55 research outputs found

    Nitrate stable isotopes and major ions in snow and ice samples from four Svalbard sites

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    Increasing reactive nitrogen (N-r) deposition in the Arctic may adversely impact N-limited ecosystems. To investigate atmospheric transport of N-r to Svalbard, Norwegian Arctic, snow and firn samples were collected from glaciers and analysed to define spatial and temporal variations (1 10 years) in major ion concentrations and the stable isotope composition (delta N-15 and delta O-18) of nitrate (NO3-) across the archipelago. The delta N-15(NO3-) and delta O-18(NO3-) averaged -4 parts per thousand and 67 parts per thousand in seasonal snow (2010-11) and -9 parts per thousand and 74 parts per thousand in firn accumulated over the decade 2001-2011. East-west zonal gradients were observed across the archipelago for some major ions (non-sea salt sulphate and magnesium) and also for delta N-15(NO3-) and delta O-18(NO3-) in snow, which suggests a different origin for air masses arriving in different sectors of Svalbard. We propose that snowfall associated with long-distance air mass transport over the Arctic Ocean inherits relatively low delta N-15(NO3-) due to in-transport N isotope fractionation. In contrast, faster air mass transport from the north-west Atlantic or northern Europe results in snowfall with higher delta N-15(NO3-) because in-transport fractionation of N is then time-limited

    Protocol and Architecture to Bring Things into Internet of Things

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    The Internet of Things (IoT) concept proposes that everyday objects are globally accessible from the Internet and integrate into new services having a remarkable impact on our society. Opposite to Internet world, things usually belong to resource-challenged environments where energy, data throughput, and computing resources are scarce. Building upon existing standards in the field such as IEEE1451 and ZigBee and rooted in context semantics, this paper proposes CTP (Communication Things Protocol) as a protocol specification to allow interoperability among things with different communication standards as well as simplicity and functionality to build IoT systems. Also, this paper proposes the use of the IoT gateway as a fundamental component in IoT architectures to provide seamless connectivity and interoperability among things and connect two different worlds to build the IoT: the Things world and the Internet world . Both CTP and IoT gateway constitute a middleware content-centric architecture presented as the mechanism to achieve a balance between the intrinsic limitations of things in the physical world and what is required from them in the virtual world. Said middleware content-centric architecture is implemented within the frame of two European projects targeting smart environments and proving said CTP's objectives in real scenarios

    Targeting Procrastination Using Psychological Treatments: A Systematic Review and Meta-Analysis

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    Background: Procrastination can be stressful and frustrating, but it seldom causes any major distress. However, for some people, it can become problematic, resulting in anxiety, lowered mood, physical complaints, and decreased well-being. Still, few studies have investigated the benefits of targeting procrastination. In addition, no attempt has previously been made to determine the overall efficacy of providing psychological treatments. Methods: A systematic review and meta-analysis was conducted by searching for eligible records in Scopus, Proquest, and Google Scholar. Only randomized controlled trials comparing psychological treatments for procrastination to an inactive comparator and assessing the outcomes by a self-report measure were included. A random effects model was used to determine the standardized mean difference Hedges g at post-treatment. Furthermore, test for heterogeneity was performed, fail-safe N was calculated, and the risk of bias was explored. The study was pre-registered at Prospero: CRD42017069981. Results: A total of 1,639 records were identified, with 12 studies (21 comparisons, N = 718) being included in the quantitative synthesis. Overall effect size g when comparing treatment to control was 0.34, 95% Confidence Interval [0.11, 0.56], but revealing significant heterogeneity, Q(20) = 46.99, p amp;lt; 0.00, and I-2 = 61.14%, 95% CI [32.83, 84.24]. Conducting a subgroup analysis of three out of four studies using cognitive behavior therapy (CBT) found an effect size g of 0.55, 95% CI [0.32, 0.77], and no longer showing any heterogeneity, Q(4) = 3.92, p = 0.42, I-2 = 0.00%, 95% CI [0.00, 91.02] (N = 236). Risk of publication bias, as assessed by the Eggers test was not significant, z = -1.05, p = 0.30, fail-safe N was 370 studies, and there was some risk of bias as rated by two independent researchers. In terms of secondary outcomes, the self-report measures were too varied to present an aggregated estimate. Conclusions: Psychological treatments seem to have small benefits on procrastination, but the studies displayed significant between-study variation. Meanwhile, CBT was associated with a moderate benefit, but consisted of only three studies. Recommendations for future research are provided, including the use of more valid and reliable outcomes and a screening interview at intake

    Evaluation of the Topography of Surface Sized Eucalyptus Based Papers

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    The surface properties of paper depend not only on the fibrous matrix but also on the final treatment of the paper surface. The present work compares paper samples with two different surface sizing treatments by using AFM and profilometry to assess topography and roughness parameters as well as to evaluate the spreading of the sizing formulation and to estimate sizing agent particle sizes. The results were confronted with dynamic light scattering measurements regarding particle size. This work shows that AFM is a valuable technique to visualize and quantify the effects of sizing on the paper surface. Due to the small amount of surface sizing applied, no significant differences between the surface sized samples and the reference sample (without surface treatment) could be detected in terms of the surface roughness parameters. Nonetheless, those of sample B1 are systematically smaller than those of sample A1
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