Carbon Capture and Storage may use deep saline aquifers for CO 2 sequestration, but small CO 2 leakage could pose a risk to overlying fresh groundwater. We performed laboratory incubations of CO 2 infiltration under oxidizing conditions for >300 days on samples from four freshwater aquifers to 1) understand how CO 2 leakage affects freshwater quality; 2) develop selection criteria for deep sequestration sites based on inorganic metal contamination caused by CO 2 leaks to shallow aquifers; and 3) identify geochemical signatures for early detection criteria. After exposure to CO 2 , water pH declines of 1-2 units were apparent in all aquifer samples. CO 2 caused concentrations of the alkali and alkaline earths and manganese, cobalt, nickel, and iron to increase by more than 2 orders of magnitude. Potentially dangerous uranium and barium increased throughout the entire experiment in some samples. Solid-phase metal mobility, carbonate buffering capacity, and redox state in the shallow overlying aquifers influence the impact of CO 2 leakage and should be considered when selecting deep geosequestration sites. Manganese, iron, calcium, and pH could be used as geochemical markers of a CO 2 leak, as their concentrations increase within 2 weeks of exposure to CO 2 .
Stable oxygen isotope data from four holes drilled at the Ocean Drilling Program Site 967, which is located on the lower northern slope of the Eratosthenes Seamount, provide a continuous record of Eastern Mediterranean surface-water conditions during the last 3.2 Ma. A high-resolution stratigraphy for the Pliocene-Pleistocene sequence was established by using a combination of astronomical calibration of sedimentary cycles, nannofossil stratigraphy, and stable oxygen isotope fluctuations. Sapropels and color cycles are present throughout the last 3.2 Ma at Site 967, and their ages, as determined by calibration against the precessional component of the astronomical record, are consistent with those estimated for the sapropels of the classical land-based marine sequences of the Punta Piccola, San Nicola, Singa, and Vrica sections (southern Italy). The Site 967 oxygen isotope record shows large amplitude fluctuations mainly caused by variations in surface water salinity throughout the entire period. Spectral analysis shows that fluctuations in the δ 18O record were predominantly influenced by orbital obliquity and precessional forcing from 3.2 to 1 Ma, and all main orbital frequencies characterize the δ 18 O record for the last million years. The start of sapropel formation at 3.2 Ma indicates a possible link between sapropel formation and the build up of northern hemisphere ice sheets. The dominance of the obliquity cycle in the interval from 3.2−1 Ma further points to the sensitivity of Eastern Mediterranean climate to the fluctuations in the volume of Arctic ice sheets. An intensification of negative isotope anomalies at Site 967, relative to the open ocean, supports a link between high run-off (during warm periods) and sapropel formation. freshwater input would have inhibited deep-water formation, which led to stagnation of deeper waters. Comparison with the land sections also confirms that differential preservation and diagenesis play a key role in sapropel occurrence.
Introduction The geriatric syndromes of frailty, sarcopenia, weight loss, and dementia are highly prevalent in elderly individuals across all care continuums. Despite their deleterious impact on quality of life, disability, and mortality in older adults, they are frequently under-recognized. At Saint Louis University, the Rapid Geriatric Assessment (RGA) was developed as a brief screening tool to identify these four geriatric syndromes. Materials and methods From 2015-2019, the RGA, comprised of the FRAIL, SARC-F, Simplified Nutritional Appetite Questionnaire (SNAQ), and Rapid Cognitive Screen (RCS) tools and a question on Advance Directives, was administered to 11,344 individuals � 65 years of age across Missouri in community, office-based, hospital, Programs of All-Inclusive Care for the Elderly (PACE), and nursing home care settings. Standard statistical methods were used to calculate the prevalence of frailty, sarcopenia, weight loss, and dementia across the sample. Results Among the 11,344 individuals screened by the RGA, 41.0% and 30.4% met the screening criteria for pre-frailty and frailty respectively, 42.9% met the screening criteria for sarcopenia, 29.3% were anorectic and at risk for weight loss, and 28.1% screened positive for dementia. The prevalence of frailty, risk for weight loss, sarcopenia, and dementia increased with age and decreased when hospitalized patients and those in the PACE program or nursing home were excluded. Conclusions Using the RGA as a valid screening tool, the prevalence of one or more of the geriatric syndromes of frailty, sarcopenia, weight loss, and dementia in older adults across all care
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