Comparative geomorphological observations in two groups of alluvial fans of Sperchios and Eurotas regions, Greece

Στην παρούσα εργασία μελετήθηκαν συγκριτικά δύο ομάδες αλλουβιακών ριπιδίων του ελληνικού χώρου, η πρώτη στην περιοχή του ποταμού Σπερχειού και η δεύτερη στην περιοχή του ποταμού Ευρώτα. Fia το σκοπό αυτό μετρήθηκαν συγκεκριμένα μορφομετρικά χαρακτηριστικά των λεκανών απορροής των ρεμάτων Τσερλιά, Ξεριά, Γοργοπόταμου, Κερασιά, Ρέτσα και Κάκαρη, καθώς και των ριπιδίων τους, έγινε σύγκριση των μετρήσεων αυτών και βγήκαν συμπεράσματα για το σχηματισμό και την εξέλιξη των ριπιδίων. Παράλληλα έγιναν επιμήκεις τομές της κεντρικής κοίτης των ρεμάτων, πραγματοποιήθηκε κροκαλομετρία εντός της κοίτης των ριπιδίων και αποτυπώθηκαν οι οδοντώσεις των ισοϋψών των ριπιδίων. Κατά την κροκαλομετρία έγινε φανερό ότι το μέσο μέγεθος Μ μειώνεται από την κορυφή προς τη βάση των ριπιδίων. Από τη μελέτη των οδοντώσεων των ισοϋψών προέκυψε ότι τα ριπίδια στην περιοχή του Ευρώτα έχουν υποστεί μεγαλύτερη διάβρωση από αυτά της περιοχής του Σπερχειού. Απ' όλα τα παραπάνω συμπεραίνεται ότι τα μελετούμενα ριπίδια παρουσιάζουν σημαντικές διαφορές τόσο μεταξύ τους (κυρίως για την περιοχή του Σπερχειού) όσο και μεταξύ των δύο περιοχών μελέτης. Αυτό οφε^ται κυρίως στον ρηξιγενή τεκτονισμό, την επικρατούσα λιθολογία και το κλίμα. Οι παράγοντες αυτοί είναι εκείνοι που κυρίως καθορίζουν τη γένεση και εξέλιξη των ριπιδίων και επηρεάζουν το σχήμα, την έκταση και τα επιμέρους χαρακτηριστικά τουςIn the present study two groups of alluvial fans from two different regions in Greece were comparetively studied, the first in the region of Sperchios river and the second in the region ofEurotas river. Distinct morphometric characteristics of the drainage basins of the tributaries Ts er lias, Xerias, Gorgopotamos, Kerasias, Retsas and Kakaris, as well as their fans were measured and compared. Furthermore ,the longitudinal stream profiles were mapped, pebble measurements were made and contour crenulations of the fans were studied. In gravelometry, it was found that the mean size M of the pebbles decreases from the apex to the apron of the fan. The crenulation analysis showed that the fans of the streams ofEurotas region have undergone greater erosion than those of Sperchios region. Remarkable differences exist between the fans of the two regions. These results lead to the conclusion that recent tectonism, the prevailing lithology and climate are responsible for the formation and evolution of the fans and also influence their shape, area and all the other morphometric characteristic

S100A7 and the progression of breast cancer

The S100 gene family comprises more than 20 members whose protein sequences encompass at least one EF-hand Ca(2+ )binding motif. The expression of individual family members is not ubiquitous for all tissues and there appears to be an element of tissue-specific expression. Molecular analysis of breast tumors has revealed that several S100s, including S100A2, S100A4 and S100A7, exhibit altered expression levels during breast tumorigenesis and/or progression. Subsequent studies have started to describe a functional role for these S100 proteins as well as their mechanism of action and the biochemical pathways they modify. The present review outlines what is known about S100A7 in breast cancer and summarizes the need to better understand the importance of this protein in breast cancer

What EU policy framework do we need to sustain High Nature Value (HNV) farming and biodiversity? Policy Paper prepared in the framework of HNV-Link (project funded by the H2020 Research and Innovation Programme under Grant Agreement no 696391)

