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The Greenland Ice Sheet (GIS) is losing mass at a high rate1. Given the short-term nature of the observational record, it is difficult to assess the historical importance of this mass-loss trend. Unlike records of greenhouse gas concentrations and global temperature, in which observations have been merged with palaeoclimate datasets, there are no comparably long records for rates of GIS mass change. Here we reveal unprecedented mass loss from the GIS this century, by placing contemporary and future rates of GIS mass loss within the context of the natural variability over the past 12,000 years. We force a high-resolution ice-sheet model with an ensemble of climate histories constrained by ice-core data2. Our simulation domain covers southwestern Greenland, the mass change of which is dominated by surface mass balance. The results agree favourably with an independent chronology of the history of the GIS margin3,4. The largest pre-industrial rates of mass loss (up to 6,000 billion tonnes per century) occurred in the early Holocene, and were similar to the contemporary (ad 2000–2018) rate of around 6,100 billion tonnes per century5. Simulations of future mass loss from southwestern GIS, based on Representative Concentration Pathway (RCP) scenarios corresponding to low (RCP2.6) and high (RCP8.5) greenhouse gas concentration trajectories6, predict mass loss of between 8,800 and 35,900 billion tonnes over the twenty-first century. These rates of GIS mass loss exceed the maximum rates over the past 12,000 years. Because rates of mass loss from the southwestern GIS scale linearly5 with the GIS as a whole, our results indicate, with high confidence, that the rate of mass loss from the GIS will exceed Holocene rates this century. Rates of ice-mass loss from southwestern Greenland this century will exceed the maximum rate over the past 12,000 years, and would not be the result of natural variation.

Guidelines recommend individualized breast cancer screening and prevention interventions for women in their 40s. Yet, few primary care clinicians assess breast cancer risk.Pretest-Posttest trial.Women aged 40-49 years were recruited from one large Boston-based academic primary care practice between July 2017 and April 2019.Participants completed a pretest, received a personalized breast cancer risk report, saw their primary care clinician, and completed a posttest.Using mixed effects models, changes in screening intentions (0-100 scale [0=will not screen to 100=will screen]), mammography knowledge, decisional conflict, and receipt of screening were examined. Analyses were conducted from June 2019 to February 2020.Patient (n=337) mean age was 44.1 (SD=2.9) years, 61.4% were non-Hispanic white, and 76.6% were college graduates; 306 (90.5%) completed follow-up (203 with 5-year breast cancer risk1.1%). Screening intentions declined from pre- to post-visit (79.3 to 68.0, p0.0001), especially for women with 5-year risk1.1% (77.2 to 63.3, p0.0001), but still favored screening. In the 2 years prior, 37.6% had screening mammography compared with 41.8% over a mean 16 months follow-up (p=0.17). Mammography knowledge increased and decisional conflict declined. Eleven (3.3%) women met criteria for breast cancer prevention medications (ten discussed medications with their clinicians), 22 (6.5%) for MRI (19 discussed MRI with their clinician), and 67 (19.8%) for genetic counseling (47 discussed with the clinician).Receipt of a personalized breast cancer report was associated with women in their 40s making more-informed and less-conflicted mammography screening decisions and with high-risk women discussing breast cancer prevention interventions with clinicians.This study is registered at www.clinicaltrials.govNCT03180086.

Precision medicine (PM) refers to the use of available genomic information from an individual patient to select the most appropriate therapy for a disease. In this paper, we have developed a mechan...

