Search results for "tilat"

Assessment of a single-acquisition imaging sequence for oxygen-sensitive (3)He-MRI.

2001

MRI of the lungs using hyperpolarized helium-3 (3He) allows the determination of intrapulmonary oxygen partial pressures (pO2). The need to separate competing processes of signal loss has hitherto required two different imaging series during two different breathing maneuvers. In this work, a new imaging strategy to measure pO2 by a single series of consecutive scans is presented. The feasibility of the method is demonstrated in three healthy human volunteers. Maps and histograms of intrapulmonary pO2 are calculated. Changes in the oxygen concentration of the inhaled gas mixture are well reproduced in the histograms. Monte Carlo (MC) simulations of the temporal evolution of 3He hyperpolariza…

Energy performance evaluation of a demo solar desiccant cooling system with heat recovery for the regeneration of the adsorption material

2012

Abstract Since July 2008, a Solar Desiccant Evaporative Cooling (DEC) system has been operating as a test plant at the solar laboratory of the Dipartimento di Energia (ex DREAM) of the University of Palermo. The system is composed of an air handling unit (AHU) designed for ventilation of the laboratory coupled with a radiant ceiling that provides most of the required sensible cooling/heating energy. Flat plate collectors deliver part of the regeneration heat of the desiccant wheel during the summertime and are used for space heating during the wintertime. The system was designed for high humidity loads because of the typical climate conditions at the site and the need to support a radiant c…

High-flow nasal therapy versus noninvasive ventilation in COPD patients with mild-to-moderate hypercapnic acute respiratory failure: study protocol f…

2019

Background Noninvasive ventilation (NIV) is indicated to treat respiratory acidosis due to exacerbation of chronic obstructive pulmonary disease (COPD). Recent nonrandomized studies also demonstrated some physiological effects of high-flow nasal therapy (HFNT) in COPD patients. We designed a prospective, unblinded, multicenter, randomized controlled trial to assess the noninferiority of HFNT compared to NIV with respect to the reduction of arterial partial pressure of carbon dioxide (PaCO2) in patients with hypercapnic acute respiratory failure with mild-to-moderate respiratory acidosis. Methods We will enroll adult patients with acute hypercapnic respiratory failure, as defined by arterial…

What can the concept of affective scaffolding do for us?

2020

The concept of affective scaffolding designates the various ways in which we manipulate the environment to influence our affective lives. In this article, I present a constructive critique of recent discussion on affective scaffolding. In Part 1, I summarize how the theories of situated mind and niche construction contribute to a multidimensional notion of scaffolding. In Part 2, I focus specifically on affective scaffolding and argue that current ambiguity over its distinctive criteria causes uncertainty as to how the concept can and should be used. In Part 3, I identify and examine two possible responses to the suggested state of conceptual ambiguity. The first, restrictive option is to k…

Pulmonologists, Mechanical Ventilation and Complementary Techniques

2014

MODELIZACIÓN MEDIANTE CFD DE PARA EVALUAR LA VENTILACIÓN EN UN EDIFICIO ARQUEOLÓGICO, DATOS PRELIMINARES.

2016

[EN] The present study addresses the influences of wind flow structure, as an important factor responsible of material damage (erosion contributing) on “Casa di Diana” Mithraeum, a roman building (130 A.D.) sited on Ostia Antica (archaeological site, Rome – Italy), through the Computational Fluid Dynamics (CFD) simulations and direct measurements for its verification and validation (V&V). In this preliminary work, we present results relating to 3D reconstruction (geometry of the entire building) and the mesh importing on Fluent software. In general, the data check confirms, with ±10%, a good agreement (model) between the numerical solutions and direct measurements data by portable sensor. F…

Indoor localization using time difference of arrival with UWB signals and unsynchronized devices

2020

Abstract Indoor location using radio frequency (RF) signals has been traditionally focused mainly on RSSI and fingerprint techniques, because methods based on time of arrival (ToA) or time difference of arrival (TDoA) were not suitable for measuring short distances. However, the release of the IEEE 802.15.4a standard, the emergence of commercial ultra wide band (UWB) transceivers that are compliant to this norm and the integration of high frequency oscillators have permitted the design of more accurate indoor localization systems using the RF signal transmission time. In this paper, we propose an indoor localization system based on TDoA for UWB. The method implements an only one way transmi…

Cardiopulmonary Exercise Testing in Patients with Chronic Heart Failure: Prognostic Comparison from Peak VO2 and VE/VCO2 Slope

2010

Background: Cardiopulmonary exercise testing with ventilatory expired gas analysis (CPET) has proven to be a valuable tool for assessing patients with chronic heart failure (CHF). The maximal oxygen uptake (peak V02) is used in risk stratification of patients with CHF. The minute ventilation-carbon dioxide production relationship (VE/VCO2 slope) has recently demonstrated prognostic significance in patients with CHF. Methods: Between January 2006 and December 2007 we performed CPET in 184 pts (146 M, 38 F, mean age 59.8 ± 12.9 years), with stable CHF (96 coronary artery disease, 88 dilated cardiomyopathy), in NYHA functional class II (n.107) - III (n.77), with left ventricular ejection frac…

Role of Sky-gardens in Improving Energy Performance of Tall Buildings

2018

Natural ventilation has been used as a passive strategy for many decades but only now its importance in tall buildings for addressing the issues of high energy usage and reducing carbon footprints is emerging. Sky-gardens can play an important role in successful implementation of natural ventilation through amplification of natural wind speeds. This study presents a state-of-the-art review on optimization of tall buildings energy performance through incorporation of sky-gardens. Pros and cons of use of natural ventilation for multi-story buildings are highlighted. Details of involved technical difficulties and barriers in the construction and operation process of sky-gardens are also given.…

Recent Developments in International Investment Law

2016

International investment law remains a fast evolving and vibrant field of law with ongoing and recently-concluded investment treaty negotiations continually altering the status quo. It is a system at a crossroads of reform, generally focused on safeguarding the right of the host state to regulate and on improving the investor-state dispute settlement (ISDS) mechanism. But reform may also come into play in more far-reaching ways and significant changes are likely to see the day in the near future. One such change concerns the institutional architecture of the resolution of investment disputes, with the possible establishment of a permanent investment court and/or the introduction of an appel…