The SNO+ collaboration reports its first spectral analysis of long-baseline
reactor antineutrino oscillation using 114 tonne-years of data. Fitting the
neutrino oscillation probability to the ...observed energy spectrum yields
constraints on the neutrino mass-squared difference $\Delta m^2_{21}$. In the
ranges allowed by previous measurements, the best-fit $\Delta m^2_{21}$ is
(8.85$^{+1.10}_{-1.33}$) $\times$ 10$^{-5}$ eV$^2$. This measurement is
continuing in the next phases of SNO+ and is expected to surpass the present
global precision on $\Delta m^2_{21}$ with about three years of data.
Icebergs in proglacial fjords serve as pupping, resting and molting habitat for some of the largest seasonal aggregations of harbor seals (Phoca vitulina richardii) in Alaska. One of the largest ...aggregations in Southeast Alaska occurs in Johns Hopkins Inlet, Glacier Bay National Park, where up to 2000 seals use icebergs produced by Johns Hopkins Glacier. Like other advancing tidewater glaciers, the advance of Johns Hopkins Glacier over the past century has been facilitated by the growth and continual redistribution of a submarine end moraine, which has limited mass losses from iceberg calving and submarine melting and enabled glacier thickening by providing flow resistance. A 15-year record of aerial surveys reveals (i) a decline in iceberg concentrations concurrent with moraine growth and (ii) that the iceberg size distributions can be approximated as power law distributions, with relatively little variability and no clear trends in the power law exponent despite large changes in ice fluxes over seasonal and interannual timescales. Together, these observations suggest that sustained tidewater glacier advance should typically be associated with reductions in the number of large, habitable icebergs, which may have implications for harbor seals relying on iceberg habitat for critical life-history events.
Abstract
While large-scale observations of intensified fracture and rifting can be observed through remote-sensing observations, understanding crevasse initiation may best be achieved with ...small-scale observations in which crevasses can be directly observed. Here we investigate the kinematic drivers of crevasse initiation in the McMurdo Shear Zone (MSZ), Antarctica. We delineated 420 crevasses from ~95 km of 400 MHz frequency ground-penetrating radar data and compared these data with kinematic outputs derived from remotely-sensed ice surface velocities to develop a statistical method to estimate crevasse initiation threshold strain rate values. We found the MSZ to be dominated by simple shear and that surface shear strain rates proved best for predicting crevasse features, with regions of higher shear strain rate more likely to have a greater number of crevasses. In the surveyed portion of our study region, values of shear strain rate and vorticity rate derived from the MEaSUREs2 velocity dataset range between 0.005–0.020 and 0.006–0.022 a
−1
, respectively, with crevasses located at ≥0.011 and ≥0.013 a
−1
. While threshold values from this study cannot be directly applied to other glacial environments, the method described here should allow for the study of shear margin evolution and assessment of localized damage and weakening processes in other locations where in situ data are available.
Current therapies for treating cervical dysplasia are often inaccessible in low and middle-income countries (LMICs), highlighting the need for novel low-cost therapies that can be delivered at the ...point of care. Ethanol ablation is a low-cost therapy designed to treat locoregional cancers, which we augmented into an ethyl cellulose (EC)-ethanol gel formulation to enhance its efficacy. Here, we evaluated whether EC-ethanol ablation is able to safely achieve an ablation zone comparable to thermocoagulation, a commonly used therapy for cervical dysplasia. The study was performed in 20 female Yorkshire pigs treated with either a single 500 µL injection of EC-ethanol into the 12 o'clock position of the cervix or a single application of thermocoagulation at 100 °C for 20 s. The average temperature, heart rate, respiratory rate, and blood oxygen remained within normal ranges throughout the EC-ethanol procedure and were similar to the thermocoagulation group. No major side effects were observed. The reproductive tracts were excised after 24 h to examine ablation zones. Comparable depths of necrosis were seen for EC-ethanol (18.6 ± 1.6 mm) and thermocoagulation (19.7 ± 4.1 mm). The volumes of necrosis induced by a single injection of EC-ethanol (626.2 ± 122.8 µL) were comparable to the necrotic volumes induced by thermocoagulation in the top half of the cervices (664.6 ± 168.5 µL). This suggests that two EC-ethanol injections could be performed (e.g., at the 12 and 6 o'clock positions) to achieve comparable total necrotic volumes to thermocoagulation and safely and effectively treat women with cervical dysplasia in LMICs. This is the first study to systematically evaluate EC-ethanol ablation in a large animal model and compare its safety and efficacy to thermocoagulation, a commonly used ablative therapy for cervical dysplasia.
