Καθορισμός διαδικασιών εκπόνησης σχεδίου εκκένωσης σε υπόγειο χώρο με εξέταση ιδιαιτέρων χαρακτηριστικών.Παράδειγμα εφαρμογής σον υπόγειο χώρο του Τεχνολογικού Πάρκου Λαυρίου

94 σ.Εθνικό Μετσόβιο Πολυτεχνείο -- Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) "Σχεδιασμός & Κατασκευή Υπόγειων Έργων"Η παρούσα εργασία σκοπό έχει την παροχή οδηγιών για την κατάστρωση μιας μελέτης εκκένωσης σε περίπτωση εκτάκτου ανάγκης σε υπόγειο χώρο. Γίνεται χρήση στοιχείων προερχόμενα από έρευνες , κανονισμούς παθητικής πυροπροστασίας (ελληνικούς και ξένους) με σκοπό την εξαγωγή εκτιμήσεων για προσδιορισμό χρόνων που αφορούν το τμήμα της εκκένωσης το οποίο επηρεάζεται από ανθρώπινη συμπεριφορά και εξαρτάται από τα διατιθέμενα μέσα και εγκαταστάσεις του υπογείου χώρου. Για τον υπολογισμό του χρόνου που αφορά το τμήμα εκκένωσης που συνδέεται με κίνηση ανθρώπων γίνεται μία προσέγγιση κυκλοφοριακής ροής ανθρώπων συνδυασμένη με ανθρωπομετρικά δεδομένα ,από όπου εξάγονται οι βασικές σχέσεις εκτιμήσεων μεγεθών παροχής και χρόνου. Αυτή η αναλυτική προσέγγιση συγκρίνεται με την προσομοίωση υπολογιστών και γίνεται μία κατηγοριοποίηση των διατιθέμενων προγραμμάτων. Όλες οι οδηγίες και κανόνες που παρουσιάζονται , βρίσκουν εφαρμογή σε ένα παράδειγμα , στον υπόγειο χώρο του τεχνολογικού πάρκου Λαυρίου, όπου η ανάλυση καταλήγει στην σύνταξη του σχεδίου εκκένωσης αποτελούμενο από σχέδια και τεχνική έκθεση οδηγιών.The purpose of this paper is to give the necessary guidelines to complete an evacuation plan in case of emergency in an underground space. The data within this paper have been taken from research studies , standards for fire protection engineering (greek and foreighners) in order to extract estimates about the times concernig the section of evacuation refering to human behaviour and depends from installations in the underground space. To establish a pattern of computation time concerning the section of evacuation, refering to human movement an approach is used with similar elements from vehicle traffic flow. This combined with anthropometrical data leads to the basic relations between time and quantity of people per second through an emergency door exit. This analytical approach is compared with results from computer simulation among with a classifiacation of available software. All these instructions and guidelines are apllicable in an example of the underground space located in Technological Park of Lavrio, where the whole analysis has the result to produce an evacuation plan made from templates and technical reports.Φίλιππος Α. Κυρίτση

Water and protein dynamics in protein-water mixtures over wide range of composition

© 2012 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] Water and protein dynamics in two globular protein-water systems, water-lysozyme and water-BSA (bovine serum albumine), were studied by differential scanning calorimetry (DSC), dielectric relaxation spectroscopy (DRS) and thermally stimulated depolarization currents (TSDC) techniques. Water equilibrium sorption isotherms (ESI) measurements were also recorded at room temperature. The samples covered a wide range of composition, from practically dry solid pellets (2wt% of water) to dilute solutions (82wt% of water). Crystallization and melting events of water were studied by DSC and the amount of uncrystallized water was calculated. The evolution of dynamics with hydration level was followed for various dielectric relaxation processes, the emphasis being given to relaxation processes of polar groups on the surface of the proteins and of uncrystallized water molecules. A relationship between the formation of a conductive percolating water cluster and the saturation of the water process was found.This research has been co-financed by the European Union (European Social Fund - ESF) and Greek national funds through the Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) - Research Funding Program: Heracleitus II. Investing in knowledge society through the European Social Fund.Kyritsis, A.; Panagopoulou, A.; Pissis, P.; Sabater I Serra, R.; Gómez Ribelles, JL.; Shinyashiki, N. (2012). Water and protein dynamics in protein-water mixtures over wide range of composition. IEEE Transactions on Dielectrics and Electrical Insulation. 19(4):1239-1246. https://doi.org/10.1109/TDEI.2012.6259997S1239124619

