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In this study, we investigate chemical and isotopic characteristics of low-temperature geothermal waters issuing from carbonate reservoirs in the Çürüksu Graben within the eastern termination of the Büyük Menderes Graben in western Turkey. Temperatures and pH values of geothermal waters vary from 20.1 to 24.6 ºC and 6.62 to 7.11 and those of cold waters are 17.1 to 19.9 ºC and 6.85 to 7.72, respectively. Geothermal waters are of Ca-HCO3 and Ca-SO4 types whereas cold waters are characterized by these two types and Mg-HCO3 as well. δ18O and δD values of samples vary from –9.27‰ to –7.69‰ (VSMOW) and –58.06‰ to –52.2‰ and indicate a meteoric origin with local recharge. Tritium contents are from 0.12 to 2.17 TU for thermal waters and 0.28 to 4.85 TU for the cold waters implying relatively longer residence time for the hot waters. Thermal water samples mostly have positive δ13C values (varying from –0.32‰ to +1.99‰) and carbon in these waters is likely derived from marine limestone or metamorphic CO2 . δ34S and δ18O values of dissolved sulfate in the waters indicate that sulfur originates from dissolution of marine evaporite deposits (e.g., gypsum). Çürüksu waters are generally oversaturated with respect to calcite, dolomite and quartz but undersaturated with respect to gypsum. Common ion effect exerted a strong control for the formation of travertine deposits in the area. Chemical and isotopic evaluations indicated that the diversity in the water chemistry of samples is attributed to a combination of processes including water-rock interaction, ion exchange and mixing of various types of waters. Çürüksu thermal waters are immature and not in chemical equilibrium with the reservoir rock. Among the various geothermometers applied to Çürüksu thermal waters, temperatures computed by chalcedony, quartz and CaMg geothermometers are 21–52 ºC, 49–83 ºC and 73–96 ºC, respectively. HCO3 -SO4 -F and anhydrite-chalcedony (quartz) diagrams estimated a temperature range of 63–86 ºC and δ18O(SO4 -H2O) isotope geothermometer yielded 67–78 ºC. [ABSTRACT FROM AUTHOR]

Background/aim: The predictability of clinical outcomes in hypertension in specific patient groups, especially underrepresented populations is the key to rational treatment. This study aimed to investigate the impact of baseline characteristics of <65-year-old hypertensive women with an increased risk of cardiovascular events, managed with standard- or intensive-approach, on their clinical outcomes and serious adverse events (SAEs). Materials and methods: Baseline characteristics of <65-year-old hypertensive women (n = 1247) in SPRINT, a multicenter randomized trial to compare standard and intensive antihypertensive treatment, were analyzed with Cox-regression method to determine potential predictors of the clinical outcomes and SAEs. The primary outcome was the composite of myocardial infarction (MI), non-MI acute coronary syndrome, stroke, heart failure, or cardiovascular death. Results: The primary outcome occurred in 3.1% and SAEs in 27.6% of the population. The treatment groups were similar in terms of the primary outcome, SAEs, or their individual components. The primary outcome occurred significantly more in current smokers vs. nonsmokers (HR: 2.85, 95% CI: 1.34–6.09). The subjects who were on aspirin in the intensive-group were significantly more likely to develop the primary outcome (HR: 3.17, 95% CI: 1.23-8.19) and MI (HR: 10.15, 95% CI: 1.19-86.88) compared with those not using aspirin. The risk of overall SAEs was significantly higher in blacks vs. nonblacks (HR: 1.27, 95% CI: 1.01-1.58), in current-smokers vs. nonsmokers (HR: 1.59, 95% CI: 1.23-2.05), and those with vs. without chronic kidney disease (CKD), (HR: 1.38, 95% CI: 1.08-1.77). The likelihood of SAEs significantly increased with age (HR: 1.04, 95% CI: 1.01-1.07). Conclusion: Smoking, aspirin, CKD, black race, and age seemed as important baseline characteristics in follow-up of <65-year-old hypertensive women, also depending on therapeutic strategy. Clinicians are expected to consider these critical parameters for effective antihypertensive management that promotes better outcomes in this middle-aged female population. [ABSTRACT FROM AUTHOR]