Background Homelessness has been associated with multiple detrimental health outcomes across observational studies. However, relatively few randomized controlled trials (RCTs) have been conducted on ...people who experience homelessness (PEH). Thus, this umbrella review ranked the credibility of evidence derived from systematic reviews (SRs) and meta-analyses (MAs) of observational studies investigating the associations between homelessness and any health outcome as well as RCTs targeting health needs in this population. Methods Several databases were systematically searched from inception through April 28, 2021. Any SR and/or MA reporting quantitative data and providing a control group were eligible for inclusion. The credibility of the evidence derived from observational studies was appraised by considering the significance level of the association and the largest study, the degree of heterogeneity, the presence of small-study effects as well as excess significance bias. The credibility of evidence was then ranked in five classes. For SRs and/or MAs of RCTs, we considered the level of significance and whether the prediction interval crossed the null. The AMSTAR-2 and AMSTAR-plus instruments were adopted to further assess the methodological quality of SRs and/or MAs. The Newcastle-Ottawa Scale (NOS) was employed to further appraise the methodological quality of prospective cohort studies only; a sensitivity analysis limited to higher quality studies was conducted. Results Out of 1549 references, 8 MAs and 2 SRs were included. Among those considering observational studies, 23 unique associations were appraised. Twelve of them were statistically significant at the pless than or equai to0.005 level. Included cases had worst health-related outcomes than controls, but only two associations reached a priori-defined criteria for convincing (class I) evidence namely hospitalization due to any cause among PEH diagnosed with HIV infection, and the occurrence of falls within the past year among PEH. According to the AMSTAR-2 instrument, the methodological quality of all included SRs and/or MAs was "critically low." Interventional studies were scant. Conclusion While homelessness has been repeatedly associated with detrimental health outcomes, only two associations met the criteria for convincing evidence. Furthermore, few RCTs were appraised by SRs and/or MAs. Our umbrella review also highlights the need to standardize definitions of homelessness to be incorporated by forthcoming studies to improve the external validity of the findings in this vulnerable population. Keywords: Homeless, Health outcomes, Severe mental illness, Umbrella review
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Background
Pregnancy is a vulnerable time where the physical and social stress of the COVID-19 pandemic affects psychological health, including postpartum depression (PPD). This study is ...designed to estimate the prevalence and correlates of PPD and risk of suicidality among individuals who gave birth during the COVID-19 pandemic.
Methods
We surveyed individuals who gave birth at The Ottawa Hospital and were ≥ 20 days postpartum, between March 17 and June 16, 2020. A PPD screen consisted of a score ≥ 13 using the Edinburgh Postnatal Depression Scale. A score of 1, 2, or 3 on item 10 (“The thought of harming myself has occurred to me”) indicates risk of suicidality. If a participant scores greater than ≥ 13 or ≥ 1 on item 10 they were flagged for PPD, the Principal Investigator (DEC) was notified within 24 h of survey completion for a chart review and to assure follow-up. Modified Poisson multivariable regression models were used to identify factors associated with PPD and risk of suicidality using adjusted risk ratios (aRR) and 95% confidence intervals (CI).
