Abstract Coastal morphological changes can be assessed using shoreline position observations from space. However, satellite-derived waterline (SDW) and shoreline (SDS; SDW corrected for hydrodynamic ...contributions and outliers) detection methods are subject to several sources of uncertainty and inaccuracy. We extracted high-spatiotemporal-resolution (~50 m-monthly) time series of mean high water shoreline position along the Columbia River Littoral Cell (CRLC), located on the US Pacific Northwest coast, from Landsat missions (1984–2021). We examined the accuracy of the SDS time series along the mesotidal, mildly sloping, high-energy wave climate and dissipative beaches of the CRLC by validating them against 20 years of quarterly in situ beach elevation profiles. We found that the accuracy of the SDS time series heavily depends on the capability to identify and remove outliers and correct the biases stemming from tides and wave runup. However, we show that only correcting the SDW data for outliers is sufficient to accurately measure shoreline change trends along the CRLC. Ultimately, the SDS change trends show strong agreement with in situ data, facilitating the spatiotemporal analysis of coastal change and highlighting an overall accretion signal along the CRLC during the past four decades.
Increasing exposure to coastal flood hazards will potentially induce an enormous socio‐economic toll on vulnerable communities. To accurately characterize the hazard, we must consider both natural ...water level variability and climate change‐induced sea‐level rise. In this study, we develop a paleo‐proxy‐based reconstruction of coastal flood events over the last 500 yr to capture natural water level variability and superimpose that reconstruction onto expected sea‐level rise to explore interannual and multidecadal variability in plausible future coastal flood risk. We first develop reconstructions of leading principal components (PCs) of sea surface temperature anomalies from 1500 CE onwards, using tree‐ring, coral, and sclerosponge chronology‐based El Niño Southern Oscillation reconstructions as predictors in a wavelet autoregression model. These reconstructions of PCs are then used in a stochastic water level emulator to develop ensemble simulations of hourly still water levels (SWLs) in the San Francisco Bay. The emulator accounts for multiple relevant processes, including monthly mean sea level (MMSL) anomalies, storm surge, and tide, all varying at different timescales. Accounting for natural variability in water levels over 1500–2000 CE increases coastal flood risk beyond that suggested by instrumental records alone. When superimposed on 0.22 m of sea‐level rise (approximately the amount experienced over the previous century), the simulations show that while high tides and large storm surges cause the smaller extreme SWLs, the larger extreme SWLs occur during concurrent high MMSL, high tides, and significant storm surges. Our findings thus highlight the need to consider natural water level variability for coastal adaptation and planning.
Plain Language Summary
Increasing exposure to coastal flood hazards will potentially induce an enormous socio‐economic toll on vulnerable communities. To accurately characterize the flood risk, we must consider both natural water level variability and climate change‐induced sea‐level rise. But we need long records of sea level conditions to quantify the natural variability and characterize the associated extreme flood levels. Paleo‐proxies, such as corals, sponges, and tree rings, capture these long‐term conditions during times when modern instrumental records were unavailable. Using this paleo‐proxy‐based data, we have developed 500 yr long simulations of coastal water levels using specialized computer models that account for several climate and weather patterns and estimates of sea surface temperature conditions from 1500 to 2000. We use these long simulations to quantify the natural fluctuations in coastal water levels at annual and decadal time scales. When we consider the full extent of such fluctuations, coastal flood risk increases beyond the current flooding thresholds in San Francisco Bay, our study site. Our findings suggest a strong need to account for natural water level fluctuations in addition to projections of sea‐level rise for any future coastal adaptation planning.
