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Popular Abstract in Swedish Avhandlingen omfattar förutom en kort inledning, i huvudsak två delar: (1) Beskrivning av teorin bakom ett datorbaserat verktyg för simulering av termodynamiken i ett motorsystem, där främst motorer med Homogen Kompressionsantändning (Homogeneous Charge Compression Ignition, HCCI) avses. Med system avses förutom själva motorn, turboladdare, laddluftkylare, insug och avgThis thesis focuses on engine system simulation using thermodynamics and chemical kinetic models to investigate the performance and efficiency of Homogeneous Charge Compression Ignition (HCCI) engines for stationary applications. It includes the development of software as well as models for engine, turbocharger, intercooler, inlet and exhaust manifolds, wastegate valve, inlet air humidifier, inle

Background: Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor (GHSR), has two major functions: the stimulation of the growth hormone production and the stimulation of food intake. Accumulating evidence also indicates a role of ghrelin in cancer development. Methods: We conducted a case-control study to examine the association of common genetic variants in the genes coding

Material and methods: In all, 237 consecutive patients with a perforated peptic ulcer admitted from 1974-1992 and 125 consecutive patients with an oesophageal perforation admitted from 1970-2006 to Lund University hospital were studied retrospectively. Prognostic factors were evaluated using the Cox proportional hazards model. All cases of gastro-duodenal ulcer perforations diagnosed in Sweden fr

This thesis describes analysis of data from the DELPHI Very Small Angle Tagger (VSAT) calorimeter at LEP1. The VSAT consists of four Silicon-Tungsten calorimeter modules symmetrically positioned 7.7 meters away from the interaction point. It measures elastically scattered electrons and positrons, Bhabha events, within the polar angular region between 5-12 mrad. Trigger efficiency and reconstructio

Due to the nature of the engine cycle, heat transfer has a significant role in the estimation of engine efficiency. The effects are quite well known in the classic combustion concepts, compression ignition (CI) and spark ignition (SI) combustion. But for the newer, low temperature combustion (LTC) concepts, these effects are not that well known. In this paper, a commercial computational fluid dyna

Conventional power plants based on fossil fuel without CO2 capture produce flue gas streams with concentrations Of CO2 between 3% and 15%, contributing to the threat of increasing global warming. Existing capture technologies such as post-combustion flue gas treatment using chemical absorption or pre-combustion carbon removal suffer from significant efficiency penalties as well as major increase i

The concept of vandalism is analyzed as a symbolic act. An analysis of vandalism from a situational-positivistic, or a motivational-psychological, approach hardly gives an understanding of vandalism as a meaningful individual and social act. A humanistic and cultural perspective can supply ways to understand a nonprescribed behavior such as vandalism. The original meaning of vandalism is plunderin

According to conventional wisdom, improving energy efficiency is an easy way to mitigate climate change and improve energy security, though the reduction in energy intensity in developed economies is largely due to offshoring energy-intensive production to developing countries. This chapter presents a contrarian view. Theory, historical evidence, and time series analysis suggest that the economy-w

We present radial velocity follow-up observations of K2-19, a compact planetary system hosting three planets, of which the two larger ones, K2-19b and K2-19c, are close to the 3:2 mean motion resonance. An analysis considering only the radial velocity measurements detects K2-19b, the larger and more massive planet in the system, with a mass of 54.8 ± 7.5M⊕ and provides a marginal detection of K2-1

I here develop a specific version of the deflationary theory of truth. I adopt a terminology on which deflationism holds that an exhaustive account of truth is given by the equivalence between truth-ascriptions and de-nominalised (or disquoted) sentences. An adequate truth-theory, it is argued, must be finite, non-circular, and give a unified account of all occurrences of “true”. I also argue that

The coherent photoproduction of J/ψ and ψ′ mesons was measured in ultra-peripheral Pb–Pb collisions at a center-of-mass energy sNN−−−√ = 5.02 TeV with the ALICE detector. Charmonia are detected in the central rapidity region for events where the hadronic interactions are strongly suppressed. The J/ψ is reconstructed using the dilepton (l+l−) and proton–antiproton decay channels, while for the ψ′ t

Traditional fire alarms emit a high-frequency sound to alert the occupants of an imminent threat, which may be less appropriate for people who are deaf or hard of hearing. To address this issue, the scientific literature concerning alternative alarm technologies has been reviewed to evaluate their effectiveness in awakening people who are deaf or hard of hearing. The results show that low-frequenc

Square Kilometer Array (SKA) is a project aimed to build the largest radio telescope in the world and it has just gotten into the construction phase. In this phase, the ability to develop and integrate software in an integration environment is crucial as it is the ability to visualize system-related information via a User Interface to rapidly verify the correctness of the system behavior and spot

Background: Poor survival rates in different cancer types are sometimes blamed on diagnostic and treatment delays, and it has been suggested that such delays might be related to sociodemographic factors such as education and ethnicity. We examined associations of the wait time from diagnosis to surgery and survival in endometrial cancer (EC) and explored patient and tumour factors influencing the

The Historical Varieties of Democracy dataset (Historical V-Dem) contains about 260 indicators, both factual and evaluative, describing various aspects of political regimes and state institutions. The dataset covers 91 polities globally – including most large, sovereign states, as well as some semi-sovereign entities and large colonies – from 1789 to 1920 for many cases. The majority of the indica

Ultrafast X-ray absorption spectroscopy is a powerful tool to observe electronic and geometric structures of short-lived reaction intermediates. The ab initiofeff9 code is applied to simulate the Pt L3-edge XANES spectrum of the photocatalytic diplatinum molecule [Pt2(P2O5H2)4]4− and the photo-induced changes that occur therein. The spectra are interpreted within a XAFS-like scattering theoretical

OBJECTIVES: Acute Type A aortic dissection remains a life-threatening disease, but there are indications that its surgical mortality is decreasing. The aim of this report was to study how surgical mortality has changed and what influences those changes.METHODS: Nordic Consortium for Acute Type A Aortic Dissection is a retrospective database comprising 1159 patients (mean age 61.6 ± 12.2 years, 68%

Doping mechanisms of Mn in GaAs nanowires (NWs) that have been grown self-catalytically at 600 degrees C by molecular beam epitaxy (MBE) are investigated using advanced electron microscopy techniques and atom probe tomography, Mn is found to be incorporated primarily in the form of non-magnetic tetragonal Ga0.82Mn0.18 nanocrystals in Ga catalyst droplets at the ends of the NWs, while trace amounts