Connectome dysfunction in patients at clinical high risk for psychosis and modulation by oxytocin.

Abnormalities in functional brain networks (functional connectome) are increasingly implicated in people at Clinical High Risk for Psychosis (CHR-P). Intranasal oxytocin, a potential novel treatment for the CHR-P state, modulates network topology in healthy individuals. However, its connectomic effects in people at CHR-P remain unknown. Forty-seven men (30 CHR-P and 17 healthy controls) received acute challenges of both intranasal oxytocin 40 IU and placebo in two parallel randomised, double-blind, placebo-controlled cross-over studies which had similar but not identical designs. Multi-echo resting-state fMRI data was acquired at approximately 1 h post-dosing. Using a graph theoretical approach, the effects of group (CHR-P vs healthy control), treatment (oxytocin vs placebo) and respective interactions were tested on graph metrics describing the topology of the functional connectome. Group effects were observed in 12 regions (all pFDR < 0.05) most localised to the frontoparietal network. Treatment effects were found in 7 regions (all pFDR < 0.05) predominantly within the ventral attention network. Our major finding was that many effects of oxytocin on network topology differ across CHR-P and healthy individuals, with significant interaction effects observed in numerous subcortical regions strongly implicated in psychosis onset, such as the thalamus, pallidum and nucleus accumbens, and cortical regions which localised primarily to the default mode network (12 regions, all pFDR < 0.05). Collectively, our findings provide new insights on aberrant functional brain network organisation associated with psychosis risk and demonstrate, for the first time, that oxytocin modulates network topology in brain regions implicated in the pathophysiology of psychosis in a clinical status (CHR-P vs healthy control) specific manner.

Cannabis points to the synaptic pathology of mental disorders: how aberrant synaptic components disrupt the highest psychological functions
.

Cannabis can elicit an acute psychotic reaction, and its long-term use is a risk factor for schizophrenia. The main active psychoactive ingredient ∆9-tetrahydrocannabinol (Δ9-THC) activates cannabinoid 1 (CB1) receptors, which are localized to the terminals of glutamate and GABA neurons in the brain. The endogenous cannabinoids are involved in information processing and plasticity at synapses in the hippocampus, basal ganglia, and cerebral cortex. Exogenously applied CB1 receptor agonists disrupt neuronal dynamics and synaptic plasticity, resulting in cognitive deficits and impairment of the highest psychological functions. Various other pro-psychotic drugs, such as ketamine and methamphetamine, exert their effects in the same microdomain of synaptic spines as Δ9-THC. Additionally, many of the most robust findings in psychiatric genetics include components that localize to dendritic spines and have important roles in information processing and plasticity.
.

La cannabis puede provocar una reacción psicótica aguda y su empleo a largo plazo es un factor de riesgo para esquizofrenia. El principal componente psicoactivo ∆9-tetrahidrocannabinol (Δ9-THC) estimula los receptores cannabinoides CB1, que se localizan en las terminales de las neuronas de glutamato y de GABA cerebrales. Los cannabinoides endógenos participan en el procesamiento de la información y la plasticidad en las sinapsis del hipocampo, los ganglios basales y la corteza cerebral. Los agonistas de CB1 administrados de forma exógena interrumpen la dinámica neuronal y la plasticidad sináptica, lo que se traduce en déficits cognitivos y deterioro de las funciones psicológicas más altas. Varias otras drogas propsicóticas, como la ketamina y la metanfetamina, ejercen sus efectos en el mismo microdominio de espinas sinápticas que el Δ9-THC. Además, muchos de los hallazgos más consistentes en genética psiquiátrica incluyen componentes que se localizan en las espinas dendríticas y tienen funciones importantes en el procesamiento y la plasticidad de la información.

