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In the northern part of the Dehaj-Sarduieh volcano-plutonic belt (Deh-Zahir area, Kerman province, Iran), a series of subvolcanic rocks occur as dykes. These dykes show variable porphyritic textures and contain large plagioclase, clinopyroxene, K-feldspar and occasionally altered olivine phenocrysts set in an intergranular and trachytic textured groundmass. The groundmass consists of olivine, clinopyroxene, plagioclase, K-feldspar, analcime and opaque crystals. Electron microprobe analyses reveal that the plagioclases are mainly bytownite, K-feldspars are sanidine and pyroxenes are diopside and salite. Based on geochemical data, these rocks are classified as trachy-basalts with shoshonitic affinity, with primitive mantle-normalized spider diagrams showing clear depletions in Nb, Ti, and heavy rare earth elements (HREE) + Y and a strong enrichment in large-ion lithophile elements (LILE). Chondrite-normalized REE diagrams for these rocks show light REE enrichment, but heavy REE + Y are less, without any remarkable Eu anomaly. Primitive 87Sr/86Sr ratios and positive εNd values for the studied dykes change from 0.70438 to 0.70550 and 2.09 to 5.76, respectively, of which these were derived from parental magma extracted from partial melting of metasomatized mantle, namely spinel peridotite. However minor contamination with upper crust was also involved in the composition of the studied dykes. Tectonomagmatic discrimination diagrams and zircon U-Pb age data show that the Deh-Zahir dykes formed after collision of the Arabian and Eurasian plates in the Miocene. published

Purpose The investigation of zirconia core surface pretreatments on the flexural strength of bilayered zirconia ceramics before and after artificial accelerating aging. Methods Ninety bar-shaped specimens were manufactured from Yttria Stabilized Tetragonal Zirconia Polycrystal (Y-TZP) and divided in three groups depending on zirconia surface pretreatment before veneering: layering with liner, pretreatment with silane-containing gas flame (SGF) with the Silano-Pen device and alumina air-abrasion. Half of the veneered specimens in each group (n=15) underwent artificial accelerating aging. A 4-point bending test was performed to determine flexural strength. Three specimens from each group were further analyzed using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) before veneering and after fracture (aged and non-aged subgroups). Results Alumina air-abrasion was correlated to increased phase transformation from tetragonal to monoclinic zirconia phase. Qualitative analysis revealed that with the majority of the specimens pretreated with the silane-containing gas flame, areas of the veneering material remained firmly attached to the zirconia core after flexural strength testing. There was no statistically significant difference on the flexural strength among the groups before or after aging. Artificial accelerating aging resulted in statistically significant higher flexural strength of the specimens after aging. Conclusion SGF pretreatment can be an acceptable and feasible alternative method before the veneering of Y-TZP zirconia as it presented slightly higher bond strength compared with alumina air-abrasion which was associated with higher tetragonal to monoclinic (t→m) phase transformation. Accelerating aging leads to an increase of the mechanical properties under in vitro conditions.

The increasing volume of plastics from waste electric and electronic equipment (WEEE) nowadays is of major concern since the various toxic compounds that are formed during their handling enhance the difficulties in recycling them. To overcome these problems, this work examines solvent extraction as a pretreatment method, prior to thermochemical recycling by pyrolysis. The aim is to remove bromine from some polymeric blends, with a composition that simulates WEEE, in the presence of tetrabromobisphenol A (TBBPA). Various solvents—isopropanol, ethanol and butanol—as well as several extraction times, were investigated in order to find the optimal choice. Before and after the pretreatment, blends were analysed by X-ray fluorescence (XRF) to estimate the total bromine content. Blends were pyrolyzed before and after the soxhlet extraction in order to evaluate the derived products. FTIR measurements of the polymeric blends before and after the soxhlet extraction showed that their structure was maintained. From the results obtained, it was indicated that the reduction of bromine was achieved in all cases tested and it was ~34% for blend I and ~46% and 42% for blend II when applying a 6 h soxhlet with isopropanol and ethanol, respectively. When using butanol bromine was completely eliminated, since the reduction reached almost 100%. The latter finding is of great importance, since the complete removal of bromine enables the recycling of pure plastics. Therefore, the main contribution of this work to the advancement of knowledge lies in the use of a solvent (i.e., butanol) which is environmentally friendly and with a high dissolving capacity in brominated compounds, which can be used in a pretreatment stage of plastic wastes before it is recycled by pyrolysis.

