Dwarf elephants, pygmy hippos and various species of micromammals are some of the animals that lived on the island of Cyprus, 11,000 to 13,000 years ago. Fossil skeletal material of the pygmy hippopotamus Phanourios minor has been excavated from various fossiliferous sites in Cyprus, including Aghia Napa. Phanourios minor is considered to be the smallest of all known insular hippopotamuses. The animal is estimated to have measured about 76 cm (2.5 ft) tall and 121 cm (4.0 ft) long. During our study, material from Aghia Napa was used in order to attempt to reconstruct the palaeoclimatic conditions at the time this species lived on the island. The method used to determine the living conditions of this extinct species is the isotopic analysis of the bioapatite of bone and tooth samples. According to our results, and in comparison, to data from other similar studies, the average temperature in Cyprus was probably lower than 24 degrees C and in general the palaeoclimate (based on temperature) in Aghia Napa, Cyprus 12,000 years ago, was not very different to what it is currently, even though the age of the site coincides with the Younger dryas cold event. This has also been reported by other isotopic studies from Greece and the SE Mediterranean region for the specific era, according to which a cold climate is indicated, slowly passing on to a warmer period. According to today's data, we are now experiencing a warm period. The question that remains is how and to which extent, the SE Mediterranean region was actually affected by the cold event.

In this work we examine the hydrochemical and isotopic characteristics of the thermal fluids in the Aristino geothermal area in the southwestern margin of the Loutros-Feres-Soufli Tertiary basin (LFS), which is located west of Evros river in Northeastern Greece, in order to identify their possible origin and the expected procedures responsible for the alteration of the initial composition of them. The studied fluids are characterized by high Cl¯ and Br¯ contents, which indicate a higher or lower marine contribution. Furthermore, the elevated B and Li+ values and the low Mg2+ values respectively, are related to high temperatures indicative of water-rock interaction procedures. Additionally, we observe an enrichment of δ18O values, which is another indicator of water-rock interaction that occurs in areas with high thermal potential. Finally, we attempt to evaluate the deep reservoir temperatures with the application geothermometers. Their values reflect an equilibrium process with the probable existence of a deep hydrothermal system of middle to high enthalpy.

In this work we study the isotopic and hydrochemical properties of waters emerging from Nestos river delta basin (Erasmio, Eratio and Myrodato), which is forming the continental margin of the broader graben type basin of Prinos that includes the Nestos delta and the offshore extension between Thassos island and the main land around Kavala bay. Our scope is the identification of the procedures that are related to the waters composition as well as their origin. Some of our samples are characterized by low Cl¯ which excludes the marine contribution while the others present high Cl¯ and Br¯ which indicated marine participation. In addition, the low values of B and Li+ show that these elements derive from seawater, which is more or less diluted by fresh water with no water-rock interaction. This assumption is, also, confirmed by the δ18O and δ34S isotopic values. Finally, we use isotopic geothermometers for the evaluation of reservoir temperature and we conclude to the existence deep geothermal field of low to middle enthalpy, with the exception of one sample which has middle to high enthalpy.

Objectives: Isotopic analysis has been proven a valuable tool for reconstructing dietary habits in the ancient world. In this work we examine the evolution of Greek diet from the Neolithic period (6800-3000 BC) to modern times. Materials and Methods: We present isotopic analysis results for delta C-13 and delta N-15 of adult human bone collagen from ancient (Kaiadas in Sparta) and modern populations (Crete), while at the same time we review published results for delta C-13 and delta N-15 of adult human bone collagen from Neolithic to modern times of Greece. Results: The delta C-13 isotopic values evolve to more positive values, while they present a greater variability toward modern times. Furthermore, the delta N-15 values gradually increase over time. Discussion: We discuss the differences i) in human diet through time for the whole Greece and ii) individually for the island of Crete and we conclude that over time human diet becomes richer in high trophic level proteins such as marine sources with a larger variety of food sources.

