-lead electrocardiogram. QTc interval was longer in Marfan patients compared with controls (427±16 versus 417±22 ms, p=0.03), with four Marfan patients demonstrating borderline prolonged QTc intervals for gender.
While Marfan patients exhibited a higher frequency of left atrial enlargement and left ventricular hypertrophy on 12-lead electrocardiograms compared with controls, these findings were not supported by echocardiography. Serial 12-lead electrocardiograms in routine follow-up of asymptomatic paediatric Marfan patients may be more appropriate for a subgroup of Marfan patients only, specifically those with prolonged QTc interval at their baseline visit.
The rate of antidepressant use in the United Kingdom has outpaced diagnostic increases in the prevalence of depression. Research has suggested that personal and socioeconomic risk factors may be contributing to antidepressant use. To date, few studies have addressed these possible contributions. Thus, this study aimed to assess the relative strength of personal, socioeconomic and trauma-related risk factors in predicting antidepressant use.
Data were derived from the Adult Psychiatric Morbidity Survey (n=7403), a nationally representative household sample of adults residing in England in 2007. A multivariate binary logistic regression model was developed to assess the associations between personal, socioeconomic and trauma-related risk factors and current antidepressant use.
The strongest predictor of current antidepressant use was meeting the criteria for an ICD-10 depressive episode [odds ratio (OR)=9.04]. Other significant predictors of antidepressant use in this analysis included English as first language (OR=3.45), female gender (OR=1.98), unemployment (OR=1.82) and childhood sexual abuse (OR=1.53).
Several personal, socioeconomic and trauma-related factors significantly contributed to antidepressant use in the multivariate model specified. These findings aid our understanding of the broader context of antidepressant use in the United Kingdom.
Introduction: Screening for organ and tissue donation is an essential skill for emergency physicians. In 2015, 4564 individuals were on a waiting list for organ transplant and 242 died while waiting. As Canadas donation rates are less than half that of other comparable countries, it is crucial to ensure we are identifying all potential donors. Patients deceased from poisoning are a source that may not be considered for referral as often as those who die from other causes. This study aims to identify if patients dying from poisoning represent an under-referred group and determine what physician characteristics influence referral decisions. Methods: In this cross-sectional unidirectional survey study, physician members of the Canadian Association of Emergency Physicians were invited to participate. Participants were presented with 20 organ donation scenarios that included poisoned and non-poisoned deaths, as well as one ideal scenario for organ or tissue donation used for comparison. Participants were unaware of the objective to explore donation in the context of poisoning deaths. Following the organ donation scenarios, a range of follow-up questions and demographics were included to explore factors influencing the decision to refer or not refer for organ or tissue donation. Results were reported descriptively and associations between physician characteristics and decisions to refer were assessed using odds ratios and 95% confidence intervals. Results: 208/2058 (10.1%) physicians participated. 25% did not refer in scenarios involving a drug overdose (n=71). Specific poisonings commonly triggering the decision to not refer included palliative care medications (n=34, 18%), acetaminophen (n=42, 22%), chemical exposure (n=48, 27%) and organophosphates (n=87, 48%). Factors associated with an increased likelihood to refer potential donors following overdose included previous organ and tissue donation training (OR=2.6), having referred in the past (OR=4.3), available donation support (OR=3.9), greater than 10 years of service (OR=2.1), large urban center (OR=3.8), holding emergency medicine certification (OR=3.6), male gender (OR=2.2, CI), and having indicated a desire to be a donor on government identification (OR=5.8). Conclusion: Scenarios involving drug overdoses were associated with under-referral for organ and tissue donation. As poisoning is not a contraindication for referral, this represents a potential source of donors. By examining characteristics that put clinicians at risk for under-referral of organ or tissue donors, becoming aware of potential biases, improving transplant knowledge bases, and implementing support and training programs for the organ and tissue donation processes, we have the opportunity to improve these rates and reduce morbidity and mortality for Canadians requiring organ or tissue donation.