Zircon grains are reasonably ubiquitous in river banks and beach placers as detrital minerals, including along the ~1700 km long Indian east coast, from Odisha state to the state of Kerala. Zircons from beach placers and river banks located along the eastern part of Odisha, India, were studied using LA-ICP-MS in order to delineate their geochemical characteristics. Hf (mean = 11270 ppm) and Y (mean = 1064 ppm) were the two most abundant trace elements found within zircon grains as compared to other trace elements. The abundance of uranium was observed to be 2–4 times larger than that of thorium. Zircon overgrowths formed in equilibrium with a partial melt and were similar to magmatic zircon in terms of the high Y, Hf and P content, steep heavy-enriched REE pattern, positive Ce anomaly and negative Eu anomaly. The average low Th/U ratio of the studied zircon grains distinguished them from the magmatic ones. The REE present in zircon grains was restricted to high-grade metamorphic events. The result of the present study would be useful for delineating the source region and the efficacy of resource potential and indigenous export.

Independent and free media are considered to be an essential component of any democratic society. Especially in countries that have been hit hard by the economic crisis and austerity measures, such as Greece, the need for independent journalism to act as watchdog, on behalf of civil society is more important than ever. However, the clientelistic relationships upon which the whole Greek media landscape is built, leaves little room for a journalism that investigates, exposes and holds those in power accountable. It is within this context, we argue, that alternative web radio stations are emerging, taking advantage of the internet technology in order to create bottom-up journalistic initiatives that challenge the current narratives and seek to constitute a new paradigm of journalism. This paper sets out to examine the general characteristics of the Greek media ecosystem but also goes on to examine the particular conditions that led to the current media crisis. It also discusses the legislative framework surrounding Greek media. Finally, this paper aims to provide a brief overview of the alternative web radios that have emerged in the current media ecosystem, by presenting in three Greek alternative web radio stations, describing their basic characteristics, principles, structures and their views on journalistic practices. Palabras clave: media transparency, radio, television, web radio.

Waste electric and electronic equipment (WEEE) has increased enormously because of the rapid expansion and consumption of electronic devices and their short lifespan. Recycling of WEEE is challenging, due to the presence of various materials including glass, metals and plastics (Buekens and Yang 2014). Brominated flame retardants (BFR), such as tetrabromobisphenol A (TBBPA) that are often added into plastics are toxic substances that must be removed before or during recycling (Ma et al. 2016). Pyrolysis is an environmentally friendly method, since secondary valuable materials or monomers can be recovered (Antonakou et al. 2014). In this work solvent extraction prior to pyrolysis is examined as a pretreatment method, in order to reduce the bromine content in specific brominated-polymeric blends. The blends consist of acrylonitrile-butadiene-styrene (ABS), high-impact polystyrene (HIPS), polycarbonate (PC) and polypropylene (PP), along with TBBPA, which is the tested BFR. Different solvents as well as different extraction times were investigated. Before and after pretreatment, blends were analysed by X-ray fluorescence (XRF) so as to estimate the bromine content; and were also pyrolysed in order to evaluate the derived products and examine if brominated compounds continue to form. XRF and pyrolysis experiments indicate that reduction of bromine can be effectively achieved.

Across the globe, governments have issued emergency and drastic measures aimed at tracking the spread of COVID-19 and safeguarding public health. Notwithstanding the necessity and importance of som...

The article looks to identify and contextualise the shift of journalism towards emotion in terms of broader socio-political shifts. It focuses on ‘hate journalism’, a term we use to describe a new kind of journalism that emerged in Greece during the debt crisis years and is ideologically close to neo-fascist, and ethnonationalist political positions. We understand hate as an action oriented socio-cultural practice and examine the conditions of production and deployment of hate through focusing on Makeleio, the most successful example of this kind of journalism. Within this context, hate is produced and circulated as a ‘hook’ to attract and entice users, by mirroring their emotions; it further constitutes a means of producing and diffusing ideology by helping readers manage uncertainty through putting forward authoritarian solutions. In doing so, hate journalism is involved in social reproduction processes by which (Greek) society produces and sustains itself as ethnically pure, culturally Christian, and gendered as masculine and virile. Readers are invited to recognise themselves and their practices and vernacular, to be consoled and offered solace and comfort within an unmoored world. They, in turn, offer support to this journalism through consuming it.

