Search Results (61)

During the Late Miocene, Bramatherium was the main representative of the giraffid subfamily Sivatheriinae in the Indian Subcontinent, with sparse and uncertain records from adjacent regions. In the present paper, we describe and compare two ossicones of the same individual, unearthed from the Upper Miocene site of Fourka in Chalkidiki Peninsula, Northern Greece, and attribute them with certain confidence to the species Bramatherium perimense. The definite record of Bramatherium so far away from the Indian Subcontinent and in close proximity to the well-known Pikermian sivatheriine Helladotherium duvernoyi enabled us to re-discuss both the intrageneric diversity of Bramatherium and the debatable Bramatherium–Helladotherium taxonomy. Our review allows us (i) to recognize only two Bramatherium species in Asia: the large-sized B. grande and the smaller B. perimense and (ii) to confirm and further support with morphological and biogeographic evidence the synonymy of Helladotherium with Bramatherium. Full article

In the current study, the impact of different acaricide treatments against Varroa (such as amitraz strips, oxalic and formic acid strips impregnated with glycerin, or the sublimation or instillation of oxalic acid) on glycerol residue levels of propolis was investigated. Propolis samples were collected from five beehives located in Chalkidiki (northern Greece), where all mentioned treatments were used and chemically analyzed and compared to control ones. Propolis samples were collected on days 7, 21, and 65 after the application of Varroa treatments, extracted with ethanol/water (70:30), silylated, and then analyzed using GC-MS, showing the predominance of diterpenes. The sublimation of oxalic acid and the amitraz treatment yielded a low glycerol residue (5.12% and 5.09% from 9.98% and 9.19%, respectively) in propolis specimens, while glycerin-impregnated oxalic acid strips led to elevated glycerol percentages (24.30% from 20.51%), unlike the reduced glycerol residues for all other treatments (instillation: 12.60% from 14.48% and glycerin-impregnated formic acid strips: 8.91% from 9.25%) and controls (3.27% from 6.30%). Furthermore, Principal Component Analysis (PCA) and the corresponding biplot illustrated how the sample composition varied across treatments and sampling days, highlighting the chemical constituent categories that most strongly contributed to these distinctions. These findings suggest that the use of glycerol-impregnated strips should be avoided in future beekeeping treatments against varroosis, as they could have a negative impact on the quality of propolis either for nutritional or medicinal applications. Full article

Floods are the biggest hydrometeorological disaster, affecting millions annually. Thus, flood hazard assessment is crucial and plays a pivotal role in rational water management. This study was undertaken to evaluate flood hazards through the application of MCDM methods and a bivariate statistical model integrated with GIS. The methodologies applied were AHP, fuzzy AHP, and the frequency ratio. Eight flood-related criteria were considered—elevation, flow accumulation, geology, slope, land use/land cover (LULC), distance from the drainage network, drainage density, and rainfall index—for the construction of a Flood Hazard Map for each methodology, with the aim to delineate the regions within the study area most prone to flooding. The results demonstrated that around 34% of the Chalkidiki regional unit presents a high and very high hazard to the occurrence of floods. The comparison of the maps generated using DSC demonstrated that all models are capable of delineating high and very high hazard areas with overlap values varying from 0.8 to 0.98. The validation results indicated that the models exhibit sufficient performance in flood hazard mapping with AUC-ROC scores of 66.6%, 65.7%, and 76.5% for the AHP, FAHP, and FR models, respectively. Full article

The Industry 4.0 era has brought significant changes in all areas of everyday life. This development has an impact on employment relations, making evaluation a core aspect of human resource management, especially in education, where new skills and knowledge are important. Thus, the role of educational leaders as managers and evaluators of the educational staff, and especially, the characteristics/skills they should possess for an effective employee evaluation, are essential for a positive work environment. This study explores the qualitative characteristics that the educational unit manager should have to implement formative assessment practices effectively, and specifically, the mediating role of resilience and self-efficacy in the relationship between emotional intelligence and formative assessment. The sample consisted of 258 educational unit managers serving in primary public schools in the prefectures of Pieria, Imathia, Pella, Kilkis, and Chalkidiki, Greece. A self-report questionnaire was administered online using four scales: TEIQue-SF for emotional intelligence, the Multidimensional Teachers’ Resilience Scale, the New Generalized Self-Efficacy Scale, and the Teacher Formative Assessment Practice Scale. The model was evaluated with SPSS.20 and PLS-SEM v. 4.1.0.6. The results indicate that resilience plays the most crucial role in the model, acting as a key mediator between emotional intelligence and formative assessment. While self-efficacy also has a mediating role, it is effective only when combined with resilience, rather than functioning independently. This research’s results suggest a necessity for implementing professional development programs within schools for both educational managers and teachers. These findings have practical implications for in-service training of educational leaders in emotional intelligence and resilience-based HR practices. Full article