Stable isotopes of oxygen (δ18O) and hydrogen (δ2H) in precipitation are widely employed tracers of the global hydrologic cycle, and are frequently inferred from lake-water-derived proxies in sediments of high-latitude lakes. Lake-water isotope proxies archive precipitation δ18O and δ2H values, modulated by lake hydrological processes, which may be functionally classified into processes that affect source water isotope values (i.e. inflow δ18O and δ2H) and catchment-integrated evaporation. Respectively, these controls form the basis of interpretations of precipitation isotope and effective precipitation signals from lake-water isotope proxy records. Conventionally, a single control on lake water isotope variability is assumed for a given record. Yet sensitivity to these controls depends on regional hydroclimate and local hydrology, which may change through time. We quantified the relative impacts of variations in inflow δ18O and evaporative 18O enrichment on lake water δ18O in response to spatially variable aridity, using measurements of lake water δ2H and δ18O from 140 western Greenland lakes located between the Labrador Sea and western Greenland Ice Sheet margin. We calculated source water δ18O of lake waters (δI) using a recently developed Bayesian method and quantified evaporation-to-inflow ratios (E/I) using a modified Craig-Gordon model. δI varied by 11.1‰ across the study region, superimposed by evaporative 18O enrichment of up to 20.0‰ and E/I ranging from nearly no evaporative loss (E/I 1). Lakes can be broadly classified as predominantly sensitive to inflow or evaporation, corresponding to their location along the aridity gradient, and there are significant trends in both δI and E/I across the study area. Substantial local variability in δI and E/I suggests catchment hydrology determines the sensitivity of δI and E/I to changes in aridity, and implies that hydrological end-member lakes within a small region may provide complementary records of seasonal precipitation isotope values and ice-free-season evaporation. Deconvolving modern controls on lake water isotope values provides essential support for quantitative and seasonal paleoclimate inferences from paleolimnological isotope data, which will improve constraints on the long-term variability of the Arctic hydrologic cycle.

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HighlightsEvaporation from clear water, manure, and separated liquid manure was 4.6 mm d-1 on average.Straw, foam, geotextile, and roof covers decreased evaporation by 54%, 53%, 31%, and 21%, respectively.Albedo was highest for floating foam covers and lowest for metal roof covers.Straw, foam, and geotextile increased manure temperature compared to uncovered manure. ABSTRACT. Evaporation is a key component of the surface energy budget of liquid manure. Models rely on accurate energy budgets to predict manure temperature, which in turn is used to model temperature-dependent greenhouse gas emissions from liquid manure storages. Due to lack of data, it has been assumed that liquid manure has similar evaporative properties to water; however, this assumption may be inaccurate. Many factors, including manure crusting, covers, and turbidity, are all likely to affect the surface energy budget and the evaporation rate. This experiment investigated the differences in evaporation between eight treatments, including water, dyed water, raw and separated liquid manure, and four commonly used covers (straw, geotextile, foam, and roof), by measuring weekly evaporation. Albedo, surface temperatures, and internal temperatures were also measured to determine treatment effects. Over the 10-week study, no significant difference was found between the evaporation rates of water, raw manure, and separated liquid manure, with an average rate of 4.6 mm d-1. Notably, the raw manure did not form a consistent surface crust, which may explain the similarities in evaporation rates in this study and is unlikely to represent manure with a crust. Overall, covers significantly decreased evaporative losses by between 21% and 54% compared to uncovered raw manure. Average evaporation rates of the covered treatments were 1.9 mm d-1 for straw cover, 2.0 mm d-1 for foam cover, 2.9 mm d-1 for geotextile cover, and 3.4 mm d-1 under a roof cover. Similarities between each treatment and water as well as between the four covered treatments and the uncovered raw manure were found using linear regression on weekly evaporation. Generally, the uncovered treatments were more similar and could be predicted (high R2) by multiple linear regression with environmental variables, while the covered treatments differed more and were not as well predicted (lower R2). Results from this study can help adjust evaporation rates in biophysical models to improve estimates of manure temperature, tank holding capacity, and emission predictions. Keywords: Evaporation, Dairy manure, Liquid manure, Manure covers, Manure management.

This cross-sectional study characterizes the prevalent use of medications that may raise BP and examine their associations with BP control and antihypertensive use.

Background: Guidelines advocate for the use of automated office-based blood pressure (AOBP) measurement to improve accuracy of blood pressure (BP) measurement in the outpatient clinical setting. Current recommendations include a 5-minute period of quiet rest prior to obtaining 3 readings, each separated by 1-2 minutes. As a result, AOBP requires a minimum of 7 minutes of rest time in addition to proper patient positioning plus cuff inflation and deflation, adding nearly 10 minutes to an office visit. Reducing this by even 1 minute has broad implications for the widespread use of AOBP. Methods: Patients from a single hypertension center underwent a 3-day evaluation that included a 24-hour ambulatory BP monitor (ABPM) and one of two, non-randomized, unattended AOBP protocols. Half of patients underwent 3 BP measurements separated by 30 seconds and the other half underwent 3 BP measurements separated by 60 seconds. All measurements were compared to the average awake-time BP from ABPM as well as the first AOBP measurement. Results: Among 102 patients, the average awake-time BP was 128.6±13.6/76.5±12.5 mmHg for the 30-second protocol and 132.5±15.6/77.7±12.2 mmHg among those who underwent the 60-second protocol . Mean BP was lower with the 2nd and 3rd AOBP measurement by -0.5/-1.7 mmHg and -1.0/-2.3 mmHg for the 60-second protocol versus -0.8/-2.0 mmHg and -0.7/-2.7 mmHg for the 30-second protocol ( Figure ). Differences between AOBP measurements (1st, 2nd, or 3rd) and awake-time ABPM were nearly identical across protocols. Conclusion: A 30-second interval between AOBP measurements was as accurate and reliable as a 60-second interval.

