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Energetics, cost reduction and functional consequences of fish morphology

Cost reduction strategies are often invoked as explanations when studies of adaptation fail to find predicted costs. This might seem discouraging, offering little opportunity for further investigation. In this paper, we demonstrate that cost reduction strategies can themselves be investigated by arguments from design. Recent work on inducible morphological defences has shown that hydrodynamical di

Severnaya Zemlya, Arctic Russia: a nucleation area for Kara Sea ice sheets during the Middle to Late Quaternary

Quaternary glacial stratigraphy and relative sea-level changes reveal at least four expansions of the Kara Sea ice sheet over the Severnaya Zemlya Archipelago at 79 degrees N in the Russian Arctic, as indicated from tills interbedded with marine sediments, exposed in stratigraphic superposition, and from raised-beach sequences that occur at altitudes up to 140 m a.s.l. Chronologic control is provi

Higher smoking prevalence in urban compared to non-urban areas: Time trends in six, European countries

We investigated differences in smoking prevalence between urban and non-urban area of residence in six Western European countries (Sweden, Finland, Denmark, Germany, Italy and Spain), and smoking prevalence trends over the period 1985-2000. In most countries, smoking prevalence was highest in urban areas, and increased with urbanization. Urban/non-urban inequalities were most pronounced among indi

Estimating carbon emissions from African wildfires

We developed a technique for studying seasonal and interannual variation in pyrogenic carbon emissions from Africa using a modelling approach that scales burned area estimates from L3JRC, a map recently generated from remote sensing of burn scars instead of active fires. Carbon fluxes were calculated by the novel fire model SPITFIRE embedded within the dynamic vegetation model framework LPJ-GUESS,

Recombinant antibodies to an oxidized low-density lipoprotein epitope induce rapid regression of atherosclerosis in apobec-1(-/-)/low-density lipoprotein receptor(-/-) mice.

OBJECTIVES: The present study tested the hypothesis that treatment with human recombinant immunoglobulin G1 (IgG1) antibodies against a specific oxidized low-density lipoprotein (oxLDL) epitope will induce regression of existing atherosclerotic lesions in LDL receptor-deficient mice expressing apolipoprotein B-100 (apoB-100) (Apobec-1(-/-)/LDLR(-/-)). BACKGROUND: Oxidized LDL plays an essential ro

Sick Leave Before and After Diagnosis of Rheumatoid Arthritis - A Report from the Swedish TIRA Project

Objective. Our study describes sick leave during 3 years before and 3 years after diagnosis of rheumatoid arthritis (RA) in relation to referents and identifies predictors for sick leave during the third year after diagnosis of RA. Methods. One hundred twenty patients (76% women) from the Swedish early RA study TIRA were included. Disease activity and disability were registered regularly during 3

Patterns of morphometric variation and a new supraspecific classification of apomictic taxa of Hieracium (Asteraceae) from Denmark and southern Sweden

Patterns of variation among all micro-species of Hieracium sect. Hieracium and H. sect. Vulgata known from Denmark and southern Sweden are investigated. Forty-three, possibly independent morphological characters are used. Significant correlations were revealed among the majority of the characters. Multivariate analyses did not reveal any discontinuities in the variation or any discrete groups of s

Effect of a matrix metalloproteinase activity and TNF-alpha converting enzyme inhibitor on intra-abdominal adhesions.

BACKGROUND: Formation of intra-abdominal adhesions depends, in part, on the activity of serine proteinases. Matrix metalloproteinases (MMP) are required for epithelialization of skin wounds but their involvement in mesothelialization of peritoneal wounds and in adhesion pathogenesis is not known. Early tumor necrosis factor-alpha (TNF-alpha) levels have been proposed to reflect propensity to adhes

Rapid and reproducible infectivity end-point titration of virulent phage in a microplate system

The standard method for measuring the it umber of infectious phages in solution has traditionally been the plaque forming assay. An alternative method is described where the number of lytic, infectious phages is determined in an endpoint titration assay adapted for a microplate system. In this model system, susceptible Escherichia coli 136 at a density of 4 x 10(7) cells/ml, were mixed with an equ

Hypoxic/ischaemic cell damage in cultured human NT-2 neurons

Postmitotic neurons were generated from the human NT-2 teratocarcinoma cell line in a novel rapid differentiation procedure. These neurons were used to establish an in vitro assay system that allows the investigation of hypoxic/ischaemic cell damage and the development of neuroprotective strategies. In experiments of simulated ischaemia, the neurons were subjected to anoxia and hypoglycaemia. The

Air pollutants and tear film stability--a method for experimental evaluation

Instability of the pre-ocular tear film causes symptoms of dry eyes. Tear film instability may be caused by exposure to air pollutants, but identification of causative agents is often difficult. We describe an in vitro technique for assessment of putative agents on the surface activity of Meibomian lipids. The lipids were obtained from bovine eyelids and dissolved in chloroform. Surface activity o

Leukotriene A(4) hydrolase - Identification of a common carboxylate recognition site for the epoxide hydrolase and aminopeptidase substrates

Leukotriene ( LT) A(4) hydrolase is a bifunctional zinc metalloenzyme, which converts LTA(4) into the neutrophil chemoattractant LTB4 and also exhibits an anion-dependent aminopeptidase activity. In the x-ray crystal structure of LTA(4) hydrolase, Arg(563) and Lys(565) are found at the entrance of the active center. Here we report that replacement of Arg(563), but not Lys(565), leads to complete a

The human footprint in the carbon cycle of temperate and boreal forests

Temperate and boreal forests in the Northern Hemisphere cover an area of about 2 times 107 square kilometres and act as a substantial carbon sink (0.6–0.7 petagrams of carbon per year)1. Although forest expansion following agricultural abandonment is certainly responsible for an important fraction of this carbon sink activity, the additional effects on the carbon balance of established forests of

High carrier mobility in low band gap polymer-based field-effect transistors

A conjugated polymer with a low band gap of 1.21 eV, i.e., absorbing infrared light, is demonstrated as active material in field-effect transistors (FETs). The material consists of alternating fluorene units and low band gap segments with electron donor-acceptor-donor units composed of two electron-donating thiophene rings attached on both sides of a thiadiazolo-quinoxaline electron-acceptor group

Modulation of the reactivity, stability and substrate- and enantioselectivity of an epoxidation catalyst by noncovalent dynamic attachment of a receptor functionality - aspects on the mechanism of the Jacobsen-Katsuki epoxidation applied to a supramolecular system

The synthesis of the components of the dynamic supramolecular hydrogen-bonded catalytic system 2 + 3 is described. The catalytic performance and substrate- and enantioselectivity of Mn(salen) catalyst 2 were investigated in the presence and absence of the Zn(porphyrin) receptor unit 3. The effects of pyridine and pyridine N-oxide donor ligands were also studied. Some aspects on the mechanism of th

Comparative genomic hybridization of postirradiation sarcomas

BACKGROUND. Radiotherapy is a known risk factor for sarcoma development. Postirradiation sarcomas arise within the radiation field after a latency period of several years and usually are highly malignant. Very little is yet known about their genetic changes. METHODS. Twenty-seven postirradiation sarcomas were analyzed by comparative genomic hybridization, which allows genome-wide screening of DNA

PID control design and $H_infty$ loop shaping

This paper shows that traditional methods for design of PID controllers can be related to robust H= control. In particular, it shows how the specifications in terms of maximum sensitivity and maximum complementary sensitivity are related to the weighted H= norm introduced by Glover and McFarlane [5]. The paper also shows how to use the Vinnicombe metric to classify those classes of systems which c