This article explores Greek alternative media, records their hybridity and analyses them under the prism of political economy. Drawing theoretically on researchers who emphasize the elusiveness and heterogeneity of alternative media and examining them on account of their ownership structures, production practices and media content, I propose their conceptualization as a vibrant organism in a constant dialectic relationship with mainstream media. These ‘alternative hybrid media’ may borrow people, ideas and practices from mainstream media, but they do not compromise their values for the pursuit of profit or political power. This article focuses on Efimerida ton Syntakton, the country’s first national cooperative newspaper, which emerged out of a collective of laid-off journalists and constitutes a representative example of the hybridity that characterizes the Greek alternative media ecosystem. Based on interviews with journalists and secondary data, this article aims to point to the defining characteristics of ‘alternative hybrid media’ and generate a deeper insight into the complex area of alternative media.

To design, develop and study a novel drug delivery system for intraocular applications. The spin coating technique was applied to develop a polymeric, drug‐eluting thin film consisting of a blend of organic polymers [poly (D, L lactide coglycolide) lactide: glycolide 75: 25, PLGA and polycaprolactone, PCL] and dexamethasone on the surface of intraocular lenses (IOLs). The initial durability of the IOLs during spinning was assessed. Information about the structural and optical properties of the modified IOLs was extracted using atomic force microscopy, scanning electron microscopy and spectroscopic ellipsometry. A drug release study was conducted for 8 weeks. The IOLs were durable in spinning speeds higher than the ones used to develop thin films. Single‐layer thin films were successfully developed on the optics and the haptics of the lenses. The films formed nanopores with encapsulated aggregates of dexamethasone. The spectroscopic ellipsometry showed an acceptable optical transparency of the lenses regardless of the deposition of the drug‐eluting films on their surface. The drug release study demonstrated gradual dexamethasone release over the selected period. In conclusion, the novel drug‐eluting IOL system exhibited desired properties regarding its transparency and drug release rate. Further research is necessary to assess their suitability as an intraocular drug delivery system.

In the present study, rough emerald single crystals and rough emeralds in the host rock from the ruins of Alexandria and from the Mount Zabargad in Egypt, preserved in the collection of the museum of the Ecole des Mines (Mines Paris—PSL) since the late 19th or early 20th century, are investigated. All samples were characterized by non-destructive spectroscopic and chemical methods during a week-long loan to the LFG. Raman, FTIR and UV-Vis-NIR spectroscopy revealed that Egyptian emeralds contain H2O molecules accompanied by relatively high concentrations of alkali ions and are colored by chromium and iron. Additionally, EDXRF showed that the emeralds from Egypt contain up to 84 ppm Rb and low amounts (below 200 ppm) of Cs. Inclusions and parts of the host rock were also observed under optical microscope and analyzed with Raman spectroscopy. Tube-like structures, quartz, calcite, dolomite, albite and phlogopite are associated minerals, and inclusions are identified in these historic emeralds from Egypt. This work will hopefully further contribute to the characterization of emeralds of archaeological significance.

The investigation of zirconia core surface pretreatments on the flexural strength of bilayered zirconia ceramics before and after artificial accelerating aging.Ninety bar-shaped specimens were manufactured from Yttria Stabilized Tetragonal Zirconia Polycrystal (Y-TZP) and divided in three groups depending on zirconia surface pretreatment before veneering: layering with liner, pretreatment with silane-containing gas flame (SGF) with the Silano-Pen device and alumina air-abrasion. Half of the veneered specimens in each group (n=15) underwent artificial accelerating aging. A 4-point bending test was performed to determine flexural strength. Three specimens from each group were further analyzed using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) before veneering and after fracture (aged and non-aged subgroups).Alumina air-abrasion was correlated to increased phase transformation from tetragonal to monoclinic zirconia phase. Qualitative analysis revealed that with the majority of the specimens pretreated with the silane-containing gas flame, areas of the veneering material remained firmly attached to the zirconia core after flexural strength testing. There was no statistically significant difference on the flexural strength among the groups before or after aging. Artificial accelerating aging resulted in statistically significant higher flexural strength of the specimens after aging.SGF pretreatment can be an acceptable and feasible alternative method before the veneering of Y-TZP zirconia as it presented slightly higher bond strength compared with alumina air-abrasion which was associated with higher tetragonal to monoclinic (t→m) phase transformation. Accelerating aging leads to an increase of the mechanical properties under in vitro conditions.

