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Variable Be-10 fluxes in lacustrine sediments from Tristan da Cunha, South Atlantic: a solar record?

A 650-yr-long sediment sequence from a crater lake on Tristan da Cunha, South Atlantic, was analysed for its Be-10 content. Based on C-14 dating, and sedimentary, geochemical, magnetic and palynological records, the period between 900 and 1450 AD appears to have been unusually stable in terms of sedimentation and vegetation and therefore this period was chosen for analysis of the Be-10 content. Du

2MOLCAS as a development platform for quantum chemistry software

This work presents the quantum chemistry package MOLCAS, with emphasis on its usefulness as a platform for developing new quantum chemical codes, and the reader is assumed to be familiar with such a process. The development of new codes for quantum chemistry is a time-consuming job that can be dramatically simplified by using libraries for standard problems (such as calculation of integrals), and

Tipping the balance of deterministic lateral displacement devices using dielectrophoresis.

We report the use of dielectrophoresis (DEP) to achieve tunability, improve dynamic range and open up for the separation of particles with regard to parameters other than hydrodynamic size in deterministic lateral displacement (DLD) devices. DLD devices have been shown capable of rapidly and continuously separating micrometer sized plastic spheres by size with a resolution of 20 nm in diameter and

Effects of wind and weather on red admiral, Vanessa atalanta, migration at a coastal site in southern Sweden

Each autumn, large numbers of red admirals migrate throughout northern Europe,flying south, to reach areas with conditions suitable for surviving the winter. We observed the visible butterfly migration at Falsterbo peninsula, the southwesternmost point in Sweden, where red admirals are seen most autumns. ying towards the Danish coast on their way to more southern parts of Europe. Weather parameter

Barriers and distances as determinants for the evolution of bird migration links: the arctic shorebird system

We analysed migratory connectivity between different winter quarters and breeding sectors in the circumpolar tundra region for arctic shorebirds, in relation to migratory distances and ecological barriers. Total distances and barriers were calculated and measured for all potential migratory orthodrome links between 10 selected winter regions and 12 breeding sectors. The migratory segment between t

Dynamic light scattering and fluorescence study of the interaction between double-stranded DNA and poly(amido amine) dendrimers

The interaction between a cationic poly(amido amine) (PAMAM) dendrimer of generation 4 and double-stranded salmon sperm DNA in 10 mM NaBr solution has been investigated using dynamic light scattering (DLS) and steady-state fluorescence spectroscopy. The structural parameters of the formed aggregates as well as the complex formation process were studied in dilute solutions. When DNA is mixed with P

The rotating pole test: evaluation of its effectiveness in assessing functional motor deficits following experimental head injury in the rat

Neurological motor dysfunction is often an integral component of the neurological sequelae of traumatic brain injury (TBI). In experimental TBI, neurological motor testing is an outcome measure used to monitor severity of injury, and the response to treatment. This study evaluates the effectiveness and sensitivity of the rotating pole test (RP) to characterize and evaluate the temporal course of m

A shoreline to deep basin correlation chart for the middle Silurian coupled extinction-stable isotopic event

A shoreline to deep basin correlation chart for the middle Silurian coupled extinction-stable isotopic event is presented. The chart is a first attempt to synthesise new stratigraphic, faunal and stable isotopic data, as well as diversity changes among organic-walled microplankton (acritarchs), from the Grotlingbo-1 and Hunninge-1 cores on Gotland (Sweden), along with previously published data fro

The glutathione levels are reduced in Goto-Kakizaki rat retina, but are not influenced by aminoguanidine treatment

PURPOSE: To examine the levels of the free radical protecting enzyme glutathione and the endothelial/pericyte ratio in retinal capillaries in the Goto-Kakizaki (GK) Wistar rat, with and without aminoguanidine treatment. METHODS: Eight-month-old GK rats, with non-obese, spontaneous non-insulin-dependent diabetes mellitus (NIDDM), were examined after a six month period of aminoguanidine treatment. G

