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The huge amount of data made available by the technologies for sequencing the human genome calls for sophisticated and automated analysis techniques. In this direction, the GOLAM framework has been developed within the scope of the GenData 2020 Project to enable multi-resolution analysis and mining of matches between genomic regions. In this paper we show how the GOLAM framework can be used for OLAP analysis of the mappings between regions and samples resulting from queries expressed in GMQL against repositories of genomic data. In particular we show the multidimensional schema that represents mappings and we briefly address the main research challenge implied by GOLAM, i.e., on-demand ETL.

Many methods have been developed to analyze protein primary sequences or overall tertiary structures since sequences and/or structures similarity may imply common functional characteristics or active properties. However, evolution can lead sequences to diverge or structures to change topology even though retaining surface determinants essential to protein function. In such cases sequence or structure comparisons could not be sufficient to identify functions and evolutionary relationships among proteins. On the other hand, protein surface comparisons could identify those functions determinants that are independent of sequence or 3D structure. Here, we propose an original approach for comparison of proteins based on pattern recognition on surfaces, which has the advantage of being unsupervised and not based on already known functional meanings. Our method initially determines homogeneous patches on the protein surfaces, considering electric potential, hydrophobicity and shape index as distinguishing features. Then, complex patterns, composed by sets of patches that assume a similar spatial arrangement in different proteins, are detected. The method has been tested on a benchmarck database of 98 protein domains. The database has been constructed starting from 4 reference protein domains that have been subjected to progressive surface aminoacids mutations. The domains have been correctly classified and the progressive distance beetwen proteins, due to mutations, has been emphasized.

In the present article we numerically investigated the magneto-optical behaviour of a sub-wavelength structure composed by a monolayer graphene and a metallic metasurface of optical resonators. Using this hybrid graphene-metal structure, a large increase of the non-reciprocal polarization rotation of graphene can be achieved over a broad range of terahertz frequencies. We demonstrate that the symmetry of the resonator geometry plays a key role for the performance of the system: in particular, increasing the symmetry of the resonator the non-reciprocal properties can be progressively enhanced. Moreover, the possibility to exploit the metallic metasurface as a voltage gate to vary the graphene Fermi energy allows the system working point to be tuned to the desired frequency range. Another peculiar result is the achievement of a structure able to operate both in transmission and reflection with almost the same performance, but in a different frequency range of operation. The described system is hence a sub-wavelength, tunable, multifunctional, effective non-reciprocal element in the terahertz region.

Resonators and the way they couple to external radiation rely on very different concepts if one considers devices belonging to the photonic and electronic worlds. The terahertz frequency range, however, provides intriguing possibilities for the development of hybrid technologies that merge ideas from both fields in novel functional designs. In this paper, we show that high-quality, subwavelength, whispering-gallery lasers can be combined to form a linear dipole antenna, which creates a very efficient, low-threshold laser emission in a collimated beam pattern. For this purpose, we employ a terahertz quantum-cascade active region patterned into two 19-μm-radius microdisks coupled by a suspended metallic bridge, which simultaneously acts as an inductive antenna and produces the dipole symmetry of the lasing mode. Continuous-wave vertical emission is demonstrated at approximately 3.5 THz in a very regular, low-divergence (±10°) beam, with a high slope efficiency of at least 160 mW A â '1 and a mere 6 mA of threshold current, which is ensured by the ultra-small resonator size (V RES/Î" 3 â ‰10 â '2). The extremely low power consumption and the superior beam brightness make this concept very promising for the development of miniaturized and portable THz sources to be used in the field for imaging and sensing applications as well as for exploring novel optomechanical intracavity effects.

In this work we show how a continuous wave, low threshold and well collimated terahertz laser source can be obtained by coupling two sub-wavelength whispering galleries quantum cascade optical resonators with a suspended metallic bridge.

By placing a material in close vicinity of a resonant optical element, its intrinsic optical response can be tuned, possibly to a wide extent. Here, we show that a graphene monolayer, spaced a few tenths of nanometers from a split ring resonator metasurface, exhibits a magneto-optical response which is strongly influenced by the presence of the metasurface itself. This hybrid system holds promises in view of thin optical modulators, polarization rotators, and nonreciprocal devices, in the technologically relevant terahertz spectral range. Moreover, it could be chosen as the playground for investigating the cavity electrodynamics of Dirac fermions in the quantum regime. By placing a material in close vicinity of a resonant optical element, its intrinsic optical response can be tuned, possibly to a wide extent. Here, we show that a graphene monolayer, spaced a few tenths of nanometers from a split ring resonator metasurface, exhibits a magneto-optical response which is strongly influenced by the presence of the metasurface itself. This hybrid system holds promises in view of thin optical modulators, polarization rotators, and nonreciprocal devices, in the technologically relevant terahertz spectral range. Moreover, it could be chosen as the playground for investigating the cavity electrodynamics of Dirac fermions in the quantum regime. (C) 2015 AIP Publishing LLC.