Olive fruit fly (Bactrocera oleae) is a pest affecting olive production, causing both qualitative and quantitative damage in all regions of the Mediterranean. This study investigates the spatiotemporal dynamics of olive fruit fly populations obtained from an extensive trap network in five olive-growing regions of Greece—Chalkidiki, Samos, Lesvos, Lasithi, and Chania—over a two-year period (2022–2023). The aim was to understand if and how factors such as variety, temperature, and altitude affect the population of the olive fruit fly. Using Geographical Information System (GIS) tools and spatial analysis, we correlated olive fruit fly numbers with temperature thresholds and altitude categories to analyze different patterns of pest movement. The results show significant variation in population dynamics based on these factors: altitudes, region, and a temperature threshold (at least above 32 °C). These insights are necessary for developing effective and sustainable pest management practices while considering spatial and temporal variability of olive fruit fly movements. Full article

Water scarcity in coastal tourist areas constitutes a critical environmental and socioeconomic sustainability issue. Hence, it is crucial to implement an integrated water resource management and protection plan. In this research, the DPSIR framework is coupled with hydrochemical data on groundwater resources in the fractured aquifer of the Sithonia Peninsula in Chalkidiki, North Greece. Geographical and demographic data, together with morphology, geology, hydrology, and groundwater quality data, were collected and evaluated to categorize the hydrosystem’s driving forces, pressures, states, impacts, and responses. The main pressures that affect groundwater quality in the study area are tourism, geological formation, and land use. Based on the analysis of the DPSIR framework, the absence of a landfill site, the inadequate operation of sewage treatment plants and biological wastewater treatment systems, and tourist activity contribute significantly to the degradation of groundwater quality. Additionally, the fractured rock aquifer develops preferential flow paths to pollutants through preexisting faults, which influence groundwater quality. The hydrochemical analysis of groundwater indicates seawater intrusion in the coastal area. The combination of DPSIR analysis and a water quality index based on ion ratios of groundwater samples identifies high-risk areas of seawater intrusion. Thus, it is essential to reinforce groundwater resources by implementing managed aquifer recharge, limiting unnecessary use of groundwater during the tourist season, and storing surface water during the wet period. Full article

Rhyssoplax olivacea is a common mediterranean chiton that exhibits great geographic distribution characterized by variability in its abiotic parameters. Using morphometric measurements of the valves and radula, as well as the element composition of its tooth types from individuals sampled from five different regions across the Hellenic seas, intraspecific differences were examined. The relationship between the abiotic factors and elemental composition was also investigated. Hierarchical clustering on principal components (HCPC) was employed separately on the radular and valve characteristics to determine whether these traits can distinguish regions in the form of clusters, while canonical correspondence analysis (CCA) with ANOVA testing were used to examine the effect of temperature, depth and salinity on these features. Both datasets resulted in three clusters; however, investigation of the radula appeared to better distinguish populations among the examined regions, differentiating Kymi and Pagasitikos. The morphometrics of the valves distinguished the North Aegean Sea (Chalkidiki) from the other regions. The CCA reported that the depth, minimum temperature and average salinity influenced the elemental composition of the radular teeth, while the depth and maximum temperature explained variation regarding the valve morphometrics. Full article

Modern bioeconomy and sustainability demands lead food technology in the development of novel biobased edible food preservatives. Herein, the development and characterization of novel polysaccharide (xanthan gum and kappa-carrageenan)-based nanoemulgels (NGs) enhanced with essential oil derivatives; pure citral (CT); pure carvacrol (CV); and various CT:CV ratios (25:75, 50:50, and 75:25) are presented. The obtained NGs are applied as active edible coatings for extending the shelf life of Protected Designation of Origin (PDO) green table olives of Chalkidiki. The zeta potential demonstrated the high stability of the treatments, while light scattering measurement and scanning electron microscopy images confirmed the <100 nm droplet size. EC₅₀ indicated high antioxidant activity for all the tested samples. The fractional inhibitory concentration (FIC) confirmed the synergistic effect of NG with a CT:CV ratio at 50:50 against Staphylococcus aureus and at CT:CV ratios 25:75 and 75:25 against E. coli O157:H7. NG coatings with CT:CV ratios at 50:50 and at 25:75 effectively controlled the weight loss at 0.5%, maintained stable pH levels, and preserved the visual quality of green olives on day 21. The synergistic effect between CT and CV was confirmed as they reduced the spoilage microorganisms of yeasts and molds by 2-log [CFU/g] compared to the control and almost 1 log [CFU/g] difference from pure CT and CV-based NGs without affecting the growth of beneficial lactic acid bacteria crucial for fermentation. NGs with CT:CV ratios at 50:50 and at 25:75 demonstrated superior effectiveness in preventing discoloration and maintaining the main sensory attributes. Overall, shelf life extension was achieved in 21 compared to only 7 of the uncoated ones. Finally, this study demonstrates the potential of polysaccharide-based NGs in mixtures of CT and CV for the shelf life extension of fermented food products. Full article

