Gastrointestinal function in intensive care patients: terminology, definitions and management. Recommendations of the ESICM Working Group on Abdominal Problems

Acute gastrointestinal (GI) dysfunction and failure have been increasingly recognized in critically ill patients. The variety of definitions proposed in the past has led to confusion and difficulty in comparing one study to another. An international working group convened to standardize the definitions for acute GI failure and GI symptoms and to review the therapeutic options

The Road Opens: From Escape to New Truth on the Road in American Literature

Travel and relocation have been integral parts of the American experience from the first known journeys of Leif Ericson five hundred years before Columbus. Since then, Europeans moved about the continent as explorers, and eventually Americans moved westward as part of Manifest Destiny and in search of the American Dream. When they finally reached the west coast, the journey doubled back on itself, forcing the journeyers to search the already developed land for the disappearing American Dream. However, regardless of their reason for departing the land they were on, the characters of many of the works of American fiction (and in the case of Into the Wild, non-fiction) were altered by their time on the road, resulting in their finding a new truth at the end of their journey. By examining the journeys in Herman Melville’s Moby-Dick, Mark Twain’s Adventures of Huckleberry Finn, F. Scott Fitzgerald’s The Great Gatsby, John Steinbeck’s The Grapes of Wrath, Jack Kerouac’s On the Road, Arthur Miller’s Death of a Salesman, Barbara Kingsolver’s The Bean Trees, and Jon Krakauer’s Into the Wild, this paper examines the reasons for the journey or movement, the encounters with falsehood and hypocrisy, and the discovery of new understandings or truths at the end of their journeys

Extraocular Muscle Reveals Selective Vulnerability of Type IIB Fibers to Respiratory Chain Defects Induced by Mitochondrial DNA Alterations

PURPOSE. The purpose of this study was to gain insights on the pathogenesis of chronic progressive external ophthalmoplegia, thus we investigated the vulnerability of five extra ocular muscles (EOMs) fiber types to pathogenic mitochondrial DNA deletions in a mouse model expressing a mutated mitochondrial helicase TWINKLE. METHODS. Consecutive pairs of EOM sections were analyzed by cytochrome C oxidase (COX)/succinate dehydrogenase (SDH) assay and fiber type specific immunohistochemistry (type I, IIA, IIB, embryonic, and EOM-specific staining). RESULTS. The mean average of COX deficient fibers (COX-) in the recti muscles of mutant mice was 1.04 +/- 0.52% at 12 months and increased with age (7.01 +/- 1.53% at 24 months). A significant proportion of these COX-fibers were of the fast-twitch, glycolytic type IIB (> 50% and > 35% total COX-fibers at 12 and 24 months, respectively), whereas embryonic myosin heavy chain-expressing fibers were almost completely spared. Furthermore, the proportion of COX-fibers in the type IIB-rich retractor bulbi muscle was > 2-fold higher compared to the M. recti at both 12 (2.6 +/- 0.78%) and 24 months (20.85 +/- 2.69%). Collectively, these results demonstrate a selective vulnerability of type IIB fibers to mitochondrial DNA (mtDNA) deletions in EOMs and retractor bulbi muscle. We also show that EOMs of mutant mice display histopathological abnormalities, including altered fiber type composition, increased fibrosis, ragged red fibers, and infiltration of mononucleated nonmuscle cells. CONCLUSIONS. Our results point to the existence of fiber type IIB-intrinsic factors and/or molecular mechanisms that predispose them to increased generation, clonal expansion, and detrimental effects of mtDNA deletions

Reactivity of Green Leaf Volatiles (GLVs) in the atmosphere: Kinetics, products and secondary organic aerosol formation

International audienceIn nature, plants can undergo many different stress phenomena. In response to biotic or abiotic stress factors, they will emit so called Green Leaf Volatiles (GLVs), which are part of the large group of biogenic volatile organic compounds (BVOC). Among the BVOCs unsaturated aldehydes are emitted in larger quantities from plants during stress periods; however, the understanding of their atmospheric reactivity is still very limited, particularly with respect to their impact on secondary organic aerosol (SOA) formation. Accordingly, the main objective of the present work is to investigate the fate of unsaturated aldehydes in the atmosphere focusing on SOA formation.In a first part, the kinetics of the reactions of trans-2-pentenal (T2P) and trans-2-hexenal (T2H) with O3 and Cl atoms was studied both in a Teflon chamber (0.3 m3) and in a Pyrex laminar flow reactor (O3 only) at the SAGE department.The second part was focused on the investigation of SOA formation during the ozonolysis of T2P and T2H in three different environmental chambers: the Teflon reactor mentioned above, the stainless steel CHARME (CHamber for Atmospheric Reactivity and Metrology of the Environment) at the LPCA (9.2 m3) and the quartz reactor QUAREC at the University of Wuppertal (1.1 m3). Parallel investigation of gaseous products by gas/liquid chromatography and IR spectroscopy was also carried out. Results will be discussed in terms of chemical mechanisms and the effect of the chamber

