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Zero-phonon linewidth and phonon satellites in the optical absorption of nanowire-based quantum dots

The optical properties of quantum dots embedded in a catalytically grown semiconductor nanowire are studied theoretically. In comparison to dots in a bulk environment, the excitonic absorption is strongly modified by the one-dimensional character of the nanowire phonon spectrum. In addition to pronounced satellite peaks due to phonon-assisted absorption, we find a finite width of the zero-phonon l

Exciton diffusion and relaxation in methyl-substituted polyparaphenylene polymer films

Exciton diffusion in ladder-type methyl-substituted polyparaphenylene film and solution was investigated by means of femtosecond pump-probe spectroscopy using a combined approach, analyzing exciton-exciton annihilation, and transient absorption depolarization properties. We show that the different views on the exciton dynamics offered by anisotropy decay and annihilation are required in order to o

Increased visual dependence and otolith dysfunction with alcohol intoxication

dAlcohol intoxication affects the vestibular system and balance control in many ways. We have investigated how acute, moderate (blood alcohol concentrations of 0.06 +/- 0.01%), and high (0.10 +0.02%) alcohol intoxication affects the ability to perceive the visual horizontal and vertical and the visual field dependence measured with the rod and frame tests in 24 healthy participants. Alcohol ingest

Portal vein thrombosis: Prevalence, patient, characteristics and lifetime risk: A population study based on 23796 consecutive autopsies

AIM: To assess the lifetime cumulative incidence of portal venous thrombosis (PVT) in the general population. METHODS: Between 1970 and 1982, 23 796 autopsies, representing 84% of all in-hospital deaths in the Malmo city population, were performed, using a standardised protocol including examination of the portal vein. PVT patients were characterised and the PVT prevalence at autopsy, an expressio

Repulsion between oppositely charged macromolecules or particles

The interaction of two oppositely charged surfaces has been investigated using Monte Carlo simulations and approximate analytical methods. When immersed in an aqueous electrolyte containing only monovalent ions, two such surfaces will generally show an attraction at large and intermediate separations. However, if the electrolyte solution contains divalent or multivalent ions, then a repulsion can

Age-related trends in hip geometry in Sri Lankan women: a cross-sectional study

Indices of hip geometry are known to be predictive of hip fractures while sex and ethnic differences in hip geometry have been previously demonstrated. Age-related trends in hip geometry among Asians, however, have not been studied sufficiently. A total of 280 healthy, perimenopausal women, aged between 32 and 97 years, were selected from the Community Study Area of the Faculty of Medicine, Galle,

Profile of resonant photoelectron spectra versus the spectral function width and photon frequency detuning

The outermost, singly ionized valence state of N-2, the X (2)Sigma(g)(+) state, is investigated in detail as a function of the photon frequency bandwidth for core excitation to the N 1s-->pi(*) resonance, where the photon frequency is tuned in between the first two vibrational levels of this bound intermediate electronic state. We find a strong, nontrivial dependence of the resulting resonant phot

Within-plant variation in induced defence in developing leaves of cotton plants

According to optimal defence theory (ODT) plants should invest in stronger defence in the most valuable parts, such as reproductive or young tissue. Cotton plants are known to express high resistance to herbivore feeding in the developing leaves at the top of the plant after herbivore-damage. Cotton plants also have developing leaves on side shoots from the nodes all along the plant. This allowed

Long-term consequences of human alpha-synuclein overexpression in the primate ventral midbrain.

Overexpression of human alpha-synuclein (alpha-syn) using recombinant adeno-associated viral (rAAV) vectors provides a novel tool to study neurodegenerative processes seen in Parkinson's disease and other synucleinopathies. We used a pseudotyped rAAV2/5 vector to express human wild-type (wt) alpha-syn, A53T mutated alpha-syn, or the green fluorescent protein (GFP) in the primate ventral midbrain.

A Palaeolithic diet improves glucose tolerance more than a Mediterranean-like diet in individuals with ischaemic heart disease.

Aims/hypothesis Most studies of diet in glucose intolerance and type 2 diabetes have focused on intakes of fat, carbohydrate, fibre, fruits and vegetables. Instead, we aimed to compare diets that were available during human evolution with more recently introduced ones. Methods Twenty-nine patients with ischaemic heart disease plus either glucose intolerance or type 2 diabetes were randomised to re

Recurrent thromboembolism in pregnancy and puerperium. Is there a need for thromboprophylaxis?

By sending a questionnaire (response rate 93%) to 321 women with a history of venous thromboembolism and previous coagulation tests, 72 patients were identified who had a total of 87 pregnancies after the thromboembolic episode. The main aim of the study was to analyze the influence of prophylaxis during pregnancy and delivery on the development of further thromboembolic complications. During preg