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Self-healing and self-organized gold nanoparticle films at a water/organic solvent interface

Gold nanoparticles (5 nm and 20 nm) have been synthesized and stabilized with mercaptoundecanol. These particles, although insoluble in water or common organic solvents, spread as a thin film at the liquid-liquid interface between a water phase and an organic phase. Films of these gold nanoparticles have been observed both by conventional transmission electron microscopy of deposited samples and b

Allozyme and chloroplast DNA variation in island and mainland populations of the rare Spanish endemic, Silene hifacensis (Caryophyllaceae)

Silene hifacensis is a narrowly endemic plant, restricted to a few small populations on limestone cliffs in the Spanish province of Alicante and on the Balearic island of Ibiza. The species was collected to extinction in its original mainland location by the early 20th century. Attempts have been made to reintroduce S. hifacensis to this area but conservation efforts are limited by a lack of infor

The effect of polymers on the phase behavior of balanced microemulsions: diblock-copolymer and comb-polymers

The effect of some amphipilic diblock-copolymers and comb-polymers on a balanced Winsor III microemulsion system is investigated with the quaternary system n-octyl-beta-D-glucoside/1-octanol/n-octane/D2O as basis system. The diblock-copolymers are polyethyleneoxide-co-polydodecenoxide (PEOx PEDODOy ) and polyethyleneoxide-co-polybutyleneoxide (PEO (x) PEBU (y) ), constituted of a straight chain hy

Frequency measures obtained from the surface electrocardiogram in atrial fibrillation research and clinical decision-making

Frequency Measures in AF. Introduction: Frequency analysis of fibrillation (FAF) and time-frequency analysis (TFA) were developed recently in order to quantify atrial electrical remodeling in atrial fibrillation (AF) from the surface ECG. This article describes the experience with these two different frequency analysis techniques in consecutive AF patients and discusses possible applications in AF

Trust in surveys and games - A methodological contribution on the influence of money and location

This paper explores methods to study trust. In a variety of settings, answers to survey questions and choices in a trust game are obtained from student sample pools. Some subjects are approached by mail and execute their task at home whereas others participate in classroom experiments. No differences between the results obtained by these methods are observed. Furthermore, one additional group play

Experimentally induced effects of heavy metal on microbial activity and community structure of forest mor layers

This study compared the toxic effects of adding chromium (Cr), zinc (Zn), lead (Pb), molybdenum (Mo), nickel (Ni), and cadmium (Cd) at three dose levels to mor layer samples in laboratory experiments. Microbial activity in the form of soil respiration was monitored for 64 days. At the end of the experimental period, the composition of the soil microbial community structure was analysed by phosphol

Pupil shapes and lens optics in the eyes of terrestrial vertebrates

Animal eyes that are primarily used under low-light conditions usually have optical systems of short depth of focus, such that chromatic defocus may lead to considerable blurring of the images. In some vertebrates, the problem is solved by multifocal lenses having concentric zones of different focal lengths, each of which focuses a different relevant spectral range onto the retina. A partially con

A virtual linear accelerator for verification of treatment planning systems

A virtual linear accelerator is implemented into a commercial pencil-beam-based treatment planning system (TPS) with the purpose of investigating the possibility of verifying the system using a Monte Carlo method. The characterization set for the TPS includes depth doses, profiles and output factors, which is generated by Monte Carlo simulations. The advantage of this method over conventional meas

From bench to bed: the potential of stem cells for the treatment of Parkinson's disease

Parkinson's disease (PD) is the most common movement disorder. The neuropathology is characterized by the loss of dopamine neurons in the substantia nigra pars compacta. Transplants of fetal/embryonic midbrain tissue have exhibited some beneficial clinical effects in open-label trials. Neural grafting has, however, not become a standard treatment for several reasons. First, the supply of donor cel

Base deficit estimation in umbilical cord blood is influenced by gestational age, choice of fetal fluid compartment, and algorithm for calculation.

Objective: The purpose of this study was to explore the influences of gestational age, the choice of fetal fluid compartment, and the algorithm for calculation on the estimation of the base deficit in umbilical cord arterial blood Lit birth. Study design: From 1995 to 2002, cord arterial blood gases and obstetric data were available for 43,551 newborn infants at 37 + weeks of gestation (cohort 1).

High levels of genetic variation in the haploid leafy liverwort Porella platyphylla from the southeastern United States

The few studies that have investigated levels of genetic variation in liverworts have found very little polymorphism. Our electrophoretic data show, however, that the leafy liverwort Porella platyphylla maintains high levels of genetic variation in at least some natural populations from the southeastern United States. Within a single population from southwestern North Carolina, we detected 26 dist

Determinants of woody cover in African savannas

Savannas are globally important ecosystems of great significance to human economies. In these biomes, which are characterized by the co-dominance of trees and grasses, woody cover is a chief determinant of ecosystem properties(1-3). The availability of resources ( water, nutrients) and disturbance regimes ( fire, herbivory) are thought to be important in regulating woody cover(1,2,4,5), but percep

The long-term stability of temperament traits measured after a suicide attempt. A 5-year follow-up of ratings of Karolinska Scales of Personality (KSP)

The main aim of the present study was to investigate whether or not temperament dimensions are stable over time. Twenty-six patients (21 women and five men) filled in the Karolinska Scales of Personality (KSP) both at admission after a suicide attempt (index) and at follow-up 5 years later. KSP changes were significantly associated with low severity of psychiatric symptoms and no reported reattemp

Civil Aircraft for the regular investigation of the atmosphere based on an instrumented container: The new CARIBIC system

An airfreight container with automated instruments for measurement of atmospheric gases and trace compounds was operated on a monthly basis onboard a Boeing 767-300 ER of LTU International Airways during long-distance flights from 1997 to 2002 (CARIBIC, Civil Aircraft for Regular Investigation of the Atmosphere Based on an Instrument Container, http://www.caribic-atmospheric.com). Subsequently a m

Water uptake and release from iodine-containing bone cement.

Water uptake and release characteristics of PMMA cement containing the water-soluble contrast media iohexol or iodixanol have been investigated. The water uptake study revealed that iohexol had the highest uptake of water (3.7%) and that iodixanol had an uptake close to that of Palacos(R) R (2.3% and 1.9%). The curves obtained showed the materials to follow classic diffusion theory, with an initia