Le cannabis peut provoquer une réaction psychotique aiguë et sa consommation à long terme est un facteur de risque de schizophrénie. Le ∆9-tétrahydrocannabinol (Δ9-THC), principal ingrédient psychoactif, active les récepteurs cannabinoïdes CB1 situés aux extrémités des neurones glutamatergiques et GABAergiques dans le cerveau. Les cannabinoïdes endogènes participent au traitement de l'information et à la plasticité des synapses dans l'hippocampe, les ganglions de la base et le cortex cérébral. Les agonistes CB1 exogènes perturbent la dynamique neuronale et la plasticité synaptique, entraînant des déficits cognitifs et une altération des fonctions psychologiques les plus hautes. D'autres drogues propsychotiques, telles la kétamine et la méthamphétamine, agissent dans le même micro-domaine des épines synaptiques que le Δ9-THC. De plus, de nombreuses recherches en génétique psychiatrique ont mis en évidence des composés qui jouent un rôle important dans le traitement de l'information et la plasticité en se fixant sur les épines dendritiques.

Predicting COVID-19 Pneumonia Severity on Chest X-ray With Deep Learning.

Introduction The need to streamline patient management for coronavirus disease-19 (COVID-19) has become more pressing than ever. Chest X-rays (CXRs) provide a non-invasive (potentially bedside) tool to monitor the progression of the disease. In this study, we present a severity score prediction model for COVID-19 pneumonia for frontal chest X-ray images. Such a tool can gauge the severity of COVID-19 lung infections (and pneumonia in general) that can be used for escalation or de-escalation of care as well as monitoring treatment efficacy, especially in the ICU. Methods Images from a public COVID-19 database were scored retrospectively by three blinded experts in terms of the extent of lung involvement as well as the degree of opacity. A neural network model that was pre-trained on large (non-COVID-19) chest X-ray datasets is used to construct features for COVID-19 images which are predictive for our task. Results This study finds that training a regression model on a subset of the outputs from this pre-trained chest X-ray model predicts our geographic extent score (range 0-8) with 1.14 mean absolute error (MAE) and our lung opacity score (range 0-6) with 0.78 MAE. Conclusions These results indicate that our model's ability to gauge the severity of COVID-19 lung infections could be used for escalation or de-escalation of care as well as monitoring treatment efficacy, especially in the ICU. To enable follow up work, we make our code, labels, and data available online.

Cannabidiol for the treatment of cannabis use disorder: a phase 2a, double-blind, placebo-controlled, randomised, adaptive Bayesian trial.

Background A substantial and unmet clinical need exists for pharmacological treatment of cannabis use disorders. Cannabidiol could offer a novel treatment, but it is unclear which doses might be efficacious or safe. Therefore, we aimed to identify efficacious doses and eliminate inefficacious doses in a phase 2a trial using an adaptive Bayesian design. METHODS: We did a phase 2a, double-blind, placebo-controlled, randomised, adaptive Bayesian trial at the Clinical Psychopharmacology Unit (University College London, London, UK). We used an adaptive Bayesian dose-finding design to identify efficacious or inefficacious doses at a-priori interim and final analysis stages. Participants meeting cannabis use disorder criteria from DSM-5 were randomly assigned (1:1:1:1) in the first stage of the trial to 4-week treatment with three different doses of oral cannabidiol (200 mg, 400 mg, or 800 mg) or with matched placebo during a cessation attempt by use of a double-blinded block randomisation sequence. All participants received a brief psychological intervention of motivational interviewing. For the second stage of the trial, new participants were randomly assigned to placebo or doses deemed efficacious in the interim analysis. The primary objective was to identify the most efficacious dose of cannabidiol for reducing cannabis use. The primary endpoints were lower urinary 11-nor-9-carboxy-δ-9-tetrahydrocannabinol (THC-COOH):creatinine ratio, increased days per week with abstinence from cannabis during treatment, or both, evidenced by posterior probabilities that cannabidiol is better than placebo exceeding 0·9. All analyses were done on an intention-to-treat basis. This trial is registered with ClinicalTrials.gov (NCT02044809) and the EU Clinical Trials Register (2013-000361-36). FINDINGS: Between May 28, 2014, and Aug 12, 2015 (first stage), 48 participants were randomly assigned to placebo (n=12) and to cannabidiol 200 mg (n=12), 400 mg (n=12), and 800 mg (n=12). At interim analysis, cannabidiol 200 mg was eliminated from the trial as an inefficacious dose. Between May 24, 2016, and Jan 12, 2017 (second stage), randomisation continued and an additional 34 participants were allocated (1:1:1) to cannabidiol 400 mg (n=12), cannabidiol 800 mg (n=11), and placebo (n=11). At final analysis, cannabidiol 400 mg and 800 mg exceeded primary endpoint criteria (0·9) for both primary outcomes. For urinary THC-COOH:creatinine ratio, the probability of being the most efficacious dose compared with placebo given the observed data was 0·9995 for cannabidiol 400 mg and 0·9965 for cannabidiol 800 mg. For days with abstinence from cannabis, the probability of being the most efficacious dose compared with placebo given the observed data was 0·9966 for cannabidiol 400 mg and 0·9247 for cannabidiol 800 mg. Compared with placebo, cannabidiol 400 mg decreased THC-COOH:creatinine ratio by -94·21 ng/mL (95% interval estimate -161·83 to -35·56) and increased abstinence from cannabis by 0·48 days per week (0·15 to 0·82). Compared with placebo, cannabidiol 800 mg decreased THC-COOH:creatinine ratio by -72·02 ng/mL (-135·47 to -19·52) and increased abstinence from cannabis by 0·27 days per week (-0·09 to 0·64). Cannabidiol was well tolerated, with no severe adverse events recorded, and 77 (94%) of 82 participants completed treatment. INTERPRETATION: In the first randomised clinical trial of cannabidiol for cannabis use disorder, cannabidiol 400 mg and 800 mg were safe and more efficacious than placebo at reducing cannabis use. FUNDING: Medical Research Council.