Most basic science research has focused on overt stroke caused by blockage of major blood vessels. Less attention has been paid to small vessel disease giving rise to covert stroke that often leads to vascular cognitive impairment (VCI). One reason for this may be the relative lack of relevant animal models. This talk will describe a model of VCI induced in middle-aged Sprague-Dawley rats exposed to a diet high in saturated fats, salt and refined sugar (HFSS). In Experiment 1, rats fed HFSS and subjected to a small mediodorsal (MD) thalamic stroke with or without concomitant cerebral hypoperfusion experienced significant executive dysfunction. In Experiment 2, dietary influences on functional, physiological and anatomical parameters were assessed. We found significant hypertension, blockage of brain microvessels (2-photon microscopy) and white matter atrophy in HFSS diet animals. As in Experiment 1, profound, specific set-shifting executive dysfunction was noted following both small MD infarcts (0.332 mm3) and the HFSS diet. In summary, these data describe a middle-aged animal model of VCI that includes clinically-relevant metabolic disturbances and small vessel disease and as such may be helpful in developing new cognitive therapies.
We present the first results of the MINDVIEW project. An innovative imaging system for the human brain examination, allowing simultaneous acquisition of PET/MRI images, has been designed and constructed. It consists of a high sensitivity and high resolution PET scanner integrated in a novel, head-dedicated, radio frequency coil for a 3T MRI scanner. Preliminary measurements from the PET scanner show sensitivity 3 times higher than state-of-the-art PET systems that will allow safe repeated studies on the same patient. The achieved spatial resolution, close to 1 mm, will enable differentiation of relevant brain structures for schizophrenia. A cost-effective and simple method of radiopharmaceutical production from 11C-carbon monoxide and a mini-clean room has been demonstrated. It has been shown that 11C-raclopride has higher binding potential in a new VAAT null mutant mouse model of schizophrenia compared to wild type control animals. A significant reduction in TSPO binding has been found in gray matter in a small sample of drug-naïve, first episode psychosis patients, suggesting a reduced number or an altered function of immune cells in brain at early stage schizophrenia.
We present the first data release of the SkyMapper Southern Survey, a hemispheric survey carried out with the SkyMapper Telescope at Siding Spring Observatory in Australia. Here, we present the survey strategy, data processing, catalogue construction, and database schema. The first data release dataset includes over 66 000 images from the Shallow Survey component, covering an area of 17 200 deg2 in all six SkyMapper passbands uvgriz, while the full area covered by any passband exceeds 20 000 deg2. The catalogues contain over 285 million unique astrophysical objects, complete to roughly 18 mag in all bands. We compare our griz point-source photometry with Pan-STARRS1 first data release and note an RMS scatter of 2%. The internal reproducibility of SkyMapper photometry is on the order of 1%. Astrometric precision is better than 0.2 arcsec based on comparison with Gaia first data release. We describe the end-user database, through which data are presented to the world community, and provide some illustrative science queries.
The global spread of non-tuberculous mycobacteria (NTM) may be due to HIV/AIDS and other environmental factors. The symptoms of NTM and tuberculosis (TB) disease are indistinguishable, but their treatments are different. Lack of research on the epidemiology of NTM infections has led to underestimation of its prevalence within TB endemic countries. This study was designed to determine the prevalence and clinical characteristics of pulmonary NTM in Bamako. A cross-sectional study which include 439 suspected cases of pulmonary TB. From 2006 to 2013 a total of 332 (76%) were confirmed to have sputum culture positive for mycobacteria. The prevalence of NTM infection was 9.3% of our study population and 12.3% of culture positive patients. The seroprevalence of HIV in NTM group was 17.1%. Patients who weighed <55 kg and had TB symptoms other than cough were also significantly more likely to have disease due to NTM as compared to those with TB disease who were significantly more likely to have cough and weigh more than 55 kg (OR 0.05 (CI 0.02–0.13) and OR 0.32 (CI 0.11–0.93) respectively). NTM disease burden in Bamako was substantial and diagnostic algorithms for pulmonary disease in TB endemic countries should consider the impact of NTM.