Key Points
Paleo‐proxy based reconstructions of hourly coastal water level components are produced using a stochastic water level emulator
Considering natural variability in water levels over 1500–2000 CE increases coastal flood risk beyond that suggested by instrumental records
When superimposed on sea‐level rise, natural variability in coastal water level can significantly increase extreme coastal water levels
It is not understood how Hsp104, a hexameric AAA+ ATPase from yeast, disaggregates diverse structures, including stress-induced aggregates, prions, and α-synuclein conformers connected to Parkinson ...disease. Here, we establish that Hsp104 hexamers adapt different mechanisms of intersubunit collaboration to disaggregate stress-induced aggregates versus amyloid. To resolve disordered aggregates, Hsp104 subunits collaborate noncooperatively via probabilistic substrate binding and ATP hydrolysis. To disaggregate amyloid, several subunits cooperatively engage substrate and hydrolyze ATP. Importantly, Hsp104 variants with impaired intersubunit communication dissolve disordered aggregates, but not amyloid. Unexpectedly, prokaryotic ClpB subunits collaborate differently than Hsp104 and couple probabilistic substrate binding to cooperative ATP hydrolysis, which enhances disordered aggregate dissolution but sensitizes ClpB to inhibition and diminishes amyloid disaggregation. Finally, we establish that Hsp104 hexamers deploy more subunits to disaggregate Sup35 prion strains with more stable “cross-β” cores. Thus, operational plasticity enables Hsp104 to robustly dissolve amyloid and nonamyloid clients, which impose distinct mechanical demands.
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► Hsp104 switches mechanism to disaggregate disordered aggregates versus amyloid ► ClpB operates with reduced plasticity and has limited amyloid-disaggregase activity ► Hsp104 remodels diverse toxic oligomers and amyloids linked to neurodegeneration ► Hsp104 plasticity enables yeast to harness prions for advantageous purposes
The protein disaggregase Hsp104 from yeast employs different mechanisms to resolve disordered aggregates versus amyloid. Conversely, its bacterial homolog ClpB displays reduced operational plasticity and limited amyloid-remodeling activity.
Although the burden of disease in sub-Saharan Africa continues to be dominated by infectious diseases, countries in this region are undergoing a demographic transition leading to increasing ...prevalence of non-communicable diseases (NCDs). To inform health system responses to these changing patterns of disease, we aimed to assess changes in the burden of NCDs in sub-Saharan Africa from 1990 to 2017.
We used data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 to analyse the burden of NCDs in sub-Saharan Africa in terms of disability-adjusted life-years (DALYs)—with crude counts as well as all-age and age-standardised rates per 100 000 population—with 95% uncertainty intervals (UIs). We examined changes in burden between 1990 and 2017, and differences across age, sex, and regions. We also compared the observed NCD burden across countries with the expected values based on a country's Socio-demographic Index.
All-age total DALYs due to NCDs increased by 67·0% between 1990 (90·6 million 95% UI 81·0–101·9) and 2017 (151·3 million 133·4–171·8), reflecting an increase in the proportion of total DALYs attributable to NCDs (from 18·6% 95% UI 17·1–20·4 to 29·8% 27·6–32·0 of the total burden). Although most of this increase can be explained by population growth and ageing, the age-standardised DALY rate (per 100 000 population) due to NCDs in 2017 (21 757·7 DALYs 95% UI 19 377·1–24 380·7) was almost equivalent to that of communicable, maternal, neonatal, and nutritional diseases (26 491·6 DALYs 25 165·2–28 129·8). Cardiovascular diseases were the second leading cause of NCD burden in 2017, resulting in 22·9 million (21·5–24·3) DALYs (15·1% of the total NCD burden), after the group of disorders categorised as other NCDs (28·8 million 25·1–33·0 DALYs, 19·1%). These categories were followed by neoplasms, mental disorders, and digestive diseases. Although crude DALY rates for all NCDs have decreased slightly across sub-Saharan Africa, age-standardised rates are on the rise in some countries (particularly those in southern sub-Saharan Africa) and for some NCDs (such as diabetes and some cancers, including breast and prostate cancer).
NCDs in sub-Saharan Africa are posing an increasing challenge for health systems, which have to date largely focused on tackling infectious diseases and maternal, neonatal, and child deaths. To effectively address these changing needs, countries in sub-Saharan Africa require detailed epidemiological data on NCDs.
Bill & Melinda Gates Foundation, National Health and Medical Research Centre (Australia).
New York State (NYS) is an epicenter of the SARS-CoV-2 pandemic in the United States. Reliable estimates of cumulative incidence in the population are critical to tracking the extent of transmission ...and informing policies.
We conducted a statewide seroprevalence study in a 15,101 patron convenience sample at 99 grocery stores in 26 counties throughout NYS. SARS-CoV-2 cumulative incidence was estimated from antibody reactivity by first poststratification weighting and then adjusting by antibody test characteristics. The percent diagnosed was estimated by dividing the number of diagnoses by the number of estimated infection-experienced adults.