Acute oxytocin effects in inferring others' beliefs and social emotions in people at clinical high risk for psychosis.

Social deficits are key hallmarks of the Clinical High Risk for Psychosis (CHR-P) state and of established psychotic disorders, and contribute to impaired social functioning, indicating a potential target for interventions. However, current treatments do not significantly ameliorate social impairments in CHR-P individuals. Given its critical role in social behaviour and cognition, the oxytocinergic (OT) system is a promising target for novel interventions in CHR-P subjects. In a double-blind, placebo-controlled, crossover design, 30 CHR-P males were studied using functional magnetic resonance imaging (fMRI) on two occasions, once after 40IU self-administered intranasal OT and once after placebo. A modified version of the Sally-Anne task was used to assess brain activation during inferring others' beliefs and social emotions. The Reading the Mind in the Eyes Test was acquired prior to the first scan to test whether OT effects were moderated by baseline social-emotional abilities. OT did not modulate behavioural performances but reduced activation in the bilateral inferior frontal gyrus compared with placebo while inferring others' social emotions. Furthermore, the relationship between brain activation and task performance after OT administration was moderated by baseline social-emotional abilities. While task accuracy during inferring others' social emotion increased with decreasing activation in the left inferior frontal gyrus in CHR-P individuals with low social-emotional abilities, there was no such relationship in CHR-P individuals with high social-emotional abilities. Our findings may suggest that acute OT administration enhances neural efficiency in the inferior frontal gyrus during inferring others' social emotions in those CHR-P subjects with low baseline social-emotional abilities.

Glyceryl trinitrate in first-episode psychosis unmedicated with antipsychotics: A randomised controlled pilot study.

