987 resultados para 1-D stacks
Resumo:
Il litorale emiliano romagnolo nell’ultimo secolo risulta sempre più soggetto al fenomeno dell’erosione (Arpae, 2020), incrementata dall’urbanizzazione della costa, dalla riduzione del trasporto solido fluviale e dal fenomeno della subsidenza. Il tratto di costa preso in considerazione nella tesi riguarda l’area di Cesenatico sud: esso non è tra i più critici del litorale regionale, ed è considerato come un settore relativamente stabile dal punto di vita dell’erosione costiera (Arpae, 2020). Ciò è attribuibile in parte alla presenza di barriere frangiflutti lungo tutta l’estensione del paraggio, ma soprattutto a quella del molo sud del Portocanale che intercetta il trasporto solido lungo costa avente verso sud-nord. Per contrastare l’erosione costiera vengono comunque messe in atto a scala locale una serie di “buone pratiche” di gestione del sedimento (linee guida MATTM-Regioni, 2018) come la creazione di un “argine invernale” nel retrospiaggia e lo scraping: una tecnica con la quale, tramite mezzi meccanici, viene rimosso sedimento da accumuli nella spiaggia sommersa ridepositato sulla spiaggia emersa, per aumentarne la superficie in vista dell’avvio della stagione balneare. Il monitoraggio della spiaggia emersa e sommersa è un’attività fondamentale per comprendere gli effetti associati a questi interventi, anche nell’ottica di una gestione sostenibile della costa. Nel 2020 e 2021 sono stati eseguiti a Cesenatico sud una serie di rilievi topografici e batimetrici, all’ultimo dei quali ho personalmente preso parte. I dati sono stati acquisiti con GNSS ed ecoscandaglio single-beam e poi elaborati con software GIS per ottenere mappe di quota/profondità, DTM delle differenze tra rilievi e per ricostruire i profili di spiaggia. Dalle analisi svolte è possibile cogliere i cambiamenti morfologici della spiaggia in seguito alla movimentazione del sedimento in risposta ad attività antropiche e a processi naturali (come significativi eventi di mareggiata).
Resumo:
Dal 2003 ad oggi, le regole di postergazione del rimborso del finanziamento concesso in favore di società a responsabilità limitata e società eterodiretta sono state oggetto di svariate interpretazioni e hanno visto mutare al contempo i propri referenti normativi. Nel presente lavoro, si tenta di portare alla luce l’originaria volontà del legislatore per verificare la possibilità di applicare tali regole a società diverse, tenendo conto delle evoluzioni normative e sociali nel frattempo registratesi all’interno dell’ordinamento.
Resumo:
L’oggetto della tesi di laurea è analizzare l’arte calligrafica dell’artista cinese contemporaneo Fung Ming Chip (Feng Mingqiu 冯明秋, n. 1951). Per poter raggiungere tale obiettivo, è fondamentale, però, esaminare l’intero processo evolutivo della calligrafia cinese, a partire dall’antichità fino a raggiungere l’era moderna, in modo da fornire una panoramica generale delle basi di quest’arte considerata tra le più sublimi della cultura cinese. Nello specifico, si affronta un’analisi di tutti gli aspetti ed elementi caratterizzanti la calligrafia cinese tradizionale; successivamente viene ripercorsa la sua fase di modernizzazione in età contemporanea, che verte sullo sviluppo di due importanti correnti quali la corrente avanguardista e modernista. La calligrafia cinese è stata soggetta a continui mutamenti nel corso della storia e continuano tuttora. Fung Ming Chip è ritenuto tra gli artisti contemporanei più innovativi in campo calligrafico. Le sue abilità, acquisite da autodidatta e apprezzate in tutto il mondo, hanno favorito una produzione artistica alquanto originale. Questo elaborato focalizza l’attenzione in particolare sulle opere che lui realizza sia attraverso l’arte dell’intaglio dei sigilli che attraverso l’arte calligrafica, profondamente legate l’una all’altra. Egli riesce, attraverso la calligrafia, a sviluppare nel pubblico una nuova visione della calligrafia senza sovvertire la calligrafia tradizionale, a cui resta profondamente legato.