Particle Emissions from Aircraft Engines–A Survey of the European Project PartEmis

An overview of the goals and achievements of the European PartEmis project (Measurement and prediction of emissions of aerosols and gaseous precursors from gas turbine engines) is presented. PartEmis was focussed on the characterisation and quantification of exhaust emissions from a gas turbine engine. The engine was composed of a combustor and a unit to simulate a 3-shaft turbine section (so-called Hot End Simulator; HES). A comprehensive suite of aerosol, gas and chemi-ion measurements were conducted under different, i) combustor and HES operating conditions, ii) fuel sulphur concentrations. Measured aerosol properties were mass and number concentration, size distribution, mixing state, thermal stability of internally mixed particles, hygroscopicity, cloud condensation nuclei (CCN) activation potential, and chemical composition. Furthermore, chemi-ions, non-methane volatile organic compounds (NMVOCs) and OH were monitored. The combustor operation conditions corresponded to modern and older engine gas path temperatures at cruise altitude, with fuel sulphur contents (FSC) of 0.05, 0.41, and 1.270 g kg−1. The combustor behaved like a typical aircraft engine combustor with respect to thermodynamic data and main emissions, which suggests that the PartEmis database may be applicable to contemporary aircraft engines. The conclusions drawn from the PartEmis experiment are discussed separately for combustion particles, ultrafine particles, sulphate-containing species and chemi-ions, particle hygrioscopic growth and CCN activation, gaseous organic fraction, and emission properties

Réactivité de COVB oxygénés avec deux oxydants atmosphériques : O3 et Cl. Cinétiques, formation d’aérosols organiques secondaires et produits de réaction

International audienceLes émissions de composés organiques volatils d’origine biogénique (COVB) sont généralement supérieures d’un facteur dix aux émissions anthropiques. Le changement climatique entraine une augmentation des stress biotiques et abiotiques sur les plantes et induit des modifications dans les flux de COVB. Les aldéhydes insaturés sont des COVB dont les émissions sont renforcées en période de stress ; cependant, les connaissances sur leur réactivité atmosphérique sont encore très limitées, en particulier la formation des aérosols organiques secondaires (AOS). C’est dans ce cadre que ce projet a été réalisé avec l’objectif d’apporter des informations indispensables sur le devenir atmosphérique des aldéhydes insaturés.Ce travail se subdivise en trois parties. Une première partie a été consacrée à la détermination des constantes cinétiques avec O3 et Cl du trans-2-pentenal (T2P) et du trans-2-hexenal (T2H) au moyen d'une chambre de simulation atmosphérique (CSA) souple en Téflon (300 L). Les cinétiques d’ozonolyse ont également été réalisées dans un réacteur à écoulement laminaire en Pyrex.Au cours de la deuxième partie, la formation des AOS à partir de l'ozonolyse des T2P et T2H a été étudiée dans deux réacteurs : la CSA en Téflon et la CSA CHARME (CHamber for Atmospheric Reactivity and Metrology of the Environment) du LPCA (réacteur en inox électropoli de 9,2 m3).La troisième partie a été consacrée à l'étude des produits d’ozonolyse à l'aide d’analyses par chromatographies HPLC et GC-MS, et par spectroscopie IRTF. Dans cette partie, c’est essentiellement la CSA en Téflon qui a été utilisée. Des résultats préliminaires du réacteur cylindrique en quartz QUAREC de l'Université de Wuppertal (Allemagne) seront présentés

Drawing down N2O to protect climate and the ozone layer. A UNEP Synthesis Report

Nitrous oxide is a potent pollutant that has both ozone layer-damaging properties and the ability to contribute to climate change. This dual characteristic makes nitrous oxide a gas that needs to be targeted for emissions reduction. This is especially the case, since its emission has been increasing since the preindustrial era. However, it could be argued that not enough attention has been given to reducing nitrous oxide emissions. UNEP has therefore developed this report with the aim of informing policymakers and stakeholders about the impacts of nitrous oxide emissions on climate and ozone layer and to present available opportunities for reducing emissions. The report also articulates how efforts associated with reducing nitrous oxide emissions are closely linked to the concept of an inclusive “green economy”