496 research outputs found

    Ecological evaluation of transitional and coastal waters: A marine benthic macrophytes-based model

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    A model to estimate the ecological status and identify restoration targets of transitional and coastal waters was developed. Marine benthic macrophytic species (seaweeds, seagrasses) were used to indicate shifts in the aquatic ecosystem from the pristine state with late-successional species (Ecological State Group I) to the degraded state with opportunistic (ESG II) species. The first group comprises species with a thick or calcareous thallus, low growth rates and long life cycles (perennials), whereas the second group includes sheet-like and filamentous species with high growth rates and short life cycles (annuals). Seagrasses were included in the first group, whereas Cyanophyceae and species with a coarsely branched thallus were included in the second group.The evaluation of ecological status into five categories from high to bad includes a cross comparison in a matrix of the ESGs and a numerical scoring system (Ecological Evaluation Index). The model could allow comparisons, ranking and setting of priorities at regional and national levels fulfilling the requirements of the EU Water Frame Directive. A successful application of the model was realized in selected lagoons of the Macedonian and Thrace region (North Greece) and in the Saronic Gulf coastal ecosystems (Central Greece)

    Differences in Acute:Chronic Workload Ratio Preceding Injury Occurrence in United Soccer League Players

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    Professional soccer players are prone to injuries. Training loads (TL), including games, are associated with injury occurrence. Acute:Chronic workload ratio (ACWR), an index of TL, is considered an accurate injury rate metric. In respect to the relationship between injury occurrence and ACWR load obtained using global positioning systems (GPS), little evidence exists in United Soccer League (USL) teams. It is possible high ACWR during the season to lead to injuries. PURPOSE: To investigate the interaction effect of players’ injury status with ACWR of professional soccer players of a USL team. METHODS: In 2019-20, in-season data were gathered from 20 players (Age 26.3 ± 2.7) across six 3-week microcycles. Players’ TL was monitored over 133 training sessions and 40 regular season games using 10-Hz GPS and 400-Hz accelerometer (PlayerTek, Catapult Innovations). All physical, technical, and tactical overload/underload activities consisted of soccer-specific exercises (utilizing possession, small-sided games: 3v3-11v11) and tactical drills (based on coaches’ desired style of play and game-specific situations). ACWR for players’ total load accumulation was calculated for the week’s acute TL prior to injury week by the mean chronic 4-week TL prior to injury week. Injury group include 11 players who got injured during the in-season and 9 that remained healthy. A factorial repeated design in SPSS for injury group (2) and ACWR injury occurrence time (7) was used to examine the interaction effect. RESULTS: Injury group*ACWR injury time was not significant F6,66= .81, p=.56, η2 = .07. CONCLUSION: There was no difference in ACWR index between injured and non-injured players. For every ACWR injury week the injured ones had higher but non-significant ACWR values ranged from .17 to 1.7 than non-injured besides the cycle2/week2 and cycle3/week2. Our findings warrant further investigation with more participants. Possible limitations may include sample size and convenience sample

    Holocene hydroclimatic changes in Northern Peloponnese (Greece) inferred from the multiproxy record of Lake Lousoi

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    This research presents the paleoenvironmental evolution of a drained lake at the Lousoi plateau (northern Peloponnese), for the last 10,000 years, through the study of a 7 m depth core. Analyses conducted on the core include grain size, TOC, TN, pH, EC, total carbonates (), magnetic susceptibility measurements, XRF analysis, and radiocarbon dating. Our paleoenvironmental reconstruction was based on geochemical proxiesrsquo; distribution in the core, combined with sediment physical and textural characteristics and later comparison between additional lacustrine archives from northern Peloponnese. From 10,900 to 7700 cal BP lacustrine, organic-rich deposits were recognized, reflecting increased lake water levels. Wet climatic conditions seem to have prevailed during this phase, interrupted by a dry pulse at 9400 cal BP. Transition to more shallow waters was marked at 8200 cal BP due to increased sediment deposition in the lake, with the environmental status shifting to a more oxygenated phase. Overall, wet conditions prevailed in this period and are in good agreement with regional records. In the Late Holocene period, the lake seems to have been highly affected by pedogenic processes, and thus, it was difficult to distinguish paleoclimatic/paleoenvironmental signals.1. Introduction 2. Study Area 2.1. Regional Setting 2.2. Geological Setting 3. Materials and Methods 3.1. Coring Fieldwork 3.2. Sedimentology 4. Results 4.1. Core Description and Stratigraphy 4.2. Radiocarbon Dating and Age–Depth Model 4.3. Distribution of Geochemical Proxies 5. Discussion 5.1. Early Holocene (11,800–8200 cal BP) 5.2. Middle Holocene (8200–4200 cal BP) 5.3. Late Holocene (4200 cal BP–Present) 6. Conclusion