Between the southern margin of the European loess belt and Sahara Desert, thin and irregularly distributed loess deposits occur in Mediterranean mountains. During the most recent deglaciation, along the Pleistocene-Holocene boundary, the deposition of glacial, periglacial and outwash sediments, was the main local source of Mediterranean alpine loess, whereas proximal alluvial planes comprised a secondary source. The mid-Holocene termination of African Humid Period and subsequent aridification of Sahara Desert occurred simultaneously with a change of the regional climate from Atlantic to Mediterranean-dominated, characterized by frequent episodes of southerly winds. This resulted to a change of the loess source, as deflation of quartz rich silts enriched in Zr during intense episodes of Sahara dust transport became more dominant. Here, a 32cm loess profile from the Plateau of Muses (PM), below the summit of Mount Olympus, Greece, is investigated on the basis of grain size, mineralogy, environmental magnetism and geochemistry. Comparisons of loess samples with glacial and periglacial deposits, enables us to differentiate relative contributions of local sources and allochthonous aeolian inputs. Calcite sand rich in feldspars makes up the glacial and periglacial clast free matrix. In contrast, PM loess is composed by clay and fine silt fractions with minor calcite sand contributions. The mineralogical matrix of loess contains quartz, phyllosilicates and mixed layer clays, while its geochemical composition contains high amounts of detrital Fe-Ti oxides and aeolian transported Al and Zr. Based on the multi-proxy approach applied here, the loess profile is partitioned in three layers. Holocene average deposition rates (~2.5 cm/ka) broadly agree with modern Sahara dust deposition (~2.0 cm/ka) and long-term postglacial Mediterranean mountain denudation rates (~0.5 cm/ka). Such low rates provided ample time for post depositional modifications, such as decalcification, deferrification and removal of K, evident from the trends of chemical weathering proxies Ca/Sr, Fe/Ti and K/Rb, respectively.

Media companies worldwide are trying to adapt to the new challenges brought about by the economic crisis and technological revolution. However, some of these efforts are doomed to fail because media tends to concentrate on adapting particular elements of their business models, instead of changing the entire business model logic. This work proposes an innovative business model typology and is based on the hypothesis that if a company could re-arrange its structural elements around this typology, it could have much better chances in its fight to overcome the challenges posed by the ever changing and competitive digital ecosystem. To test this typology the authors used case study methodology and drew from evidence collected from in-depth interviews with journalists from two Greek websites. Ultimately, the article provides the basis for generating new theories about business models and finds that even in times of crisis and transformational change, media companies can survive as long as they perceive crisis -and any other kind of challenge for that matter- as an opportunity for creative change.

This study focuses on the way(s) that the economic and the pandemic crisis were covered by media outlets and aims to research whether journalists’ own feelings and experiences of covering both these traumatic events were depicted in their news articles. Drawing on Semetko and Valkenburg’s (2000) set of five generic frames this study focuses on Greece, a country that has been severely hit by both these crises and brings together theories about journalism as emotional labour that defy the prevailing notion of the distant and neutral observers. Moving one step further, this study argues that journalists convey their source’s emotions, but in some cases, they also reveal their own feelings through their news articles. Findings suggest that apart from the already documented frames, (i.e., attribution of responsibility, conflict, human interest, economic consequences, and morality), journalists used the trauma frame, a notion we use to refer to news articles that essentially reflect and reveal journalists’ own emotions. This finding refutes the traditional understanding of quality journalistic discourse as one stripped of emotional expression and opens new pathways for research.

