Full-wave electromagnetic modes and hybridization in nanoparticle dimers

The plasmon hybridization theory is based on a quasi-electrostatic approximation of the Maxwell’s equations. It does not take into account magnetic interactions, retardation effects, and radiation losses. Magnetic interactions play a dominant role in the scattering from dielectric nanoparticles. The retardation effects play a fundamental role in the coupling of the modes with the incident radiation and in determining their radiative strength; their exclusion may lead to erroneous predictions of the excited modes and of the scattered power spectra. Radiation losses may lead to a significant broadening of the scattering resonances. We propose a hybridization theory for non-Hermitian composite systems based on the full-Maxwell equations that, overcoming all the limitations of the plasmon hybridization theory, unlocks the description of dielectric dimers. As an example, we decompose the scattered field from silicon and silver dimers, under different excitation conditions and gap-sizes, in terms of dimer modes, pinpointing the hybridizing isolated-sphere modes behind them

Performance Comparison of Technological Solutions for Spark Applications in AWS

Cloud computing is providing a pay-as-you-go in-frastructure for the deployment of complex applications, with auto-scaling support and the ability to manage and process huge amount of data. However, due to the underlying complexity of the cloud infrastructure, it is not trivial to evaluate the setup providing the best performance of such scenario. To this aim the present paper proposes a thorough performance evaluation of a real application in a Cloud platform, measuring the impact of several design choices and technological solution. The experimental results, based on a real application and on realistic data can provide a significant insight that can integrate the traditional approach of cloud performance evaluation based on synthetic benchmarks

Lectin-binding sites in the seminal vesicles of entire and castrated horses

This research was undertaken to determine the glycoconjugates secreted by the glandular epithelium of the seminal vesicles in the entire and castrated horses using lectin histochemistry in combination with sialidase digestion and deglycosylation pre-treatments. The following lectins were used: Con-A, UEA-I, LTA, WGA, GSA-IB4, SBA, PNA, ECA and DBA. In the entire stallion, the glandular cells expressed the following sugar residues: a-Fuc, internal GlcNAc, terminal b- and a-GalNAc, b-D-Gal-(1-4)-GlcNAc and a-Gal included in O-linked oligosaccharides; b-Gal-(1-3)-GalNAc belonged to both O- and N-oligosaccharides whereas terminal GlcNAc to N-linked glycans. Additionally, a-Gal and b-Gal acted as acceptor sugars for sialic acid moieties. In castrated horses, the glandular epithelium showed a different lectin labelling pattern. In particular, we evidenced internal GlcNAc, a-GalNAc, b-Gal-(1-3)-GalNAc in both O- and N-linked glycoproteins whereas b-GalNAc and b-Gal-(1-3)-GalNAc in O-linked glycoproteins. The differences evidenced in the lectin profile between the stallion and castrated horse suggested an hormonal regulation of the glycoconjugate production. Additionally, the plurality of glycomolecules detected in the secretions of the stallion may be involved in spermatozoa maturatio

Lagrangian Variational Framework for Boundary Value Problems

A boundary value problem is commonly associated with constraints imposed on a system at its boundary. We advance here an alternative point of view treating the system as interacting "boundary" and "interior" subsystems. This view is implemented through a Lagrangian framework that allows to account for (i) a variety of forces including dissipative acting at the boundary; (ii) a multitude of features of interactions between the boundary and the interior fields when the boundary fields may differ from the boundary limit of the interior fields; (iii) detailed pictures of the energy distribution and its flow; (iv) linear and nonlinear effects. We provide a number of elucidating examples of the structured boundary and its interactions with the system interior. We also show that the proposed approach covers the well known boundary value problems.Comment: 41 pages, 3 figure

Efficient time-domain simulation of lossy multiconductor transmission lines by means of generalized method of characteristics

Abstract The paper investigates some crucial aspects in the derivation of time-domain equivalent circuits of lossy multiconductor transmission lines, obtained by using the generalized method of characteristic. The paper highlights how an exact evaluation of the effect of the propagation delays not only provide an accurate time-domain equivalent circuit, but suggests naturally the way to obtain a reduced-order model. The propagation is described correctly by means of damped delayed sources, while the effects of losses are efficiently taken into account by a low-order approximated lumped circuit. In this way it is easy to circumvent the main problems arising when using the generalized method of characteristic that is the correct evaluation of the impulse responses describing the time-domain model and the computational cost of the time-domain convolutions

Production of Giant \u3cem\u3ePanicum\u3c/em\u3e in Contrasting Environments in Semi-Arid Kenya

Giant panicum (Panicum maximum Jacq.) is a tall, vigorous perennial grass that is native to tropical and sub-tropical Africa. It is drought tolerant due to its deep and dense fibrous roots system and grows in a wide range of soil types. It is an important livestock feed and has been extensively cultivated in Brazil (Santos et al. 2006). Despite its wide genetic diversity in East Africa, its potential for livestock feed has not been exploited there due to limited research. Our research was aimed at evaluating the production of several giant panicum ecotypes in contrasting environments in semi-arid areas of Kenya