Search results for "Models"
showing 10 items of 8211 documents
Population of lead isotopes in binary reactions using a Rb 94 radioactive beam
2020
8 pags., 9 figs.
Exploiting Low-Cost 3D Imagery for the Purposes of Detecting and Analyzing Pavement Distresses
2020
Road pavement conditions have significant impacts on safety, travel times, costs, and environmental effects. It is the responsibility of road agencies to ensure these conditions are kept in an acceptable state. To this end, agencies are tasked with implementing pavement management systems (PMSs) which effectively allocate resources towards maintenance and rehabilitation. These systems, however, require accurate data. Currently, most agencies rely on manual distress surveys and as a result, there is significant research into quick and low-cost pavement distress identification methods. Recent proposals have included the use of structure-from-motion techniques based on datasets from unmanned a…
Preclinical models in oncological pharmacology: limits and advantages
2021
A wide range of experimental tumor models, each with distinct advantages and disadvantages, is nowadays available. Due to the inherent differences in their complexity and functionality, the choice of the model is usually dependent on the application. Thus, to advance specific knowledge, one has to choose and use appropriate models, which complexity is largely dependent on the hypotheses to test, that is on the objectives. Whatever the model chosen, the complexity of cancer is such that none of them will be able to fully represent it. In vitro tumor models have provided important tools for cancer research and still serve as low-cost screening platforms for drugs. The improved understanding o…
Gli Archivi Digitali e l'Antropologia Virtuale. Ricostruzione 3D di un cranio umano mediante la moderna tecnica della Fotogrammetria
2022
Modern digital archives mainly thanks to recent developments in 3D modelling by TAC, Laser Scanner and Photogrammetry are highy useful for easily storing and exchanging large amounts of data for both qualitative and quantitative studies. Photogrammetry is a versatile and inexpensive technique that starting from one or more sets of 2D digital images allows for high-resolution 3D models to be built. The protocol reported here allows users with different backgrounds to easily and quickly built accurate models of human skulls using minimal and inexpensive equipment by simply modifying only some of the default settings of the Agisoft-Metashape software. The photo acquisition and the workflow of …
In assenza di intervento. Rappresentazioni digitali di restauri virtuali
2015
La simulazione della realtà attraverso le tecniche di rappresentazione digitale viene oggi in aiuto dei restauratori poiché consente loro di verificare l’impatto di un restauro ancor prima di intervenire. Ciò può contribuire a evitare interventi troppo invasivi e a contenere errate pratiche che, a volte, irrimediabilmente cancellano le tracce originali. Il saggio analizza alcune esperienze di ricerca sull’illuminazione nei modelli virtuali che sono emblematiche di un approccio possibile. Le ricostruzioni tridimensionali digitali analizzate forniscono non solo le informazioni spaziali e dimensionali ma anche gli aspetti cromatici e le caratteristiche di illuminazione di un’architettura. Lo s…
PLLA scaffolds with controlled architecture as potential microenvironment for in vitro tumor model
2019
Abstract The "microenvironment" where a tumor develops plays a fundamental role in determining its progression, the onset of metastasis and, eventually, its resistance to therapies. Tumor cells can be considered more or less invasive depending both on the nature of the cells and on the site where they are located. Commonly adopted laboratory culture protocols for the investigation of tumor cells take usually place on standard two-dimensional supports. However, such cultures do not allow for reproduction of the biophysical properties of the tumor’s microenvironment, thus causing the cells to lose most of their relevant characteristics. In this work MDA-MB 231 breast cancer cells were cultiva…
A Geometrical Channel Model for MIMO Mobile-to-Mobile Fading Channels in Cooperative Networks
2009
This paper deals with the modeling and analysis of narrowband multiple-input multiple-output (MIMO) mobile- to-mobile (M2M) fading channels in relay-based cooperative networks. Non-line-of-sight (NLOS) propagation conditions are assumed in the transmission links from the source mobile station to the destination mobile station via the mobile relay. A stochastic narrowband MIMO M2M reference channel model is derived from the geometrical three-ring scattering model, where it is assumed that an infinite number of local scatterers surround the source mobile station, the mobile relay, and the destination mobile station. The complex channel gains associated with the new reference channel model are…
The Vibrio choleare haemolysin anion channel is required for cell vacuolation and death
2002
SummarySeveral strains of Vibrio cholerae secrete ahaemolytic toxin of 63kDa, termed V. cholerae cytolysin (VCC). This toxin causes extensive vacuo-lation and death of cells in culture and forms ananion-selective channel in planar lipid bilayers and incells. Here, we identify inhibitors of the VCC anionchannel and show that the formation of the anionchannel is necessary for the development of the vacuoles and for the cell death induced by this toxin. Using markers of cell organelles, we show that vacuoles derive from different intracellular com-partments and we identify the contribution of lateendosomes and of the trans -Golgi network in vacuolebiogenesis.Introduction The Gram-negative bact…
Constraining Uncertainty in Projected Gross Primary Production With Machine Learning
2020
The terrestrial biosphere is currently slowing down global warming by absorbing about 30% of human emissions of carbon dioxide (CO2). The largest flux of the terrestrial carbon uptake is gross primary production (GPP) defined as the production of carbohydrates by photosynthesis. Elevated atmospheric CO2 concentration is expected to increase GPP (“CO2 fertilization effect”). However, Earth system models (ESMs) exhibit a large range in simulated GPP projections. In this study, we combine an existing emergent constraint on CO2 fertilization with a machine learning approach to constrain the spatial variations of multimodel GPP projections. In a first step, we use observed changes in the CO2 sea…
Isovector and isoscalar spin-multipole giant resonances in the parent and daughter nuclei of double-β-decay triplets
2022
The strength distributions, including giant resonances, of isovector and isoscalar spin-multipole transitions in the commonly studied double-β-decay triplets are computed in the framework of the quasiparticle random-phase approximation (QRPA) using the Bonn-A two-body interaction in no-core single-particle valence spaces. The studied nuclei include the double-β parent and daughter pairs (76Ge, 76Se), (82Se, 82Kr), (96Zr, 96Mo), (100Mo, 100Ru), (116Cd, 116Sn), (128Te, 128Xe), (130Te, 130Xe), and (136Xe, 136Ba). The studied transitions proceed from the ground states to the Jπ=0−,1−,2− (spin-dipole transitions) and Jπ=1+,2+,3+ (spin-quadrupole transitions) excited states in these nuclei. Compa…