Search

We present an algorithm to detect melt onset over Arctic sea ice using high resolution synthetic aperture radar (SAR) images from RADARSAT. The algorithm is based on the temporal evolution of the SAR backscatter coefficient (σ°), using an ice type specific threshold approach that also corrects for incidence angle variation. Using 4457 RADARSAT images, the algorithm was applied over sea ice in the northern Canadian Arctic Archipelago that low spatial resolution microwave sensors have difficulty resolving, thus generating a new time series of melt onset from 1997 to 2014. Over the 1997–2014 period, the mean annual average melt onset date in the northern CAA was on year day 164 (mid–June) with a standard deviation of 4 days. No significant trend for melt onset date was found over the 18-year period. An earlier (later) melt onset was associated with increased (decreased) solar energy absorption ( r = 0.64, significant at 95% confidence) and subsequently associated in lighter (heavier) September sea ice coverage in the northern CAA ( r = 0.62, significant at 95% confidence). RADARSAT estimates of melt onset were found to be in good agreement but more robust compared to passive microwave and scatterometer estimates over the northern CAA. [ABSTRACT FROM AUTHOR]

In 2015, the Resident Education Committee of the North American Society for Pediatric and Adolescent Gynecology published the Long Curriculum in Resident Education to provide educators with a comprehensive document to be used in postgraduate medical education. The original curriculum was designed to meet the resident learning objectives for the Council on Resident Education in Obstetrics and Gynecology, the American Board of Pediatrics, and the Royal College of Physicians and Surgeons of Canada and to provide a more intensive, broader learning experience. The curriculum was updated in 2018. This Committee Document is the third updated version (3.0) of the Long Curriculum in Resident Education. [ABSTRACT FROM AUTHOR]

The aim of this study was to characterize the information needs experienced by adult patients across the continuum of their hematological cancer. Individual semi-structured telephone interviews were conducted with 28 adults with hematological cancer and 18 clinicians recruited from across Canada and analyzed using interpretive description. Distinct information needs were organized across seven points of the cancer continuum: prior to diagnosis, at diagnosis, prior to treatment, during treatment, after treatment, relapse/non-response, and end of life. Patients' information needs reflected a desire to better understand their current physical and psychosocial circumstances, as well as how to make decisions about their treatment, self-management, and health care. The need to receive information in a preparatory way was relevant across all phases of the cancer continuum. Our work contributes an initial approach for providing patient education and counselling for people with hematological cancers, which can be tailored based on individuals' unique characteristics and treatment pathways. Adults with hematological cancers require information to support decision making over the course of their diagnosis, treatment, and survivorship, but can experience information overwhelm. These findings provide an approach for organizing the delivery of information based on different points of need across the cancer continuum. • Adults with hematological cancers have distinct information needs that vary across the cancer continuum. • Patients desire preparatory information to understand expectations and available support across all phases of the continuum. • Our findings guide the delivery of tailored information to hematological cancer patients based on their specific cancer phase. [ABSTRACT FROM AUTHOR]

