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One of the limiting factors to developing plasma thrusters on alternative propellants is the cost associated with changing the diagnostic tools, which are often propellant-dependent. For laser induced fluorescence (LIF), which is typically used for ion velocity distribution measurements to determine ion trajectories and potential profiles, either new lasers need to be bought, which are tuned to the wavelength of the new element's excitation level, or a costly tunable laser is required. A method to use existing LIF setups designed for xenon on any propellant has been demonstrated on a Hall thruster operating on krypton. In the demonstration test, a small amount of xenon (0.01%–4%) was mixed with the main krypton propellant for use as a diagnostic tracer, and xenon ion velocities were measured while also monitoring changes in the mean discharge current and oscillations. High signal-to-noise ratios in LIF data acquired along the channel centerline were obtained with tracer gas fractions ≤1% that negligibly affected the thruster operation. These results and comparison of the emission spectra of xenon and other common propellants suggest that the tracer LIF method should be broadly applicable to LIF measurements in Hall thrusters operating on alternative propellants. [ABSTRACT FROM AUTHOR]

In 2014, the Australian Government established the Teacher Education Ministerial Advisory Group (TEMAG) to advise on how teacher education programmes could ensure new teachers were adequately prepared for the classroom. Following this, the Australian Government endorsed a key recommendation of the TEMAG Action Now: Classroom Ready Teachers report, the inclusion of specialisations in primary Initial Teacher Education (ITE). This research was conducted at an Australian public university that, in 2016, had embedded specialisations in a revised primary teacher programme structure and was one of the first ITE institutions in Australia to graduate primary teachers with a specialisation. Using a mixed-methods case study design with convenience sampling, this study sought to investigate these primary graduates' perceptions of undertaking a specialisation in relation to the development of content knowledge and pedagogical knowledge in the specialist area, as well as perceived employment advantages. This research took place over 4 years with participants having completed a Bachelor of Education (Primary) at least three months prior to participating. The participants reported benefits to having completed a primary specialisation but expressed concerns about their preparedness to teach their specialisation and whether it would result in any advantages for employment. Recommendations from the participants included teaching practice in their area of specialisation, consideration of specialist skills and changing the timetabling of the specialisation in the programme. Ultimately, there is a need for ongoing research in this area to determine the extent to which primary specialisations deliver the intended outcomes and impacts at both the policy driver level and the university level. [ABSTRACT FROM AUTHOR]

This document is a reply to a comment regarding a study on pregnancy outcomes in women with mitochondrial disease. The study was a retrospective analysis of pregnancies in women with genetically confirmed mitochondrial disease. The study acknowledged its limitations, including a small sample size and reliance on maternal recall and retrospective chart review. The study found that gestational diabetes mellitus (GDM) was the initial presentation of glucose intolerance in these women, and it emphasized the importance of increasing awareness of mitochondrial disease among clinicians and obstetricians. [Extracted from the article]

Cloud feedbacks are the leading cause of uncertainty in climate sensitivity. The complex coupling between clouds and the large‐scale circulation in the tropics contributes to this uncertainty. To address this problem, the coupling between clouds and circulation in the latest generation of climate models is compared to observations. Significant biases are identified in the models. The implications of these biases are assessed by combining observations of the present day with future changes predicted by models to calculate observationally constrained feedbacks. For the dynamic cloud feedback (i.e., due to changes in circulation), the observationally constrained values are consistently larger than the model‐only values. This is due to models failing to capture a nonlinear minimum in cloud brightness for weakly descending regimes. Consequently, while the models consistently predict that these regimes increase in frequency in association with a weakening tropical circulation, they underestimate the positive cloud feedback associated with this increase. Plain Language Summary: Climate models are crucial for understanding the impacts of climate change. Yet there are significant differences between models even for the global mean temperature increase due to a doubling of carbon dioxide concentrations (known as the climate sensitivity). These differences in climate sensitivity are largely due to differences in cloud responses to warming between the models (known as cloud feedbacks). Cloud feedback uncertainty is particularly large for tropical clouds. One reason for this is the two‐way interactions between clouds and the large‐scale circulation. This remains relatively poorly understood and involves processes that occur at a wide range of scales which cannot be captured by climate models. This study examines relationships between clouds and circulation in the tropics in the latest generation of climate models. Cloud feedbacks can be separated into dynamic (changes in circulation) and thermodynamic (changes in cloud for a given circulation regime) components. We use this framework to calculate the cloud feedbacks models would predict if the relationships between clouds and circulation matched observations. This results in an increase in the dynamic component of the cloud feedback which is due to the models' failure to capture the observed nonlinear relationships between clouds and circulation. Key Points: Climate models miss key details of the observed links between tropical clouds and circulation, notably for common weak subsidence regimesUsing observations to constrain thermodynamic and dynamic cloud feedbacks in models increases the dynamic and hence total feedbackThis is due to subtle nonlinear changes in the observed SW cloud radiative effect across circulation regimes that the models predict will change in frequency [ABSTRACT FROM AUTHOR]