Resumo:
Previous earthquakes showed that shear wall damage could lead to catastrophic failures of the reinforced concrete building. The lateral load capacity of shear walls needs to be estimated to minimize associated losses during catastrophic events; hence it is necessary to develop and validate reliable and stable numerical methods able to converge to reasonable estimations with minimum computational effort. The beam-column 1-D line element with fiber-type cross-section model is a practical option that yields results in agreement with experimental data. However, shortcomings of using this model to predict the local damage response may come from the fact that the model requires fine calibration of material properties to overcome regularization and size effects. To reduce the mesh-dependency of the numerical model, a regularization method based on the concept of post-yield energy is applied in this work to both the concrete and the steel material constitutive laws to predict the nonlinear cyclic response and failure mechanism of concrete shear walls. Different categories of wall specimens known to produce a different response under in plane cyclic loading for their varied geometric and detailing characteristics are considered in this study, namely: 1) scaled wall specimens designed according to the European seismic design code and 2) unique full-scale wall specimens detailed according to the U.S. design code to develop a ductile behavior under cyclic loading. To test the boundaries of application of the proposed method, two full-scale walls with a mixed shear-flexure response and different values of applied axial load are also considered. The results of this study show that the use of regularized constitutive models considerably enhances the response predictions capabilities of the model with regards to global force-drift response and failure mode. The simulations presented in this thesis demonstrate the proposed model to be a valuable tool for researchers and engineers.
Resumo:
In the crystal structure of the title compound (systematic name: 2,3-dichlorobenzene-1,4-diol 2,3-dichlorocyclohexa-2,5-diene-1,4-dione monohydrate), C(6)H(4)Cl(2)O(2)center dot C(6)H(2)Cl(2)O(2)center dot H(2)O, the 2,3-dichloro-1,4-hydroquinone donor (D) and the 2,3-dichloro-1,4-benzoquinone acceptor (A) molecules form alternating stacks along [100]. Their molecular planes [maximum deviations for non-H atoms: 0.0133 (14) (D) and 0.0763 (14) angstrom (A)] are inclined to one another by 1.45 (3)degrees and are thus almost parallel. There are pi-pi interactions involving the D and A molecules, with centroid-centroid distances of 3.5043 (9) and 3.9548 (9) angstrom. Intermolecular O-H center dot center dot center dot O hydrogen bonds involving the water molecule and the hydroxy and ketone groups lead to the formation of two-dimensional networks lying parallel to (001). These networks are linked by C-H center dot center dot center dot O interactions, forming a three-dimensional structure.
Resumo:
A practical method for the structural assignment of 3,4-O-benzylidene-D-ribono-1,5-lactones and analogues using conventional NMR techniques and NOESY measurements in solution is described. 2-O-Acyl-3,4-O-benzylidene-D-ribono-1,5-lactones were prepared in good yields by acylation of Zinner’s lactone with acyl chlorides under mildly basic conditions. Structural determination of 2-O-(4-nitrobenzoyl)-3,4-O-benzylidene-D-ribono-1,5-lactone was achieved by single crystal x-ray diffraction, which supports the results based on spectroscopic data.
Resumo:
Some antimicrobial peptides have a broad spectrum of action against many different kinds of microorganisms. Gomesin and protegrin-1 are examples of such antimicrobial peptides, and they were studied by molecular dynamics in this research. Both have a beta-hairpin conformation stabilized by two disulfide bridges and are active against Gram-positive and Gram-negative bacteria, as well as fungi. In this study, the role of the disulfide bridge in the maintenance of the tertiary peptide structure of protegrin-1 and gomesin is analyzed by the structural characteristics of these peptides and two of their respective variants, gomy4 and proty4, in which the four cysteines are replaced by four tyrosine residues. The absence of disulfide bridges in gomy4 and proty4 is compensated by overall reinforcement of the original hydrogen bonds and extra attractive interactions between the aromatic rings of the tyrosine residues. The net effects on the variants with respect to the corresponding natural peptides are: i) maintenance of the original beta-hairpin conformation, with great structural similarities between the mutant and the corresponding natural peptide; ii) combination of positive F and. Ramachandran angles within the hairpin head region with a qualitative change to a combination of positive (F) and negative (.) angles, and iii) significant increase in structural flexibility. Experimental facts about the antimicrobial activity of the gomesin and protegrin-1 variants have also been established here, in the hope that the detailed data provided in the present study may be useful for understanding the mechanism of action of these peptides.