Background: Treatments for childhood cancer have evolved over the past 50 years, with the goal of maximising the proportion of patients who achieve long-term survival, while minimising the adverse effects of therapy. We aimed to assess incidence patterns of serious chronic health conditions in long-term survivors of childhood cancer across three decades of diagnosis and treatment.Methods: We used data from the Childhood Cancer Survivor Study, a retrospective cohort with longitudinal follow-up of 5-year survivors of common childhood cancers (leukaemia, tumours of the CNS, Hodgkin lymphoma, non-Hodgkin lymphoma, Wilms tumour, neuroblastoma, soft tissue sarcoma, or bone tumours) who were diagnosed before the age of 21 years and from 1970 to 1999 in North America. We examined the cumulative incidence of severe to fatal chronic health conditions occurring up to 20 years post-diagnosis among survivors, compared by diagnosis decade. We used multivariable regression models to estimate hazard ratios per diagnosis decade, and we added treatment variables to assess whether treatment changes attenuated associations between diagnosis decade and chronic disease risk.Findings: Among 23 601 survivors with a median follow-up of 21 years (IQR 15-25), the 20-year cumulative incidence of at least one grade 3-5 chronic condition decreased significantly from 33·2% (95% CI 32·0-34·3) in those diagnosed 1970-79 to 29·3% (28·4-30·2; p<0·0001) in 1980-89, and 27·5% (26·4-28·6; p=0·012 vs 1980-89) in 1990-99. By comparison, the 20-year cumulative incidence of at least one grade 3-5 condition in 5051 siblings was 4·6% (95% CI 3·9-5·2). The 15-year cumulative incidence of at least one grade 3-5 condition was lower for survivors diagnosed 1990-99 compared with those diagnosed 1970-79 for Hodgkin lymphoma (17·7% [95% CI 15·0-20·5] vs 26·4% [23·8-29·1]; p<0·0001), non-Hodgkin lymphoma (16·9% [14·0-19·7] vs 23·8% [19·9-27·7]; p=0.0053), astrocytoma (30·5% [27·8-33·2] vs 47·3% [42·9-51·7]; p<0·0001), Wilms tumour (11·9% [9·5-14·3] vs 17·6% [14·3-20·8]; p=0·034), soft tissue sarcoma (28·3% [23·5-33·1] vs 36·5% [31·5-41·4]; p=0·021), and osteosarcoma (65·6% [60·6-70·6] vs 87·5% [84·1-91·0]; p<0·0001). By contrast, the 15-year cumulative incidence of at least one grade 3-5 condition was higher (1990-99 vs 1970-79) for medulloblastoma or primitive neuroectodermal tumour (58·9% [54·4-63·3] vs 42·9% [34·9-50·9]; p=0·00060), and neuroblastoma (25·0% [21·8-28·2] vs 18·0% [14·5-21·6]; p=0·0045). Results were consistent with changes in treatment as a significant mediator of the association between diagnosis decade and risk of grade 3-5 chronic conditions for astrocytoma (HR per decade without treatment in the model = 0·77, 95% CI 0·64-0·92; HR with treatment in the model=0·89, 95% CI 0·72-1·11; pmediation=0·0085) and Hodgkin lymphoma (HR without treatment=0·75, 95% CI 0·65-0·85; HR with treatment=0·91, 95% CI 0·73-1·12; pmediation=0·024). Temporal decreases in 15-year cumulative incidence comparing survivors diagnosed 1970-79 to survivors diagnosed 1990-99 were noted for endocrinopathies (5·9% [5·3-6·4] vs 2·8% [2·5-3·2]; p<0·0001), subsequent malignant neoplasms (2·7% [2·3-3·1] vs 1·9% [1·6-2·2]; p=0·0033), musculoskeletal conditions (5·8% [5·2-6·4] vs 3·3% [2·9-3·6]; p<0·0001), and gastrointestinal conditions (2·3% [2·0-2·7] vs 1·5% [1·3-1·8]; p=0·00037), while hearing loss increased (3·0% [2·6-3·5] vs 5·7% [5·2-6·1]; p<0·0001).Interpretation: Our results suggest that more recently treated survivors of childhood cancer had improvements in health outcomes, consistent with efforts over the same time period to modify childhood cancer treatment regimens to maximise overall survival, while reducing risk of long-term adverse events. Continuing advances in cancer therapy offer promise of further reducing the risk of long-term adverse events in childhood cancer survivors. However, achieving long-term survival for childhood cancer continues to come at a cost for many survivors, emphasising the importance of long-term follow-up care for this population.Funding: National Cancer Institute and the American Lebanese-Syrian Associated Charities. [ABSTRACT FROM AUTHOR]

Sulphide inclusions are common features of natural diamonds. They can provide an insight into the nature of diamond-forming reactions and are especially important for Re–Os dating of diamond formation. A discrete molybdenite (MoS 2 ) phase has been identified for the first time by Raman spectroscopy in 73 out of 80 syngenetic sulphide inclusions in 7 eclogitic diamonds from the Mir kimberlite (Yakutia, Russia). The sulphide inclusions were chemically and texturally characterised by electron probe microanalyses (EPMA), focused ion-beam scanning electron microscopy (FIB-SEM) and synchrotron-based X-ray tomographic microscopy (SXRTM). Our observations suggest the molybdenite has unmixed from an original sulphide melt or monosulphide solid solution. It occurs as sub-micron sized grains, commonly in association with the chalcopyrite rims of the inclusions and sometimes, within surrounding decompression cracks. Molybdenite has also been identified by Raman spectroscopy in at least 50% of sulphide inclusions in preliminary studies of eclogitic diamonds from Argyle (NW Australia), Orapa, Letlhakane, Damtshaa (Botswana) and Dachine (French Guiana), and peridotitic diamond-hosted inclusions from Udachnaya (Yakutia, Russia) and Murowa (Zimbabwe). We have modelled the effects that different amounts of Re loss – through its segregation into an unrecovered molybdenite phase – could have on the radiometric ages of diamonds dated using the Re–Os system. In general Re loss through this process will lead to isochron ages older than the true age, and variable degrees of Re loss will lead to increased scatter around the apparent isochron. For model age calculations, the effects would depend on the 187 Re/ 188 Os ratio of the inclusions (if their compositions evolved above or below that of the chondritic mantle evolution curve) but Re loss could generate unrealistically old or future ages, particularly in eclogitic inclusions. [ABSTRACT FROM AUTHOR]