50 research outputs found

    Palaeoclimate inferred from δ18O and palaeobotanical indicators in freshwater tufa of Lake Äntu Sinijärv, Estonia

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    We investigated a 3.75-m-long lacustrine sediment record from Lake Äntu Sinijärv, northern Estonia, which has a modeled basal age >12,800 cal yr BP. Our multi-proxy approach focused on the stable oxygen isotope composition (δ18O) of freshwater tufa. Our new palaeoclimate information for the Eastern Baltic region, based on high-resolution δ18O data (219 samples), is supported by pollen and plant macrofossil data. Radiocarbon dates were used to develop a core chronology and estimate sedimentation rates. Freshwater tufa precipitation started ca. 10,700 cal yr BP, ca. 2,000 years later than suggested by previous studies on the same lake. Younger Dryas cooling is documented clearly in Lake Äntu Sinijärv sediments by abrupt appearance of diagnostic pollen (Betula nana, Dryas octopetala), highest mineral matter content in sediments (up to 90 %) and low values of δ18O (less than −12 ‰). Globally recognized 9.3- and 8.2-ka cold events are weakly defined by negative shifts in δ18O values, to −11.3 and −11.7 ‰, respectively, and low concentrations of herb pollen and charcoal particles. The Holocene thermal maximum (HTM) is palaeobotanically well documented by the first appearance and establishment of nemoral thermophilous taxa and presence of water lilies requiring warm conditions. Isotope values show an increasing trend during the HTM, from −11.5 to −10.5 ‰. Relatively stable environmental conditions, represented by only a small-scale increase in δ18O (up to 1 ‰) and high pollen concentrations between 5,000 and 3,000 cal yr BP, were followed by a decrease in δ18O, reaching the most negative value (−12.7 ‰) recorded in the freshwater tufa ca. 900 cal yr BP

    Social Relationships and Mortality Risk: A Meta-analytic Review

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    In a meta-analysis, Julianne Holt-Lunstad and colleagues find that individuals' social relationships have as much influence on mortality risk as other well-established risk factors for mortality, such as smoking

    Assessing seasonal variations and aquifer vulnerability in coastal aquifers of semi-arid regions using a multi-tracer isotopic approach: the case of Grombalia (Tunisia)

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    The Grombalia aquifer (NE Tunisia) is an example of an important source of water supply for regional and national development, where the weak controls over abstraction, fertilizer application and waste disposal, coupled with limited knowledge of aquifer dynamics, is causing aquifer over-exploitation and water quality degradation. Assessing the key role of groundwater in water-resources security is therefore of paramount importance to support new actions to preserve water quality and quantity in the long-run. This study presents one of the first investigations targeted at a complete assessment of aquifer dynamics in the Grombalia aquifer. A multi-tracer hydrogeochemical and isotopic (δ2H, δ18O and 3H) approach was used to study the influence of seasonal variation on piezometric levels, chemical and isotopic compositions, and groundwater recharge. A total of 116 samples were collected from private wells and boreholes during three periods in a 1 year monitoring campaign (February–March 2014, September 2014 and February 2015). Results revealed the overall unsuitability of groundwater for drinking and irrigation purposes (NO3 > 50 mg/L in 51% of the wells; EC >1,000 μS/cm in 99% of the wells). Isotopic balance coupled to piezometric investigation indicated the contribution of the shallow aquifer to deep groundwater recharge. The study also revealed the weakness of ‘business as usual’ management practices, highlighting possible solutions to tackle water-related challenges in the Grombalia region, where climate change, population growth and intensive agricultural activities have generated a large gap between demand and available water reserves, hence becoming a possible driver for social insecurity

    WELL.ME - Wellbeing therapy based on real-time personalized mobile architecture, vs. cognitive therapy, to reduce psychological distress and promote healthy lifestyle in cardiovascular disease patients: study protocol for a randomized controlled trial

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    BACKGROUND: There is compelling evidence that psychological factors may have the same or even greater impact on the possibility of adverse events on cardiac diseases (CD) than other traditional clinical risk factors. Anxiety and depression are predictors of short- and long-term adverse outcomes, increased risk for higher rates of in-hospital complications, re-infarction, malignant arrhythmias, and mortality in CD patients. Despite researchers finding that cognitive behavior therapy (CBT) reduced depressive and anxiety symptoms, the fact that such results are maintained only in the short term and the lack of maintenance of the long-term affects the absence of changes in lifestyles, preventing the possibility of a wide generalization of results. Recently wellbeing therapy (WBT) has been proposed as a useful approach to improve healthy lifestyle behaviors and reduce psychological distress. METHODS/DESIGN: The present randomized controlled study will test WBT, in comparison with CBT, as far as the reduction of symptoms of depression, anxiety and psychological distress, and the improvement of lifestyle behaviors and quality of life in cardiac patients are concerned. Moreover, innovations in communication technologies allow patients to be constantly followed in real life. Therefore WBT based on personalized mobile technology will allow the testing of its effectiveness in comparison with usual WBT. DISCUSSION: The present study is a large outpatient study on the treatment of co-morbid depression, anxiety, and psychological distress in cardiac patients. The most important issues of this study are its randomized design, the focus on promotion of health-related behaviors, and the use of innovative technologies supporting patients' wellbeing in real life and in a continuous way. First results are expected in 201
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