During antiquity, it is known that glass was produced in specialized primary workshops in Levant and Egypt, and this glass was melted and formed into objects in secondary workshops, and distributed in most cities and towns of the Roman Empire. Great efforts, although it is difficult, have been made to distinguish where it was produced. In this study, we perform chemical analysis on 48 glass samples (22 moils and 26 glass artefacts) dated to the 6th century CE from Vasileos Irakleiou Street, 45, Thessaloniki in northern Greece by using Scanning Electron Microscopy (SEM) with Energy–Dispersive X-ray microanalysis (EDX). All glasses were produced with natron as a flux and based on the sodium oxide content we divided them into two groups. Most of the glasses’ chemical analysis indicates that they originated from Egypt, and can be categorized as HIMT and others as Roman Mn or Roman Mn-Sb. MnO is the main decolorizer, while in some samples MnO coexists with Sb2O3. Finally, recycling processes are evident in most of the samples.

In this article we present an isotopic analysis of human bone collagen (δ13Ccol, and δ15Ncol) and bone apatite (δ13C) for diet reconstruction, as well as δ18Oap of human bone apatite for climate reconstruction, using samples from Northern Greece. Radiocarbon dating analysis was conducted on three of the Agras samples and the results (from 1000 to 800 BC) correspond to the Early Iron Age. Isotopic values for δ13Ccol range from −20.5‰ to −16‰ and for δ15Ncol from 6‰ to 11.1‰—a strong indication of a C3-based diet, with contributions by C4 and freshwater fish elements. The results were compared to the ones from Roman Edessa, and Alexandreia (a contemporary city near Edessa), as well as to other Early Iron sites in Greece and wider Europe. In general, the results from Agras are in good agreement with the results from Northern Greece, with the exception of the Makriyalos site, and are quite close to those of Croatia’s and Hungary’s sites. Additionally, from the δ18Oap results we calculated the oxygen isotopic composition of consumed water for Agras (from −9.6‰ to −10.9‰) and for Roman Edessa (from −9.6‰ to −11.2‰) for the palaeoclimate and palaeomobility reconstruction.

In this study we present the isotopic signatures of quarries located in North-East (Tempi, Tisaion, Pangaio), Southern (Hymittos, Penteli) Greece in order to enrich the existing databases used in ancient marble provenance. This expansion of the databases will enhance our understanding in the archaeological characterization of ancient monuments and potentially determine economic and cultural associations and trade routes. Furthermore, it will reduce the overlap of the isotopic signals of marbles in the up to now databases, enhancing the dissemination and facilitate the provenance studies of the ancient marble monuments .

Hydrochemical and isotopic characteristics of fluids from major geothermal fields of middle/low temperature in N/NE Greece are examined [basins: Strymon River (SR), Nestos River Delta (ND), Xanthi–Komotini (XK), Loutros–Feres–Soufli (LFS) and Rhodope Massif]. The geodynamic context is reflected to isotopic/chemical composition of fluids, heat flow values and elevated CO 2 concentrations in emitted fluids. B and Li are derived from leaching of the geothermal systems hosting rocks. δ 18 O H2O , δ 18 O SO4 , δ 13 C CO2 values and chemical compositions of Cl, B and Li of geothermal discharges suggest two distinct source fluids. Fluids in SR exhibit high B/Cl and Li/Cl ratios, suggesting these constituents are derived from associated magmas of intermediate composition (andesitic rocks). Geothermal discharges in LFS exhibit low B/Cl and Li/Cl ratios, implying acid (rhyolitic) magmatism. δ 13 C CO2 and CO 2 /(CO 2 + 10 5 He) ratios in the west part, suggest fluids affected by addition of volatiles released from subducted marine sediments. For the eastern systems, these ratios suggest gas encountered in systems issued from mixing of crustal and mantle-derived volatiles. Isotopic geothermometers reflect, for the same direction, equilibrium processes more ( LFS , XK ) or less (SR) pronounced and discriminate the geothermal field from low to middle [SR, ND (Erasmio)] and middle to high enthalpy [ND (Eratino), LFS, XK].