Aims: The most common pathogenic mitochondrial mutation associated with mitochondrial disease is m.3243A>G. Increased obstetric complications, such as spontaneous abortion, gestational diabetes (GDM), preterm delivery, and preeclampsia, have been reported in women carrying this mutation. We aimed to determine the fetal and maternal outcomes in pregnant women with mitochondrial disease. Methods: We retrospectively studied the obstetric and perinatal outcomes in 88 pregnancies of 26 women with genetically confirmed mitochondrial disease (m.3243A>G in the MTTL1 gene (n = 25); m.12258C>A in the MT-TS2 gene (n = 1)). Outcomes included pregnancy related complications, mode of delivery, gestational age at delivery and birthweight. Results: Mean heteroplasmy rate was 18%. The miscarriage rate was higher than background at 25%. 21 pregnancies (24%) were complicated by GDM; 9 pregnancies (13.6%) had a preterm delivery and 2 of them (3%) an extreme premature delivery < 32 weeks. One woman had preeclampsia and one had a postpartum hemorrhage. The caesarean section (CS) rate was 20%. For every unit increase in maternal heteroplasmy levels there was a 26% increased risk of undergoing an assisted operative vaginal delivery (OR 1.26, 95% CI 1.04–1.53, P = 0.002, Bonferroni corrected P = 0.005) and an 18% increased risk of undergoing a CS (OR 1.18, 95% CI 1.01–1.39, P = 0.01, Bonferroni corrected P = 0.03) compared to a spontaneous vaginal delivery. There was a statistical significant correlation between maternal and offspring heteroplasmy levels. Spearman correlation rho = 0.96, 95% CI 0.78–0.99, P = 0.0002. Conclusion: Women with mitochondrial disease appear to have more frequent obstetric complications including miscarriage and GDM. Pre-pregnancy diagnosis of m.3243A>G will enable the counseling of women and increase awareness of possible obstetric complications. [ABSTRACT FROM AUTHOR]

Aims: Maternally inherited diabetes and deafness (MIDD) is a rare form of adult‐onset diabetes that can be difficult to diagnose due to its variable clinical phenotype. Transfer RNA‐derived small fragments are a novel, emerging class of small non‐coding RNAs (sncRNAs) that have significant potential as serum biomarkers due to their stress‐induced generation, abundance, stability and ease of detection. Methods: We investigated the levels of tiRNA 5'ValCAC (alone and in combination with miR‐23b‐3p) identified from small RNA sequencing studies in serum samples from healthy controls, type 1 diabetes, type 2 diabetes and MIDD subjects. Results: Serum levels of 5'ValCAC were reduced in MIDD and type 2 diabetes subjects compared to controls. Type 2 diabetes subjects had higher serum levels of miR‐23b‐3p compared to all other subjects. Receiver Operating Characteristic analysis showed the potential of 5'ValCAC and miR‐23b‐3p as MIDD biomarkers, with the combination showing excellent separation from type 2 diabetes subjects. Conclusions: This is the first report showing altered serum levels of tiRNAs in diabetes subjects. The combined use of 5'ValCAC and miR‐23b‐3p as serum biomarkers could potentially differentiate between MIDD subjects and type 2 diabetes subjects. [ABSTRACT FROM AUTHOR]