BACKGROUND: There is a pressing need for new classes of treatment for psychosis. A key therapeutic target for novel compounds is the NMDA receptor, which may be modulated by nitric oxide donors such as sodium nitroprusside (SNP). Recent studies of SNP in patients with psychosis have mixed results, and the drug has to be administered intravenously. Glyceryl trinitrate (GTN) is a well-established cardiovascular medicine that is also a nitric oxide donor, and can be given orally. AIMS: We explored the safety and potential effects of GTN in unmedicated patients with a first episode of psychosis. METHODS: This was a single-centre, randomised, double-blind, placebo-controlled trial from December 2016 to April 2019 (ClinicalTrials.gov identifier: NCT02906553). Patients received 3 × sprays of GTN or placebo for three consecutive days, and were re-assessed on Days 1, 2, 3 and 7. The primary outcome was cognition (Jumping to Conclusions task), secondary outcomes were symptoms (Positive and Negative Syndrome Scale (PANSS)), verbal memory (Hopkins Verbal Learning task), and mood (Bond-Lader Visual Analogue Scales). RESULTS: Nineteen patients were randomised, and 13 participants were included in the analyses. Compared with placebo, GTN was well tolerated, but was not associated with significant effects on cognition, symptoms, or mood. Bayesian statistics indicate that our results were 2× more likely under the null hypothesis than the alternative hypothesis, providing anecdotal evidence that GTN does not improve psychotic symptoms. CONCLUSIONS: We found no indication of an effect of GTN on symptoms of psychosis or cognition.

Treatment Setting Influences Treatment Modality for Urinary Stone Disease.

OBJECTIVE: To determine whether selection of treatment modality for urinary stone disease differs between primary and outreach healthcare centers, and if patient rurality predicts treatment modality. METHODS: We retrospectively evaluated Extracorporeal shock wave lithotripsy (ESWL) and ureteroscopy (URS) procedural data from the Iowa Office of Statewide Clinical Education Programs (OSCEP) and Iowa Hospital Association (IHA) databases from 2007 to 2014. Geographical data was used to analyze travel metrics and patient proximity to sites of stone treatment. Rural-urban commuting area (RUCA) codes were used to characterize patient rurality. Chi-square tests and t tests were used to compare ESWL and URS patients, and multilevel logistic regression model was used to assess influence of treatment setting on surgical modality. RESULTS: A total of 18,831 stone procedures were performed by urologists in Iowa on patients from Iowa (10,495 URS; 8336 ESWL). Around 2630 procedures occurred at outreach centers. Ureteroscopy comprised 59.7% of procedures at primary centers, but only 31.2% at outreach centers. On multilevel analysis, outreach location was associated with 2.236 OR toward ESWL (P <.001). Individual physician treatment patterns accounted for 32% of treatment variation. Patient rurality was not significantly associated with treatment modality as an independent factor (P = .879). CONCLUSIONS: Wide variation exists in urolithiasis treatment modality selection between outreach and primary centers. Outreach locations perform a significantly higher frequency of ESWL compared to URS, and much of the variation in treatment selection (32%) arises from individual physician practice patterns.

Excitation Energy Dependence of Photoluminescence Quantum Yields in Semiconductor Nanomaterials with Varying Dimensionalities.

The excitation energy dependence (EED) of the photoluminescence quantum yield (ΦPL) of semiconductor nanoparticles with varying dimensionalities is reported. Specifically, the EEDs of CdSe quantum dots, CdSe quantum platelets, CdSe quantum belts, and CdTe quantum wires were determined via measurements of individual ΦPL values and photoluminescence efficiency (PLEff(E)) spectra. There is a general trend of overall decreasing efficiency for radiative recombination with increasing excitation energy. In addition, there are often local minima in the PLEff(E) spectra that are most often at energies between quantum-confinement transitions. The average PL lifetimes of the samples do not depend on the excitation energy, suggesting that the EED of ΦPL arises from charge carrier trapping that competes efficiently with intraband carrier relaxation to the band edge. The local minima in the PLEff(E) spectra are attributed to excitation into optically coupled states that results in the loss of carriers in the semiconductor. The EED data suggest that the PLEff(E) spectra depend on the sample synthesis, preparation, surface passivation, and environment.

Bullying in Fly-In-Fly-Out employees in the Australian resources sector: A cross-sectional study.

