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Social media reveals consistently disproportionate tourism pressure on a threatened marine vertebrate
Establishing how wildlife viewing pressure is distributed across individual animals within a population can inform the management of this activity, and ensure targeted individuals or groups are sufficiently protected. Here, we used social media data to quantify whether tourism pressure varies in a loggerhead sea turtle Caretta caretta population and elucidate the potential implications. Laganas Bay (Zakynthos, Greece) supports both breeding (migratory, and hence transient) and foraging (resident) turtles, with turtle viewing representing a major component of the tourism industry. Social media entries spanning two seasons (April to November, 2018 and 2019) were evaluated, and turtles were identified via photo-identification. For the 2 years, 1684 and 2105 entries of 139 and 122 unique turtles were obtained from viewings, respectively (boats and underwater combined). However, while residents represented less than one-third of uniquely identified turtles, they represented 81.9 and 87.9% of all entries. Even when the seasonal breeding population was present (May to July), residents represented more than 60% of entries. Notably, the same small number of residents (<10), mostly males, were consistently viewed in both years; however, different individuals were targeted by boats versus underwater. Thus, turtles appear to remain in the area despite high viewing intensity, possibly indicating low disturbance. However, photo-identification records revealed a high risk of propeller and boat strike to residents (30%) leading to trauma and mortality. To reduce this threat, we recommend the compulsory use of propeller guards for all boats, compliance with speed regulations and the creation of temporary ârefugeâ zones for resident animals at viewing hotspots, with these suggestions likely being relevant for other wildlife with similar population dynamics. In conclusion, social media represents a useful tool for monitoring individuals at a population scale, evaluating the pressure under which they are placed, and providing sufficient data to refine wildlife viewing guidelines and/or zoning. Š 2020 The Authors. Animal Conservation published by John Wiley & Sons Ltd on behalf of Zoological Society of Londo
A physicochemical study of Medieval and Post-Medieval ceramics from the Aegean
The archaeological excavations carried out in Greece at Chalcis, the Athenian Agora and the Castle of Mytilene in Lesvos have resulted in the accumulation of a large collection of Medieval and Post-Medieval glazed pottery vessels and sherds that is unparalleled in the Aegean region and that is a perfect basis for archaeometrical researchâ . This thesisâ objective is to analyse 245 ceramic samples from these three excavated sites in Greece with the most advanced technological methods applying an integrated analytical methodology that took into account compositional data of ceramic body, slip, glaze and pigmentsâ . This study attempts to investigate both the provenance as well as the glazed pottery techniques and their development through timeâ . The chosen ceramic samples were examined using a number of archaeometrical techniques such as Optical Microscopy (OM), X-Ray Fluorescence Spectroscopy (pXRF, WDXRF), Petrographic analysis, X-Ray Diffraction Spectroscopy (XRD), Scanning Electron Microscopy (SEM-EDS) and Raman Spectroscopyâ . These archaeological sites distinguish from others in the (eastern) Mediterranean where glazed pottery manufacture has been confirmedâ . The glazed pottery assemblages in these cities clearly demonstrate a changing industry as they date from the Early Byzantine to the Early Modern periodsâ . This PhD research was financially supported in part by the Scholarship of the âPrins Bernhard Cultuurfondsâ, and in part by the Institute of Nanoscience and Nanotechnology of the National Centre for Scientific Research Ę˝DemokritosĘź in Greeceâ .Archaeology of the Near Eas
Coalition Resilient Outcomes in Max k-Cut Games
We investigate strong Nash equilibria in the \emph{max -cut game}, where
we are given an undirected edge-weighted graph together with a set of colors. Nodes represent players and edges capture their mutual
interests. The strategy set of each player consists of the colors. When
players select a color they induce a -coloring or simply a coloring. Given a
coloring, the \emph{utility} (or \emph{payoff}) of a player is the sum of
the weights of the edges incident to , such that the color chosen
by is different from the one chosen by . Such games form some of the
basic payoff structures in game theory, model lots of real-world scenarios with
selfish agents and extend or are related to several fundamental classes of
games.