Horizontal temperature gradients in the tropical free troposphere are fairly weak, and tropical tropospheric warming is usually treated as uniform. However, we show here that projected tropospheric warming is spatially inhomogeneous in Coupled Model Intercomparison Project Phase 6 models, as well as in a storm‐resolving climate model. We relate the upper tropospheric warming pattern to sea‐surface temperature changes that reorganise convection and thereby cause spatial shifts in convective heating. Using the classical Gill model for tropical circulation and forcing it with precipitation changes that arise due to greenhouse gas warming, we can understand and reproduce the different warming patterns simulated by a range of global climate models. Forcing the Gill model with precipitation changes from a certain region demonstrates how local tropospheric temperature changes depend on local changes in convective heating. Close to the Equator, anomalous geopotential gradients are balanced by the dissipation term in the Gill model. The optimal dissipation time‐scale to reproduce the warming pattern varies depending on the Coupled Model Intercomparison Project Phase 6 model, and is between 1 and 10 days. We demonstrate that horizontal advection and eddy momentum fluxes have large enough equivalent dissipation time‐scales to balance the gradients in geopotential and thereby shape the warming pattern. Though climate models show a large spread in projections of tropical sea‐surface temperature and precipitation changes, our results imply that, once these predictions improve, our confidence in the predicted upper tropospheric warming pattern should also increase. [ABSTRACT FROM AUTHOR]

This article presents the results of a large-scale international survey conducted by the World Endoscopy Organization (WEO) AI committee on patient perceptions of artificial intelligence (AI) in endoscopy. The survey included 1,237 patients from all six continents, who responded to 13 statements about the use of AI in endoscopy. The majority of patients believed that AI and humans can complement each other and supported the use of AI in endoscopy. However, fewer patients believed that AI could be better than experienced endoscopists, and they felt that endoscopists should remain responsible for decision making. Additionally, most patients believed that endoscopists or hospitals should be liable for any medical malpractice caused by the use of AI. Overall, the survey revealed that patients appreciate the benefits of AI in endoscopy but also recognize the importance of human expertise and accountability. [Extracted from the article]

Introduction: Hepatitis C (HCV) is highly prevalent among people who are incarcerated. HCV treatment-as-prevention was implemented in the SToP-C trial in four correctional centres in New South Wales , Australia to determine whether prison-wide scale up of antiviral treatment was an effective strategy to reduce HCV incidence and prevalence in the prison setting. A qualitative assessment was undertaken with prison-based correctional and health personnel at each of the four prisons to understand operational, sociological, and cultural barriers and enablers to scale up. Informed by a framework for scaling up population health interventions, this analysis examines recommendations by correctional and justice health personnel for HCV treatment-as-prevention scale up in the prison setting.Methods: Correctional (n=24) and justice health (n=17) personnel, including officers, nurses, and senior administrators, participated in interviews across the four prisons where SToP-C was delivered and included two maximum security, one minimum security, and one women's medium/minimum security prisons.Results: Scaling up HCV treatment-as-prevention was contingent on compatibility (including sentence length), efficacy (securely funded positions for dedicated personnel and continuity of care for patients transferring between prisons), stakeholder analysis (generally the whole of prison workforce, particularly custodial officers and senior administrators), reach (reliant on peer and officer champions), and legitimised change (via dedicated officers who could instigate cultural shifts).Conclusion: Achieving scale up of such an intervention should be guided by an understanding of the potential barriers and enablers. This analysis showed key considerations for HCV treatment-as-prevention scale up in correctional centres. [ABSTRACT FROM AUTHOR]

Background: Optimising physical distancing measures has been a critical part of the global response to the spread of COVID-19. Adherence to these recommendations has been poorer than adherence to other key transmission reduction behaviours. The current project aimed to identify psychosocial determinants of adherence to physical distancing, and to determine whether Government of Ireland COVID-19 communications adequately address the determinants. Methods: A nationally representative cross-sectional survey as part of the International COVID-19 Awareness and Responses Evaluation (iCARE) study, a qualitative interview study, and a content analysis of COVID-19 poster communications were conducted to identify psychosocial determinants of adherence and determine the extent to which these were addressed in government communications. Results: The iCARE survey showed adherence to physical distancing measures varies by sociodemographic group (e.g., age, sex, COVID-19 risk category) and beliefs. Poorest adherence was reported by younger people, males, those at lower risk of serious illness from COVID-19, and those who were less concerned about the impact of COVID-19 on public health and the economy. The qualitative interview study revealed maintaining and negotiating close relationships, public physical environments, habituation to threat, risk-taking to maintain wellbeing, and confusion and uncertainty around government guidelines as barriers to physical distancing behaviour. Having a sense of personal responsibility and control over one’s own behaviour was identified as a potential facilitator of adherence to distancing. Content analysis revealed some important gaps, particularly in terms of rationale for specific public health guidelines. Conclusions: Though adherence was high overall, there was variability among sociodemographic groups. Government communications to promote physical distancing could be refined to better address key barriers and facilitators of the behaviour. [ABSTRACT FROM AUTHOR]

