Search results for "Aide"

Introduction to molecular topology: basic concepts and application to drug design.

2012

In this review it is dealt the use of molecular topology (MT) in the selection and design of new drugs. After an introduction of the actual methods used for drug design, the basic concepts of MT are defined, including examples of calculation of topological indices, which are numerical descriptors of molecular structures. The goal is making this calculation familiar to the potential students and allowing a straightforward comprehension of the topic. Finally, the achievements obtained in this field are detailed, so that the reader can figure out the great interest of this approach.

Twofold coordinated Ge defects induced by gamma-ray irradiation in Ge-doped SiO2

2008

We report an experimental study by photoluminescence, optical absorption and Electron Paramagnetic Resonance measurements on the effects of exposure of Ge-doped amorphous SiO2 to gamma ray radiation at room temperature. We have evidenced that irradiation at doses of the order of 1 MGy is able to generate Ge-related defects, recognizable from their optical properties as twofold coordinated Ge centers. Until now, such centers, responsible for photosensitivity of Ge-doped SiO2, have been induced only in synthesis procedures of materials. The found result evidences a role played by gamma radiation in generating photosensitive defects and could furnish a novel basis for photosensitive pattern wr…

The FiR 1 photon beam model adjustment according to in-air spectrum measurements with the Mg(Ar) ionization chamber.

2014

Abstract The mixed neutron–photon beam of FiR 1 reactor is used for boron–neutron capture therapy (BNCT) in Finland. A beam model has been defined for patient treatment planning and dosimetric calculations. The neutron beam model has been validated with an activation foil measurements. The photon beam model has not been thoroughly validated against measurements, due to the fact that the beam photon dose rate is low, at most only 2% of the total weighted patient dose at FiR 1. However, improvement of the photon dose detection accuracy is worthwhile, since the beam photon dose is of concern in the beam dosimetry. In this study, we have performed ionization chamber measurements with multiple b…

Filtered circular fingerprints improve either prediction or runtime performance while retaining interpretability

2016

Harmonic solution of semiconductor transport equations for microwave and millimetre-wave device modelling

2004

The transport equations for charges in a semiconductor have been solved for a periodic voltage excitation by means of a harmonic approach, for modelling of microwave and millimetre-wave active devices. The solution is based on the expansion of the unknown physical quantities in Fourier series in the time domain, and on the discretisation in the space domain. A Waveform-Balance technique in the time domain is used to solve the resulting non-linear equations system. In this way the time step is determined only by Nyquist's sampling requirements at the operating frequency, irrespective of the relaxation times of the semiconductor. This approach allows for a longer time step, and therefore a sh…

High-visibility interference fringes with femtosecond laser radiation.

2009

We propose and experimentally demonstrate an interferometer for femtosecond pulses with spectral bandwidth about 100 nm. The scheme is based on a Michelson interferometer with a dispersion compensating module. A diffractive lens serves the purpose of equalizing the optical-path-length difference for a wide range of frequencies. In this way, it is possible to register high-contrast interference fringes with micrometric resolution over the whole area of a commercial CCD sensor for broadband femtosecond pulses.

Gamow-Teller strengths in proton-rich exotic nuclei deduced in the combined analysis of mirror transitions

2005

Isospin symmetry is expected for the T-z=+/- 1 -> 0 isobaric analogous transitions in isobars with mass number A, where T-z is the z component of isospin T. Assuming this symmetry, strengths of analogous Gamow-Teller (GT) transitions within A=50 isobars were determined from a high energy-resolution T-z=+1 -> 0, Cr-50(He-3,t)Mn-50 study at 0 degrees in combination with the decay Q value and lifetime from the T-z=-1 -> 0, Fe-50 ->Mn-50 beta decay. This method can be applied to other pf-shell nuclei and can be used to study GT strengths of astrophysical interest.

The CALMA system: an artificial neural network method for detecting masses and microcalcifications in digitized mammograms

2004

The CALMA (Computer Assisted Library for MAmmography) project is a five years plan developed in a physics research frame in collaboration between INFN (Istituto Nazionale di Fisica Nucleare) and many Italian hospitals. At present a large database of digitized mammographic images (more than 6000) was collected and a software based on neural network algorithms for the search of suspicious breast lesions was developed. Two tools are available: a microcalcification clusters hunter, based on supervised and unsupervised feedforward neural network, and a massive lesions searcher, based on a hibrid approach. Both the algorithms analyzed preprocessed digitized images by high frequency filters. Clini…

Mean-Field Game Modeling the Bandwagon Effect with Activation Costs

2015

This paper provides a mean-field game theoretic model of the bandwagon effect in social networks. This effect can be observed whenever individuals tend to align their own opinions to a mainstream opinion. The contribution is threefold. First, we describe the opinion propagation as a mean-field game with local interactions. Second, we establish mean-field equilibrium strategies in the case where the mainstream opinion is constant. Such strategies are shown to have a threshold structure. Third, we extend the use of threshold strategies to the case of time-varying mainstream opinion and study the evolution of the macroscopic system.

Sporta spēļu nacionālo čempionātu videotiešraižu pieprasījums un piedāvājums Latvijas interneta un televīzijas vidē

2015

Bakalaura darba ''Sporta spēļu nacionālo čempionātu videotiešraižu pieprasījums un piedāvājums Latvijas interneta un televīzijas vidē'' mērķis ir noskaidrot, cik liels ir mediju videotiešraižu piedāvājums un auditorijas pieprasījums pēc nacionālo sporta spēļu čempionātu translācijām, kā arī, kādi faktori ietekmē to, ka aizvien vairāk translāciju veido interneta tiešraižu kompānijas, bet tradicionālās televīzijas to dara retāk. Darba teorētiskā daļa ietver teoriju par pieprasījumu un piedāvājumu, televīzijas un jauno mediju ietekmi sporta dzīvē, kā arī auditorijas lomu sportā un mediju darbībā. Metodoloģija ietver ekspertu intervijas, sekundāro datu analīzi un dziļās intervijas ar sporta aud…