Corundum primary deposits in Greece occur in four locations: Paranesti in Drama and Gorgona in Xanthi, both belonging to the wider Rhodope Massif, as well as, Ikaria island and Kinidaros in Naxos island, both belonging to Attic-Cycladic Massif. Eight samples were examined with spectroscopic methods (FTIR, UV-Vis, EDXRF) in order to better characterize these four primary deposits: two pink sapphires from Paranesti, a pink and a blue sapphire from Gorgona, two blue sapphires from Ikaria and three blue sapphires from Kinidaros. Under the microscope, all samples present characteristics linked to post-crystallization deformation, decreasing their gem quality. The FTIR absorption spectra of all samples present in different relative intensities, bands of boehmite, diaspore, goethite, mica and/or chlorite inclusions and CO2 in fluid inclusions. Boehmite and diaspore inclusions are most likely epigenetic. In the UV-Vis spectra, the pink color of the samples is linked with Cr3+ absorptions and the blue color with absorptions due to Fe2+-Ti4+ intervalence charge transfer. EDXRF analyses in the studied samples show relatively high titanium and iron concentrations that are related with mineral inclusions. Gallium is slightly variable in samples from different regions, also, different colored samples from Gorgona present diverse gallium content.

The Vathi porphyry Cu-Au±Mo deposit is located in the Kilkis ore district, northern Greece. Hydrothermally altered and mineralized samples of latite and quartz monzonite are enriched with numerous rare and critical metals. The present study focuses on the bulk geochemistry and the mineral chemistry of pyrite, chalcopyrite, magnetite, and titanite. Pyrite and chalcopyrite are the most abundant ore minerals at Vathi and are related to potassic, propylitic, and sericitic hydrothermal alterations (A- and D-veins), as well as to the late-stage epithermal overprint (E-veins). Magnetite and titanite are found mainly in M-type veins and as disseminations in the potassic-calcic alteration of quartz monzonite. Disseminated magnetite is also present in the potassic alteration in latite, which is overprinted by sericitic alteration. Scanning electron microscopy and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses of pyrite and chalcopyrite reveal the presence of pyrrhotite, galena, and Bi-telluride inclusions in pyrite and enrichments of Ag, Co, Sb, Se, and Ti. Chalcopyrite hosts bornite, sphalerite, galena, and Bi-sulfosalt inclusions and is enriched with Ag, In, and Ti. Inclusions of wittichenite, tetradymite, and cuprobismutite reflect enrichments of Te and Bi in the mineralizing fluids. Native gold is related to A- and D-type veins and is found as nano-inclusions in pyrite. Titanite inclusions characterize magnetite, whereas titanite is a major host of Ce, Gd, La, Nd, Sm, Th, and W.

Pyrolysis is an environmentally friendly method, which is often used for the recycling of the plastics included in waste electric and electronic equipment (WEEE); since secondary valuable materials can be produced. Brominated flame retardants (BFRs) are usually added into these plastics to reduce their flammability; but they are toxic substances. The aim of this work is to examine the thermal behaviour and the products obtained after pyrolysis of polymer blends that consist of acrylonitrile-butadiene-styrene (ABS), high-impact polystyrene (HIPS), polycarbonate (PC) and polypropylene (PP) with composition that simulates real WEEE; in the absence and presence of a common BFR, tetrabromobisphenol A (TBBPA), in order to investigate its effect on pyrolysis products. Blends were prepared via the solvent casting method and the melt-mixing in an extruder; it was revealed that the latter method may be a better choice for blends preparation, since it didn’t affect the products obtained. The chemical structure of each polymeric blend was identified by Fourier Transform Infrared spectroscopy (FTIR). Thermal degradation of the blends was evaluated by thermogravimetric (TG) experiments performed using a thermal analyser (TGA) and a pyrolyser for evolved gas analysis (EGA). It was observed that blends had a similar behaviour during their thermal degradation; and in most cases, they followed a one-step mechanism. Pyrolysis products were identified by the pyrolyser combined with a Gas Chromatographer/Mass Spectrometer (GC/MS); and comprised various useful compounds, such as monomers, aromatic hydrocarbons, phenolic compounds, etc. that could be used as chemical feedstock. Furthermore, it was found that TBBPA affected products’ distribution by enhancing the formation of phenolic compounds and on the other hand by resulting in brominated compounds, such as dibromophenol.