BACKGROUND: Workplace bullying has diverse consequences at both the organisational and individual level. Anecdotal reports indicate that workplace bullying is an issue of particular concern for Australian FIFO workers, which may impact on psychosocial distress. However, no prior studies have examined this issue empirically in a FIFO worker cohort. METHODS AND MATERIALS: A cross-sectional survey study design was used to establish the prevalence of bullying in Australian FIFO, antecedents of bullying, and its association with psychosocial distress. Responses were received from 580 FIFO workers in the Australian resources sector. Primary outcome measures were Negative Acts Questionnaire-Revised, Beck Depression Inventory II, and Beck Hopelessness Scale. Logistic regression models were constructed to examine the association between bullying, suicide risk, and clinical depression. RESULTS: Over half of the respondents experienced workplace bullying (55.7%), and about one-third reported moderate or more severe depression (32.3%). Being above the median age (OR = 0.51; 95% CI = 0.31-0.83) and having a supervisor who failed to promote collaboration (OR = 3.04; 95% CI = 1.84-5.04) were both significantly associated with experiencing bullying. Bullying was associated with an almost threefold increase in the likelihood of participants reporting increased suicide risk (OR = 2.70; 95% CI = 1.53-4.76). Bullying was also associated with participants being almost two and a half times more likely to report clinical depression (OR = 2.38; 95% CI = 1.40-4.05). CONCLUSION: The incidence of bullying in Australian FIFO workers has reached alarming proportions. Bullying was significantly associated with higher levels of clinical depression and suicide risk. The results highlight the need to implement in the Australian resource sector interventions that reduce workplace bullying.

Responding to catastrophe: A case study of learning from perinatal death in midwifery practice.

PROBLEM/BACKGROUND: Perinatal death has far reaching emotional effects for all involved in this devastating event. The opportunity for learning as a result of this catastrophe, however, remains unexplored. AIM: To explore midwives' experiences of caring through, and learning from, perinatal death, to better inform the effective planning and delivery of education that optimises both midwifery and self-care. METHODS: A naturalistic interpretive multiple case study design. Seventeen midwives, located in Australia, participated in an online group activity hosted as a blog, followed by telephonic focus groups and in-depth email interviews. FINDINGS: Thematic data analysis revealed seven major themes: Grappling with the reality of perinatal death; Struggling with personal and professional heartache; Seeking the space to grieve as a professional; Being with the woman and her family; Finding a new purpose; Strengthened through support; and Developing the courage to care. DISCUSSION: The initial turmoil and impact of loss reflected the catastrophic nature of perinatal death. Midwives uncovered a journey to acceptance and learning, realising a determination to enhance expertise and discovering value in experiential knowledge. Insecurity regarding competence and confidence to manage perinatal death and bereavement care was highlighted. However, sharing their stories revealed professional fulfilment, personal strength, and solidarity amongst midwives who have endured similar experiences. CONCLUSION: A coordinated approach to support and the dissemination of experiential knowledge and learning could be developed within an online model of narrative sharing and discussion. Debriefing, support and sharing of expertise in this way may foster engagement within and beyond the workplace.

Spatial and temporal variations of trace metal body burdens of live mussels Mytilus galloprovincialis and field validation of the Artificial Mussels in Australian inshore marine environment.

The body burdens of eight trace metals: Cd, Pb, Cu, Zn, Cr, Se, Hg, and As, were measured in live mussels (LMs) Mytilus galloprovincialis at 14 coastal sites in Port Phillip Bay, Victoria, Australia in winter and summer between 2017 and 2018. The spatial and temporal variations of body burdens were evaluated. The results revealed significantly higher body burdens of Cd, Pb, Cu, Zn, Cr, and Hg in summer at the sites where the city centre and industries are located. Elevated levels of most trace metals including 3 toxic, non-essential metals (Cd, Pb, and Hg) were detected in LMs from the site of Geelong. The body burdens of Zn, Cr, Se, and As appeared higher at the sites from the Bellarine Peninsula and the mouth of Port Phillip Bay. Besides, the "Artificial Mussels" (AMs) were deployed at the same sites in summer for 28 d and retrieved when the LMs were collected. The accumulations of the eight metals were compared between AMs and LMs summer results. It indicated significant correlations for Pb, Cu, and Cr, lower correlations in Zn and Hg, and irregular correlations for Se and As. The AM results of Cd were below the detection limit of the analytical method. This study demonstrates that AMs are excellent replacement of LMs for the biomonitoring of multiple kinds of trace metals.