Salts crystallizing in the pore space of building stones cause stone monument degradation. The origin of these salts can be variable: marine, air pollution, together with marine aerosols, building or restoration material. Previous studies using sulfur and nitrogen isotopes demonstrated the important role of atmospheric sulfur and nitrogen to black crust formation and determining it as a principal component of salt weathering of stone monuments. In this study we present isotopic measurements of black crusts from monuments located in North Greece and Attica. The applied methodology is capable to distinguish the sources of the sulfate salts (atmospheric pollution, marine aerosols, bio-pollution).

In recent years, isotopic analysis has been proven a valuable tool for the determination of the origin of various materials. In this article, we studied the 18O and 13C isotopic values of 210 olive oil samples that were originated from different regions in Greece in order to verify how these values are affected by the climate regime. We observed that the δ18O isotopic values range from 19.2 ‰ to 25.2 ‰ and the δ13C values range from −32.7 ‰ to −28.3 ‰. These differences between the olive oils’ isotopic values depended on the regional temperature, the meteoric water, and the distance from the sea. Furthermore, we studied the 13C isotopic values of biophenolic extracts, and we observed that they have same capability to differentiate the geographic origin. Finally, we compared the isotopic values of Greek olive oils with samples from Italy, and we concluded that there is a great dependence of oxygen isotopes on the climatic characteristics of the different geographical areas.

This corrects the article DOI: 10.1103/PhysRevE.94.062403.

It was realized from the early days of Chemical Physics (Rev. Mod. Phys. 35, 496 (1963)) that the energy E_HF of the Slater determinant (SlDet) |Φ _HF⟩, obtained by the single particle Hartree-Fock (HF) equation, does not coincide with the minimum energy of the functional ⟨Φ|H|Φ⟩ where |Φ⟩ is a SlDet and H is the many particle Hamiltonian. However, in most textbooks, there is no mention of this fact. In this paper, starting from a Slater determinant |Φ⟩ with its spin orbitals calculated by the standard HF equation or other approximation, we search for the maximum of the functional |⟨Φ ^'|H|Φ⟩|, where |Φ ^'⟩ is a SlDet and H is the exact Hamiltonian of an atom or a molecule. The element |⟨Φ _1|H|Φ⟩| with |Φ _1⟩ the maximizing |Φ ^'⟩ gives a value larger than ⟨Φ|H|Φ⟩. The next step is to calculate the corresponding maximum overlap ⟨Φ_2|H|Φ _1⟩| and subsequently |⟨Φ _n+1|H|Φ _n⟩| until |⟨Φ _m+1|H|Φ _m⟩ -⟨Φ _m-1|H|Φ _m⟩|≤ε, where ε determines the required numerical accuracy. We show that the sequence a_n=|⟨Φ _n+1|H|Φ_n⟩| is ascending and converges. We applied this procedure for determining the eigenstate energies of several configurations of H_3, the Lithium atom, LiH and Be. After comparing our values with those of the configuration interaction we found that our deviations are in the range 10^-5to 10^-8 and the ground state energy is significantly below that of the standard HF calculations.

Recent years have witnessed tremendous research in quantum dots as excellent models of quantum physics at the nanoscale and as excellent candidates for various applications based on their optoelectronic properties. This review intends to present theoretical and experimental investigations of the near-field optical properties of these structures, and their multimodal applications such as biosensors, biological labels, optical fibers, switches and sensors, visual displays, photovoltaic devices and related patents.

