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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
Vem äger kulturhistorien?
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
Svenska dilemmor uppdateras igen, Expertkommentar till integrationsbarometer 2005
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
Water flow through porous materials. P. 1, Methods of water transport measurements
Carrier frequency effects on path loss
To study the carrier frequency effects on path loss, measurements have been conducted at four discrete frequencies in the range 460-5100 MHz. The transmitter was placed on the roof of a 36 meters tall building and the receive antennas were placed on the roof of a van. Both urban and suburban areas were included in the measurement campaign. The results show that there is a frequency dependency, in
A comparison of sole carbon source utilization patterns and phospholipid fatty acid profiles to detect changes in the root microflora of hydroponically grown crops
Sole carbon source utilization (SCSU) patterns and phospholipid fatty acid (PLFA) profiles were compared with respect to their potential to characterize root-inhabiting microbial communities of hydroponically grown crops. Sweet pepper (Capsicum annum cv. Evident), lettuce (Lactuca sativa cv. Grand Rapids), and four different cultivars of tomato (Lycopersicon esculentum cvs. Gitana, Armada, Aromata
Sustainable Development: Implementation in Urban Water Systems
Popular Abstract in Swedish Hållbar utveckling är ett ofta använt begrepp, som många inte riktigt förstår eftersom det går på tvärs mot traditionella vetenskapliga begrepp som förutsägelse och styrning. Många vetenskapsmän har tolkat begreppet på sätt som gynnar den egna agendan. Dessa vantolkningar har lett till att begreppet inte kommit till användning i praktisk planering. Avhandlingen hävdar As Sustainable development, a widely used but poorly understood term, challenges traditional scientific values such as prediction and control, scientists have tried to manipulate the concept to promote their own particular agendas. Thus, it has suffered from misrepresentation which has prevented the concept from being fully implemented at a practical level. It is asserted that traditional fragmen
A Turbocharged Dual-Fuel HCCI Engine
A 6-cylinder truck engine is modified for turbocharged dual-fuel Homogeneous Charge Compression Ignition (HCCI) engine operation. Two different fuels, ethanol and n-heptane, are used to control the ignition timing. The objective of this study is to demonstrate high load operation of a full-size HCCI engine and to discuss some of the typical constraints associated with HCCI operation. This study pr
Bilden av Fakiren
Om hur illustratörer framställt den litterära gestalten "Falstaff, fakir". Utgör förkortad bearbetning av artikeln med samma titel i Fakirenstudier XIV (1999).