Synthetic cannabinoid use in psychiatric patients and relationship to hospitalisation: A retrospective electronic case register study.

INTRODUCTION AND OBJECTIVES: Cannabis use has been associated with psychosis and with poor outcome in patients with mental illness. Synthetic cannabinoids (SCs) have been suggested to pose an even greater risk to mental health, but the effect on clinical outcome has not been directly measured. In this study, we aimed to investigate the demographics and hospitalisation of psychiatric patients who were SC users. METHODS: We searched the Biomedical Research Centre Clinical Record Interactive Search register for SC users and age- and sex-matched SC non-users who had been psychiatric patients under the South London and Maudsley NHS Trust. We recorded diagnosis, homelessness, cannabis use and the total number of days admitted as an inpatient to secondary and tertiary mental-health services. RESULTS: We identified 635 SC users and 635 age- and sex-matched SC non-users. SC users were significantly more likely to be homeless (χ2=138.0; p<0.0001) and to use cannabis (χ2=257.3; p<0.0001) than SC non-users. SC users had significantly more inpatient days after their first recorded use of SCs than controls (M (SD)=85.5 (199.7) vs. 25.4 (92.32); p<0.0001). Post hoc tests revealed that SC non-users who used cannabis had fewer inpatient days than SC users (p<0.0001), and that non-users of both SC and cannabis had fewer inpatient days than SC non-using cannabis users (p=0.02). CONCLUSIONS: SC use may lead to an increase in the number of days spent in hospital in patients with psychiatric illness. This highlights the need for clinicians to ask specifically about SC use.

Depression, suicide risk, and workplace bullying: a comparative study of fly-in, fly-out and residential resource workers in Australia.

Objectives The primary objective of this study was to establish whether clinical depression and increased suicide risk differed between Australian fly-in, fly-out (FIFO) workers and their residential counterparts in the resources sector. We also sought to identify whether bullying and social support were associated with depression and suicide risk in this cohort. Methods A cross-sectional survey design was used. Completed questionnaires were received from 751 respondents who were employed in the Australian resources sector. Primary outcomes were assessed with the Beck Depression Inventory, Beck Hopelessness Scale and Negative Acts Questionnaire - Revised. A general linear model was used to examine the association between depression, hopelessness and predictive factors. Results The results of a general linear model analysis demonstrated that depression (partial η2 = 0.02; P = 0.01) and hopelessness (partial η2 = 0.02; P = 0.02) were significantly higher in residential than FIFO workers. In addition, bullying was significantly associated with higher levels of depression (partial η2 = 0.11; P = 0.001) and hopelessness (partial η2 = 0.04; P = 0.001). Finally, increased social support was significantly associated with lower depression rates (partial η2 = 0.13; P = 0.001) and hopelessness (partial η2 = 0.14; P = 0.001). Conclusions Interventions should be delivered to reduce depression and hopelessness in Australian resource workers, particularly through addressing workplace bullying and enhancing social support. What is known about the topic? One-third of Australian resource workers experience psychosocial distress. Research examining factors that influence such distress is lacking. What does this paper add? The results of this study demonstrate that clinical depression and suicide risk were significantly higher in residential resource workers than in FIFO workers. Depression and suicide risk were directly associated with workplace bullying. In addition, social support was an important protective factor against depression and bullying in Australian FIFO and residential resource workers. What are the implications for practitioners? There is an urgent need to introduce interventions that reduce psychosocial distress in the resource sector, particularly through the mitigation of bullying.

Reliability and Validity of the 6-Minute Step Test for Clinical Assessment of Cardiorespiratory Fitness in People at Risk of Cardiovascular Disease.

