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Catheter ablation is a safe and effective therapy for the treatment of supraventricular tachycardia in children. Current improvements in technology have allowed progressive reduction in radiation exposure associated with the procedure. To assess the impact of three-dimensional mapping, we compared acute procedural results collected from the Catheter Ablation with Reduction or Elimination of Fluoroscopy registry to published results from the Prospective Assessment after Pediatric Cardiac Ablation study.
Methods:
Inclusion and exclusion criteria from the Prospective Assessment after Pediatric Cardiac Ablation study were used as guidelines to select patient data from the Catheter Ablation with Reduction or Elimination of Fluoroscopy registry to compare acute procedural outcomes between cohorts. Outcomes assessed include procedural and fluoroscopy exposure times, success rates of procedure, and complications.
Results:
In 786 ablation procedures, targeting 498 accessory pathways and 288 atrioventricular nodal reentrant tachycardia substrates, average procedural time (156.5 versus 206.7 minutes, p < 0.01), and fluoroscopy time (1.2 versus 38.3 minutes, p < 0.01) were significantly shorter in the study group. Success rates for the various substrates were similar except for manifest accessory pathways which had a significantly higher success rate in the study group (96.4% versus 93.0%, p < 0.01). Major complication rates were significantly lower in the study group (0.3% versus 1.6%, p < 0.01).
Conclusions:
In a large, multicentre study, three-dimensional systems show favourable improvements in clinical outcomes in children undergoing catheter ablation of supraventricular tachycardia compared to the traditional fluoroscopic approach. Further improvements are anticipated as technology advances.
To assess the relationship between food insecurity, sleep quality, and days with mental and physical health issues among college students.
Design:
An online survey was administered. Food insecurity was assessed using the 10-item Adult Food Security Survey Module. Sleep was measured using the 19-item Pittsburgh Sleep Quality Index (PSQI). Mental health and physical health were measured using three items from the Healthy Days Core Module. Multivariate logistic regression was conducted to assess the relationship between food insecurity, sleep quality, and days with poor mental and physical health.
Setting:
Twenty-two higher education institutions.
Participants:
College students (n=17,686) enrolled at one of 22 participating universities.
Results:
Compared to food secure students, those classified as food insecure (43.4%) had higher PSQI scores indicating poorer sleep quality (p<.0001) and reported more days with poor mental (p<.0001) and physical (p<.0001) health as well as days when mental and physical health prevented them from completing daily activities (p<.0001). Food insecure students had higher adjusted odds of having poor sleep quality (adjusted odds ratio [AOR]:1.13, 95% confidence interval [CI]: 1.12-1.14), days with poor physical health (AOR: 1.01, 95% CI: 1.01-1.02), days with poor mental health (AOR: 1.03, 95% CI: 1.02-1.03), and days when poor mental or physical health prevented them from completing daily activities (AOR: 1.03, 95% CI: 1.02-1.04).
Conclusions:
College students report high food insecurity which is associated with poor mental and physical health and sleep quality. Multi-level policy changes and campus wellness programs are needed to prevent food insecurity and improve student health-related outcomes.
Large dams are emerging drivers of landscape-scale habitat fragmentation, causing extensive flooding and transforming hilltops into islands. Environmental Impact Assessments (EIAs; the process to assess and account for impacts of development) do not explicitly consider reservoir islands in calculations of habitat impacted by dam construction. Reservoir islands maintain relict biological communities from the previously continuous habitat. Relict communities are subject to an extinction debt whereby species are lost over time. We demonstrate how estimating the ‘conservation value’ of islands (CV; the proportion of relict continuous habitat [forest] species on islands) using relict species–area relationships (RSARs), can be used in an area-of-impact correction tool to account for insular habitats in EIAs. We used data from eight taxonomic groups within the Balbina Hydroelectric Reservoir (BHR) archipelago in Brazilian Amazonia. We found ca. 72,000 ha of insular habitat had reduced CV, equating to 60% of aggregate island area, and that an additional 24% of the ca. 300,000 ha BHR water surface area should be included in area assessments for impacted terrestrial habitat. Where reservoir island creation is unavoidable, using RSARs to assess the CV of islands enables more accurate and dynamic assessment of the ecological impacts of dam construction.
