408 research outputs found
OBSERVING THE POLARIZED COSMIC MICROWAVE BACKGROUND FROM THE EARTH: SCANNING STRATEGY AND POLARIMETERS TEST FOR THE LSPE/STRIP INSTRUMENT
Detecting B-mode polarization anisotropies on large angular scales in the Cosmic Microwave Background (CMB) polarization pattern is one of the major challenges in modern observational cosmology since it would give us an important evidence in favor of the inflationary paradigm and would shed light on the physics of the very early Universe. Multi-frequency observations are required to disentangle the very weak CMB signal from diffuse polarized foregrounds originating by radiative processes in our galaxy. The \u201cLarge Scale Polarization Explorer\u201d (LSPE) is an experiment that aims to constrain the ratio between the amplitudes of tensor and scalar modes to r 48 0.03 and to study the polarized emission of the Milky Way. LSPE is composed of two instruments: SWIPE, a stratospheric balloon operating at 140, 210 and 240 GHz that will fly for two weeks in the Northern Hemisphere during the polar night of 2021, and STRIP, a ground-based telescope that will start to take data in early 2021 from the \u201cObservatorio del Teide\u201d in Tenerife observing the sky at 43 GHz (Q-band) and 95 GHz (W-band). In my thesis, I show the results of the unit-level tests campaign on the STRIP detectors that took place at \u201cUniversit\ue0 degli Studi di Milano Bicocca\u201d from September 2017 to July 2018, and I present the code I developed and the simulations I performed to study the STRIP scanning strategy. During the unit-level tests, more than 800 tests on 68 polarimeters have been performed in order to select the 55 (49 Q-band and 6 W-band) with the best performance in terms of central frequencies, bandwidths, noise temperatures, white noise levels, slopes and knee frequencies. The STRIP scanning strategy is based on spinning the telescope around the azimuth axis with constant elevation in order to overlap the SWIPE coverage maintaining a sensitivity of 1.6 \ub5K (on average) per sky pixels of 1\ub0. Individual sources will be periodically observed both for calibration and study purposes
Future challenges and recommendations
Rapid advances in information technology and telecommunications, and in particular mobile and wireless communications, converge towards the emergence of a new type of “infostructure” that has the potential of supporting a large spectrum of advanced services for healthcare and health. Currently the ICT community produces a great effort to drill down from the vision and the promises of wireless and mobile technologies and provide practical application solutions. Research and development include data gathering and omni-directional transfer of vital information, integration of human machine interface technology into handheld devices and personal applications, security and interoperability of date and integration with hospital legacy systems and electronic patient record. The ongoing evolution of wireless technology and mobile device capabilities is changing the way healthcare providers interact with information technologies. The growth and acceptance of mobile information technology at the point of care, coupled with the promise and convenience of data on demand, creates opportunities for enhanced patient care and safety. The developments presented in this section demonstrate clearly the innovation aspects and trends towards user oriented applications
A Distributed Algebra System for Time Integration on Parallel Computers
We present a distributed algebra system for efficient and compact
implementation of numerical time integration schemes on parallel computers and
graphics processing units (GPU). The software implementation combines the time
integration library Odeint from Boost with the OpenFPM framework for scalable
scientific computing. Implementing multi-stage, multi-step, or adaptive time
integration methods in distributed-memory parallel codes or on GPUs is
challenging. The present algebra system addresses this by making the time
integration methods from Odeint available in a concise template-expression
language for numerical simulations distributed and parallelized using OpenFPM.
This allows using state-of-the-art time integration schemes, or switching
between schemes, by changing one line of code, while maintaining parallel
scalability. This enables scalable time integration with compact code and
facilitates rapid rewriting and deployment of simulation algorithms. We
benchmark the present software for exponential and sigmoidal dynamics and
present an application example to the 3D Gray-Scott reaction-diffusion problem
on both CPUs and GPUs in only 60 lines of code
A language and development environment for parallel particle methods
We present the Parallel Particle-Mesh Environment (PPME), a domain-specific language (DSL) and development environment for numerical simulations using particles and hybrid particle-mesh methods. PPME is the successor of the Parallel Particle-Mesh Language (PPML), a Fortran-based DSL that provides high-level abstrac- tions for the development of distributed-memory particle-mesh simulations. On top of PPML, PPME provides a complete development environment for particle-based simu- lations usin state-of-the-art language engineering and compiler construction techniques. Relying on a novel domain metamodel and formal type system for particle methods, it enables advanced static code correctness checks at the level of particle abstractions, com- plementing the low-level analysis of the compiler. Furthermore, PPME adopts Herbie for improving the accuracy of floating-point expressions and supports a convenient high-level mathematical notation for equations and differential operators. For demonstration purposes, we discuss an example from Discrete Element Methods (DEM) using the classic
Silbert model to simulate granular flows
The EuResist expert model for customised HAART optimisation: 2010 update and extension to newest compounds
Potent Phototoxicity of Marine Bunker Oil to Translucent Herring Embryos after Prolonged Weathering
