Θαλάσσιος χωροταξικός σχεδιασμός για την υπεράκτια αιολική ενέργεια: εφαρμογή στην περιφέρεια βορείου αιγαίου

Εθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) “Περιβάλλον και Ανάπτυξη

Effects of Mutations on the Molecular Dynamics of Oxygen Escape from the Dimeric Hemoglobin of Scapharca inaequivalvis

Like many hemoglobins, the structure of the dimeric hemoglobin from the clam Scapharca inaequivalvis is a “closed bottle” since there is no direct tunnel from the oxygen binding site on the heme to the solvent. The proximal histidine faces the dimer interface, which consists of the E and F helicies. This is significantly different from tetrameric vertebrate hemoglobins and brings the heme groups near the subunit interface. The subunit interface is also characterized by an immobile, hydrogen-bonded network of water molecules. Although there is data which is consistent with the histidine gate pathway for ligand escape, these aspects of the structure would seem to make that pathway less likely. Locally enhanced sampling molecular dynamics are used here to suggest alternative pathways in the wild-type and six mutant proteins. In most cases the point mutations change the selection of exit routes observed in the simulations. Exit via the histidine gate is rarely seem although oxygen molecules do occasionally cross over the interface from one subunit to the other. The results suggest that changes in flexibility and, in some cases, creation of new cavities can explain the effects of the mutations on ligand exit paths

New integrable models and analytical solutions in f(R) cosmology with an ideal gas

In the context of f(R)-gravity with a spatially flat FLRW metric containing an ideal fluid, we use the method of invariant transformations to specify families of models which are integrable. We find three families of f(R) theories for which new analytical solutions are given and closed-form solutions are provided.S. B. acknowledges support by the Research Center for Astronomy of the Academy of Athens in the context of the program “Testing general relativity on cosmological scales” (Ref. number 200/872). A. P. was financially supported by FONDECYT Grants No. 3160121. A. P. thanks the University of Athens for the hospitality provided while part of this work was performed. J. D. B. acknowledges support from the Science and Technology Facilities Council (STFC) of the United Kingdom

Complexation of Lysozyme with Adsorbed PtBS-b-SCPI Block Polyelectrolyte Micelles on Silver Surface

We present a study of the interaction of the positively charged model protein lysozyme with the negatively charged amphiphilic diblock polyelectrolyte micelles of poly(tert-butylstyrene)-bsodium (sulfamate/carboxylate)isoprene) (PtBS-b-SCPI) on the surface of silver. The adsorption kinetics are monitored by surface plasmon resonance and the surface morphology by atomic force microscopy. The micellar adsorption kinetics is dictated by two processes and the micellar layer morphology shows that the micelles do not lose their integrity upon adsorption. The complexation of lysozyme with the adsorbed micellar layers depends on the micelles arrangement and density in the underlying layer and lysozyme follows the local morphology of the underlying roughness. When the micellar adsorbed amount is small, the layers show low capacity in protein binding and low resistance in loading. When the micellar adsorbed amount is high the situation is inversed. The adsorbed layers both with or without added protein are found to be irreversibly adsorbed on the Ag surface

Archaeology in the community - educational aspects: Greece: a case-study

Heritage education in Greece reproduces and reassures the individual, social and national self. My purpose is to discuss the reasons for this situation and, by giving account of the recent developments in Western Europe and the new Greek initiatives, to improve the study of the past using non-traditional school education. In particular. Local History projects through the Environmental Education optional lessons allow students to approach the past in a more natural way, that is through the study of the sources and first hand material. The community itself is involved in the projects either as a geographical place where the children's activities are located and referred to or as a source of a different perspective which enhances the school's world view. Museum projects are not everywhere equally profitable in Greece, especially where they are not combined with other activities in general school planning. Being a teacher in a Greek school I started to set up similar projects within Environmental Education, in order to articulate a syllabus which might work as a model for my colleagues all over Greece. My project put emphasis - as New History did - on the ability of (and the necessity for) children to undertake small-scale academic research including Archaeology. It emphasised also the interaction between the community and schools, and the advance of long-term education for sustainable development. My involvement in the educational affair stimulated official and/or unofficial improvements which fit well with cross-developments announced in the Greek educational system as part of a very recent tendency in the socio-political sphere to alter the current situation. Children as not only long-term, but also short-term mediators of knowledge and attitudes constitute a major factor for change within the community

Synthesis and solution properties of a temperature-responsive PNIPAM–b-PDMS–b-PNIPAM triblock copolymer

In this paper, we report the synthesis and self-assembly of a novel thermoresponsive PNIPAM60–b-PDMS70–b-PNIPAM60 triblock copolymer in aqueous solution. The copolymer used a commercially available precursor modified with an atom transfer radical polymerization (ATRP) initiator to produce an ABA triblock copolymer via ATRP. Small-angle neutron scattering (SANS) was used to shed light on the structures of nanoparticles formed in aqueous solutions of this copolymer at two temperatures, 25 and 40 °C. The poly(dimethylsiloxane) block is very hydrophobic and poly(N-isopropylacrylamide) (PNIPAM) is thermoresponsive. SANS data at 25 °C indicates that the solutions of PNIPAM–b-PDMS–b-PNIPAM copolymers form well-defined aggregates with presumably core–shell structures below cloud point temperature. The scattering curves originating from nanoparticles formed at 40 °C in 100% D2O or 100% H2O were successfully fitted with the Beaucage model describing aggregates with hierarchical structure