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Atmospheric chemistry of two biodiesel model compounds : Methyl propionate and ethyl acetate

The atmospheric chemistry of two C 4H 8O 2 isomers (methyl propionate and ethyl acetate) was investigated. With relative rate techniques in 980 mbar of air at 293 K the following rate constants were determined: k(C 2H 5C(O)OCH 3 + Cl) = (1.57 ± 0.23) × 10 -11, k(C 2H 5C(O) OCH 3 + OH) = (9.25 ± 1.27) × 10 -13, k(CH 3C(O)OC 2H 5 + Cl) = (1.76 ± 0.22) × 10 -11, and k(CH 3C(O)OC 2H 5 + OH) = (1.54 ±

Investigating the role of neural stem/progenitor regulators in the context of brain tumor development

Adult neural stem/progenitor cells (NSPs) are multipotent and self-renew over an extensive period of time. Transformation events in such cells, such as genetic or epigenetic alterations can result in brain tumors. One goal of research on brain tumors is to identify which regulators are impaired during tumor initiation, development and maintenance in order to understand the origin of brain tumors a

Mariyamma and the logic of realist explanation in sociology

Realism as a theory of science, in the view of the author of this paper, provides elegant solutions to several puzzles and dilemmas, not only in philosophy, but also to some of the most fundamental theorerical and methodological problems in social science. This paper introduces scien­tific realism, and presents one way of applying it to social science.

The Dynamics of Income-Related Health Inequalities in Australia versus Great Britain

This study compares the evolution of income-related health inequality (IRHI) in Australia (2001–2006) and in Great Britain (1999–2004) by exploring patterns of morbidity- and mortality-related health changes across income groups. Using Australian longitudinal data, the change in health inequality is decomposed into those changes related to health changes (income-related health mobility) and income

Fire Behaviour of Less-Combustible Dielectric Liquids in a Nuclear Facility

Transformers, modulators and other high voltage electrical equipment are traditionally filled with mineral oil, which serves as a coolant and dielectric insulator. A rising trend is observed globally towards the adoption of less-combustible, bio-degradable transformer liquids at ever increasing voltages and power ratings. This paper presents a study of the fire behavior of five different dielectri

How does tillage intensity affect soil organic carbon? A systematic review protocol

Background: Soils contain the greatest terrestrial carbon (C) pool on the planet. Since approximately 12 % of soil C is held in cultivated soils, management of these agricultural areas has a huge potential to affect global carbon cycling; acting sometimes as a sink but also as a source. Tillage is one of the most important agricultural practices for soil management and has been traditionally under

Kinetic isotope effects of 12CH3D+OH and 13CH3D+OH from 278 to 313K

Methane is the second most important long-lived greenhouse gas and plays a central role in the chemistry of the Earth's atmosphere. Nonetheless there are significant uncertainties in its source budget. Analysis of the isotopic composition of atmospheric methane, including the doubly substituted species 13CH3D, offers new insight into the methane budget as the sources and sinks have distinct isotop

Incidence and outcome of surgery for adult hydrocephalus patients in Sweden

Object: To present population-based and age related incidence of surgery and clinical outcome for adult patients operated for hydrocephalus, registered in the Swedish Hydrocephalus Quality Registry (SHQR). Methods: All patients registered in SHQR during 2004–2011 were included. Data on age, gender, type of hydrocephalus and type of surgery were extracted as well as three months outcome for patient

Influence of different SSF conditions on ethanol production from corn stover at high solids loadings

In this study, three different kinds of simultaneous saccharification and fermentation (SSF) of washed pretreated corn stover with water-insoluble solids (WIS) content of 20% were investigated to find which one resulted in highest ethanol yield at high-solids loadings. The different methods were batch SSF, prehydrolysis followed by batch SSF and fed-batch SSF. Batch-SSF resulted in an ethanol yiel

Ion beam evaluation of silicon carbide membrane structures intended for particle detectors

Thin ion transmission detectors can be used as a part of a telescope detector for mass and energy identification but also as a pre-cell detector in a microbeam system for studies of biological effects from single ion hits on individual living cells. We investigated a structure of graphene on silicon carbide (SiC) with the purpose to explore a thin transmission detector with a very low noise level

OH and Soot Optical Diagnostics for Combustion Applications for Combustion Applications

Optical diagnostics are remote non-intrusive sensing techniques. The thesis work concerns the use of OH and soot optical diagnostics for combustion research.Internal combustion (IC) engines are widely used for the generation of power and for transportation purposes. Soot emission, involving carbon particles that emanate from the combustion process, is one of major sources of pollutants in engine e

Can increased weathering rates due to future warming compensate for base cation losses following whole-tree harvesting in spruce forests?

Whole-tree harvesting, i.e. harvesting of stems, branches and tops, has become increasingly common during recent decades due to the increased demand for renewable energy. Whole-tree harvesting leads to an increase in base cation losses from the ecosystem, which can counteract recovery from acidification. An increase in weathering rates due to higher temperatures is sometimes suggested as a process

Prioritization guidelines for green food packaging development

Purpose: Current literature emphasizes using a holistic perspective on green packaging development (GPD) as an important strategy for reducing the environmental impact of products’ supply chain (SC). In practice, however, it can be difficult for packaging developers to strike a balance between all the different environmental requirements on packaging, and trade-offs are common. Life cycle assessme

Endothelium-dependent and-independent relaxation induced by resveratrol in rat superior mesenteric arteries

Resveratrol (Res) is a specific agonist of sirtuin 1, and has many cardioprotective effects. Although Res is able to relax various vascular beds, its pharmacological properties in rat superior mesenteric arteries and the underlying mechanism are not well clarified. The aim of present study was to investigate the vasorelaxant effects of Res on rat superior mesenteric arteries and the mechanisms inv

Head midline position for preventing the occurrence or extension of germinal matrix-intraventricular hemorrhage in preterm infants

Secondary objectives:Secondary objectives:P Primary objective: To assess whether head midline position compared with any other head position is more effective in prevention or extension of germinal matrix-intraventricular hemorrhage in infants born at ≤ 32 weeks' gestational age. Secondary objectives: To perform subgroup analyses regarding gestational age, birth weight, intubated versus not intuba

Variational approach to the structure and thermodynamics of linear polyelectrolytes with Coulomb and screened Coulomb interactions

A variational approach, based on a discrete representation of the chain, is used to calculate free energy and conformational properties in polyelectrolytes. The true bond and Coulomb potentials are approximated by a trial isotropic harmonic energy containing force constants between all monomer-pairs as variational parameters. By a judicious choice of representation and the use of incremental matri