We employ Real-Time Time-Dependent Density Functional Theory to study hole oscillations within a B-DNA monomer (one base pair) or dimer (two base pairs). Placing the hole initially at any of the bases which make up a base pair, results in THz oscillations, albeit of negligible amplitude. Placing the hole initially at any of the base pairs which make up a dimer is more interesting: For dimers made of identical monomers, we predict oscillations with frequencies in the range f approximate to 20-40 THz, with a maximum transfer percentage close to 1. For dimers made of different monomers, f approximate to 80-400 THz, but with very small or small maximum transfer percentage. We compare our results with those obtained recently via our Tight-Binding approaches and find that they are in good agreement.

We employ two tight-binding (TB) approaches to systematically study the electronic structure and hole or electron transfer in B-DNA monomer polymers and dimer polymers made up of N monomers (base pairs): (I) at the base-pair level, using the onsite energies of base pairs and the hopping integrals between successive base pairs, i.e., a wire model and (II) at the single-base level, using the onsite energies of the bases and the hopping integrals between neighboring bases, i.e., an extended ladder model since we also include diagonal hoppings. We solve a system of M (matrix dimension) coupled equations [(I) M=N, (II) M=2N] for the time-independent problem, and a system of M coupled first order differential equations for the time-dependent problem. We perform a comparative study of stationary and time-dependent aspects of the two TB variants, using realistic sets of parameters. The studied properties include HOMO and LUMO eigenspectra, occupation probabilities, density of states and HOMO-LUMO gaps as well as mean over time probabilities to find the carrier at each site [(I) base pair or (II) base], Fourier spectra, which reflect the frequency content of charge transfer, and pure mean transfer rates from a certain site to another. The two TB approaches give coherent, complementary aspects of electronic properties and charge transfer in B-DNA monomer polymers and dimer polymers.

We call monomer a B-DNA base pair and study, analytically and numerically, electron or hole oscillations in monomers, dimers and trimers. We employ two tight binding (TB) approaches: (I) at the base-pair level, using the on-site energies of the base pairs and the hopping parameters between successive base pairs i.e. a wire model, and (II) at the single-base level, using the on-site energies of the bases and the hopping parameters between neighbouring bases, specifically between (a) two successive bases in the same strand, (b) complementary bases that define a base pair, and (c) diagonally located bases of successive base pairs, i.e. an extended ladder model since it also includes the diagonal hoppings (c). For monomers, with TB II, we predict periodic carrier oscillations with frequency [Formula: see text]-550 THz. For dimers, with TB I, we predict periodic carrier oscillations with [Formula: see text]-100 THz. For trimers made of identical monomers, with TB I, we predict periodic carrier oscillations with [Formula: see text]-33 THz. In other cases, either with TB I or TB II, the oscillations may be not strictly periodic, but Fourier analysis shows similar frequency content. For dimers and trimers, TB I and TB II are successfully compared giving complementary aspects of the oscillations.

We calculate the lowest ionisation and excitation energies in a variety of biologically important molecules, i.e. pi-conjugated systems like DNA and RNA bases and isomers plus related heterocyclic molecules. For approximately half of these molecules, there are no experimental and theoretical/numerical data in the literature, as far as we know. These electronic transitions are mainly but not exclusively of pi and pi-pi* character, respectively. We perform symmetry-constrained density functional theory (DFT) geometry optimisation at the B3LYP/6-311++G** level of theory. At the DFT-obtained ground-state geometries, we calculate vertical ionisation energies with ionisation potential coupled cluster with singles and doubles (IP-EOMCCSD) and vertical excitation energies with the completely renormalised equation of motion coupled cluster with singles, doubles, and non-iterative triples (CR-EOMCCSD(T)) method. We also investigate whether a simple semi-empirical Huckel-type model approach with novel parametrisation could provide reasonable estimates of the lowest pi ionisation and pi-pi* excitation energies. Our coupled cluster (CC) results are in very good agreement with experimental data, while the Huckel-type model predictions generally follow the trends with some deviation. Finally, we investigate the effect of basis set in IP-EOMCCSD energies and we compare our CR-EOMCCSD(T) results with time-dependent DFT (TDDFT) ones.