Pacific herring embryos (Clupea pallasi) spawned three months following the Cosco Busan bunker oil spill in San Francisco Bay showed high rates of late embryonic mortality in the intertidal zone at oiled sites. Dead embryos developed to the hatching stage (e.g. fully pigmented eyes) before suffering extensive tissue deterioration. In contrast, embryos incubated subtidally at oiled sites showed evidence of sublethal oil exposure (petroleum-induced cardiac toxicity) with very low rates of mortality. These field findings suggested an enhancement of oil toxicity through an interaction between oil and another environmental stressor in the intertidal zone, such as higher levels of sunlight-derived ultraviolet (UV) radiation. We tested this hypothesis by exposing herring embryos to both trace levels of weathered Cosco Busan bunker oil and sunlight, with and without protection from UV radiation. Cosco Busan oil and UV co-exposure were both necessary and sufficient to induce an acutely lethal necrotic syndrome in hatching stage embryos that closely mimicked the condition of dead embryos sampled from oiled sites. Tissue levels of known phototoxic polycyclic aromatic compounds were too low to explain the observed degree of phototoxicity, indicating the presence of other unidentified or unmeasured phototoxic compounds derived from bunker oil. These findings provide a parsimonious explanation for the unexpectedly high losses of intertidal herring spawn following the Cosco Busan spill. The chemical composition and associated toxicity of bunker oils should be more thoroughly evaluated to better understand and anticipate the ecological impacts of vessel-derived spills associated with an expanding global transportation network
EuCARE-hospitalised study protocol: a cohort study of patients hospitalised with COVID-19 in the EuCARE project
Background: Severe acute respiratory syndrome coronavirus 2 (SARS CoV-2), the virus responsible for coronavirus disease 2019 (COVID-19), can lead to hospitalisation, particularly in elderly, immunocompromised, and non-vaccinated or partially vaccinated individuals. Although vaccination provides protection, the duration of this protection wanes over time. Additional doses can restore immunity, but the influence of viral variants, specific sequences, and vaccine-induced immune responses on disease severity remains unclear. Moreover, the efficacy of therapeutic interventions during hospitalisation requires further investigation. The study aims to analyse the clinical course of COVID-19 in hospitalised patients, taking into account SARS-CoV-2 variants, viral sequences, and the impact of different vaccines. The primary outcome is all-cause in-hospital mortality, while secondary outcomes include admission to intensive care unit and length of stay, duration of hospitalisation, and the level of respiratory support required. Methods: This ongoing multicentre study observes hospitalised adult patients with confirmed SARS-CoV-2 infection, utilising a combination of retrospective and prospective data collection. It aims to gather clinical and laboratory variables from around 35,000 patients, with potential for a larger sample size. Data analysis will involve biostatistical and machine-learning techniques. Selected patients will provide biological material. The study started on October 14, 2021 and is scheduled to end on October 13, 2026. Discussion: The analysis of a large sample of retrospective and prospective data about the acute phase of SARS CoV-2 infection in hospitalised patients, viral variants and vaccination in several European and non-European countries will help us to better understand risk factors for disease severity and the interplay between SARS CoV-2 variants, immune responses and vaccine efficacy. The main strengths of this study are the large sample size, the long study duration covering different waves of COVID-19 and the collection of biological samples that allows future research. Trial registration: The trial has been registered on ClinicalTrials.gov. The unique identifier assigned to this trial is NCT05463380
A comparative study of adhesion of melanoma and breast cancer cells to blood and lymphatic endothelium
Background: Lymphovascular invasion (LVI) is an important step in the metastatic cascade; tumor cell migration
and adhesion to blood and lymphatic vessels is followed by invasion through the vessel wall and subsequent
systemic spread. Although primary breast cancers and melanomas have rich blood vascular networks, LVI is
predominately lymphatic in nature. Whilst the adhesion of tumor cells to blood endothelium has been extensively
investigated, there is a paucity of information on tumor cell adhesion to lymphatic endothelium.
Methods and Results: Breast cancer (MDA-MB-231 and MCF7) and melanoma (MeWo and SKMEL-30) cell
adhesion to lymphatic (hTERT-LEC and HMVEC dLy Neo) and blood (HUVEC and hMEC-1) endothelial cells
were assessed using static adhesion assays. The effect of inflammatory conditions, tumor necrosis factor-a
(TNF-a) stimulation of endothelial and tumor cells, on the adhesive process was also examined. In addition,
the effects of TNF-a stimulation on tumor cell migration was investigated using haplotaxis (scratch wound)
assays. Breast cancer and melanoma cells exhibited higher levels of adhesion to blood compared to lymphatic
endothelial cells ( p < 0.001). TNF-a stimulation of endothelial cells, or of tumor cells alone, did not significantly
alter tumor–endothelial cell adhesion or patterns.When both tumor and endothelial cells were stimulated with
TNF-a, a significant increase in adhesion was observed ( p < 0.01), which was notably higher in the lymphatic
cell models ( p < 0.001). TNF-a-stimulation of all tumor cell lines significantly increased their migration rate
( p < 0.01).
Conclusions: Results suggest that metastasis resultant from lymphatic vessel-tumor cell adhesion may be
modulated by cytokine stimulation, which could represent an important therapeutic target in breast cancer and
melanoma
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