Giacomantonio, N, Morrison, P, Rasmussen, R, and MacKay-Lyons, MJ. Reliability and validity of the 6-minute step test for clinical assessment of cardiorespiratory fitness in people at risk of cardiovascular disease. J Strength Cond Res 34(5): 1376-1382, 2020-The purpose of this study was to determine the test-retest reliability and validity of the 6-minute step test (6MST) as a potential assessment of cardiorespiratory fitness (CRF) of people at risk of cardiovascular disease (CVD). A prospective, cross-sectional, correlational study design was used. A single cohort of 30 adults with 2 or more risk factors for CVD was recruited. Exercise tests were scheduled on 2 days, separated by 1 week. Validity was determined by comparing 6MST results with those obtained in a symptom-limited treadmill test and the 6-minute walk test (6MWT). Main outcome variables were peak heart rate (HRpeak) and peak oxygen consumption (V[Combining Dot Above]O2peak) measured during the 6MST, treadmill test, and 6MWT. Test-retest reliability of HRpeak and V[Combining Dot Above]O2peak during the 6MST was very strong (intraclass correlation coefficient [ICC], 0.92; 95% confidence interval [CI], 0.83-0.97 and ICC, 0.93; 95% CI, 0.84-0.97, respectively). Correlations were also very strong between 6MST and treadmill test HRpeak (r = 0.81) and between 6MST and treadmill test V[Combining Dot Above]O2peak (r = 0.88). Correlations were moderate between 6MST HRpeak and 6MWT steady-state HR (r = 0.57) and strong between 6MST V[Combining Dot Above]O2peak and 6MWT steady-state V[Combining Dot Above]O2 (r = 0.70). The 6MST seems to be a reliable, valid option for assessing CRF of people at risk of CVD in a broad range of clinical settings. Providing practical, accessible tests will help facilitate the goal of establishing CRF as a clinical vital sign. The next step in the development of the 6MST should be to identify the most appropriate 6MST predictor variables to estimate V[Combining Dot Above]O2max.

Trace metal biomonitoring in the east Gippsland Lakes estuary using the barnacle Amphibalanus variegatus and mussel Mytilus edulis.

The Gippsland Lakes estuary, a Ramsar listed wetland, in Victoria, Australia, is an area of potential concern for metal pollution due to influxes of human population and associated anthropogenic activities. A biomonitoring exercise was undertaken where the concentrations of 9 metals (Cr, Fe, Cu, Zn, As, Se, Ag, Cd and Hg) were analysed in the soft tissue of two common sessile invertebrates: the mussel Mytilus edulis and the barnacle Amphibalanus variegatus from 6 locations on two different occasions throughout the Gippsland Lakes estuary. A salinity gradient exists in the Lakes, from seawater at Lakes Entrance in the east, decreasing down to < 10 PSU in the west at Lake Wellington during times of rainfall, which is a major factor governing the growth and distribution of both species. Dissolved metal levels in general were low; however, Cu at most sites exceeded the 90% trigger values, while all Zn concentrations exceeded the lowest 80% trigger values of the ANZECC marine water quality guidelines for environmental health. Elevated levels of Cu and Zn were found particularly in barnacles at some sites with environmental contamination due to leaching from anti fouling paints and sacrificial zinc anodes. Elevated levels of Ag and Cd were found in mussels at the Hollands Landing site, which is immediately adjacent to a boat ramp, and Cd and Ag at this site are suspected to originate from inland anthropogenic sources. Concentrations of As in M. edulis across all 6 sites in both sampling periods had mean wet weight As concentrations exceeding the maximum level stated in the FSANZ guidelines. A. variegatus contained elevated levels of Hg especially at the North Arm site with a maximum of 13.6 µg Hg/g dry wt., while A. variegatus also showed temporal changes in Hg concentrations across sites. The maximum Hg concentration found in Mytilus edulis was 1.49 µg Hg/g dry wt. at the Hollands Landing site. Previous contaminant studies of biota in the Lakes have targeted sampling of singular predatory or migratory species, such as Black Bream (Acanthopagrus butcheri) and the Burrunan dolphin (Tursiops australis). This is the first biomonitoring study conducted on sessile organisms to assess metal contamination in the system.

Influence of Human Activities on Broad-Scale Estuarine-Marine Habitats Using Omics-Based Approaches Applied to Marine Sediments.