    Corporate Social Responsibility in a context of sustainable development

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    “The future we want”, the main document summarizing the action areas advocated by the Rio+20 conference (Rio de Janeiro, Brazil, June 20-22nd), advocates “green economy” as a main instrument to eradicate poverty, while maintaining the healthy functioning of the environment. “Green economy” is a reply to global capitalism and the excesses of its elite practitioners, as they became manifest during the recent economic crisis. A classical contribution of the private business sector to sustainable development is corporate social responsibility (CSR). The concept dovetails in the doctrine that a company is not only responsible for a positive economic performance, but also has to take care about the environmental, social and ethical aspects of its activities. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3164

    ‘The International Teacher Leadership project,’ a case of international action research.

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    Copyright CARNThe paper arises from the International Teacher Leadership project, a research and development project involving researchers and practitioners in 14 European countries. The paper provides a conceptual exploration of the idea of teacher leadership and its role in educational reform, central to which is the idea that teachers, regardless of their level of power and organisational position, can engage in the leadership of enquiry-based development activity aimed at influencing their colleagues and embedding improved practices in their schools. The paper provides an outline of the project’s methodology which builds on that used in the Carpe Vitam Leadership for Learning project (Frost, 2008a). It is a form of collaborative action research which is highly developmental and discursive. It seeks to identify principles, strategies and tools that can be applied in a range of cultural settings. The paper includes a thematic analysis of the cultural contexts and policy environments of the participating countries in order to identify the obstacles to teacher leadership and to inform the nature of the support strategies employed

    Determination of environmental flows in rivers using an integrated hydrological-hydrodynamic-habitat modelling approach

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    [EN] We propose the novel integrated modelling procedure 3H-EMC for the determination of the environmental flow in rivers and streams; 3H-EMC combines Hydrological, Hydrodynamic and Habitat modelling with the use of the Environmental Management Classes (EMCs) that are defined by the Global Environmental Flow Calculator. We apply 3H-EMC in the Sperchios River in Central Greece, in which water abstractions for irrigation cause significant environmental impacts. Calculations of the hydrodynamic-habitat model, in which the large and the small chub are the main fish species, suggest discharge values that range from 1.0 m3/s to 4.0 m3/s. However, hydrological modelling indicates that it is practically difficult to achieve discharges that are higher than approximately 1.0-1.5 m3/s. Furthermore, legislation suggests significantly lower values (0.4-0.5 m3/s) that are unacceptable from the ecological point of view. This behaviour shows that a non-integrated approach, which is based only on hydrodynamic-habitat modelling does not necessarily result in realistic environmental flows, and thus an integrated approach is required. We propose the value of 1.0 m3/s as the "optimum" environmental flow for Sperchios River, because (a) it satisfies the habitat requirements, as expressed by the values of weighted useable area that are equal to 2180 and 1964 m2 for the large and small chub, respectively, and correspond to 82 and 95% of their respective maximum values, (b) it is consistent with the requirements of Environmental Classes A and B, whose percentiles are higher than 75% for discharge (77.2%) and for habitat availability (>83.5% for the large chub and >85.0% for the small chub), (c) it is practically achievable from the hydrological point of view, and (d) it is higher than the value proposed by the Greek legislation. The proposed modelling approach can be applied to any river or stream using the same or similar modelling tools, which should be linked via suitable coupling algorithms.Hydraulic field measurements were performed within the framework of a research project by the Hellenic Centre of Marine Research (HCMR) entitled KRIPIS “Development of an integrated management system for river basin, coastal and marine zones” (http://imbriw.hcmr.gr/en/). Fish habitat data were collected within the framework of the ECOFLOW research project (www. ecoflow.gr). A part of the modelling work has been performed, while the first author was a visiting professor at the Technical University of Munich (TUM); thanks are due to the Bavarian State Ministry of Education and Cultural Affairs and the German Academic Exchange Service (DAAD).Stamou, A.; Polydera, A.; Papadonikolaki, G.; Martinez-Capel, F.; Muñoz Mas, R.; Papadaki, C.; Zogaris, S.... (2018). Determination of environmental flows in rivers using an integrated hydrological-hydrodynamic-habitat modelling approach. Journal of Environmental Management. 209:273-285. https://doi.org/10.1016/j.jenvman.2017.12.038S27328520
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