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A system perspective on the heating of detached houses

Primary energy use, emission and the cost of whole energy system chains, from natural resource to end-User, were analysed, in a Swedish context,, hen heating detached houses. Both electricity-based systems employing heat Pumps. boilers. or resistance heaters. and local fuel-based systems (e.g. natural gas. oil and wood fuel) were considered. The base-load electricity was Produced in stand-alone po

Coupled cluster/molecular mechanics method: Implementation and application to liquid water.

In this paper, we present theory and implementation of the first method which combines coupled cluster and molecular mechanics (CC/MM) theory. By introducing the interactions between the solute (QM) and the solvent (MM) molecules into a coupled cluster Lagrangian, we calculate interaction and solvation energies of condensed phase molecules. Also, we derive a hierarchy in the coupling between the t

Trace gas exchange in a high-arctic valley 1. Variations in CO2 and CH4 flux between tundra vegetation types

Ecosystem exchanges of CO2 and CH4 were studied by chamber techniques in five different vegetation types in a high arctic valley at Zackenberg, NE Greenland. The vegetation types were categorized as Cassiope heath, hummocky fen, continuous fen, grass land and Salix arctica snowbed. Integrated daytime fluxes for the different vegetation types of the valley showed that the fen areas and the grasslan

Spectral Compensation for Multicarrier Communication

Spectral compensation is an information-processing technique applied in the transmitter to improve the spectral efficiency of multicarrier modulation under a given power spectral density constraint. A set of carefully chosen tones, the so-called information tones, carries data. The. remaining tones, referred to as compensation tones, are modulated with a linear combination of the data, such that t

DNA-lipid systems. An amphiphile self-assembly and polymer-surfactant perspective

The interaction between DNA and oppositely charged surfactants has been investigated by several techniques, like fluorescence microscopy, electron microscopy, phase diagram determination, and ellipsometry. The phase behaviour is more strongly associative than that in previously studied systems. A precipitate is formed for very low amounts of surfactant and DNA. DNA compaction is a general phenomen

Radiographic joint destruction in postmenopausal rheumatoid arthritis is strongly associated with generalised osteoporosis.

Objectives: To investigate determinants of joint destruction and reduced bone mineral density (BMD) in postmenopausal women with active rheumatoid arthritis (RA) not treated with bisphosphonates or hormone replacement therapy and to evaluate if there are common markers of erosive disease and bone loss. Methods: BMD was measured using dual x ray absorptiometry and joint damage was examined by x ra

Increased photoreactivity of DOC by acidification: Implications for the carbon cycle in humic lakes

Effects of ultraviolet (UV)-B radiation and acidification on pelagic carbon flux in a humic lake (dissolved organic carbon [DOC] similar to15 mg C L-1) were studied in a mesocosm experiment during the summer of 2000. Triplicate tanks (107 liters volume, 1 m high) were exposed to natural solar radiation, a daily extra dose of UV-B radiation, or kept dark. One set of tanks was submitted to a decreas

Microbial degradation of acetonitrile using a suspended-carrier biofilm process

A microbial process for the destruction of acetonitrile has been developed. Suitable microorganisms were enriched from activated sludge by cultivation with a high selection pressure when acetonitrile was the sole source of carbon and nitrogen. The process is based on cultivating the microorganisms as a biofilm on plastic carriers. These are utilised in a stirred-tank reactor with continuous feedin

Bi-enzyme biosensor based on NAD(+)- and glutathione-dependent recombinant formaldehyde dehydrogenase and diaphorase for formaldehyde assay

The present work reports on the development of a bi-enzyme biosensor using diaphorase from Bacillus stearothermophilus, nicotinamide adenine dinucleotide (NAD(+))- and glutathione (GSH)-dependent formaldehyde dehydrogenase (FDH) from the genetically-engineered methylotrophic yeast Hansenula polymorpha as bio-recognition elements. The sensor architecture comprises a first layer containing diaphoras

Ultrafast excited-state isomerization dynamics of 1,1 '-diethyl-2,2 '-cyanine studied by four-wave mixing spectroscopy

Excited-state dynamics and solvent-solute interactions of 1,1'-diethyl-2,2'-cyanine iodine (1122C) in alcoholic solutions are investigated using time-integrated three-pulse photon-echo spectroscopy. 1122C serves as a model compound for ultrafast photoinduced isomerizationa key process in the light reception of plants, bacteria, and human vision. The photoreaction in 1122C is interrogated in depend

InAs nanowires grown by MOVPE

Epitaxial growth of Au-assisted InAs nanowires using metal organic vapour phase epitaxy is investigated. The growth rate and morphology of nanowires as a function of growth temperature, substrate material and precursor flows are discussed. It is observed that tapering increases with both In and As precursor flows, but decreases with temperature. Finally, we report growth of InAs nanowires on both

Renal replacement therapy in Sweden

Objective: The Swedish Registry for Active Treatment of Uraemia (SRAU) was founded in 1991 with the objective of documenting demographic data on patients treated for end-stage renal disease (ESRD). The aim of this study was to describe the prevalence, incidence, comorbidity risk factors and survival of patients with ESRD who underwent dialysis treatment and/or kidney transplantation in Sweden betw

Community assembly and seasonal succession of marine dinoflagellates in a temperate estuary: The importance of life cycle events

Dinoflagellate successional strategies and community structure were investigated in Perch Pond, a temperate estuary on the North American east coast by field surveys as well as laboratory investigations on growth rates, cyst maturation period, and cyst germination temperature thresholds. The dominant species were those predicted by the Smayda and Reynolds Rules of Assembly life form model. Three s

The Swedish knee arthroplasty register. A nation-wide study of 30,003 knees 1976-1992

1976 through 1992, 30,003 primary knee arthroplasties and their revisions have been recorded in a nation-wide Swedish study. We report on the structure of the register, demographic data and survivorship. We found that operations for osteoarthrosis (OA) counted for the increase in number of arthroplasties in contrast to rheumatoid arthritis (RA), where the number had slightly declined. For primary