Finding less complicated coils that have adequately low field errors is a crucial step in stellarator development. One coil metric that is of high importance is the maximum curvature of the coil centreline, or coil single filament. Conductors cannot be bent below some threshold minimum radius of curvature. High coil curvatures can cause strains to exceed acceptable levels, especially in superconducting coils. We investigate three ways to optimize coil curvature and find that applying penalty functions to the coil curvature solves for coils that have a constrained maximum curvature and low field error. Penalty functions are implemented in FOCUS and coil solutions optimized for an HSX-like ‘plasma boundary’ are presented.
In this paper, we describe the system design and capabilities of the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope at the conclusion of its construction project and commencement of science operations. ASKAP is one of the first radio telescopes to deploy phased array feed (PAF) technology on a large scale, giving it an instantaneous field of view that covers $31\,\textrm{deg}^{2}$ at $800\,\textrm{MHz}$. As a two-dimensional array of 36$\times$12 m antennas, with baselines ranging from 22 m to 6 km, ASKAP also has excellent snapshot imaging capability and 10 arcsec resolution. This, combined with 288 MHz of instantaneous bandwidth and a unique third axis of rotation on each antenna, gives ASKAP the capability to create high dynamic range images of large sky areas very quickly. It is an excellent telescope for surveys between 700 and $1800\,\textrm{MHz}$ and is expected to facilitate great advances in our understanding of galaxy formation, cosmology, and radio transients while opening new parameter space for discovery of the unknown.
This SHEA white paper identifies knowledge gaps and challenges in healthcare epidemiology research related to COVID-19 with a focus on core principles of healthcare epidemiology. These gaps, revealed during the worst phases of the COVID-19 pandemic, are described in 10 sections: epidemiology, outbreak investigation, surveillance, isolation precaution practices, personal protective equipment (PPE), environmental contamination and disinfection, drug and supply shortages, antimicrobial stewardship, healthcare personnel (HCP) occupational safety, and return to work policies. Each section highlights three critical healthcare epidemiology research questions with detailed description provided in supplemental materials. This research agenda calls for translational studies from laboratory-based basic science research to well-designed, large-scale studies and health outcomes research. Research gaps and challenges related to nursing homes and social disparities are included. Collaborations across various disciplines, expertise and across diverse geographic locations will be critical.
To identify attention profiles at 7 and 13 years, and transitions in attention profiles over time in children born very preterm (VP; <30 weeks’ gestation) and full term (FT), and examine predictors of attention profiles and transitions.
Methods:
Participants were 167 VP and 60 FT children, evaluated on profiles across five attention domains (selective, shifting and divided attention, processing speed, and behavioral attention) at 7 and 13 years using latent profile analyses. Transitions in profiles were assessed with contingency tables. For VP children, biological and social risk factors were tested as predictors with a multinomial logistic regression.
Results:
At 7 and 13 years, three distinct profiles of attentional functioning were identified. VP children were 2–3 times more likely to show poorer attention profiles compared with FT children. Transition patterns between 7 and 13 years were stable average, stable low, improving, and declining attention. VP children were two times less likely to have a stable average attention pattern and three times more likely to have stable low or improving attention patterns compared with FT children. Groups did not differ in declining attention patterns. For VP children, brain abnormalities on neonatal MRI and greater social risk at 7 years predicted stable low or changing attention patterns over time.
Conclusions:
VP children show greater variability in attention profiles and transition patterns than FT children, with almost half of the VP children showing adverse attention patterns over time. Early brain pathology and social environment are markers for attentional functioning.
We have found a class of circular radio objects in the Evolutionary Map of the Universe Pilot Survey, using the Australian Square Kilometre Array Pathfinder telescope. The objects appear in radio images as circular edge-brightened discs, about one arcmin diameter, that are unlike other objects previously reported in the literature. We explore several possible mechanisms that might cause these objects, but none seems to be a compelling explanation.