Background The Trial of Nonpharmacologic Interventions in the Elderly (TONE) demonstrated the efficacy of weight loss and sodium reduction to reduce hypertension medication use in older adults. However, the longer-term effects of drug withdrawal (DW) on blood pressure (BP), adverse events, and orthostatic symptoms were not reported. Methods TONE enrolled adults, ages 60–80 years, receiving treatment with a single antihypertensive and systolic BP (SBP)/diastolic BP Results Among the 975 participants (mean age 66 years, 48% women, 24% black), mean (±SD) BP was 128 ± 9/71 ± 7 mm Hg. Independent of assignment, DW increased SBP by 4.59 mm Hg (95% confidence interval [CI]: 3.89, 5.28) compared with baseline. There were 113 adverse events (84 symptomatic, 29 clinical), primarily during DW. Compared with usual care, combined weight loss and sodium reduction mitigated the effects of DW on BP (β = −4.33 mm Hg; 95% CI: −6.48, −2.17) and reduced orthostatic symptoms long term (odds ratio = 0.62; 95% CI: 0.41, 0.92), without affecting adverse events (hazard ratio = 1.81; 95% CI: 0.90, 3.65). In contrast, sodium reduction alone increased risk of adverse events (hazard ratio = 1.75; 95% CI: 1.04, 2.95), mainly during DW. Conclusions In older adults, antihypertensive DW may increase risk of symptomatic adverse events, highlighting the need for caution in withdrawing their antihypertensive medications. Clinical trials registration Trial Number NCT00000535.

Collaborative interprofessional primary care (PC) teams are widely seen as an essential attribute of high-performing PC systems (Aggarwal and Hutchinson 2012). Effective PC teams play a key role in the mobilization of healthcare resources and navigation of the health and social care system for their patients. In Ontario, the establishment of Family Health Teams has resulted in the implementation of unique programs that deliver services to palliative and elderly patients with a focus on keeping them at home and out of hospital. Case studies cited in this article highlight two innovative programs in Family Health Teams and provide perspectives on lessons for successful implementation.

CONTEXT There are limited data on the nature of environmental lead hazards identified during residential inspections for child blood lead levels (BLLs) of less than 10 μg/dL. We compare inspection findings for child BLLs of 5 to 9 μg/dL versus 10 μg/dL or more. DESIGN We reviewed inspection reports in Maine from September 2016 to March 2018. We used continuity-adjusted or Fisher's exact test for categorical variables and Wilcoxon rank-sum tests for continuous variables to compare differences in child, family, household, and lead hazard characteristics between BLL categories (5-9 μg/dL vs ≥10 μg/dL). We used Spearman correlation coefficients to assess relationships between home surface lead dust measurements and BLLs. RESULTS Of 351 residential inspections, 272 (77%) were for children with BLLs of 5 to 9 μg/dL. Children with BLLs of 5 to 9 μg/dL as compared with children with BLLs of 10 μg/dL or more were less likely to chew window sills and door frames (8% vs 21%; P = .01), but otherwise were similar with respect to other established risk factors for lead poisoning. Children with BLLs of 5 to 9 μg/dL tended to have fewer paint hazards inside their homes (64% vs 78%; P = .03), and they were more likely to have dust-only hazards (8% vs 3%) or no identified lead paint hazards (23% vs 15%), though these differences were not statistically significant. For children with BLLs of 5 to 9 μg/dL, BLL was weakly correlated with average window sill dust level (Spearman r = 0.16; P = .01) and average floor dust level (r = 0.13; P = .03), but these correlations were not observed for children with BLLs of 10 μg/dL and higher. CONCLUSIONS We have found that inspections of homes of children with BLLs of 5 to 9 μg/dL are nearly as likely to identify lead hazards that require abatement as inspections of homes of children with BLLs of 10 μg/dL.