Very little is known about the existence of strong equilibria in max -cut
games. In this paper we make some steps forward in the comprehension of it. We
first show that improving deviations performed by minimal coalitions can cycle,
and thus answering negatively the open problem proposed in
\cite{DBLP:conf/tamc/GourvesM10}. Next, we turn our attention to unweighted
graphs. We first show that any optimal coloring is a 5-SE in this case. Then,
we introduce -local strong equilibria, namely colorings that are resilient
to deviations by coalitions such that the maximum distance between every pair
of nodes in the coalition is at most . We prove that -local strong
equilibria always exist. Finally, we show the existence of strong Nash
equilibria in several interesting specific scenarios.Comment: A preliminary version of this paper will appear in the proceedings of
the 45th International Conference on Current Trends in Theory and Practice of
Computer Science (SOFSEM'19
Water and protein dynamics in protein-water mixtures over wide range of composition
Š 2012 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] Water and protein dynamics in two globular protein-water systems, water-lysozyme
and water-BSA (bovine serum albumine), were studied by differential scanning calorimetry (DSC), dielectric relaxation spectroscopy (DRS) and thermally stimulated depolarization currents (TSDC) techniques. Water equilibrium sorption isotherms (ESI) measurements were also recorded at room temperature. The samples covered a wide range of composition, from practically dry solid pellets (2wt% of water) to dilute solutions (82wt% of water). Crystallization and melting events of water were studied by DSC and the amount of uncrystallized water was calculated. The evolution of dynamics with hydration level was followed for various dielectric relaxation processes, the emphasis being given to relaxation processes of polar groups on the surface of the proteins and of uncrystallized water molecules. A relationship between the formation of a conductive percolating water cluster and the saturation of the water process was found.This research has been co-financed by the European Union (European Social Fund - ESF) and Greek national funds through the Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) - Research Funding Program: Heracleitus II. Investing in knowledge society through the European Social Fund.Kyritsis, A.; Panagopoulou, A.; Pissis, P.; Sabater I Serra, R.; GĂłmez Ribelles, JL.; Shinyashiki, N. (2012). Water and protein dynamics in protein-water mixtures over wide range of composition. IEEE Transactions on Dielectrics and Electrical Insulation. 19(4):1239-1246. https://doi.org/10.1109/TDEI.2012.6259997S1239124619
Ancient Egyptian Blue (CaCuSi4O10) Pigment by Modern Solution Combustion Synthesis Method
The Egyptian blue pigment, CaCuSi4O10, has been used in ancient Egypt from 3000 BC. This pigment consists of CaCuSi4O10Â with variable amounts of wollastonite (CaSiO3), high amount of Cu oxides, cuprite (Cu2O) or tenorite (CuO). It was prepared by melting the high percentage of copper in association with lime and desert sand in the Ancient time. In this work Egyptian blue was produced by solution combustion synthesis (SCS) in homogeneous aqueous solution of composition: cupper and calcium nitrates, sodium silicate and urea. This method permits chemically stable Egyptian blue fast and economic production. The Egyptian blue composition and structure obtained after SCS and calcination were studied by XRD, FTIR and SEM/EDX analysis. Crystallite size and crystal lattice parameters were calculated. An increase in combustion temperature during SHS and calcinations temperature influence Egyptian blue yield and crystallite size, slightly influence parameters of crystal lattice
Production technology of glazed pottery in Chalcis, Euboea, during the Middle Byzantine period
This paper focuses on various categories of glazed pottery, which were in circulation in western Euboea (Greece) during the Middle Byzantine and Late Byzantine periods. The production technology and particularly the surface treatment of Byzantine glazed pottery have been investigated on the basis of 56 ceramic fragments from a rescue excavation in Orionos street in Chalkis, Euboea. This paper focuses on the manufacture of glazed pottery within the local pottery repertoire of Chalkis, while trying to contextualise the pottery typology and to consider the issues of technology. The chemical analysis by non-invasive energy dispersive X-ray fluorescence (XRF) and Scanning electron microscopy (SEM-EDS) provided information about the compositional variation of the examined glazed ceramics assemblage. Moreover, sections of the samples were examined by optical microscopy and scanning electron microscopy (SEM) in order to determine the microstructure of the samples, as well as the vitrification and the porosity of the ceramic body. Finally, X-ray diffraction (XRD) was applied for qualitative mineralogical analysis indicating presence or absence of high temperature phases and information about firing conditions.Roman Provinces, Middle Ages and Modern Perio
Associations of physician burnout with career engagement and quality of patient care: systematic review and meta-analysis.
