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Spectroscopic units in conjugated polymers: A quantum chemically founded concept?

In conjugated polymers the concept of spectroscopic units belonging to different spatial segments of the chain, which are responsible for the spectroscopic properties of the polymer, has been used to explain the spectral heterogeneity and the excitation migration by (Forster type) hopping transfer. In the present work we study the possible mechanism of segmentation of polythiophene into spectrosco

Development and testing of a frequency-agile optical parametric oscillator system for differential absorption lidar

An all-solid-state fast-tuning lidar transmitter for range- and temporally resolved atmospheric gas concentration measurements has been developed and thoroughly tested. The instrument is based on a commercial optical parametric oscillator (OPO) laser system, which has been redesigned with piezoelectric transducers mounted on the wavelength-tuning mirror and on the crystal angle tuning element in t

Wind-dependent foraging flight in the Osprey Pandion haliaetus

We studied the foraging technique of Ospreys Pandion haliaetus during different wind speed conditions at Lake Hammarsjon, Sweden in autumn 2003. Different fishing techniques were used with a shift in relation to wind speed: (1) without hovering, (2) hovering with pure flapping flight, (3) hovering with flapping flight and gliding into the wind, and (4) hovering with pure gliding. The results suppo

Study of the reactivity and in vitro bioactivity of Sr-substituted alpha-TCP cements

In this study the effect of strontium substitution on the hydrolysis of alpha-tricalcium phosphate (alpha-TCP) toward the formation of calcium deficient hydroxyapatite (CDHA) was investigated. For that purpose substituted alpha-TCP powders with 1, 5 and 10 mol% Sr substitution for Ca were synthesized by reacting at 1500 degrees C stoichiometric amounts of CaCO3, SrCO3, and Ca2P2O7, followed by rap

Plantago lanceolata L. and Rumex acetosella L. differ in their utilisation of soil phosphorus fractions

To establish relationships between soil phosphorus (P) fractions and leaf P, a mycorrhizal species (Plantago lanceolata L.) was compared with a typically non-mycorrhizal species (Rumex acetosella L.) in a glasshouse experiment. The plants were grown in 40 soils from non-fertilised, abandoned pastures or abandoned arable fields and leaf P concentration were found to be related to various soil P fra

Charge and energy transfer in binaphthalene molecule with two spiropyran units used for chiral molecular switches and logic gates

A new binaphthalene molecule with two spiropyran units used for chiral molecular switches and logic gates was synthesized and chaxacterized.(12) In this paper, charge and energy transfer in binaphthalene molecule with two spiropyran units are theoretically investigated with quantum chemistry method, as well as 2D and 3D real space analysis methods, since molecule construction with photoinduced ele

Emotion and social motivation in university students´ real life moral dilemmas

Studied the relationship between motivation and approaches to moral decision-making, and the emotions experienced in moral dilemmas. 44 students were interviewed about a dilemma they had faced. Intimacy was related to a preference for making decisions after having consulted others and to being open to their values and norms, whereas achievement was related to consequence-oriented reasoning and con

Measurement of protein diffusion through poly(D,L-lactide-co-glycolide)

A novel method was developed for studying the diffusion of proteins through poly(D,L-lactide-co-glycolide) (PLG), using a diffusion cell. To develop improved formulations for the controlled release of encapsulated drugs it is important to understand the underlying release mechanisms. When using low-molecular-weight PLG as the release-controlling polymer, diffusion through the pores is often propos

Colour development in copper ruby alkali silicate glasses. Part 1. The impact of tin(II) oxide, time and temperature

The development of the red colour in copper ruby alkali silicate glasses has been studied by means of ultraviolet/visible spectroscopy, TEM and EXAFS. The results show that in both red and slightly overstruck, brownish glasses the colour is due to clusters of metallic copper. Before striking non-coloured glasses contain mainly cuprous ions, Cu+. Tin acts as a reducing agent but also has an acceler

Neuron-mediated generation of regulatory T cells from encephalitogenic T cells suppresses EAE.

Neurons have been neglected as cells with a major immune-regulatory function because they do not express major histocompatibility complex class II. Our data show that neurons are highly immune regulatory, having a crucial role in governing T-cell response and central nervous system (CNS) inflammation. Neurons induce the proliferation of activated CD4+ T cells through B7-CD28 and transforming growt

Effects of polyamines on voltage-activated calcium channels in guinea-pig intestinal smooth muscle

Effects of polyamines on the spontaneous mechanical and electrical activity of guinea-pig intestinal smooth muscle were studied. Spermine and spermidine inhibited action potential generation and contractions, while putrescine had no effect. Single smooth muscle cells were isolated from the longitudinal muscle layer of the guinea-pig ileum. Whole-cell voltage-clamp experiments were carried out to i

Thermal versus mechanical unfolding of ubiquitin

The authors studied the temperature-induced unfolding of ubiquitin by all-atom Monte Carlo simulations. The unfolding behavior is compared with that seen in previous simulations of the mechanical unfolding of this protein, based on the same model. In mechanical unfolding, secondary-structure elements were found to break in a quite well-defined order. In thermal unfolding, the authors saw somewhat