We explore marine reservoir effects (MREs) in seal bones from the northern Bering and Chukchi Seas regions. Ringed and bearded seals have served as dietary staples in human populations along the coasts of Arctic northeast Asia and North America for several millennia. Radiocarbon (14C) dates on seal bones and terrestrial materials (caribou, plants seeds, wood, and wood charcoal) were compared from archaeological sites in the Bering Strait region of northwestern Alaska to assess MREs in these sea mammals over time. We also compared these results to 14C dates on modern seal specimens collected in AD 1932 and 1946 from the Bering Sea region. Our paired archaeological samples were recovered from late Holocene archaeological features, including floors from dwellings and cache pits, that date between 1600 and 130 cal BP. 14C dates on seal bones from the northern Bering and Chukchi Seas show differences [R(t)] of 800 ± 140 years from to their terrestrial counterparts, and deviations of 404 ± 112 years (ΔR) from the marine calibration curve.
Subanesthetic ketamine infusion therapy can produce fast-acting antidepressant effects in patients with major depression. How single and repeated ketamine treatment modulates the whole-brain functional connectome to affect clinical outcomes remains uncharacterized.
Methods
Data-driven whole brain functional connectivity (FC) analysis was used to identify the functional connections modified by ketamine treatment in patients with major depressive disorder (MDD). MDD patients (N = 61, mean age = 38, 19 women) completed baseline resting-state (RS) functional magnetic resonance imaging and depression symptom scales. Of these patients, n = 48 and n = 51, completed the same assessments 24 h after receiving one and four 0.5 mg/kg intravenous ketamine infusions. Healthy controls (HC) (n = 40, 24 women) completed baseline assessments with no intervention. Analysis of RS FC addressed effects of diagnosis, time, and remitter status.
Results
Significant differences (p < 0.05, corrected) in RS FC were observed between HC and MDD at baseline in the somatomotor network and between association and default mode networks. These disruptions in FC in MDD patients trended toward control patterns with ketamine treatment. Furthermore, following serial ketamine infusions, significant decreases in FC were observed between the cerebellum and salience network (SN) (p < 0.05, corrected). Patient remitters showed increased FC between the cerebellum and the striatum prior to treatment that decreased following treatment, whereas non-remitters showed the opposite pattern.
Conclusion
Results support that ketamine treatment leads to neurofunctional plasticity between distinct neural networks that are shown as disrupted in MDD patients. Cortico-striatal-cerebellar loops that encompass the SN could be a potential biomarker for ketamine treatment.
The Rapid ASKAP Continuum Survey (RACS) is the first large-area survey to be conducted with the full 36-antenna Australian Square Kilometre Array Pathfinder (ASKAP) telescope. RACS will provide a shallow model of the ASKAP sky that will aid the calibration of future deep ASKAP surveys. RACS will cover the whole sky visible from the ASKAP site in Western Australia and will cover the full ASKAP band of 700–1800 MHz. The RACS images are generally deeper than the existing NRAO VLA Sky Survey and Sydney University Molonglo Sky Survey radio surveys and have better spatial resolution. All RACS survey products will be public, including radio images (with
$\sim$
15 arcsec resolution) and catalogues of about three million source components with spectral index and polarisation information. In this paper, we present a description of the RACS survey and the first data release of 903 images covering the sky south of declination
$+41^\circ$
made over a 288-MHz band centred at 887.5 MHz.
The objective of the current study was to identify challenges of making and sustaining healthy lifestyle changes for families with children/adolescents affected by obesity, who were referred to a multicomponent healthy lifestyle assessment and intervention programme in Aotearoa/New Zealand (NZ).
Design:
Secondary qualitative analysis of semi-structured interviews.
Setting:
Taranaki region of Aotearoa/NZ.
Participants:
Thirty-eight interviews with parents/caregivers (n 42) of children/adolescents who had previously been referred to a family-focused multidisciplinary programme for childhood obesity intervention, who identified challenges of making healthy lifestyle changes. Participants had varying levels of engagement, including those who declined contact after their referral.
Results:
Participant-identified challenges included financial cost, impact of the food environment, time pressures, stress, maintaining consistency across households, independence in adolescence, concern for mental health and frustration when not seeing changes in weight status.