Rapid urban expansion and increased human activities have led to the progressive deterioration of many marine ecosystems. The diverse microbial communities that inhabit these ecosystems are believed to influence large-scale geochemical processes and, as such, analyzing their composition and functional metabolism can be a means to assessing an ecosystem's resilience to physical and chemical perturbations, or at the very least provide baseline information and insight into future research needs. Here we show the utilization of organic and inorganic contaminant screening coupled with metabolomics and bacterial 16S rRNA gene sequencing to assess the microbial community structure of marine sediments and their functional metabolic output. The sediments collected from Moreton Bay (Queensland, Australia) contained low levels of organic and inorganic contaminants, typically below guideline levels. The sequencing dataset suggest that sulfur and nitrite reduction, dehalogenation, ammonia oxidation, and xylan degradation were the major metabolic functions. The community metabolites suggest a level of functional homogeneity down the 40-cm core depth sampled, with sediment habitat identified as a significant driver for metabolic differences. The communities present in river and sandy channel samples were found to be the most active, with the river habitats likely to be dominated by photoheterotrophs that utilized carbohydrates, fatty acids and alcohols as well as reduce nitrates to release atmospheric nitrogen and oxidize sulfur. Bioturbated mud habitats showed overlapping faunal activity between riverine and sandy ecosystems. Nitrogen-fixing bacteria and lignin-degrading bacteria were most abundant in the sandy channel and bioturbated mud, respectively. The use of omics-based approaches provide greater insight into the functional metabolism of these impacted habitats, extending beyond discrete monitoring to encompassing whole community profiling that represents true phenotypical outputs. Ongoing omics-based monitoring that focuses on more targeted pathway analyses is recommended in order to quantify the flux changes within these systems and establish variations from these baseline measurements.

Development and Validation of the Performance-Based Situation Awareness Observation Schedule (PBSAOS): The Process and Lessons Learned.

BACKGROUND: No instruments are currently available to assess nursing students' maintenance of situation awareness. The aim of this study was to develop and validate the Performance-Based Situation Awareness Observation Schedule for measuring nursing students' use of situation awareness. METHOD: Twelve expert clinicians participated in a qualitative, reiterative consensus-driven process to establish the content validity of the tool. The tool was then piloted during the delivery of a situation awareness education program for final-year nursing students. Cohen's kappa was used to assess the interrater reliability. RESULTS: The resultant tool comprised 54 items, which captured strategies to maintain situation awareness and task errors that would infer the presence of situation awareness. The values obtained for Cohen's kappa indicated that the level of agreement was at least substantial for approximately 80% of the items. CONCLUSION: This study developed a valid and reliable tool to measure nursing students' use of situation awareness. [J Nurs Educ. 2019;58(8):468-473.].

Australian mental health caregiver burden: a smallest space analysis.

OBJECTIVES: To explore Australian mental health carers' prioritisation of key elements of caregiving and establish the extent to which particular issues contribute to carer burden. DESIGN: Cross-sectional survey. SETTING: All Australian States and Territories. PARTICIPANTS: Responses were received from 231 Australian mental health caregivers. MAIN OUTCOME MEASURES: The Involvement Evaluation Questionnaire was used to assess caregiver burden. RESULTS: Smallest space analysis identified three distinct regions, which we conceptualise as: 1) promoting the safety and health of mental health consumers; 2) impact of caring on caregivers' personal lives and 3) enabling daily living functional recovery of mental health consumers. The analysis demonstrates that carers are most concerned with enabling daily living functional recovery, for which the mean value was considerably higher than the personal impact and promoting safety and health regions. In terms of the individual questionnaire items, the issues of most importance are assisting with self-care, worrying about consumers' future, finances and general health, encouraging consumer involvement in activities and concerns over the treatment consumers are receiving. CONCLUSION: Caregiving often came at significant personal cost. The burden that results from caring for mental health consumers could perhaps be alleviated through the expansion of psychiatric disability services, increasing government financial support and providing tailored psychosocial interventions that meet the needs of families.