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In higher plants, genes for subunits of respiratory chain complex I (NADH:ubiquinone oxidoreductase) have so far been identified solely in organellar genomes. At least nine subunits are encoded by the mitochondrial DNA and 11 homologues by the plastid DNA. One of the 'key' components of complex I is the subunit binding the substrate NADH. The corresponding gene for the mitochondrial subunit has no

We studied the speciose butterfly genus Erebia by reconstructing its phylogenetic relationships using parsimony and Bayesian approaches. We estimated times and rates of diversification for its lineages and employed a biogeographical analysis in order to reconstruct its evolutionary history. DNA sequence data from one mitochondrial gene and three nuclear genes were analyzed for a total of 74 specie

An experimental study of the normalized three-jet rate of b quark events with respect to light quarks events (light = l equivalent to u, d, s) has been performed using the CAMBRIDGE and DURHAM jet algorithms. The data used were collected by the DELPHI experiment at LEP on the Z peak from 1994 to 2000. The results are found to agree with theoretical predictions treating mass corrections at next-to-

The endoplasmic reticulum (ER) structure is of central importance for the regulation of cellular anabolism, stress response, and signal transduction. Generally continuous, the ER can temporarily undergo dramatic structural rearrangements resulting in a fragmented appearance. In this study we assess the dynamic nature of ER fission in pyramidal neurons in organotypic hippocampal slice cultures stim

Most structured latex particles are formed in the nonequilibrium state as a result of the reaction kinetics proceeding faster than the phase separation kinetics. Of the many factors controlling such morphologies, the polarity and glass transition temperature (Tg) of the seed polymer are important. In order to study the direct effect of the seed polymer Tg on morphology, we produced a series of pol

Helicobacter pylori is the most important cause of gastritis, peptic ulcers and the development of gastric cancer. The chronic active inflammation is dominated by neutrophils, macrophages, lymphocytes and plasma cells. Several interleukins (IL-8, IL-10 and IFN-gamma) are involved in the inflammatory process in the gastric mucosa. The aim of this study was to investigate the gastric inflammation in

Isolated exposures of basalt in a 1000 km 2 area in the central northern part of Skane have long been known to the local people. A volcanic origin for these rocks was finally resolved by geologists during the early 1800s. Until 1965 the volcanic activity was considered to have occurred during the Cenozoic i.e. not older than 65 Ma. In the 1970s attempts were made to directly date the volcanic acti

Ad hoc networks, being able to organize themselves without user intervention, can easily provide their users with mobility, multimedia support and group communication. However, they have to combine quality of service (QoS) and multicast routing strategies. This article defines the resource management and admission control components of the ad hoc QoS multicast (AQM) routing protocol, which achieve

Hypoxia, a growing worldwide problem, has been intermittently present in the modern Baltic Sea since its formation ca. 8000 cal. yr BP. However, both the spatial extent and intensity of hypoxia have increased with anthropogenic eutrophication due to nutrient inputs. Physical processes, which control stratification and the renewal of oxygen in bottom waters, are important constraints on the formati

C3 and C5 convertases are central stages of the complement cascade since they converge the different initiation pathways, augment complement activation by an amplification loop and lead to a common terminal pathway resulting in the formation of the membrane attack complex. Several complement inhibitors attenuate convertase formation and/or accelerate dissociation of convertase complexes. Functiona

Sweden’s old-growth forests are disappearing due to the ever-increasing demand for timber. To protect them from logging, a specific articulation of environmental activism has gained momentum in recent years: biodiversity inventorying. Citizens (inventoryers) visit forests registered for logging to look for endangered species and turn their observation data into a powerful weapon of nature conserva

The deep recycling of surface material into Earth’s mantle is an integral process governing global water and fluid-mobile element cycles. This recycling is largely predicated on subduction operating efficiently, which may not apply for the first two billion years of Earth’s history. Tracing the initiation and evolution of the modern deep fluid-mobile element cycle requires determining when the man

The language of newspapers in the public sphere has a crucial impact on how the public perceives and participates in society. It can serve to encourage or counteract active and informed citizens; in fact, it is a crucial element in democratisation processes. The purposes of the present study are to elucidate what means of persuasion are used to support theses on politics in newspaper discourse dur

The topic of this article is experiences regarding Supplemental Instruction (SI) at two Scandinavian Universities. The purpose is to describe the basis for and implementation of SI programmes at the two universities, and to compare their similarities and differences. Our research questions were as follow: What were the reasons and background for implementing SI? How was the SI programme founded, p

Microbial stoichiometry has become a key aspect in ecological research as shifts in microbial C:N, C:P and N:P ratios upon nutrient addition are presumed to give insight into relative nutrient limitations for soil microorganisms–with far-reaching implications for biogeochemical processes. However, this expectation has never been tested against direct methods of microbial growth responses to nutrie

The European Spallation Source, currently under construction in Lund, Sweden, will be the world's most powerful neutron source. It is driven by a proton linac with a current of 62.5 mA, 2.86 ms long pulses at 14 Hz. The final section of its normal-conducting front-end consists of a 39 m long drift tube linac (DTL) divided into five tanks, designed to accelerate the proton beam from 3.6 MeV to 90 M

The core-multishell wurtzite structure (In,Ga)As–(Ga,Al)As–(Ga,Mn)As semiconductor nanowires have been successfully grown on GaAs(111)B substrates using MBE technique. The nanowires cores were grown with gold eutectic catalyser in vapour–liquid–solid growth mode. The double shell overgrowth, on the side facets of nanowires, was performed using lower substrate temperature (about 400 ◦C, and 230 ◦C,

In this article, the success of a risk communication programme conducted in two municipalities in Sweden is evaluated. The communication efforts were initiated in order to comply with the Seveso II Directive, passed as a national law in July 1999. Data from two different questionnaires are used. Between the distribution of the two questionnaires, an information campaign took place in the communiti

Translation is an essential genetic process for understanding the mechanism of gene expression. Due to the large number of protein sequences generated in the post-genomic era, conventional methods are unable to identify Translation Initiation Site (TIS) in human genes timely and accurately. It is thus highly desirable to develop an automatic and accurate computational model for identification of T

Free energy calculations play a crucial role in simulating chemical processes, enzymatic reactions, and drug design. However, assessing the reliability and convergence of these calculations remains a challenge. This study focuses on single-step free-energy calculations using thermodynamic perturbation. It explores how the sample distributions influence the estimated results and evaluates the relia