Background: The reliability to non‐invasively identify features of inflammatory dermatoses by reflectance confocal microscopy (RCM) remains unknown. Lack of formal training among RCM readers can result in inconsistent assessments, limiting clinical utility. Specific consensus terminology with representative images is necessary to ensure consistent feature‐level interpretation among RCM readers. Objectives: (1) Develop a glossary with representative images of RCM features of cutaneous acute graft‐versus‐host disease (aGVHD) for consistent interpretation among observers, (2) assess the interobserver reproducibility among RCM readers using the glossary, and (3) determine the concordance between RCM and histopathology for aGVHD features. Methods: Through an iterative process of refinement and discussion among five international RCM experts, we developed a glossary with representative images of RCM features of aGVHD. From April to November 2018, patients suspected of aGVHD were imaged with RCM and subsequently biopsied. 17 lesions from 12 patients had clinically and pathologically confirmed cutaneous aGVHD. For each of these lesions, four dermatopathologists and four RCM readers independently evaluated the presence of aGVHD features in scanned histopathology slides and 1.5 × 1.5 mm RCM submosaics at 4 depths (blockstacks) respectively. RCM cases were adjudicated by a fifth RCM expert. Interobserver reproducibility was calculated by mean pairwise difference (U statistic). Concordance between modalities was determined by fraction of assignments with agreement. Results: We present a glossary with representative images of 18 aGVHD features by RCM. The average interobserver reproducibility among RCM readers (75%, confidence interval, CI: 71–79%) did not differ significantly from dermatopathologists (80%, 76–85%). The concordance between RCM and histopathology was 59%. Conclusions: By using the glossary, the interobserver reproducibility among RCM readers was similar to the interobserver reproducibility among dermatopathologists. There was reasonable concordance between RCM and histopathology to visualize aGVHD features. The implementation of RCM can now be advanced in a variety of inflammatory conditions with a validated glossary and representative image set. [ABSTRACT FROM AUTHOR]

This article presents the results of an international survey conducted by the World Endoscopy Organization AI committee on endoscopists' opinions regarding the use of artificial intelligence (AI) in endoscopy. The survey included 465 endoscopists from 83 countries, with a range of backgrounds and experience levels. The majority of participants believed that AI would improve endoscopy quality, efficiency, and patient outcomes. However, there were concerns about financial reimbursement, medical liability, potential de-skilling, and the possibility of unnecessary resections and increased procedure times. Overall, most endoscopists expressed a willingness to use AI when available. [Extracted from the article]

This article explores the impact of artificial intelligence (AI) on the diagnostic confidence of endoscopists assessing videos of Barrett's esophagus (BE). The study involved 22 endoscopists from 12 centers who reviewed standardized endoscopy videos with and without AI. The results showed that the use of AI significantly increased confidence levels for both expert and non-expert endoscopists. Interestingly, non-experts also experienced a significant increase in accuracy when using AI. These findings suggest that AI has the potential to improve diagnostic confidence during endoscopic assessments. [Extracted from the article]

We examine how extended-release buprenorphine depot (BUP-XR) is put to use and made to work in implementation practices, attending to how care practices are challenged and adapted as a long-acting technology is introduced into service in opioid agonist treatment (OAT) in Australia. Our approach is informed by ideas in science and technology studies (STS) emphasising the irreducible entanglement of care practices and technology, and in particular the concept of 'tinkering' as a practice of adaptation. To make our analysis, we draw on qualitative interview accounts (n = 19) of service providers involved in BUP-XR implementation across five sites. Our analysis considers the disruptive novelty of BUP-XR. Tinkering to make a novel technology work in practice slows down the expectation of implementation in relation to transformative innovation, despite the promise of dramatic or rapid change. Tinkering allowed for more open relations, for new care practices that departed from the routine and familiar, opening potential for how BUP-XR could be put to use and made to work in its new situation, and as its situation evolved along-with its implementation. Flexibility and openness of altering relations was, however, at times, held in tension with inflexibility and closure. This analysis identifies a concern for what is made present and what is made absent in the altered care network affected by BUP-XR, with the multiple effects of supervised daily dosing practices thrown into relief as they become absented. Tinkering to implement BUP-XR locally connects with a broader assemblage of trial and movement in the constitution of treatment. The introduction of long-acting technologies prompts new questions about embedded implementation practices, including supervised dosing, urinalysis, the time and place of psychosocial support, and how other social aspects of care might be recalibrated in drug treatment. [ABSTRACT FROM AUTHOR]