Results
Of the 216 respondents, 64 (30%) screened positive for PPD and 17 (8%) screened positive for risk of suicidality. The maternal median age of the total sample was 33 years (IQR: 30–36) and the infant median age at the time of the survey was 76 days (IQR: 66–90). Most participants reported some form of positive coping strategies during the pandemic (97%) (e.g. connecting with friends and family, exercising, getting professional help) and 139 (64%) reported negative coping patterns (e.g. over/under eating, sleep problems). In total, 47 (22%) had pre-pregnancy anxiety and/or depression. Negative coping (aRR:2.90, 95% CI: 1.56–5.37) and pre-existing anxiety/depression (aRR:2.03, 95% CI:1.32–3.11) were associated with PPD. Pre-existing anxiety/depression (aRR:3.16, 95% CI:1.28–7.81) was associated with risk of suicidality.
Conclusions
Almost a third of participants in this study screened positive for PPD and 8% for risk of suicidality. Mental health screening and techniques to foster positive coping skills/strategies are important areas to optimize postpartum mental health.
IntroductionPeople with serious mental illness (SMI) have poor health outcomes, in part because of inequitable access to quality health services. Primary care is well suited to coordinate and manage ...care for this population; however, providers may feel ill-equipped to do so and patients may not have the support and resources required to coordinate their care. We lack a strong understanding of prevention and management of chronic disease in primary care among people with SMI as well as the context-specific barriers that exist at the patient, provider and system levels. This mixed methods study will answer three research questions: (1) How do primary care services received by people living with SMI differ from those received by the general population? (2) What are the experiences of people with SMI in accessing and receiving chronic disease prevention and management in primary care? (3) What are the experiences of primary care providers in caring for individuals with SMI?Methods and analysisWe will conduct a concurrent mixed methods study in Ontario and British Columbia, Canada, including quantitative analyses of linked administrative data and in-depth qualitative interviews with people living with SMI and primary care providers. By comparing across two provinces, each with varying degrees of mental health service investment and different primary care models, results will shed light on individual and system-level factors that facilitate or impede quality preventive and chronic disease care for people with SMI in the primary care setting.Ethics and disseminationThis study was approved by the University of Ottawa Research Ethics Board and partner institutions. An integrated knowledge translation approach brings together researchers, providers, policymakers, decision-makers, patient and caregiver partners and knowledge users. Working with this team, we will develop policy-relevant recommendations for improvements to primary care systems that will better support providers and reduce health inequities.
Abstract
Background
As of May 2022, Ontario has seen more than 1.3 million cases of COVID-19. While the majority of individuals will recover from infection within 4 weeks, a significant subset ...experience persistent and often debilitating symptoms, known as “post-COVID syndrome” or “Long COVID.” Those with Long COVID experience a wide array of symptoms, with variable severity, including fatigue, cognitive impairment, and shortness of breath. Further, the prevalence and duration of Long COVID is not clear, nor is there evidence on the best course of rehabilitation for individuals to return to their desired level of function. Previous work with chronic conditions has suggested that the addition of electronic case management (ECM) may help to improve outcomes. These platforms provide enhanced connection with care providers, detailed symptom tracking and goal setting, and access to relevant resources. In this study, our primary aim is to determine if the addition of ECM with health coaching improves Long COVID outcomes at 3 months compared to health coaching alone.
Methods
The trial is an open-label, single-site, randomized controlled trial of ECM with health coaching (ECM+) compared to health coaching alone (HC). Both groups will continue to receive usual care. Participants will be randomized equally to receive health coaching (± ECM) for a period of 8 weeks and a 12-week follow-up. Our primary outcome is the WHO Disability Assessment Scale (WHODAS), 36-item self-report total score. Participants will also complete measures of cognition, fatigue, breathlessness, and mental health. Participants and care providers will be asked to complete a brief qualitative interview at the end of the study to evaluate acceptability and implementation of the intervention.
Discussion
There is currently little evidence about the optimal treatment of Long COVID patients or the use of digital health platforms in this population. The results of this trial could result in rapid, scalable, and personalized care for people with Long COVID which will decrease morbidity after an acute infection. Results from this study will also inform decision making in Long COVID and treatment guidelines at provincial and national levels.