Chitosan-Silica Hybrid Porous Membranes

Chitosan–silica porous hybrids were prepared by a novel strategy in order to improve the mechanical properties of chitosan (CHT) in the hydrogel state. The inorganic silica phase was introduced by sol–gel reactions in acidic medium inside the pores of already prepared porous scaffolds. In order to make the scaffolds insoluble in acidic media chitosan was cross-linked by genipin (GEN) with an optimum GEN concentration of 3.2 wt.%. Sol–gel reactions took place with Tetraethylorthosilicate (TEOS) and 3-glycidoxypropyltrimethoxysilane (GPTMS) acting as silica precursors. GPTMS served also as a coupling agent between the free amino groups of chitosan and the silica network. The morphology study of the composite revealed that the silica phase appears as a layer covering the chitosan membrane pore walls. The mechanical properties of the hybrids were characterized by means of compressive stress–strain measurements. By immersion in water the hybrids exhibit an increase in elastic modulus up to two orders of magnitude.The research project is implemented within the framework of the Action "Supporting Postdoctoral Researchers" of the Operational Program "Education and Lifelong Learning" (Action's Beneficiary: General Secretariat for Research and Technology), and is co-financed by the European Social Fund (ESF) and the Greek State, Grant Number: NARGEL-PE5(2551). JFM thanks the Portuguese Foundation for Science and Technology (FCT) for financial support through the PTDC/FIS/115048/2009 project. JLGR acknowledges the support of the Ministerio de Economia y Competitividad, MINECO, through the MAT2013-46467-C4-1-R project

Structurally Diverse Metal Coordination Compounds, Bearing Imidodiphosphinate and Diphosphinoamine Ligands, as Potential Inhibitors of the Platelet Activating Factor

Metal complexes bearing dichalcogenated imidodiphosphinate [R2P(E)NP(E)R2′]− ligands (E = O, S, Se, Te), which act as (E,E) chelates, exhibit a remarkable variety of three-dimensional structures. A series of such complexes, namely, square-planar [Cu{(OPPh2)(OPPh2)N-O, O}2], tetrahedral [Zn{(EPPh2)(EPPh2)N-E,E}2], E = O, S, and octahedral [Ga{(OPPh2)(OPPh2)N-O,O}3], were tested as potential inhibitors of either the platelet activating factor (PAF)- or thrombin-induced aggregation in both washed rabbit platelets and rabbit platelet rich plasma. For comparison, square-planar [Ni{(Ph2P)2N-S-CHMePh-P, P}X2], X = Cl, Br, the corresponding metal salts of all complexes and the (OPPh2)(OPPh2)NH ligand were also investigated. Ga(O,O)3 showed the highest anti-PAF activity but did not inhibit the thrombin-related pathway, whereas Zn(S,S)2, with also a significant PAF inhibitory effect, exhibited the highest thrombin-related inhibition. Zn(O,O)2 and Cu(O,O)2 inhibited moderately both PAF and thrombin, being more effective towards PAF. This work shows that the PAF-inhibitory action depends on the structure of the complexes studied, with the bulkier Ga(O,O)3 being the most efficient and selective inhibitor

Synthesis and Study of Fully Biodegradable Composites Based on Poly(butylene succinate) and Biochar

Biodegradable polymers offer a promising alternative to the global plastic problems and especially in the last decade, to the microplastics problems. For the first time, samples of poly(butylene succinate) (PBSu) biocomposites containing 1, 2.5, and 5 wt% biochar (BC) were prepared by in situ polymerization via the two-stage melt polycondensation procedure. BC was used as a filler for the PBSu to improve its mechanical properties, thermal transitions, and biodegradability. The structure of the synthesized polymers was examined by 1H and 13C nuclear magnetic resonance (NMR) and X-Ray diffraction (XRD) along with an estimation of the molecular weights, while differential scanning calorimetry (DSC) and light flash analysis (LFA) were also employed to record the thermal transitions and evaluate the thermal conductivity, respectively. It was found that the amount of BC does not affect the molecular weight of PBSu biocomposites. The fine dispersion of BC, as well as the increase in BC content in the polymeric matrix, significantly improves the tensile and impact strengths. The DSC analysis results showed that BC facilitates the crystallization of PBSu biocomposites. Due to the latter, a mild and systematic increase in thermal diffusivity and conductivity was recorded indicating that BC is a conductive material. The molecular mobility of PBSu, local and segmental, does not change significantly in the biocomposites, whereas the BC seems to cause an increase in the overall dielectric permittivity. Finally, it was found that the enzymatic hydrolysis degradation rate of biocomposites increased with the increasing BC content

