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The carotenoid S-1 state in LH2 complexes from purple bacteria Rhodobacter sphaeroides and Rhodopseudomonas acidophila: S-1 energies, dynamics, and carotenoid radical formation

Using near-infrared femtosecond absorption spectroscopy, we have determined the S-1 energies of the carotenoids spheroidene and rhodopin glucoside in LH2 complexes of purple bacteria. The S-1 energies in the LH2 complexes yield values of 13400 +/- 100 cm(-1) for spheroidene and 12550 +/- 150 cm(-1) for rhodopin glucoside, which are very close to the S-1 energies obtained for both carotenoids in so

Calcium binding to the first EGF-like module of human factor IX in a recombinant fragment containing residues 1-85. Mutations V46E and Q50E each manifest a negligible increase in calcium affinity

The first EGF-like module of human coagulation factor IX contains a single functionally important calcium ion binding site. We have now shown the dissociation constant for this site to be approximately 160 microM in a recombinant protein fragment consisting of residues 1-85 in human fIX. This represents a approximately 10-fold increase in affinity as compared with the isolated EGF module (residues

Flexible lock-in detection system based on synchronized computer plug-in boards applied in sensitive gas spectroscopy

We present a flexible and compact, digital, lock-in detection system and its use in high-resolution tunable diode laser spectroscopy. The system involves coherent sampling, and is based on the synchronization of two data acquisition cards running on a single standard computer. A software-controlled arbitrary waveform generator is used for laser modulation, and a four-channel analog/digital board r

Youth - the future manpower. Studies on unemployment, quality of life and work attitudes.

Popular Abstract in Swedish Arbetslivet är en av de viktigaste delarna i människors livssituation och ett av de viktigaste incitamenten för välfärden i ett samhälle. Stora förändringar har skett för ungdomar beträffande arbetslivet och inträdet i arbetslivet under de senaste decennierna. Bl.a. de stora förändringarna gör att ny kunskap krävs för att ge möjlighet att stärka ungdomarna i deras inträThe aim was to gain knowledge of experiences of unemployment in young adults with special regard to quality of life (QOL) and to highlight work attitudes and related factors among adolescents. Three studies were performed in Kristianstad municipality, Sweden. In Study 1, a questionnaire was sent in 1998 to 264 unemployed young adults (md=22 years, range 20?25) and to a control group of 528 random

Praktikfall i reglerteknik - Råspritbränneriet i Nöbbelöv

Vårterminen 98 gav Institutionen för Reglerteknik doktorandkursen Praktikfall i reglerteknik. Kursen bestod av ett projektarbete på en industri med reglertillämpningar. Den här rapporten redovisar resultatet av ett arbete på råspritbränneriet i Nöbbelöv, där basen för brännvinet Absolut Vodka tillverkas. Bränneriet hade problem med fluktuationer i koncentrationen av etanol i råspriten. ProjektgrupDuring spring 1998 the course Industrial Case Studies in Control was given at the Department of Automatic Control in Lund. The course consisted of a project at an industry with control applications. This report considers a project at the crude alcohol distillery in Nöbbelöv, where the base product for the liquor Absolut Vodka is produced. The distillery had problems with fluctuations in the concen

Reflection phase of scattering electrons in a single-channel atomic wire

A theoretical study of the phase property of the reflection coefficient of a single-channel quantum system is presented. This reflection phase information is required for a complete characterization of the scattering problem in the system. It is found that the phase of the reflection coefficient of the system shifts abruptly by pi when the reflection probability passes through a zero. It is also f

CreditGrades and the iTraxx CDS index market

In the study reported, the CreditGrades model was used to calculate credit default swap spreads and the spreads were compared with empirically observed CDS spreads for eight iTraxx indices covering Europe. Theoretical and empirical spread changes were found to be significantly correlated. Also, lagged theoretical spread changes were correlated with current iTraxx spread changes. The correlations i

Lysine adducts between methyltetrahydrophthalic anhydride and collagen in guinea pig lung

The formation of adducts between methyltetrahydrophthalic anhydride (MTHPA), an important industrial chemical and potent allergen, and collagen from guinea pig lung tissue was investigated. Collagen peptides were obtained from the lung tissue by homogenization, defatting, washing, and digestion with collagenase. In experiments in vitro, lung tissue was exposed to 8.4 mumol (50 microCi) of 14C MTHP

Analysis of an Extremal Controller for Hammerstein Models

The ordinary differential equations given by Ljung(1977) are used to analyse the behaviour of a certain adaptive extremal controller. It is shown that this controller will usually converge to the wrong point.This work was supported by the Swedish Board for Technical Development under contract No. 76-3804.

Intraobserver reproducibility of Doppler measurements of uterine artery blood flow velocity in premenopausal women

OBJECTIVE: To determine the intraobserver repeatability of Doppler measurements of uterine artery blood flow velocity and the contribution of various factors to within-subject variance. DESIGN: Seventeen healthy premenopausal women underwent vaginal Doppler ultrasound examination of the uterine artery by the same observer. Three measurements were taken at each of three sites: 1) the currently reco

Durkheim och Mannheim som filosofisociologer

Kan sociologin användas till att förstå filosofiskt tänkande? De senaste decennierna har en ny typ av studie växt fram som studerar filosofiskt tänkande ur ett sociologiskt perspektiv. På engelska benämns denna desciplin sociology of philosophy respektive sociology of philosophical knowledge. En lämplig svensk översättning torde bli filosofisociologi. Filosofisociologisk forskning syftar till at

Prevention of progression to severe obesity in a group of obese schoolchildren treated with family therapy

STUDY OBJECTIVE. To evaluate the effect of family therapy on childhood obesity. DESIGN. Clinical trial. One year follow-up. SETTING. Referral from school after screening. PARTICIPANTS. Of 1774 children (aged 10 to 11), screened for obesity, 44 obese children were divided into two treatment groups. In an untreated control group of 50 obese children, screened in the same manner, body mass index (BMI

Robustness Analysis of Uncertain and Nonlinear Systems

Control design is often done based on simplified models. After design it is necessary to verify that the real closed loop system behaves well. This is mostly done by experiments and simulations. Theoretical analysis is an important complement to this that can help to verify critical cases. Structural information about uncertainties, time-variations, nonlinearities, and signals can be described by

The Cytotoxic and Genotoxic Effects of Conjugated Trans-2-Nonenal (T2N), an Off-Flavor Compound in Beer and Heat Processed food Arising from Lipid Oxidation

This study investigates the toxic effect of E(2)nonenal (trans-2-nonenal, T2N) and its conjugate with horse muscle myoglobin (Mb) tested on murine cell line L929 and human cell line A549, as well as the genotoxic effect of these compounds assayed by measuring of micronuclei in human cells K562. It is an aldehyde, which is occurring as the substance responsible for an off flavour in aged beers, but

Pain and fractures are independently related to lower walking speed and grip strength: Results from the population study "Good Ageing in Skåne".

Background Earlier reports on reduced physical performance and osteoporosis-related fractures have mostly been short-term studies. The aim of this investigation was to examine the effects of fractures on physical functioning 3 years after trauma, the latter being stratified for pain. Participants and methods The study consisted of a population-based case-control study including 289 subjects from t