Purpose
This contribution reviews the evolution of sediment source fingerprinting investigations since the beginning of such studies in the mid-1970s. Attention is directed to key advances and ...developments during this period, to the present status of source fingerprinting techniques and to the scope for future development.
Scope
An analysis of the number of papers reporting sediment source fingerprinting investigations or associated methodologies published annually since the mid-1970s to date indicates that the number of such papers has increased near exponentially. The key drivers behind the expansion of such work are examined and linked to both the progress of academic enquiry and the need to support the development of sediment management strategies aimed at countering environmental problems associated with fine sediment. Instead of providing a chronological review of the various advances and developments evidenced by the expanding literature, attention focuses on seven key areas of development which are seen as having together contributed to the current state of the art. These include the expanding range of fingerprint properties employed; the use of statistical tests to confirm the ability of particular fingerprint properties to discriminate between potential sources and to assist in the selection of the ‘best’ properties for inclusion in the final composite fingerprint; the use of numerical mixing models to obtain quantitative estimates of the relative contribution of different sources; recognition of the need to confirm the conservative behaviour of the sediment properties employed as fingerprints and to take account of contrasts in grain size composition and organic matter content between source material and target samples; extension of the approach to include a greater range of targets and potential sources; addition of a temporal dimension, in order to consider changes in sediment source through time; and recognition of the need to direct increased attention to the uncertainty associated with the results of such studies. At the present time, sediment source fingerprinting techniques can be seen as being in a transition from a scientific tool to an operational or management tool, but further development will be required before successful transition to the latter can be fully achieved.
Background Studies suggest an association between acute kidney injury (AKI) and long-term risk for chronic kidney disease (CKD), even following apparent renal recovery. Whether the pattern of renal ...recovery predicts kidney risk following AKI is unknown. Study Design Retrospective cohort. Setting & Participants Patients in the Veterans Health Administration in 2011 hospitalized (>24 hours) with at least 2 inpatient serum creatinine measurements, baseline estimated glomerular filtration rate > 60 mL/min/1.73 m2 , and no diagnosis of end-stage renal disease or non−dialysis-dependent CKD: 17,049 (16.3%) with and 87,715 without AKI. Predictor Pattern of recovery to creatinine level within 0.3 mg/dL of baseline after AKI: within 2 days (fast), in 3 to 10 days (intermediate), and no recovery by 10 days (slow or unknown). Outcome CKD stage 3 or higher, defined as 2 outpatient estimated glomerular filtration rates < 60 mL/min/1.73 m2 at least 90 days apart or CKD diagnosis, dialysis therapy, or transplantation. Measurements Risk for CKD was modeled using modified Poisson regression and time to death-censored CKD was modeled using Cox proportional hazards regression, both stratified by AKI stage. Results Most patients’ AKI episodes were stage 1 (91%) and 71% recovered within 2 days. At 1 year, 18.2% had developed CKD (AKI, 31.8%; non-AKI, 15.5%; P < 0.001). In stage 1, the adjusted relative risk ratios for CKD stage 3 or higher were 1.43 (95% CI, 1.39-1.48), 2.00 (95% CI, 1.88-2.12), and 2.65 (95% CI, 2.51-2.80) for fast, intermediate, and slow/unknown recovery. A similar pattern was observed in subgroup analyses incorporating albuminuria and sensitivity analysis of death-censored time to CKD. Limitations Variable timing of follow-up and mostly male veteran cohort may limit generalizability. Conclusions Patients who develop AKI during a hospitalization are at substantial risk for the development of CKD by 1 year following hospitalization and timing of AKI recovery is a strong predictor, even for the mildest forms of AKI.
Highlights • Cerebellum involved in various aspects of performance monitoring. • Contributions to sensory prediction, error and response conflict processing. • Contributions to response inhibition, ...feedback learning, articulatory monitoring. • Cerebellum at the interface of motor behavior and cognition. • Monitoring as overarching cerebellar function.