The lithologies and structural features of the exposed rocks of the Serbo-Macedonian massif in the Vertiskos and Kerdilion Mts. have been studied in detail by carrying out km-long cross-sections. Moreover, a new tectonostratigraphic architecture for the massif is proposed, based on the migmatization and anatexis that the rocks pertain, under which the specific exposed rocks have been placed into the Vertiskos and Kerdilion Units. The latter approach differs from the traditional view, which is based solely on the lithological difference between the units. In particular, in the Vertiskos Mt., mica schists, garnet-bearing two-mica gneisses, and predominantly two-mica gneisses, without a sign of anatexis and migmatization, overlie tectonically, biotite gneisses and layered amphibolite gneisses into which migmatization and anatexis takes place. The former constitute the Vertiskos Unit, whereas the latter have been grouped into the Kerdilion Unit, since they are of similar lithologies and affinities with rocks of the Kerdilion Unit. The Kerdilion Mt. is a large antiform made up of biotite gneisses alternating with marbles, which are similarly characterized by intense migmatization and anatexis. These rocks are intruded by the Oreskia granite, which is foliated and follows the general trend of the country rocks. All the rocks are folded with isoclinal to tight folds, and the contact between the two units is a mylonitic shear zone with a top-to-the-SW sense-of-shear. Also, a large volume of ultramafic rocks occurs between the Vertiskos and Kerdilion Mts., including metamorphosed rocks like metagabbros to massive amphibolites, which is assigned to the Therma-Volvi-Gomati Complex (TVGC). These rocks have been found in tectonic contact, i.e., shear zones with top-to-the-SW sense-of-shear, only with the rocks of the Kerdilion Unit. Taking into account our new tectonostratigraphic architecture, the contact between the Vertiskos and Kerdilion Units is not located along the western side of the marbles, as the latter are exposed in the Kerdilion Mt. It is traced westerly in the Vertiskos Mt. dipping with intermediate angles towards the SW, due to NW-trending, map-scale, isoclinal folding. The ultramafic rocks of the TVGC are in tectonic contact with the rocks of the Kerdilion Unit, but not the two-mica gneisses of the Vertiskos Unit, and the Arnea granite intrudes not only the Vertiskos Unit as previously considered, but the rocks of the Kerdilion Unit, as well.

The chapter offers a theoretical overview and understanding on issues regarding the way technological disruption transforms old habits and practices in newsrooms leading to innovative storytelling that transcends time and space. The emergence of social media as a main news source, the extensive use of mobile platforms and the advent of complex technologies such as virtual reality (VR) and artificial intelligence (AI) are paving the way for new forms of journalism that are shaping the future of the industry. In this context, this chapter defines and adequately describes the term digital media while, at the same time it sheds light on new forms of journalism that arise from the vast outspread of ‘smart technology' such as conversational journalism, data journalism, drone journalism, network journalism, robot journalism, selfie journalism, slow journalism, and virtual reality journalism.

Introduction: The aim of the present study was to investigate how different aging protocols can affect the flexural strength and phase transformations of yttrium-stabilized zirconia ceramics (Y-TZP) for monolithic restorations. Materials and methods: Bar-shaped specimens from two zirconia ceramics bars were divided into three groups: a. no treatment (c), b. aging in an autoclave (a), and c. thermal cycling (t). The flexural strength was determined by the 3-point bending test and statistical analysis was performed to determine significant differences ( p< 0.05). Weibull statistics was used to analyze the dispersion of strength values while surface microstructural analysis was performed through X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Results: Aging did not significantly affect the flexural strength but differences were recorded between the two groups, with group A presenting higher strength values and m-phase percentages. Conclusions: The observed differences between the two ceramics could be attributed to variations in composition and processing.

This chapter assesses the trauma that media professionals experience as eye-witnesses of the disturbing and intense events associated with their everyday working routine. In particular, this chapter examines recent profession-based reports on journalistic trauma to explore affective labour in media ecosystems of crisis-ridden countries and the impact of covering traumatic events on media professionals. Based on qualitative research, this chapter aims to reconceptualise journalism as a primarily affective profession in the crisis-ridden countries of SE Europe.