The World Health Organization will publish its 11th revision of the International Classification of Diseases (ICD-11) in 2018. The ICD-11 will include a refined model of posttraumatic stress disorder (PTSD) and a new diagnosis of complex PTSD (CPTSD). Whereas emerging data supports the validity of these proposals, the discriminant validity of PTSD and CPTSD have yet to be tested amongst a sample of refugees.
Treatment-seeking Syrian refugees (N = 110) living in Lebanon completed an Arabic version of the International Trauma Questionnaire; a measure specifically designed to capture the symptom content of ICD-11 PTSD and CPTSD.
In total, 62.6% of the sample met the diagnostic criteria for PTSD or CPTSD. More refugees met the criteria for CPTSD (36.1%) than PTSD (25.2%) and no gender differences were observed. Latent class analysis results identified three distinct groups: (1) a PTSD class, (2) a CPTSD class and (3) a low symptom class. Class membership was significantly predicted by levels of functional impairment.
Support for the discriminant validity of ICD-11 PTSD and CPTSD was observed for the first time within a sample of refugees. In support of the cross-cultural validity of the ICD-11 proposals, the prevalence of PTSD and CPTSD were similar to those observed in culturally distinct contexts.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
The Molonglo Observatory Synthesis Telescope (MOST) is an 18000 m2 radio telescope located 40 km from Canberra, Australia. Its operating band (820–851 MHz) is partly allocated to telecommunications, making radio astronomy challenging. We describe how the deployment of new digital receivers, Field Programmable Gate Array-based filterbanks, and server-class computers equipped with 43 Graphics Processing Units, has transformed the telescope into a versatile new instrument (UTMOST) for studying the radio sky on millisecond timescales. UTMOST has 10 times the bandwidth and double the field of view compared to the MOST, and voltage record and playback capability has facilitated rapid implementaton of many new observing modes, most of which operate commensally. UTMOST can simultaneously excise interference, make maps, coherently dedisperse pulsars, and perform real-time searches of coherent fan-beams for dispersed single pulses. UTMOST operates as a robotic facility, deciding how to efficiently target pulsars and how long to stay on source via real-time pulsar folding, while searching for single pulse events. Regular timing of over 300 pulsars has yielded seven pulsar glitches and three Fast Radio Bursts during commissioning. UTMOST demonstrates that if sufficient signal processing is applied to voltage streams, innovative science remains possible even in hostile radio frequency environments.
We present techniques developed to calibrate and correct Murchison Widefield Array low-frequency (72–300 MHz) radio observations for polarimetry. The extremely wide field-of-view, excellent instantaneous (u, v)-coverage and sensitivity to degree-scale structure that the Murchison Widefield Array provides enable instrumental calibration, removal of instrumental artefacts, and correction for ionospheric Faraday rotation through imaging techniques. With the demonstrated polarimetric capabilities of the Murchison Widefield Array, we discuss future directions for polarimetric science at low frequencies to answer outstanding questions relating to polarised source counts, source depolarisation, pulsar science, low-mass stars, exoplanets, the nature of the interstellar and intergalactic media, and the solar environment.
We present low-frequency spectral energy distributions of 60 known radio pulsars observed with the Murchison Widefield Array telescope. We searched the GaLactic and Extragalactic All-sky Murchison Widefield Array survey images for 200-MHz continuum radio emission at the position of all pulsars in the Australia Telescope National Facility (ATNF) pulsar catalogue. For the 60 confirmed detections, we have measured flux densities in 20 × 8 MHz bands between 72 and 231 MHz. We compare our results to existing measurements and show that the Murchison Widefield Array flux densities are in good agreement.