Rivers originating in High Mountain Asia are crucial lifelines for one-third of the world’s population. These fragile headwaters are now experiencing amplified climate change, glacier melt, and ...permafrost thaw. Observational data from 28 headwater basins demonstrate substantial increases in both annual runoff and annual sediment fluxes across the past six decades. The increases are accelerating from the mid-1990s in response to a warmer and wetter climate. The total sediment flux from High Mountain Asia is projected to more than double by 2050 under an extreme climate change scenario. These findings have far-reaching implications for the region’s hydropower, food, and environmental security.
Background Awareness of chronic kidney disease (CKD), defined by kidney damage or reduced glomerular filtration rate, remains low in the United States, and few estimates of its future burden exist. ...Study Design We used the CKD Health Policy Model to simulate the residual lifetime incidence of CKD and project the prevalence of CKD in 2020 and 2030. The simulation sample was based on nationally representative data from the 1999 to 2010 National Health and Nutrition Examination Surveys. Setting & Population Current US population. Model, Perspective, & Timeline Simulation model following up individuals from current age through death or age 90 years. Outcomes Residual lifetime incidence represents the projected percentage of persons who will develop new CKD during their lifetimes. Future prevalence is projected for 2020 and 2030. Measurements Development and progression of CKD are based on annual decrements in estimated glomerular filtration rates that depend on age and risk factors. Results For US adults aged 30 to 49, 50 to 64, and 65 years or older with no CKD at baseline, the residual lifetime incidences of CKD are 54%, 52%, and 42%, respectively. The prevalence of CKD in adults 30 years or older is projected to increase from 13.2% currently to 14.4% in 2020 and 16.7% in 2030. Limitations Due to limited data, our simulation model estimates are based on assumptions about annual decrements in estimated glomerular filtration rates. Conclusions For an individual, lifetime risk of CKD is high, with more than half the US adults aged 30 to 64 years likely to develop CKD. Knowing the lifetime incidence of CKD may raise individuals’ awareness and encourage them to take steps to prevent CKD. From a national burden perspective, we estimate that the population prevalence of CKD will increase in coming decades, suggesting that development of interventions to slow CKD onset and progression should be considered.
Combinations of climatic zones and human activities (A and B denote types of conservation and exploitation activities respectively) well correspond to the nine water-sediment co-varying trends (S, D, ...and I represent stable, decrease and increase trends respectively) in the world’s large rivers distributed globally.
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Water and sediment transport from rivers to oceans is of primary importance in global geochemical cycle. Against the background of global change, this study examines the changes in water and sediment fluxes and their drivers for 4307 large rivers worldwide (basin area ≥1000 km2) based on the longest available records. Here we find that 24% of the world’s large rivers experienced significant changes in water flux and 40% in sediment flux, most notably declining trends in water and sediment fluxes in Asia’s large rivers and an increasing trend in suspended sediment concentrations in the Amazon River. In particular, nine binary patterns of changes in water-sediment fluxes are interpreted in terms of climate change and human impacts. The change of precipitation is found significantly correlated to the change of water flux in 71% of the world’s large rivers, while dam operation and irrigation rather control the change of sediment flux in intensively managed catchments. Globally, the annual water flux from rivers to sea of the recent years remained stable compared with the long-time average annual value, while the sediment flux has decreased by 20.8%.
A variety of catalysts have recently been developed for electrocatalytic oxygen evolution, but very few of them can be readily integrated with semiconducting light absorbers for photoelectrochemical ...or photocatalytic water splitting. Here, we demonstrate an efficient core/shell photoanode with a highly active oxygen evolution electrocatalyst shell (FeMnP) and semiconductor core (rutile TiO2) for photoelectrochemical oxygen evolution reaction. Metal–organic chemical vapor deposition from a single-source precursor was used to ensure good contact between the FeMnP and the TiO2. The TiO2/FeMnP core/shell photoanode reaches the theoretical photocurrent density for rutile TiO2 of 1.8 mA cm–2 at 1.23 V vs reversible hydrogen electrode under simulated 100 mW cm–2 (1 sun) irradiation. The dramatic enhancement is a result of the synergistic effects of the high oxygen evolution reaction activity of FeMnP (delivering an overpotential of 300 mV with a Tafel slope of 65 mV dec–1 in 1 M KOH) and the conductive interlayer between the surface active sites and semiconductor core which boosts the interfacial charge transfer and photocarrier collection. The facile fabrication of the TiO2/FeMnP core/shell nanorod array photoanode offers a compelling strategy for preparing highly efficient photoelectrochemical solar energy conversion devices.