Based on 1887 of 15,101 (12.5%) reactive results, estimated cumulative incidence through March 29 was 14.0% (95% confidence interval CI: 13.3%–14.7%), corresponding to 2,139,300 (95% CI: 2,035,800–2,242,800) infection-experienced adults. Cumulative incidence was highest in New York City 22.7% (95% CI: 21.5%–24.0%) and higher among Hispanic/Latino (29.2%), non-Hispanic black/African American (20.2%), and non-Hispanic Asian (12.4%) than non-Hispanic white adults (8.1%, P < .0001). An estimated 8.9% (95% CI: 8.4%–9.3%) of infections in NYS were diagnosed, with diagnosis highest among adults aged 55 years or older (11.3%, 95% CI: 10.4%–12.2%).
From the largest U.S. serosurvey to date, we estimated >2 million adult New York residents were infected through late March, with substantial disparities, although cumulative incidence remained less than herd immunity thresholds. Monitoring, testing, and contact tracing remain essential public health strategies.
Objectives The goal of this study was to compare the diagnostic accuracy of combined computed tomography perfusion (CTP) + computed tomography angiography (CTA), transluminal attenuation gradient by ...320-detector row computed tomography (TAG320) + CTA, and CTP + TAG320 + CTA (multidetector computed tomography–integrated protocol MDCT-IP) assessment in predicting significant fractional flow reserve (FFR). Background CTA has limited specificity for predicting functionally significant stenoses. Novel CT techniques, including adenosine stress CTP and TAG320, may improve the diagnostic accuracy of CTA. Methods CTA, CTP, and TAG320 were assessed using 320-detector row MDCT. Patients who underwent CTA, CTP, and FFR assessment on invasive coronary angiography were included. CTP was assessed using the visual perfusion assessment. TAG320 was defined as the linear regression coefficient between luminal attenuation and axial distance. A TAG320 cutoff value of −15.1 HU/10 mm as previously described was defined as significant. Functionally significant coronary stenosis was defined as FFR ≤0.8. Results The cohort included 75 patients (age 64.1 ± 10.8 years, 52 men) and 44 (35%) FFR-significant vessels. In 127 vessels, CTA predicted FFR-significant stenosis with 89% sensitivity and 65% specificity compared with MDCT-IP, which showed 88% sensitivity and 83% specificity. In 97 vessels in which the results of all techniques were available, TAG320 + CTA (area under the curve AUC = 0.844) and CTP + CTA (AUC = 0.845) had comparable per-vessel diagnostic accuracy (p = 0.98). The diagnostic accuracy of MDCT-IP (AUC = 0.91) was superior to TAG320 + CTA or CTP + CTA (p = 0.01). Conclusions In vessels without significant calcification or artefact, TAG320 + CTA and CTP + CTA provide comparable diagnostic accuracy for functional assessment of coronary artery stenosis. MDCT-IP may provide the best diagnostic accuracy for functional assessment of coronary artery stenosis.
The purpose of this study was to assess the diagnostic accuracy of TAG320 in predicting functional stenosis severity evaluated by fractional flow reserve (FFR).
Coronary computed tomography ...angiography (CCTA) has limited specificity for predicting functionally significant stenoses. Recent studies suggest that contrast gradient attenuation along an arterial lesion, or transluminal attenuation gradient (TAG), may provide assessment of functional significance of coronary stenosis. The use of 320-detector row computed tomography (CT), enabling near isophasic, single-beat imaging of the entire coronary tree, may be ideal for TAG functional assessment of a coronary arterial stenosis.
We assessed the diagnostic accuracy of TAG320 using 320-row CCTA with FFR for the evaluation of functional stenosis severity in consecutive patients undergoing invasive coronary angiography and FFR for stable chest pain. The luminal radiological contrast attenuation (Hounsfield units HU) was measured at 5-mm intervals along the artery from ostium to a distal level where the cross-sectional area decreased to <2.0 mm(2). TAG320 was defined as the linear regression coefficient between luminal attenuation and axial distance. Functionally significant coronary stenosis was defined as ≤0.8 on FFR.