Conclusions:
Participants recognised a range of factors that contributed towards their ability to make and sustain change, including factors at the wider socio-environmental level beyond their immediate control. Even with the support of a multidisciplinary healthy lifestyle programme, participants found it difficult to make sustained changes within an obesogenic environment. Healthy lifestyle intervention programmes and families’ abilities to make and sustain changes require alignment of prevention efforts, focusing on policy changes to improve the food environment and eliminate structural inequities.
To evaluate whether vanA rectal screening for vancomycin-resistant Enterococcus (VRE) predicts vancomycin resistance for patients with enterococcal bloodstream infection (BSI).
Design:
A retrospective cohort study.
Setting:
Large academic medical center.
Methods:
The predictive performance of a vanA rectal swab was evaluated in 161 critically ill adults with an enterococcal BSI from January 1, 2007, to September 1, 2014, and who had a vanA rectal swab screening obtained within 14 days prior to blood culture.
Results:
Of the patients meeting inclusion criteria, 83 (51.6%) were vanA swab positive. Rectal-swab–positive patients were more likely to be younger, to be immunocompromised, to have an indwelling central vascular catheter, and to have a history of MDR bacteria. The vanA rectal swab had sensitivity and negative predictive values of 83.6% and 85.9%, respectively, and specificity and positive predictive values of 71.3% and 67.5%, respectively, for predicting a vancomycin-resistant enterococcal BSI in critically ill adults.
Conclusions:
VanA rectal swabs may be useful for antimicrobial stewardship at institutions with VRE screening already in place for infection control purposes. A higher PPV would be warranted to implement a universal vanA screen on all ICU patients.
To successfully reduce overall invasive plant cover over time, an effective treatment plan must be established such that mortality exceeds new colonization and resprouting growth rates. However, few evaluations of the effects of long-term, consistent treatment at different intervals exist. We report the effects of treatment intensity on Old World climbing fern [Lygodium microphyllum (Cav.) R. Br.], Brazilian pepper (Schinus terebinthifolia Raddi), and punktree [Melaleuca quinquenervia (Cav.) S. F. Blake] as part of a large restoration project that has been underway for 6 yr in Telegraph Swamp at Babcock Ranch Preserve, a 27,520-hectare (68,000-acre) conservation area in Florida, USA. We found that at the end of the 6-yr period, for all three species, average live cover did not exceed 5% across all transects. In addition, dead foliar cover was higher than live cover for all three invasive plants, indicating progress toward restoration goals. We also found that percent live cover of L. microphyllum was significantly reduced only after four or more treatments were applied during the 6-yr period, as opposed to when three or fewer treatments were applied. Reductions in percent cover of live foliage were apparent only when the treatments were applied more often than biennially, as opposed to less often than biennially. Additionally, we found higher L. microphyllum cover in clear-cut and replanted cypress stands than in natural stands. Based on these findings, we conclude that treatments applied four or more times, or more often than biennially, were more effective at significantly reducing advanced invasions of L. microphyllum, S. terebinthifolia, and M. quinquenervia, especially where previous management activities or their effects may have increased the cover of invasive plants.
We performed a cross-sectional survey of infection preventionists in 60 US community hospitals between April 22 and May 8, 2020. Several differences in hospital preparedness for SARS-CoV-2 emerged with respect to personal protective equipment conservation strategies, protocols related to testing, universal masking, and restarting elective procedures.
A new optimized quasi-helically symmetric configuration is described that has the desirable properties of improved energetic particle confinement, reduced turbulent transport by three-dimensional shaping and non-resonant divertor capabilities. The configuration presented in this paper is explicitly optimized for quasi-helical symmetry, energetic particle confinement, neoclassical confinement and stability near the axis. Post optimization, the configuration was evaluated for its performance with regard to energetic particle transport, ideal magnetohydrodynamic stability at various values of plasma pressure and ion temperature gradient instability induced turbulent transport. The effects of discrete coils on various confinement figures of merit, including energetic particle confinement, are determined by generating single-filament coils for the configuration. Preliminary divertor analysis shows that coils can be created that do not interfere with expansion of the vessel volume near the regions of outgoing heat flux, thus demonstrating the possibility of operating a non-resonant divertor.