To examine the association of physician burnout with the career engagement and the quality of patient care globally. Systematic review and meta-analysis. Medline, PsycINFO, Embase, and CINAHL were searched from database inception until May 2021. Observational studies assessing the association of physician burnout (including a feeling of overwhelming emotional exhaustion, feelings of cynicism and detachment from job defined as depersonalisation, and a sense of ineffectiveness and little personal accomplishment) with career engagement (job satisfaction, career choice regret, turnover intention, career development, and productivity loss) and the quality of patient care (patient safety incidents, low professionalism, and patient satisfaction). Data were double extracted by independent reviewers and checked through contacting all authors, 84 (49%) of 170 of whom confirmed their data. Random-effect models were used to calculate the pooled odds ratio, prediction intervals expressed the amount of heterogeneity, and meta-regressions assessed for potential moderators with significance set using a conservative level of P<0.10. 4732 articles were identified, of which 170 observational studies of 239â246 physicians were included in the meta-analysis. Overall burnout in physicians was associated with an almost four times decrease in job satisfaction compared with increased job satisfaction (odds ratio 3.79, 95% confidence interval 3.24 to 4.43, I =97%, k=73 studies, n=146â980 physicians). Career choice regret increased by more than threefold compared with being satisfied with their career choice (3.49, 2.43 to 5.00, I =97%, k=16, n=33â871). Turnover intention also increased by more than threefold compared with retention (3.10, 2.30 to 4.17, I =97%, k=25, n=32â271). Productivity had a small but significant effect (1.82, 1.08 to 3.07, I =83%, k=7, n=9581) and burnout also affected career development from a pooled association of two studies (3.77, 2.77 to 5.14, I =0%, n=3411). Overall physician burnout doubled patient safety incidents compared with no patient safety incidents (2.04, 1.69 to 2.45, I =87%, k=35, n=41â059). Low professionalism was twice as likely compared with maintained professionalism (2.33, 1.96 to 2.70, I =96%, k=40, n=32â321), as was patient dissatisfaction compared with patient satisfaction (2.22, 1.38 to 3.57, I =75%, k=8, n=1002). Burnout and poorer job satisfaction was greatest in hospital settings (1.88, 0.91 to 3.86, P=0.09), physicians aged 31-50 years (2.41, 1.02 to 5.64, P=0.04), and working in emergency medicine and intensive care (2.16, 0.98 to 4.76, P=0.06); burnout was lowest in general practitioners (0.16, 0.03 to 0.88, P=0.04). However, these associations did not remain significant in the multivariable regressions. Burnout and patient safety incidents were greatest in physicians aged 20-30 years (1.88, 1.07 to 3.29, P=0.03), and people working in emergency medicine (2.10, 1.09 to 3.56, P=0.02). The association of burnout with low professionalism was smallest in physicians older than 50 years (0.36, 0.19 to 0.69, P=0.003) and greatest in physicians still in training or residency (2.27, 1.45 to 3.60, P=0.001), in those who worked in a hospital (2.16, 1.46 to 3.19, P<0.001), specifically in emergency medicine specialty (1.48, 1.01 to 2.34, P=0.042), or situated in a low to middle income country (1.68, 0.94 to 2.97, P=0.08). This meta-analysis provides compelling evidence that physician burnout is associated with poor function and sustainability of healthcare organisations primarily by contributing to the career disengagement and turnover of physicians and secondarily by reducing the quality of patient care. Healthcare organisations should invest more time and effort in implementing evidence-based strategies to mitigate physician burnout across specialties, and particularly in emergency medicine and for physicians in training or residency. PROSPERO number CRD42021249492. [Abstract copyright: Š Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.
