A note on the empirics of the neoclassical growth model

This paper shows that the widely used log-linearization of the neoclassical model of growth implies a relevant loss in terms of the ability of the model in replicating the patterns of convergence of an economy to its equilibrium level.

Euboean cults and myths outside Euboea: Poseidon and Briareos/Aigaion

Αυτό το άρθρο επικεντρώνεται στους ευβοϊκούς μύθους και λατρείες και έχει σκοπό να ερμηνεύσει καλύτερα δύο ενδιαφέροντα στοιχεία σχετικά με ένα κεντρικό / περιφερειακό θέμα: Ποσειδώνας και Βριάρεως. Εμφανίζονται στενά συνδεδεμένοι με τις θαλάσσιες διαδρομές που ξεκινούσαν από τρία σημαντικά κέντρα της Εύβοιας (Ερέτρια, Χαλκίδα και Κάρυστο) για τις κοντινές ή μακρινές ακτές της Μεσογείου κατά τη Γεωμετρική και Αρχαϊκή περίοδο. Θα προσπαθήσουμε να καταδείξουμε το πώς οι λατρείες των αποικιστών μπορούν να παρέχουν πληροφορίες σχετικά με τις άγνωστες λατρευτικές συνήθειες των μητροπόλεών τους, οι οποίες επίσης άλλαξαν εξαιτίας των νέων συνθηκών που συνάντησαν οι αποικιστές στο εξωτερικό. Επιπλέον, μια ανάλυση των δεδομένων θα καταδείξει τη σημασία της Χαλκίδας στη διάδοση των μύθων όπως του Βριάρεω / Αιγαίωνα και θα τονίσει τη σημασία της περαιτέρω διερεύνησης του ρόλου της Καρύστου

Role of p53 and CDKN2A Inactivation in Human Squamous Cell Carcinomas

p53 tumor suppressor gene is the most commonly mutated gene in human and mouse cancers. Disruption of the p53 and Rb pathways is a fundamental trend of most human cancer cells. Inactivation of CDKN2A can lead to deregulation of these two pathways. Genetic abnormalities in CDKN2A gene have been well documented in human melanoma but their involvement in human nonmelanoma skin cancer (NMSC) and in particular in squamous cell carcinoma (SCC) is less clear. Several studies have shown that human SCCs harbour unique mutations in the p53 gene as well as inactivation of the CDKN2A gene. While mutations in the p53 gene are induced by UV radiation and represent tumor initiating events, the majority of alterations detected in the CDKN2A gene do not appear to be UV-dependent. In conclusion, in addition to p53 mutations, silencing of the CDKN2A gene might play a significant role in SCC development

State-of-the-Art of Metamaterials: Characterization, Realization and Applications

Metamaterials is a large family of microwave structures that produces interesting ε and μ conditions with huge implications for numerous electromagnetic applications. Following a description of modern techniques to realize epsilon-negative, mu-negative and double-negative metamaterials, this paper explores recent literature on the use of metamaterials in hot research areas such as metamaterial-inspired microwave components, antenna applications and imaging. This contribution is meant to provide an updated overview of complex microwave engineering for the generation of different types of metamaterials and their application in topical electromagnetic scenarios

Computational LEED: computational thinking strategies and Visual Programming Languages to support environmental design and LEED credits achievement

Since environmental and energy issues and challenges continues to emerge as key global concerns, Green Building Certification Systems are becoming increasingly relevant in the construction industry. In this regard, LEED (Leadership in Energy and Environmental Design) is considered one of the most widely recognized environmental assessment methods used globally in the construction industry today. However, due to the high level of complexity of the LEED system, the tools usually used to verify the achievement of the credits lack of “design friendliness” and hardly communicate effectively with the conventional tools used by architects and engineers (e.g. CAD, BIM). This makes difficult to fully take into account, especially at the early design stage, the many interconnected aspects that contribute to the green certification, with consequent issues often arising in the design validation and/or construction phases, resulting in time delays and cost increments. The application of innovative problem-solving methods, such as computational thinking, together with coding techniques, represents an effective way to deal with this issue. This kind of methodology, in fact, allows the requirements of a specific LEED credit to be digitally parametrised and flexibly incorporated into a “designer friendly” working environment. In particular, Visual Programming Languages (VPLs), due to their high simplicity of usage, allow architects and engineers to develop algorithms and thus implement their technical knowledge in the field of environmental design with computer programming skills, useful to improve their tools and keep them constantly updated. The aim of this paper is to illustrate a methodology through which, by merging computational thinking strategies with VPL tools, is possible to keep under control, in the same working environment, all the parameters required to verify in real time the achievement of LEED credits. To demonstrate the flexibility of the approach, dedicated tools developed for the verification of some specific credits at different scales – neighbourhood and building – are illustrated as operational examples of the proposed methodology

Analysis and Characterization of Finite-size Curved Frequency Selective Surfaces

Frequency Selective Surfaces (FSSs) are spatial filters that are largely employed in radomes for radars and antennas where high performance is necessary. FSS can be categorised in terms of their frequency behaviour. Band-pass FSS structures are able to let the electromagnetic wave pass in certain frequency ranges and shield others, which are especially suitable for out-of-band stealth of radomes. The properties of frequency selectiveness of these screens are used at microwave and infrared wavelengths. By tuning the electrical size and geometry of the unit-cell (patch or aperture) different frequency behaviours of the structure are generated. Although their analysis and simulation is significantly simplified with the approximation of infinite and planar array, in some real applications FSS are required to be conformal to limited non-planar structures. The literature on the problem of characterizing finite-size and curved FSS has been sparse and more focused on the single application rather than on a unified approach. In the aim of synthesizing valuable techniques, this paper reviews significant research results on truncated and curved FSS which were presented in the dedicated literature

Numerical Investigation about Frequency Behaviour of Conformal FSS

Frequency selective surfaces (FSSs) are spatial filters widely employed in high-performance applications like hybrid radomes for radars and antennas. While planar geometries are widely studied, less attention has been devoted to conformal ones, where we must consider the influence of both the lattice geometry and the shape and size of the individual elements. In the planar case, periodicity first impacts on the general reflecting properties of the surface, while the shape and the size of the individual element affect its detailed both spatial and frequency filtering behaviour. In particular, the frequency response is dictated mainly by the scattering by the individual element and attains its maximum at resonance conditions. We mean to numerically investigate whether the same also occurs for non-planar surfaces and curved elements, for both cylindrical and conical surfaces. We compare the results of the general frequency behaviour of FSS both made of strips in free space and slots cut in a perfectly conducting material. The effect of the lattice geometrical parameters is also appreciated. The main conclusions are that also for curved elements a frequency selective behaviour can be appreciated and the interaction with the single elements plays an important role, when mutual coupling is not strong

The Dimension of Phaseless Near-Field Data by Asymptotic Investigation of the Lifting Operator

In this paper, the question of evaluating the dimension of data space in an inverse source problem from near-field phaseless data is addressed. The study is developed for a 2D scalar geometry made up by a magnetic current strip whose square magnitude of the radiated field is observed in near non-reactive zone on multiple lines parallel to the source. With the aim of estimating the dimension of data space, at first, the lifting technique is exploited to recast the quadratic model as a linear one. After, the singular values decomposition of such linear operator is introduced. Finally, the dimension of data space is evaluated by quantifying the number of “relevant” singular values. In the last part of the article, some numerical simulations that corroborate the analytical estimation of data space dimension are shown