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Measurement of gasoline exhaust particulate matter emissions with a wide-range EGR in a heavy-duty diesel engine

A large number of measurement techniques have been developed or adapted from other fields to measure various parameters of engine particulates. With the strict limits given by regulations on pollutant emissions, many advanced combustion strategies have been developed towards cleaner combustion. Exhaust gas recirculation (EGR) is widely applied to suppress nitrogen oxide (NOx) and reduce soot emiss

Effect of injection timing on the ignition and mode of combustion in a HD ppc engine running low load

This work aims to study the effect of fuel inhomogeneity on the ignition process and subsequent combustion in a compression ignition Partially Premixed Combustion (PPC) engine using a primary reference fuel (PRF) in low load conditions. Five cases with injection timings ranging from the start of injection (SOI) at -70 crank angle degrees (CAD) to -17 CAD have been studied numerically and experimen

Study on heat losses during flame impingement in a diesel engine using phosphor thermometry surface temperature measurements

In-cylinder heat losses in diesel engines decrease engine efficiency significantly and account for approximately 14-19% [1, 2, 3] of the injected fuel energy. A great part of the heat losses during diesel combustion presumably arises from the flame impingement onto the piston. Therefore, the present study investigates the heat losses during flame impingement onto the piston bowl wall experimentall

Comparison of kinetic mechanisms for numerical simulation of methanol combustion in dici heavy-duty engine

The combustion process in a homogeneous charge compression ignition (HCCI) engine is mainly governed by ignition wave propagation. The in-cylinder pressure, heat release rate, and the emission characteristics are thus largely driven by the chemical kinetics of the fuel. As a result, CFD simulation of such combustion process is very sensitive to the employed reaction mechanism, which model the real

Cylinder to cylinder variation related to gas injection timing on a dual-fuel engine

The natural gas/diesel dual-fuel engine is an interesting technique to reduce greenhouse gas emission. A limitation of this concept is the emission of un-combusted methane. In this study we analyzed the influence of PFI gas-injection timing on cylinder to cylinder gas-distribution, and the resulting methane emissions. This was done on a 6 cylinder HD engine test bench and in a GT-power simulation

The WNT5A Agonist Foxy5 Reduces the Number of Colonic Cancer Stem Cells in a Xenograft Mouse Model of Human Colonic Cancer

BACKGROUND: The wingless-type mammary tumour virus integration site 5A (WNT5A) agonist Foxy5 was shown in vitro to affect intracellular signalling implicated in the regulation of colonic cancer stem cells (CSCs). MATERIALS AND METHODS: In order to study whether Foxy5 can modulate CSCs, either HT-29 or Caco-2 human colonic cancer cells, both lacking endogenous WNT5A expression, were inoculated subc

The Emerging Role of Calcium-activated Chloride Channel Regulator 1 in Cancer

Calcium-activated chloride channel regulator 1 (CLCA1) belongs to a group of secreted self-cleaving proteins, which activate calcium-dependent chloride channels. CLCA1 has been shown to participate in the pathogenesis of inflammatory airway diseases such as asthma. Recently, additional functions of CLCA1 have been unveiled, including its metalloprotease property and involvement in mucus homeostasi

Refinement of protein structures using a combination of quantum-mechanical calculations with neutron and X-ray crystallographic data

Neutron crystallography is a powerful method to determine the positions of H atoms in macromolecular structures. However, it is sometimes hard to judge what would constitute a chemically reasonable model, and the geometry of H atoms depends more on the surroundings (for example the formation of hydrogen bonds) than heavy atoms, so that the empirical geometry information for the H atoms used to sup

Angelic humans, glorious flesh : Jerome's reception of Origen's teachings on the resurrection body

One of the most important theological questions in the first Origenist controversy was that of the resurrection of the dead. Jerome accused both Origen and contemporary “Origenists” of speaking only of the resurrection of the body, and not of the flesh, and he claimed that an idea of resurrection without the flesh could not guarantee the identity between the body living on earth and the resurrecte

MEK1/2 inhibitor U0126, but not nimodipine, reduces upregulation of cerebrovascular contractile receptors after subarachnoid haemorrhage in rats

Vascular pathophysiological changes after haemorrhagic stroke, such as phenotypic modulation of the cerebral arteries and cerebral vasospasms, are associated with delayed cerebral ischemia (DCI) and poor outcome. The only currently approved drug treatment shown to reduce the risk of DCI and improve neurologic outcome after aneurysmal subarachnoid haemorrhage (SAH) is nimodipine, a dihydropyridine

Calculated arterial blood gas values from a venous sample and pulse oximetry : Clinical validation

Background Arterial blood gases (ABG) are essential for assessment of patients with severe illness, but sampling is difficult in some settings and more painful than for peripheral venous blood gas (VBG). Venous to Arterial Conversion (v-TAC; OBIMedical ApS, Denmark) is a method to calculate ABG values from a VBG and pulse oximetry (SpO 2 ). The aim was to validate v-TAC against ABG for measuring

Prognostic performance of preoperative cardiac troponin and perioperative changes in cardiac troponin for the prediction of major adverse cardiac events and mortality in noncardiac surgery : A systematic review and meta-analysis

Background Increased postoperative cardiac troponin (cTn) independently predicts short-term mortality. Previous studies suggest that preoperative cTn also predicts major adverse cardiovascular events (MACE) and mortality after noncardiac surgery. The value of preoperative and perioperative changes in cTn as a prognostic tool for adverse outcomes has been sparsely investigated. Methods and findings

Luftkvalitén i barns utemiljö – en kunskapsinventering

På uppdrag av Naturvårdsverket har avdelningen för Arbets- ochmiljömedicin vid Lunds Universitet utfört en kunskapsinventering blandlandets kommuner kring luftkvalitén på förskolebarns utemiljöer ocheffekter/strategier för att eventuellt förbättra detta. Denna inventeringgenomfördes under hösten 2018 och början av 2019 och ska ligga till grundför det Hälsorelaterade Miljöövervaknings projektet ”Lu

1.57 µm fiber source for atmospheric CO 2 continuous-wave differential absorption lidar

We present an efficient fiber source designed for continuous-wave differential absorption light detection and ranging (CW DIAL) of atmospheric CO 2 -concentration. It has a linewidth of 3 MHz, a tuning range of 2 nm over the CO 2 absorption peaks at 1.572 µm, and an output power of 1.3 W limited by available pump power. Results from the initial CW DIAL testing are also presented and discussed.

Luftmätningar i barns utemiljö – ett Citizen Science projekt vid Malmö förskolor

Denna rapport redovisar resultaten från ett pilotprojekt i ett större EU baserat Citizen Science projektsom initierats av EEA (European Environmental Agency Area) och ska bidra med kunskap om hurett större Citizen Science projekt kan organiseras när det gäller utskick av information ochutdelning/uppsamling av mätutrustning för luftkvalitetmätningar.Studien är finansierad av Naturvårdsverket och sy

Extreme high field plasmonics : Electron acceleration and XUV harmonic generation from ultrashort surface plasmons

Experiments on the excitation of propagating surface plasmons (SPs) by an ultrashort, high intensity laser interaction with grating targets are reviewed. At intensities exceeding 10 19 W cm -2 on target, i.e., in the strongly relativistic regime of electron dynamics, multi-megaelectronvolt electrons are accelerated by the SP field as dense bunches collimated in a near-tangent direction. By the