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We enlarge the usual D = 3 N = 1 supergraph techniques to include the case of (explicitly or spontaneously) broken supersymmetric gauge theories. To illustrate the utility of these techniques, we calculate the two-loop effective potential of the SQED(3) by using the tadpole and the vacuum bubble methods. In these methods, to investigate the possibility of supersymmetry breaking, the superfields must be shifted by theta(alpha) dependent classical superfields (vacuum expectation values), what implies in the explicit breakdown of supersymmetry in the intermediate steps of the calculation. Nevertheless, after studying the minimum of the resulting effective potential, we find that supersymmetry is conserved, while gauge symmetry is dynamically broken, with a mass generated for the gauge superfield.
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In this work we study the dynamical generation of mass in the massless N = 1 Wess-Zumino model in a three-dimensional spacetime. Using the tadpole method to compute the effective potential, we observe that supersymmetry is dynamically broken together with the discrete symmetry A(x) -> A(x). We show that this model, different from nonsupersymmetric scalar models, exhibits a consistent perturbative dynamical generation of mass after two-loop corrections to the effective potential.
Resumo:
In the title compound, C(22)H(14)N(2)O(2), the five rings of the molecule are not coplanar. There is a significant twist between the four fused rings, which have a slightly arched conformation, and the pendant aromatic ring, as seen in the dihedral angle of 13.16 (8)degrees between the anthraquinonic ring system and the pendant aromatic ring plane.
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In this paper. we present the results of quantum dynamical simulations of the S (D-1) + H-2 insertion reaction on a newly developed potential energy surface (J. Chem. Phys. 2001, 114, 320). State-to-state reaction probabilities. product state distributions, and initial-state resolved cumulative reaction probabilities from a given incoming reactant channel are obtained from a time-independent wave packet analysis, performed within a single Lanczos subspace. Integral reaction cross sections are then estimated by J-shifting method and compared with the results from molecular beam experiment and QCT calculations.
Resumo:
Mushroom strains contain complex nutritional biomolecules with a wide spectrum of therapeutic and prophylactic properties. Among these compounds, β-d-glucans play an important role in immuno-modulating and anti-tumor activities. The present work involves a novel colorimetric assay method for β-1,3-d-glucans with a triple helix tertiary structure by using Congo red. The specific interaction that occurs between Congo red and β-1,3-d-glucan was detected by bathochromic shift from 488 to 516 nm (> 20 nm) in UV–Vis spectrophotometer. A micro- and high throughput method based on a 96-well microtiter plate was devised which presents several advantages over the published methods since it requires only 1.51 μg of polysaccharides in samples, greater sensitivity, speed, assay of many samples and very cheap. β-d-Glucans of several mushrooms (i.e., Coriolus versicolor, Ganoderma lucidum, Pleurotus ostreatus, Ganoderma carnosum, Hericium erinaceus, Lentinula edodes, Inonotus obliquus, Auricularia auricular, Polyporus umbellatus, Cordyseps sinensis, Agaricus blazei, Poria cocos) were isolated by using a sequence of several extractions with cold and boiling water, acidic and alkaline conditions and quantified by this microtiter plate method. FTIR spectroscopy was used to study the structural features of β-1,3-d-glucans in these mushroom samples as well as the specific interaction of these polysaccharides with Congo red. The effect of NaOH on triple helix conformation of β-1,3-d-glucans was investigated in several mushroom species.
Resumo:
Realizou-se estudo do tipo duplo anonimato em 18 pacientes com hepatite aguda benigna. O gruoo experimental foi testado com uma provável droga de ação antiviral: 1-BETA-D-RIBOFURANOSIL, 1,2,4-TRIAZOLE-3- CARBOXAMIDE. O grupo controle ingeriu um placebo de lactose. Teve-se especial cuidado na seleção de pacientes, incluindo apenas pacientes que preenchessem critérios bem estabelecidos. Os pacientes foram seguidos semanalmente, avaliando-os clínica e laboratorialmente. Os resultados não evidenciaram diferenças significativas entre os dois grupos, sugerindo-se estudos com casuística mais numerosa e em regime de internação hospitalar.