Search results for "Particles"
showing 10 items of 8085 documents
The Chorioallantoic Membrane Assay in Nanotoxicological Research—An Alternative for In Vivo Experimentation
2020
Nanomaterials unveil many applicational possibilities for technical and medical purposes, which range from imaging techniques to the use as drug carriers. Prior to any human application, analysis of undesired effects and characterization of their toxicological profile is mandatory. To address this topic, animal models, and rodent models in particular, are most frequently used. However, as the reproducibility and transferability to the human organism of animal experimental data is increasingly questioned and the awareness of animal welfare in society increases at the same time, methodological alternatives are urgently required. The chorioallantoic membrane (CAM) assay is an increasingly popu…
From the Classical Boltzmann Equation to the Generalized Kinetic models of Biological Systems
2017
This paper deal with the classical Boltzmann Equation generalized to model populations in complex biological system. In particular, the populations refer to the cells of the immune system and to those of an aggressive host (cancer cells) in a human being. We will focus with the study of a spatially homogeneous continuous model, and derivation of the macroscopic model. The paper starts from a simple description of the classical Boltzmann equation and goes to the mathematical approach proposed to model the large systems of interacting entities focusing the competition between immune system and cancer cells.
Upper limits on the isotropic gravitational-wave background from Advanced LIGO and Advanced Virgo's third observing run
2021
We report results of a search for an isotropic gravitational-wave background (GWB) using data from Advanced LIGO's and Advanced Virgo's third observing run (O3) combined with upper limits from the earlier O1 and O2 runs. Unlike in previous observing runs in the advanced detector era, we include Virgo in the search for the GWB. The results are consistent with uncorrelated noise, and therefore we place upper limits on the strength of the GWB. We find that the dimensionless energy density $\Omega_{\rm GW}\leq 5.8\times 10^{-9}$ at the 95% credible level for a flat (frequency-independent) GWB, using a prior which is uniform in the log of the strength of the GWB, with 99% of the sensitivity comi…
(2010). Microstructure and magnetic properties of colloidal cobalt nano-clusters.
2010
The magnetic response of nanometer sized Co nanoparticles (NP) prepared using reverse micelle solutions are presented. The use of complementary structural and morphological probes (like transmission electron microscopy, high resolution electron microscopy, X-ray absorption spectroscopy) allowed to relate the magnetic properties to the size, morphology, composition and atomic structure of the nanoparticles. All data agree on the presence of a core–shell structure of NPs made of a metallic Co core surrounded by a thin Co-oxide layer. The core–shell microstructure of NPs affects its magnetic response mainly raising the anisotropy constant.
Functional CdSe and CdSe/ZnS nanoparticles capped with thiols: photophysical and photochemical properties and applications as sensors
2013
Esta tesis se centra en el efecto simbiótico entre los QDs de CdSe o CdSe/ZnS y sus ligandos orgánicos, y las ventajas de este efecto para mejorar la funcionalidad del QD y/o del ligando, o crear una nueva funcionalidad del sistema. Así : 1. la superficie de las nanopartícula recubierta con ligandos orgánicos puede permitir al QD i) permanecer estable en disolventes orgánicos o acuosos, debido a la repulsión estérica o iónica entre las nanopartículas, ii) mantener o aumentar sus propiedades emisivas (pasivación de los defectos de superficie, aumento de distancia entre nanopartícula y moléculas desactivadoras), y/o iii) para proporcionar funcionalidad a la nanopartícula. 2. la forma esférica…
Functionalization of nanoparticles in specific targeting and mechanism release
2017
The development of various nanotechnologies have provided a new field of research, which allows the manipulation of molecular components of matter and covers a vast array of nanodevices. The “smart” multifunctional nanostructures should work as customizable, targeted drug-delivery vehicles capable of carrying large doses of therapeutic agents into malignant cells. Some nanomedical approaches are based on the use of functionalized nanoparticles (NPs), not only to reduce toxicity and side effects of drugs but, also in potential the biological barriers crossing on, such as: the blood–brain barrier, different cellular compartments, including the nucleus. Currently, many materials are used for n…
The effective cross section for double parton scattering within a holographic AdS/QCD approach
2017
A first attempt to apply the AdS/QCD framework for a bottom-up approach to the evaluation of the effective cross section for double parton scattering in proton-proton collisions is presented. The main goal is the analytic evaluation of the dependence of the effective cross section on the longitudinal momenta of the involved partons, obtained within the holographic Soft-Wall model. If measured in high-energy processes at hadron colliders, this momentum dependence could open a new window on 2-parton correlations in a proton.
Search for Cosmic Neutrino Point Sources with Four Year Data of the ANTARES Telescope
2012
In this paper, a time-integrated search for point sources of cosmic neutrinos is presented using the data collected from 2007 to 2010 by the ANTARES neutrino telescope. No statistically significant signal has been found and upper limits on the neutrino flux have been obtained. Assuming an E ¿2 n; spectrum, these flux limits are at 1-10 ¿10¿8 GeV cm¿2 s¿1 for declinations ranging from ¿90° to 40°. Limits for specific models of RX J1713.7¿3946 and Vela X, which include information on the source morphology and spectrum, are also given.
A strong electroweak phase transition from the inflaton field
2016
We study a singlet scalar extension of the Standard Model. The singlet scalar is coupled non-minimally to gravity and assumed to drive inflation, and also couple sufficiently strongly with the SM Higgs field in order to provide for a strong first order electroweak phase transition. Requiring the model to describe inflation successfully, be compatible with the LHC data, and yield a strong first order electroweak phase transition, we identify the regions of the parameter space where the model is viable. We also include a singlet fermion with scalar coupling to the singlet scalar to probe the sensitivity of the constraints on additional degrees of freedom and their couplings in the singlet sec…
Status of Advanced Virgo
2017
The LIGO and the Virgo collaborations have recently announced the first detections of Gravitational Waves. Due to their weak amplitude, Gravitational Waves are expected to produce a very small effect on free-falling masses, which undergo a displacement of the order of 10-18 m for a Km-scale mutual distance. This discovery showed that interferometric detectors are suitable to reveal such a feeble effect, and therefore represent a new tool for astronomy, astrophysics and cosmology in the understanding of the Universe. To better reconstruct the position of the Gravitational Wave source and increase the signal-to-noise ratio of the events by means of multiple coincidence, a network of detectors…