Antimony is one of the world’s scarcest metals and is listed as a Critical Raw Material (CRM) for the European Union. To meet the increasing demand for metals in a sustainable way, one of the strategies that could be implemented would be the recovery of metals as by-products. This would decrease the amount of hazardous materials filling mining dumps. The present study investigates the potential for producing antimony as a by-product at the Olympias separation plant in Northern Greece. This plant works a skarn mineralization that shows interesting amounts of Sb. Boulangerite (Pb₅Sb₄S₁₁) reports on Pb concentrate levels reached 8% in the analyzed product. This pre-enrichment is favorable in terms of boulangerite recovery since it can be separated from galena through froth flotation. Boulangerite distribution in the primary ore is quite heterogeneous in terms of the inclusion relationships and grain size. However, a qualitative assessment shows that the current Pb concentrate grain size is too coarse to successfully liberate a good amount of boulangerite. The use of image analysis and textural assessments is pivotal in determining shape factors and crystal size, which is essential for the targeting of flotation parameters during separation. The extraction of antimony as a by-product is possible through a two-step process; namely, (i) the preliminary concentration of boulangerite, followed by (ii) the hydrometallurgical extraction of the antimony from the boulangerite concentrate. The Olympias enrichment plant could therefore set a positive example by promoting the benefits of targeted Sb extraction as a by-product within similar sulfide deposits within the European territory. Full article

This study deals with the determination of sites suitable for landfill in the Prefecture of Chalkidiki, North Greece, using Boolean logic and Geographic Information Systems (GIS). Landfill siting is an arduous process as it combines environmental, social, and technical factors. Solid waste management is an urgent requirement in tourist sites worldwide. The Prefecture of Chalkidiki is considered a tourist area where volumes of generated waste increase in the summer. The Boolean logic approach was used in the study area to exclude areas not suitable for the establishment of a landfill site and to select areas that meet all the criteria. Nine criteria were selected to create the final map showing areas with the highest suitability for solid waste disposal. According to the Boolean logic method, suitable areas were given a value of one (1), while unsuitable areas were given a value of zero (0). According to the final thematic map of proposed sites, 12.7% of the study area is suitable for landfill construction. The suitable areas identified include pre-existing landfill sites, thus suggesting that the applied method has a high degree of reliability. Full article

Contemporary healthy food issues and food safety concerns induce consumers to become more interested in a healthier diet such as foods reduced in salt. This study explores consumers’ behaviour, attitude, and expectations for the development of a new reduced-salt table olive product from Chalkidiki, an area of Greek. In this context, the main aim of this paper is to investigate the knowledge and attitudes of consumers about health and nutrition, reduced salt consumption, and consumption of Chalkidiki reduced-salt green table olives. Summary statistics and multivariate analysis were performed to examine consumers’ perceptions. The results of the research highlight a remarkable consumer interest in products with reduced salt content. Furthermore, the majority are willing to purchase such foods which is a possible action that can be taken to reduce salt intake. These outcomes emphasise that producing a new reduced-salt table olive product is promising, as the interest of consumers, industries, and the research community has turned to innovative actions that add nutritional value and meet the consumers’ expectations. Full article

The main purpose of the research is to measure the managerial digitalisation cost of the hotel sector in Northern Greece. Taking into consideration the impact of the pandemic crisis on business management and the lack of rich relevant literature, the study focuses on the cost of managerial digitalisation and its possible relationship with certain hotel demographic characteristics, like star ranking, period of operation, size and accommodation type. The population consists of 2187 hotel units, based on the register of the Hellenic Chamber of Hotels and other local associations such as Chalkidiki Hotels Association. Data were collected through a structured questionnaire, registered in Google forms, and sent by e-mail or alternatively via social media like Facebook. The main finding concerns the low amount of investment related to revenue, as the majority of hotel units spend less than 2.5% of their annual turnover on managerial digitalisation. In addition to this, members of hotel groups, seasonal and summer accommodations invest more in the adoption of digital managerial tools. A positive correlation with the number of employees was also detected. As digitalisation cost in the Greek hospitality sector is a completely unexplored scientific field, this is the first effort to deal with it. Furthermore, as Northern Greece is not as popular a tourist destination as other parts of Greece (i.e., the Aegean islands), the present research is a unique attempt to focus on the hotel sector of a less well-known Greek tourist region. Full article