This policy paper builds upon the work carried out in the framework of HNV-Link (H2020 Project, 2016-2019, www.hnvlink.eu), a thematic multi-actor network on High Nature Value (HNV) Farming involving 13 partners from 10 European countries. The goal of this network is to support HNV farming systems by inspiring and sharing innovations/practices that improve their socio-economic viability while preserving their ecological value and the public services they provide. HNV-Link informs policymakers and authorities at the European and national levels of the main policy stakes around HNV farming, and to recommend adjustments of the Common Agricultural Policy (CAP) and other policies in order to adequately support HNV farming, the territories in which they are embedded, and the communities that depend on them. In Europe, farmers operate within a complex and constraining environment and policy/regulatory framework, including income support and rural development measures of the CAP, but also the numerous regulations related to agriculture, food hygiene/safety, animal health/welfare, environment protection, and climate change. This framework can provide farms with incentives or on the contrary, hinder their development, and it has consequently a major influence on their economic viability and the survival of the communities depending on farming. This institutional framework was designed to deal mainly with the problems that intensive farms face. Far less weight has been placed on designing and implementing policies adapted to the needs of HNV farms, i.e. those low-intensity farms which rely on and safeguard a rich biodiversity and associated ecosystem services made up of a variety of habitats and landscapes elements. Hence, there is a need for a creative yet thoughtful design and implementation of adapted policy measures

Synthesis of calcium aluminates through the polymeric precursor route

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Secondary Bjerknes forces between two bubbles and the phenomenon of acoustic streamers

The translational velocities of two spherical gas bubbles oscillating in water, which is irradiated by a high-intensity acoustic wave field, are calculated. The two bubbles are assumed to be located far enough apart so that shape oscillations can be neglected. Viscous effects are included owing to the small size of the bubbles. An asymptotic solution is obtained that accounts for the viscous drag on each bubble, for large Re based on the radial part of the motion, in a form similar to the leading-order prediction by Levich (1962), C-D = 48/ReT; Re-T --> infinity based on the translational velocity. In this context the translational velocity of each bubble, which is a direct measure of the secondary Bjerknes force between the two bubbles, is evaluated asymptotically and calculated numerically for sound intensities as large as the Blake threshold. Two cases are examined. First, two bubbles of unequal size with radii on the order of 100 pm are subjected to a sound wave with amplitude P-A < 1.0 bar and forcing frequency w(f) =0.51w(10), so that the second harmonic falls within the range defined by the eigenfrequencies of the two bubbles, w(10)<2w(f)<w(20). It is shown that their translational velocity changes sign, becoming repulsive as PA increases from 0.05 to 0.1 bar due to the growing second harmonic, 2w(f), of the forcing frequency. However, as the amplitude of sound further increases, P-A approximate to 0.5 bar, the two bubbles attract each other due to the growth of even higher harmonics that fall outside the range defined by the eigenfrequencies of the two bubbles. Second, the case of much smaller bubbles is examined, radii on the order of 10 mum, driven well below resonance, w(f)/2pi = 20 kHz, at very large sound intensities, P-A approximate to 1 bar. Numerical simulations show that the forces between the two bubbles tend to be attractive, except for a narrow region of bubble size corresponding to a nonlinear resonance related to the Blake threshold. As the distance between them decreases, the region of repulsion is shifted, indicating sign inversion of their mutual force. Extensive numerical simulations indicate the formation of bubble pairs with constant average inter-bubble distance, consisting of bubbles with equilibrium radii determined by the primary and secondary resonance frequencies for small and moderate sound amplitudes or by the Blake threshold for large sound amplitudes. It is conjectured that in experiments where 'acoustic streamers' are observed, which are filamentary structures consisting of bubbles that are aligned and move rapidly in a cavitating fluid at nearly constant distances from each other, bubbles with size determined by the Blake threshold are predominant because those with size determined by linear resonance are larger and therefore become unstable due to shape oscillations