Trial registration
ClinicalTrials.gov NCT05019963. Registered on 25 August 2021.
The McMurdo shear zone (MSZ) is strip of heavily crevassed ice oriented in the south-north direction and moving northward. Previous airborne surveys revealed a chaotic crevasse structure superimposed ...on a set of expected crevasse orientations at 45 degrees to the south-north flow (due to shear stress mechanisms). The dynamics that produced this chaotic structure are poorly understood. Our purpose is to present our field methodology and provide field data that will enable validation of models of the MSZ evolution, and here, we present a method for deriving a local velocity field from ground penetrating radar (GPR) data towards that end. Maps of near-surface crevasses were derived from two annual GPR surveys of a 28 km2 region of the MSZ using Eulerian sampling. Our robot-towed and GPS navigated GPR enabled a dense survey grid, with transects of the shear zone at 50 m spacing. Each survey comprised multiple crossings of long (> 1 km) crevasses that appear in echelon on the western and eastern boundaries of the shear zone, as well as two or more crossings of shorter crevasses in the more chaotic zone between the western and eastern boundaries. From these maps, we derived a local velocity field based on the year-to-year movement of the same crevasses. Our velocity field varies significantly from fields previously established using remote sensing and provides more detail than one concurrently derived from a 29-station GPS network. Rather than a simple velocity gradient expected for crevasses oriented approximately 45 degrees to flow direction, we find constant velocity contours oriented diagonally across the shear zone with a wavy fine structure. Although our survey is based on near-surface crevasses, similar crevassing found in marine ice at 160 m depth leads us to conclude that this surface velocity field may hold through the body of meteoric and marine ice. Our success with robot-towed GPR with GPS navigation suggests we may greatly increase our survey areas.
•A methodology for acquiring ground-penetrating radar (GPR) data using and autonomous robot.•A methodology for and results of using robot-acquired GPR data to measure local variation in the velocity field of a heavily-crevassed shear zone.•Results of processing robot-acquired GPR data to identify coeval surface and marine ice crevassing.
As ice shelves are floating and lack resistive stress at their base, resistance to flow is accommodated along their lateral margins and various pinning points such as ice rises and nunataks. As such, ...ice shelf shear margins and their strength through time remain a critical control on ice shelf stability. Specifically, lateral shear zone destabilization is an important precursor to ice shelf collapse. In this thesis I utilize in-situ, remote sensing, and numerical modeling techniques in order to characterize the flow field and geometry of the western lateral margin of the Ross Ice Shelf as well as a region upstream of the grounding line. I first develop a method to investigate the kinematic drivers of crevasse initiation in the McMurdo Shear Zone, Antarctica through the delineation of crevasse features from ground penetrating radar observations and comparison with kinematic outputs derived from remotely-sensed ice surface velocities. I then use spatial patterns in crevasse attributes to make inferences on crevasse history and discuss implications on the current and future stability of the shear margin. Next, I estimate ice thickness within this shear margin from a combination of mid-frequency ground penetrating radar observations and Digital Elevation Models and assess the sensitivity of Ross Ice Shelf stress balance to uncertainties in ice thickness datasets within this region through numerical modeling techniques. My results suggest that previous modeling frameworks have overestimated the sensitivity of the region to melting. Finally, I perform a transient streamline analysis of a region of upstream grounded ice known as the Whillans and Ice Stream and characterize the short-term velocity fluctuations within its slowdown evolution using available remotely-sensed velocity datasets between 1997 and 2016. I incorporate these observations of velocity fluctuations as well as mass changes into a transient finite element modeling solution of ice flow. Through inversion techniques, I estimate annual changes in basal shear stress in order to force a 100-year transient model of ice slowdown for the Whillans Ice Stream and discuss the possible mechanisms that could be driving slowdown fluctuations on annual timescales such as lake drainage events, basal freeze-on and till weakening mechanisms, as well as changes to downstream boundary conditions.
PDF