Preventive care for adults with diabetes has improved substantially in recent decades. We examined trends in the incidence of diabetes-related complications in the United States from 1990 through ...2010.
We used data from the National Health Interview Survey, the National Hospital Discharge Survey, the U.S. Renal Data System, and the U.S. National Vital Statistics System to compare the incidences of lower-extremity amputation, end-stage renal disease, acute myocardial infarction, stroke, and death from hyperglycemic crisis between 1990 and 2010, with age standardized to the U.S. population in the year 2000.
Rates of all five complications declined between 1990 and 2010, with the largest relative declines in acute myocardial infarction (-67.8%; 95% confidence interval CI, -76.2 to -59.3) and death from hyperglycemic crisis (-64.4%; 95% CI, -68.0 to -60.9), followed by stroke and amputations, which each declined by approximately half (-52.7% and -51.4%, respectively); the smallest decline was in end-stage renal disease (-28.3%; 95% CI, -34.6 to -21.6). The greatest absolute decline was in the number of cases of acute myocardial infarction (95.6 fewer cases per 10,000 persons; 95% CI, 76.6 to 114.6), and the smallest absolute decline was in the number of deaths from hyperglycemic crisis (-2.7; 95% CI, -2.4 to -3.0). Rate reductions were larger among adults with diabetes than among adults without diabetes, leading to a reduction in the relative risk of complications associated with diabetes. When expressed as rates for the overall population, in which a change in prevalence also affects complication rates, there was a decline in rates of acute myocardial infarction and death from hyperglycemic crisis (2.7 and 0.1 fewer cases per 10,000, respectively) but not in rates of amputation, stroke, or end-stage renal disease.
Rates of diabetes-related complications have declined substantially in the past two decades, but a large burden of disease persists because of the continued increase in the prevalence of diabetes. (Funded by the Centers for Disease Control and Prevention.).
Background Little is known about patterns of kidney function decline leading up to the initiation of long-term dialysis. Study Design Retrospective cohort study. Setting & Participants 5,606 Veterans ...Affairs patients who initiated long-term dialysis in 2001-2003. Predictor Trajectory of estimated glomerular filtration rate (eGFR) during the 2-year period before initiation of long-term dialysis. Outcomes & Measurements Patient characteristics and care practices before and at the time of dialysis initiation and survival after initiation. Results We identified 4 distinct trajectories of eGFR during the 2-year period before dialysis initiation: 62.8% of patients had persistently low level of eGFR <30 mL/min/1.73 m2 (mean eGFR slope, 7.7 ± 4.7 SD mL/min/1.73 m2 per year), 24.6% had progressive loss of eGFR from levels of approximately 30-59 ml/min/1.73 m2 (mean eGFR slope, 16.3 ± 7.6 mL/min/1.73 m2 per year), 9.5% had accelerated loss of eGFR from levels >60 mL/min/1.73 m2 (mean eGFR slope, 32.3 ± 13.4 mL/min/1.73 m2 per year), and 3.1% experienced catastrophic loss of eGFR from levels >60 mL/min/1.73 m2 within 6 months or less. Patients with steeper eGFR trajectories were more likely to have been hospitalized and have an inpatient diagnosis of acute kidney injury. They were less likely to have received recommended predialysis care and had a higher risk of death in the first year after dialysis initiation. Conclusions There is substantial heterogeneity in patterns of kidney function loss leading up to the initiation of long-term dialysis perhaps calling for a more flexible approach toward preparing for end-stage renal disease.
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