The sustainable management of forest ecosystems is directly linked to the management of forest fires. The increasing occurrence of wildfires has prompted the need for the establishment of infrastructure aimed at addressing them. The placement of anti-fire water reservoirs can address the lack of water intake points. This study introduces a decision support system (DSS) tailored for the optimal allocation of anti-fire water reservoirs in Mediterranean forest ecosystems, ensuring a reliable water supply for firefighting operations. The methodology integrates the analytical hierarchy process (AHP) and the technique of order of preference by similarity to ideal solutions (TOPSIS) methods, facilitating precise location determination through comprehensive criteria analysis. Additionally, the analysis of the forest road network is incorporated to optimize the placement of water reservoirs. In the forest complex of Taxiarchis, Chalkidiki, Greece, 100 potential reservoir sites were identified and prioritized based on factors such as fire risk, proximity to existing water sources, and coverage area using optimal pathways. The study’s findings demonstrate that by establishing 34 water reservoirs, firefighting forces can access a replenishment point within a 5-min travel time. The conclusions underscore the efficacy of this methodology as a valuable decision-making tool for sustainable wildfire prevention planning. This approach contributes to allocating resources judiciously, effectively mitigating the wildfire risk in Mediterranean forest ecosystems, and therefore promoting sustainability. Full article

The research interest for many authors has been focused on the origin, recovery, and exploration of critical metals, including platinum-group elements (PGEs), with the aim of finding new potential sources. Many giant porphyry Cu deposits are well known around the Pacific Rim, in the Balkan–Carpathian system, Himalayas, China, and Malaysia. However, only certain porphyry Cu-Au deposits are characterized by the presence of significant Pd and Pt contents (up to 20 ppm). This contribution provides new analytical data on porphyry-Cu-Au±Pd±Pt deposits from the Chalkidiki Peninsula and an overview of the existing geochemical characteristics of selected porphyry-Cu deposits worldwide in order to define significant differences between PGE-fertile and PGE-poor porphyry-Cu intrusions. The larger Mg, Cr, Ni, Co, and Re contents and smaller LILE elements (Ba and Sr) in fertile porphyry-Cu-Au-(PGE) reflect the larger contribution from the mantle to the parent magmas. In contrast, the smaller Mg, Cr, Ni, Co, and Re contents and larger Ba and Sr in PGE-poor porphyry-Cu-Mo deposits from the Chalkidiki Peninsula (Vathi, Pontokerasia, and Gerakario) and Russia–Mongolia suggest the presence of parent magmas with a more crustal contribution. Although there is an overlap in the plots of those elements, probably due to the evolution of the ore-forming system, consideration of the maximum contents of Mg, Cr, Ni, and Co is proposed. Magnetite which separated from the mineralized Skouries porphyry of Greece showed small negative Eu anomalies (Eu/Eu* ≥ 0.55), reflecting a relatively high oxidation state during the cooling of the ore-forming system. The relatively high, up to 6 ppm (Pd+Pt), and low Cr content towards the transition from the porphyry to epithermal environment, coupled with the occurrence of Pd, Te, and Se minerals (merenskyite, clausthalite), and tetrahedrite–tennantite in fertile porphyry Cu deposits (Elatsite deposit, Bulgaria), reflect a highly fractionated ore-forming system. Thus, in addition to the crustal and mantle recycling, metasomatism, high oxidation state, and abundant magmatic water, other factors required for the origin of fertile porphyry-Cu deposits are the critical degree of mantle melting to release Pt and Pd in the ore-forming fluids and the degree of fractionation, as reflected in the mineral chemistry and geochemical data. Full article

This study aims to demonstrate an integrated methodology for the valorisation of bakery former food products (FFP) as an ingredient of pig feed diets. The methodology involves: conducting a needs analysis and a full path traceability scheme based on Global Standards 1 (GS1) Organisation (Brussels, Belgium) standards, designing digital tools to support the implementation of the traceability scheme, and assessing the valorisation of FFP and, more specifically, of bakery by-products in bakery meal (BM) production, and its implementation in pig feed diet. BM production comprises various bakery by-products, which were collected, unpacked, grinded, and thermally treated. Physicochemical and microbiological analyses were conducted on BM samples, mainly focusing on nutrient composition, and the presence of aflatoxins, mycotoxins, and pathogenic microorganisms. The BM was then fed to finishing pigs (at an inclusion rate of 20% w/w), in parallel to a control group fed with a conventional pig feed diet. The animals in both dietary groups were evaluated for growth performance, and meat samples were analysed for specific quality parameters and sensory characteristics. The results show that the addition of 20% w/w BM does not significantly affect the growth performance or the meat quality of the pigs. Moreover, a sensory evaluation revealed minor differences in the sensory characteristics of the meat samples, denoting that the BM addition does not seem to dwindle the final meat product. Full article