This thesis studies the computational complexity and polynomial-time approximability of a number of discrete combinatorial optimization problems involving labeled trees and strings. The problems considered have applications to computational molecular biology, pattern matching, and many other areas of computer science. The thesis is divided into three parts. In the first part, we study some proble

Intestinal alk-SMase (alkaline sphingomyelinase) is an ectoenzyme related to the NPP (nucleotide phosphodiesterase) family. It has five potential N-glycosylation sites and predicated transmembrane domains at both the N- and C-termini. The amino acid residues forming the two metal-binding sites in NPP are conserved, and those of the active core are modified. We examined the functional changes of th

Sorption may affect the bioavailability and biodegradation of pesticides in soils. The aim of this study was to test the effect of surface sorption on microbial utilization of the herbicide glyphosate as a source of phosphorus, nitrogen, or carbon. We added goethite to a humus soil to manipulate the soil's glyphosate sorption capacity. The addition of glyphosate generally either decreased microbia

Streptococcus pyogenes, an important human pathogen, expresses several proteins that interact with the immune system of the host. Among the proteins isolated from different bacterial strains are antiphagocytic M proteins, Ig Fc-binding proteins and exotoxins that act as superantigens. Here we report a novel interaction between S. pyogenes and the human immune system, the ability of most S. pyogene

Background: BARD1 was originally identified as a BRCA1- interacting protein but has also been described in tumour-suppressive functions independent of BRCA1. Several studies have indicated that the BARD1 gene is a potential target for germline changes predisposing to breast and ovarian cancer. The C- terminal Cys557Ser change has previously been uncovered to associate with an increased risk of bre

This article deals with how Swedish welfare authorities, governmental as well as municipal, performed personal case studies during the period 1940 to 1970. The visits at home are focused, as a mean of the authorities to generate truth of the inquired woman. The home visit was part of a personal case inquiry, perhaps initiated from the authorities to create basic data for decision-making. The examp

The L1 protuberance of the 50S ribosomal subunit is implicated in the release/disposal of deacylated tRNA from the E site. The apparent mobility of this ribosomal region has thus far prevented an accurate determination of its three-dimensional structure within either the 50S subunit or the 70S ribosome. Here we report the crystal structure at 2.65 Å resolution of ribosomal protein L1 from Sulfolob

Popular Abstract in Swedish I forskningsarbetet som presenteras i denna avhandling har säkerhetskulturen studerats inom sjö- och flygtransportbranscherna med fokus på individers attityder och uppfattningar om säkerhetskulturen. En säkerhetskultur avspeglar de attityder, uppfattningar och värderingar som individer i en organisation delar när det gäller säkerheten. Säkerhetskulturen identifieras oftThe research presented in this thesis investigates sea and aviation transport safety culture, with a focus on perceptions and attitudes. A safety culture reflects the attitudes, beliefs, perceptions, and values that individuals share in relation to safety. Safety culture is often identified as being essential to an organization's ability to manage safety-related aspects of its operations. The aims

The report contains abstracts of Master Theses (examensarbeten) made at the Department of Automatic Control, Lund, during the academic year 81/82. During this year 30 theses were made by 40 students. Most of the theses are written in Swedish with an English abstract.

Smooth muscle strips from guinea pig ileum were cultured for 5 days and then tested for contractile properties to investigate whether endogenous polyamines influence excitation-contraction coupling. Inhibition of spermidine and spermine synthesis by culture in the presence of the adenosylmethionine decarboxylase (EC4.1.1.50) inhibitor CGP-48664 (1-10 microM) decreased spermidine and spermine level

Popular Abstract in Swedish Det är känt att låg socioekonomisk position (t.ex., låg inkomst, kort utbildning) och civilstånd, (t.ex., ensamstående) kan försämra hälsan. Den sämre hälsan medför ett ökat sjukvårdsbehov, och i ett jämlikt samhälle borde därför sjukvårdsutnyttjandet vara större bland de med låg socioekonomisk position och bland de som är ensamstående. Av samma anledning bör en högre fBesides individual characteristics, people born in the same country may present a related pattern of health status and health care utilisation, perhaps because they share a number of socioeconomic and cultural characteristics in addition to their common geographic origin and language. Rather than using simple ethnical or geographical categories, we apply multilevel regression analysis with individ

The effects of 2,3-butanedione monoxime (BDM) were studied in smooth muscle fibres from guinea pig taenia coli. In intact muscle, active force during contractions induced by high-K+ was inhibited by about 10% in 1 mM BDM and by approximately 70% in 10 mM BDM. Intracellular [Ca2+] during contraction, measured with the fura-2 technique, was reduced in the presence of BDM. The reduction in force and

We consider possible schemes for the resonance-enhanced two-photon ionization (RETPI) of Ne and Ar atoms under the action of bichromatic radiation of intense resonance lines of HI, HeI, and HeII in a radiation-rich astrophysical plasma. The ionization rate is comparable to or exceeds the recombination rate in rarified astrophysical plasma, which leads to the accumulation of singly ionized ions wit