In our cohort of 54 patients (age 62.7 ± 8.7 years, 35 men, 78 vessels), TAG320 in FFR-significant vessels was significantly lower when compared with FFR nonsignificant vessels (-21 -27; -16 vs. -11 -16; -3 HU/10 mm, p < 0.001). On receiver-operating characteristic analysis, a retrospectively determined TAG320 cutoff of -15.1 HU/10 mm predicted FFR ≤0.8 with (a bootstrapped resampled) a sensitivity of 77%, specificity of 74%, positive predictive value of 67%, and negative predictive value of 86%. The combined TAG320 and CCTA assessment had an area under the curve of 0.88. There was incremental value of adding TAG320 to CCTA assessment for detection of significant FFR by Wald test (p = 0.0001) and integrated discrimination improvement index (0.11, p = 0.002).
Assessment of TAG320 with a 320-detector row CT provides acceptable prediction of invasive FFR and may provide a noninvasive modality for detecting functionally significant coronary stenoses. Combined TAG320 and CCTA assessment may have incremental predictive value over CCTA alone for detecting functionally significant coronary arterial stenoses; however, larger studies are required to determine the benefit of combined TAG320 and CCTA assessment.
As a distinct group, 2- to 5-year-olds with severe obesity (SO) have not been extensively described. As a part of the Expert Exchange Workgroup on Childhood Obesity, nationally-representative data ...were examined to better characterize children with SO.
Children ages 2 to 5 (
= 7028) from NHANES (1999-2014) were classified as having normal weight, overweight, obesity, or SO (BMI ≥120% of 95th percentile). Sociodemographics, birth characteristics, screen time, total energy, and Healthy Eating Index 2010 scores were evaluated. Multinomial logistic and linear regressions were conducted, with normal weight as the referent.
The prevalence of SO was 2.1%. Children with SO had higher (unadjusted) odds of being a racial and/or ethnic minority (African American: odds ratio OR: 1.7; Hispanic: OR: 2.3). They were from households with lower educational attainment (OR: 2.4), that were single-parent headed (OR: 2.0), and that were in poverty (OR: 2.1). Having never been breastfed was associated with increased odds of obesity (OR: 1.5) and higher odds of SO (OR: 1.9). Odds of >4 hours of screen time were 1.5 and 2.0 for children with obesity and SO. Energy intake and Healthy Eating Index 2010 scores were not significantly different in children with SO.
Children ages 2 to 5 with SO appear to be more likely to be of a racial and/or ethnic minority and have greater disparities in social determinants of health than their peers and are more than twice as likely to engage in double the recommended screen time limit.
The systolic forward travelling compression wave (sFCW) and diastolic backward travelling decompression waves (dBEW) predominantly accelerate coronary blood flow. The effect of a coronary stenosis on ...the intensity of these waves in the distal vessel is unknown. We investigated the relationship between established physiological indices of hyperemic coronary flow and the intensity of the two major accelerative coronary waves identified by Coronary Wave Intensity analysis (CWIA).
Simultaneous intracoronary pressure and velocity measurement was performed during adenosine induced hyperemia in 17 patients with pressure / Doppler flow wires positioned distal to the target lesion. CWI profiles were generated from this data. Fractional Flow Reserve (FFR) and Coronary Flow Velocity Reserve (CFVR) were calculated concurrently. The intensity of the dBEW was significantly correlated with FFR (R = -0.70, P = 0.003) and CFVR (R = -0.73, P = 0.001). The intensity of the sFCW was also significantly correlated with baseline FFR (R = 0.71, p = 0.002) and CFVR (R = 0.59, P = 0.01). Stenting of the target lesion resulted in a median 178% (interquartile range 55-280%) (P<0.0001) increase in sFCW intensity and a median 117% (interquartile range 27-509%) (P = 0.001) increase in dBEW intensity. The increase in accelerative wave intensity following PCI was proportionate to the baseline FFR and CFVR, such that stenting of lesions associated with the greatest flow limitation (lowest FFR and CFVR) resulted in the largest increases in wave intensity.
Increasing ischemia severity is associated with proportionate reductions in cumulative intensity of both major accelerative coronary waves. Impaired diastolic microvascular decompression may represent a novel, important pathophysiologic mechanism driving the reduction in coronary blood flow in the setting of an epicardial stenosis.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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