The diadematid sea urchin Centrostephanus rodgersii occurs in Australia and New Zealand and has undergone recent southward range extension in Australia as a result of regional warming. Clarifying the population genetic structure of this species across its New Zealand range would allow a better understanding of recent and future mechanisms driving range changes in the species. Here, we use microsatellite DNA data to assess connectivity and genetic structure in 385 individuals from 14 locations across the Australian and New Zealand ranges of the species. We detected substantial genetic differentiation among C. rodgersii populations from Australia and New Zealand. However, the population from Port Stephens (located north of Newcastle), Australia, strongly clustered with New Zealand samples. This suggests that the New Zealand populations recently originated from this area, likely via larval transport in the Tasman Front flow that arises in this region. The weak population genetic structure and relatively low genetic diversity detected in New Zealand (global Fst = 0.0021) relative to Australia (global Fst = 0.0339) is consistent with the former population's inferred history of recent climate-driven expansion. Population-level inbreeding is low in most populations, but were higher in New Zealand (global Fis = 0.0833) than in Australia (global Fis = 0.0202), suggesting that self-recruitment is playing an increasingly important role in the New Zealand region. Our results suggest that C. rodgersii is likely to spread southwards as ocean temperatures increase; therefore, it is crucial that researchers develop a clearer understanding of how New Zealand ecosystems will be reshaped by this species (and others) under climate change. [ABSTRACT FROM AUTHOR]

A chief tool in plant conservation is the augmenting or establishment of threatened plant populations by translocating individuals grown ex-situ. As translocations become an increasingly common practise in conservation and land management, various techniques to increase survival and persistence have become established as standard. Here we use a large historical database of plant translocations to evaluate the evidence for common management techniques to enhance translocation performance. We found that the most important factors associated with maximising size and survival of translocated plant populations were the number of propagules planted, fencing to protect from herbivores, and stimulating recruitment. Factors influencing the probability of recruitment were less certain, however burning and watering increased its likelihood. We also asked how habitat and lifeform influenced translocation performance. Translocations in grassland habitats performed worse than other habitats, and translocations of their predominant lifeform, the perennial grasses, also compared poorly. Our results make a strong case for the utility of a limited number of management interventions, and we highlight where a more explicit focus on experimental data might build our understanding of the factors influencing success in plant translocations. [ABSTRACT FROM AUTHOR]

Although recent regulatory approval of splice-switching oligonucleotides (SSOs) for the treatment of Duchenne muscular dystrophy (DMD) has been an advance for the field, current SSO chemistries have shown limited clinical benefit due to poor pharmacology. There also remains substantial unmet clinical need for approaches that reach cardiac and respiratory muscles, where restoration of dystrophin may be essential to improve survival. To overcome limitations of existing technologies, we engineered stereopure oligonucleotides with phosphorothioate (PS), phosphodiester (PO), and phosphoryl guanidine-containing (PN) backbones. In survival studies, bi-weekly doses of the PS/PO/PN SSO prevented premature death and improved median survival from 49 days to at least 280 days in the double utrophin/dystrophin knockout mouse, a model with an aggressive dystrophic phenotype. These profound survival benefits were achieved at doses anticipated to be clinically relevant. Importantly, the PS/PO/PN SSO increased dystrophin levels across several muscle types (skeletal, respiratory, and cardiac) and improved both respiratory and skeletal muscle function. Treatment also corresponded with decreased serum biomarkers of muscle damage and improved weight gain. These data demonstrate that chemical optimization can profoundly impact oligonucleotide pharmacology and highlight the therapeutic potential of stereopure PN-containing SSOs in DMD. Further, these data help to support the advancement of WVE-N531, an investigational compound currently in clinical testing (NCT04906460) that incorporates this technology, for the treatment of patients with DMD amenable to exon 53 skipping. [ABSTRACT FROM AUTHOR]