Porous polylactic acid-silica hybrids: preparation, characterization, and study of mesenchymal stem cell osteogenic differentiation

A novel approach to reinforce polymer porous membranes is presented. In the prepared hybrid materials, the inorganic phase of silica is synthesized in-situ and inside the pores of aminolyzed polylactic acid (PLA) membranes by sol-gel reactions using tetraethylorthosilicate (TEOS) and glycidoxypropyltrimethoxysilane (GPTMS) as precursors. The hybrid materials present a porous structure with a silica layer covering the walls of the pores while GPTMS serves also as coupling agent between the organic and inorganic phase. The adjustment of silica precursors ratio allows the modulation of the thermomechanical properties. Culture of mesenchymal stem cells on these supports in osteogenic medium shows the expression of characteristic osteoblastic markers and the mineralization of the extracellular matrix.The research project is implemented within the framework of the Action "Supporting Postdoctoral Researchers" of the Operational Program "Education and Lifelong Learning'' (Action's Beneficiary: General Secretariat for Research and Technology), and is co-financed by the European Social Fund (ESF) and the Greek State, Grant No.: NARGEL-PE5(2551). J.R.R. acknowledges funding of his PhD by the Generalitat Valenciana through VALi+d grant (ACIF/2010/238). J.F.M. thanks the Portuguese Foundation for Science and Technology (FCT) for financial support through the PTDC/FIS/115048/2009 project. J.L.G.R. acknowledges the support of the Ministerio de Economia y Competitividad, MINECO, through theMAT2013-46467-C4-1-R project. CIBER-BBN is an initiative funded by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with the assistance from the European Regional Development Fund

Determining the influence of N-acetylation on water sorption in chitosan films

Water absorption in chitosan rapidly increases when the deacetylation degree decreases between 85 and 45%. This seems to contradict the fact that water absorption in chitin is much lower than that of chitosan. The aim of this paper is to understand this feature by measuring the main parameters affecting equilibrium water content. Since swelling capacity depends on the water–polymer interaction, the Flory Huggins interaction parameter was evaluated, finding small or null dependence on the deacetylation degree. Other factor influencing elastic energy is chain stiffness related to the elastic modulus that was measured as a function of deacetylation degree. Besides, crystalline structure was measured by X-ray diffraction patterns as a characteristic of cross-linking density. These observations led us to conclude that the instability of crystals during the swelling process increases with decreasing deacetylation degree, explaining the high equilibrium water content of low deacetylation chitosans.The authors gratefully acknowledge the financial support from the Spanish Ministry of Economy and Competitiveness through the MAT2013-46467-C4-1-R project, including FEDER funds. CIBER-BBN is an initiative funded by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with the assistance of the European Regional Development Fund.Gámiz González, MA.; Piskin, AE.; Pandis, C.; Chatzimanolis-Moustakas, C.; Kyritsis, A.; Marí Soucase, B.; Gómez Ribelles, JL.... (2015). Determining the influence of N-acetylation on water sorption in chitosan films. Carbohydrate Polymers. 133:110-116. https://doi.org/10.1016/j.carbpol.2015.07.02011011613

Local Commutativity and Causality in Interacting PP-wave String Field Theory

In this paper, we extend our previous study of causality and local commutativity of string fields in the pp-wave lightcone string field theory to include interaction. Contrary to the flat space case result of Lowe, Polchinski, Susskind, Thorlacius and Uglum, we found that the pp-wave interaction does not affect the local commutativity condition. Our results show that the pp-wave lightcone string field theory is not continuously connected with the flat space one. We also discuss the relation between the condition of local commutativity and causality. While the two notions are closely related in a point particle theory, their relation is less clear in string theory. We suggest that string local commutativity may be relevant for an operational defintion of causality using strings as probes.Comment: Latex, JHEP3.cls, 18 pages, no figures. v2: add comments about the UV-IR mixing effect displayed in our result. version to appear in JHE