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In situ detection of soot nanoparticles by time-resolved fluorescence analysis
We present a new implementation of the time-resolved fluorescence anisotropy technique for the analysis of carbon nanoparticles directly in a Bunsen-type propane flame. By exploiting femtosecond laser excitation, UV-visible laser-induced fluorescence and time resolution of the experimental set-up, small soot nanoparticles have been identified within the flame. From the measurement of the decay tim
Smoking and Risk for Amyotrophic Lateral Sclerosis: Analysis of the EPIC Cohort
Objective: Cigarette smoking has been reported as "probable" risk factor for Amyotrophic Lateral Sclerosis (ALS), a poorly understood disease in terms of aetiology. The extensive longitudinal data of the European Prospective Investigation into Cancer and Nutrition (EPIC) were used to evaluate age-specific mortality rates from ALS and the role of cigarette smoking on the risk of dying from ALS. Met
Theoretical study of electronic structure of silicon nanocrystals
We report on a theoretical study of the electronic structure of silicon nanocrystals with a shape of the regular rhombic dodecahedron, based on a tight-binding method. The energies of the lowest unoccupied state and the highest occupied state have been calculated. We have shown that the six-fold degenerate conduction band minima of the bulk silicon crystal are split into a non-degenerate A(1) stat
A phylogenetic study of the Lecanora rupicola group (Lecanoraceae, Ascomycota)
A molecular phylogeny of the Lecanora rupicola group is presented, based on ITS sequence analyses. The study includes saxicolous and corticolous members of the Lecanora rupicola group as well as other Lecanora species with pruinose apothecia. A phylogenetic hypothesis for species in Lecanora s. lat. and various other genera in Lecanoraceae, based on an alignment-free distance estimation technique,
Higher Early Mortality with Simultaneous Rather than Staged Bilateral TKAs Results From the Swedish Knee Arthroplasty Register
Patients with knee osteoarthritis (OA) often present with symptoms that warrant bilateral TKAs. There are potential benefits to operating on both knees on the same day, but the safety of simultaneous bilateral TKAs has been questioned. To evaluate whether there were any differences in 30-day mortality between patients having simultaneous bilateral TKAs and those having staged bilateral TKAs, we an
Structure of microemulsion - ABA triblock copolymer networks
Structural equilibrium properties of transient networks formed by microemulsion droplets and ABA triblock copolymers in solution have been studied by Monte Carlo simulation. The droplets were represented by soft spheres, and the polymers were represented by junctions connected by harmonic bonds with an angular potential regulating the intrinsic chain stiffness. The interaction parameters were sele
Towards European climate risk surfaces: the extent and distribution of analogous and non-analogous climates 1931-2100
Aim Climate is an important determinant of species distributions. We assess different aspects of risk arising from future climate change by quantifying changes in the spatial distribution of future climatic conditions compared with the recent past. Location Europe. Methods A 10' x 10' resolution gridded data set of five climate variables was used to calculate expected changes to the area, distance
Sex pheromone mimicry in the early spider orchid (Ophrys sphegodes): patterns of hydrocarbons as the key mechanism for pollination by sexual deception
Abstract We investigated the female-produced sex pheromone of the solitary bee Andrena nigroaenea and compared it with floral scent of the sexually deceptive orchid Ophrys sphegodes which is pollinated by Andrena nigroaenea males. We identified physiologically and behaviorally active compounds by gas chromatography with electroantennographic detection, gas chromatography-mass spectrometry, and beh
Large eddy simulation and experimental studies of a confined turbulent swirling flow
Laser Doppler velocimetry (LDV) measurement and large eddy simulation (LES) were used to study confined isothermal turbulent swirling flows in a model dump combustor. The aim was to gain deeper understanding of the flow and turbulence structures in dump combustors and to examine the capability of LES for prediction of turbulent swirling flows. A refractive index matching technique is used in the L
Comparison of PMMA and SU-8 resist moulds for embossing of PZT to produce high-aspect-ratio microstructures using LIGA process
In this paper results are presented from a range of experiments to explore the feasibility of inserting a ceramic material PZT (lead zirconium titanate) into different kinds of high-aspect-ratio resist moulds. Polymethylmethacrylate (PMMA) and SU-8 on silicon substrates and free-standing SU-8 membranes with microcavities or through-holes (defined by X-ray lithography) have been used as moulding me
Site-Selective Participator Decay of Core-Excited Butadiene
The decay of core-excited electronic states in free 1,3 trans butadiene molecules has been studied using high-resolution synchrotron radiation and electron spectrometry. The core-level energy shift between the terminal and central carbon atoms is 0.64 eV making selective excitation of core electrons from these atoms possible. Resonant excitation to the au(*) valence state leads to autoionizing dec
Compatibilizing effects of poly(styrene-graft-ethylene oxide) in blends of polystyrene and butyl acrylate polymers
The compatibilizing effect of poly(styrene-graft-ethylene oxide) in polystyrene (PS) blends with poly(n-butyl acrylate) (PBA) and poly(n-butyl acrylate-co-acrylic acid) (PBAAA) was investigated. No significant effects of the graft copolymer on the domain size were found in the PBA blends. By functionalizing PBA with acrylic acid, the average size of the polyacrylate domains was reduced considerabl
Conceptual and perceptual memory: Retrieval orientations reflected in event-related potentials
In memory retrieval, search can be guided by mental sets towards different subsets of the available evidence. Such retrieval orientations have been suggested to leave an imprint on event-related potentials (ERPs). The present study aimed at characterizing orientations towards perceptual and conceptual evidence in a recognition task, where pictures and words were studied. In the recognition test, i
Asymmetric contests over resources for survival and migration: a field experiment with bluethroats
The relative importance of prior occupancy and of asymmetries in both value of winning and in resource-holding potential for the outcome of animal contests was tested. Bluethroats, Luscinia s. svecica, were offered food ad libitum in the field. Prior to migration, at a moulting site, their weight increased rapidly and peaked after a few days. Lean birds won significantly more interactions than fat
Review of 《漠南情: 內蒙古生产建设兵团写真》
Endothelium-dependent relaxation in pulmonary arteries after lung preservation and transplantation
Pulmonary hypertension is frequently seen after lung transplantation. To study how the release of the endothelium-dependent relaxing factor is affected by lung preservation and transplantation, porcine pulmonary arteries were investigated in organ baths. The arteries (1 mm in diameter) were taken from fresh nonperfused lungs (group I), lungs immediately after flush-perfusion with a low-potassium-d
Family relations, family climate and sexual abuse
In Europe, 10-20% of all women and 3-10% of all men have experienced sexual abuse before the age of 18, according to surveys. Psychosocial problems are often seen as both short- and long-term consequences of such abuse. Family dysfunction may be seen as both a risk factor for abuse and a result of the disclosure of abuse. The aim of this research was to study how adolescents and adults, sexually a
Persistent activation of microglia is associated with neuronal dysfunction of callosal projecting pathways and multiple sclerosis-like lesions in relapsing--remitting experimental autoimmune encephalomyelitis
Cortical pathology, callosal atrophy and axonal loss are substrates of progression in multiple sclerosis (MS). Here we describe cortical, periventricular subcortical lesions and callosal demyelination in relapsing-remitting experimental autoimmune encephalomyelitis in SJL mice that are similar to lesions found in MS. Unlike the T-cell infiltrates that peak during acute disease, we found that micro