Sensing extracellular matrix: an update on discoidin domain receptor function

Discoidin Domain Receptors (DDRs) have recently emerged as non-integrin-type receptors for collagen. The two mammalian gene products Discoidin Domain Receptor 1 and -2 constitute a subfamily of tyrosine kinase receptors that are selectively expressed in a number of different cell types and organs. Upon collagen activation, DDRs regulate cell adhesion, proliferation and extracellular matrix remodel

Fitness consequences of floral variation in Senecio jacobaea (Asteraceae): evidence from a segregating hybrid population and a resource manipulation experiment

The present study examines some of the ecological factors that might exert selection on floral morphology in Senecio jacobaea, a self-sterile composite which exhibits geographic variation in the frequency of rayed and discoid individuals. Regression analyses of phenotypic data from a large, segregating hybrid population, established in a semi-natural (garden) environment and studied over a 2-year

The influence of food quality and availability on trophic position, carbon signature, and growth rate of an omnivorous crayfish

Fourteen sites in 13 streams were surveyed to address the importance of food quality and quantity on trophic position, carbon signature, and growth rate of noble crayfish (Astacus astacus) by combining the analyses of gut content, stable isotopes, and RNA-DNA ratio. The gut content analysis showed an omnivorous feeding habit, but total animal food sources contributed more to the nitrogen and carbo

The use of reference image criteria in X-ray diagnostics: an application for the optimisation of lumbar spine radiographs.

Abstract in Undetermined To ensure that sufficient image quality is obtained in diagnostic radiology, the image quality of clinical radiographs has to be evaluated. We present two methods herein for evaluating antero-posterior (AP) radiographs of the lumbar spine. One was using image criteria, including six anatomical details (absolute method). In the other, the visibility of anatomical details re

Effect of rheumatoid arthritis on work status and social and leisure time activities in patients followed 8 years from onset

OBJECTIVE: To evaluate the development of handicap in patients with rheumatoid arthritis (RA) followed 8 years from onset. METHODS: The study group consisted of 106 patients participating in a prospective early RA study. The mean duration of joint symptoms at inclusion was one year. The patients were assessed at least once annually. Disability was measured with the Health Assessment Questionnaire

A system for monitoring cutting tool spontaneous failure based on the cutting edge stress estimation

Cutting tool spontaneous failure such as, edge fracture and chipping are common phenomena in the metal cutting process, especially when difficult workpiece materials which have poor cutibility are met in the machining process. The tool failures are often caused by high mechanical and thermal stresses acting in it. Monitoring stresses acting in a cutting edge during machining process can provide mo

Internal DNA pressure modifies stability of WT phage

dsDNA in bacteriophages is highly stressed and exerts internal pressures of many atmospheres (1 atm = 101.3 kPa) on the capsid walls. We investigate the correlation between packaged DNA length in A phage (78-100% of WT DNA) and capsid strength by using an atomic force microscope indentation technique. We show that phages with WT DNA are twice as strong as shorter genome mutants, which behave like

Cell water dynamics on multiple time scales

Water–biomolecule interactions have been extensively studied in dilute solutions, crystals, and rehydrated powders, but none of these model systems may capture the behavior of water in the highly organized intracellular milieu. Because of the experimental difficulty of selectively probing the structure and dynamics of water in intact cells, radically different views about the properties of cell wa

Energy conservation and saturation in small-x evolution

Important corrections to BFKL evolution are obtained from non-leading contributions and from non-linear effects due to unitarisation or saturation. It has been diffcult to estimate the relative importance of these effects, as NLO effects are most easily accounted for in momentum space while unitarisation and saturation are easier in transverse coordinate space. An essential component of the NLO co

Managing managerial identities: Organizational fragmentation, discourse and identity struggle

This is a case study of managerial identity work, based on an in-depth case of a senior manager and the organizational context in which she works. The article addresses the interplay between organizational discourses, role expectations, narrative self-identity and identity work Identity is conceptualized in processual terms as identity work and struggle. The article illuminates fragmentation as we