Overcoming job demands to deliver high quality of care in the hospital setting across Europe: the role of teamwork and positivity
Health care professionals deal on a daily basis with several job demands â emotional, cognitive, organizational and physical. They must also ensure high quality care to their patients. The aim of this study is to analyse the impact of job demands on quality of care and to investigate team (backup behaviors) and individual (positivity ratio) processes that help to shield that impact. Data was collected from 2,890 doctors and nurses in 9 European countries by means of questionnaires. Job demands have a negative impact on the quality of care delivered by health professionals. Backup behaviors had a mediating effect between job demands and quality of care. Also, the positivity ratio of professionals (ratio of positive and negative emotions experienced) was also found as a significant mediator between most job demands and quality of care dimensions. Finally, we found a double mediation between most job demands and quality of care, where backup behaviors influenced the positivity ratio. Quality of care in hospitals is closely related to job demands. Hospital managers should consider the importance of cooperation within health care professionalsâ teams and ought to find ways to develop teamwork in order to promote patientsâ safety
Mediterranean sea turtles: Current knowledge and priorities for conservation and research
This is the final version. Available on open access from Inter Research via the DOI in this recordThe available information regarding the 2 sea turtle species breeding in the Mediterranean (loggerhead turtle Caretta caretta and green turtle Chelonia mydas) is reviewed, including biometrics and morphology, identification of breeding and foraging areas, ecology and behaviour, abundance and trends, population structure and dynamics, anthropogenic threats and conservation measures. Although a large body of knowledge has been generated, research efforts have been inconsistently allocated across geographic areas, species and topics. Significant gaps still exist, ranging from the most fundamental aspects, such as the distribution of major nesting sites and the total number of clutches laid annually in the region, to more specific topics like age at maturity, survival rates and behavioural ecology, especially for certain areas (e.g. south-eastern Mediterranean). These gaps are particularly marked for the green turtle. The recent positive trends of nest counts at some nesting sites may be the result of the cessation of past exploitation and decades of conservation measures on land, both in the form of national regulations and of continued active protection of clutches. Therefore, the current status should be considered as dependent on such ongoing conservation efforts. Mitigation of incidental catch in fisheries, the main anthropogenic threat at sea, is still in its infancy. From the analysis of the present status a comprehensive list of re search and conservation priorities is proposed.C.C. is supported
by the project CTM2013-48163 of the Spanish Ministry of
Economy and Competitivity. The Cyprus Wildlife Society
(CWS) acknowledges the financial support of the Department
of Fisheries and Marine Research of the Government
to the CWS for the implementation of the Turtle Conservation
Project in the period 2010â2016 and for all its assistance
to the Society in previous years. J.T. is supported by project Prometeo
II (2015-018) of the Generalitat Valenciana and projects
MEDSEALITTER-INTERREG and INDICIT of the European
Union
On a Simple Hedonic Game with Graph-Restricted Communication
International audienceWe study a hedonic game for which the feasible coalitions are prescribed by a graph representing the agents' social relations. A group of agents can form a feasible coalition if and only if their corresponding vertices can be spanned with a star. This requirement guarantees that agents are connected, close to each other, and one central agent can coordinate the actions of the group. In our game everyone strives to join the largest feasible coalition. We study the existence and computational complexity of both Nash stable and core stable partitions. Then, we provide tight or asymptotically tight bounds on their quality, with respect to both the price of anarchy and stability, under two natural social functions, namely, the number of agents who are not in a singleton coalition, and the number of coalitions. We also derive refined bounds for games in which the social graph is restricted to be claw-free. Finally, we investigate the complexity of computing socially optimal partitions as well as extreme Nash stable ones
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