Head and neck cancer survivors are increasing in prevalence, and 60-70% still experience at least one unmet emotional and/or physical need after treatment has ended. The purpose of this study was to determine the efficacy of a brief post-treatment psychoeducational intervention on perceived preparedness for coping with recovery using post-session evaluations.Between August 2013 and May 2018, a two-session, multidisciplinary "getting back on track" class was delivered to head and neck cancer patients approximately 2 months following radiation treatment at Princess Margaret Cancer Centre in Toronto, Canada. Three hundred and fifty attendees completed evaluations. Statistical analyses of the 310 patients surveyed measured change in level of preparedness to cope with recovery using the b-prepared scale. Qualitative analyses provided insight into potential benefits for future patients.Almost two-thirds (58%) of patients reported an increase in level of preparedness in post-intervention surveys. Comparing self-reported level of preparedness among patients from before to after the class showed an increase in feeling prepared from 50 to 58%, and of those feeling very prepared, from 6 to 34%. The proportion of patients who reported feeling unprepared (11%) or neutral (33%) before the class decreased post-intervention, with 0% feeling unprepared and 7% feeling neutral. There were statistically significant differences in the ideal timing of the class, but overall attendees agreed that the class is an essential part of their recovery.Results confirm the efficacy of this brief psychoeducational intervention to improve preparedness in head and neck cancer survivors following radiation treatment.

Background: The Trial of Nonpharmacologic Interventions in the Elderly (TONE) demonstrated the efficacy of sodium reduction and weight loss to reduce hypertension medication use in older adults. However, adverse events related to lightheadedness and falls have not been reported. Objective: To determine whether sodium reduction and weight loss are associated with greater risk of lightheadedness and falls among older adults. Methods: TONE was a randomized trial of 60-80 year-old adults with systolic BP (SBP) and diastolic BP (DBP) below 145 and 85 mm Hg, respectively, while receiving treatment with a single antihypertensive medication. Participants were randomized to behavioral interventions focused on sodium reduction, weight loss, both, or neither (usual care); 3 months after randomization, the antihypertensive medication was withdrawn and only restored later during the study if needed for uncontrolled hypertension. Total follow-up was 36 months post-randomization. Two physicians independently adjudicated adverse event logs, masked to intervention assignment. The primary outcome was a composite of the first occurrence of adverse event related to falls (total N=95): 72 involved orthostatic symptoms (lightheadedness, dizziness, vertigo), while 23 involved hard events (fall or syncope). Hazard ratios were determined via Cox proportional hazards models. Results: Among the 975 participants (mean age 66 yrs, 48% women, 24% black), mean SBP and DBP were 128 and 71 mm Hg. The cumulative incidence of adverse events at 30 months was 0.08, 0.13, 0.11, and 0.14 for usual care, reduced sodium, weight loss, or both, respectively ( Figure ). In adjusted multi-variable analyses, sodium reduction was associated with higher risk of an adverse event (HR 1.52; 95% CI: 1.02, 2.27), while weight loss was not associated with adverse events (HR 1.18; 0.77, 1.79). Conclusions: In the context of antihypertensive medication withdrawal, sodium reduction was associated with a higher risk of fall-related adverse events, predominantly symptoms.

The relative warmth of mid-to-late Pleistocene interglacials on Greenland has remained unknown, leading to debates about the regional climate forcing that caused past retreat of the Greenland Ice Sheet (GrIS). We analyze the hydrogen isotopic composition of terrestrial biomarkers in Labrador Sea sediments through interglacials of the past 600,000 y to infer millennial-scale summer warmth on southern Greenland. Here, we reconstruct exceptionally warm summers in Marine Isotope Stage (MIS) 5e, concurrent with strong Northern Hemisphere summer insolation. In contrast, “superinterglacial” MIS11 demonstrated only moderate warmth, sustained throughout a prolonged interval of elevated atmospheric carbon dioxide. Strong inferred GrIS retreat during MIS11 relative to MIS5e suggests an indirect relationship between maximum summer temperature and cumulative interglacial mass loss, indicating strong GrIS sensitivity to duration of regional warmth and elevated atmospheric carbon dioxide.