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Phase transitions towards frequency entrainment in large oscillator lattices

We simulate two-dimensional lattices of pulse-coupled oscillators with random natural frequencies, resembling pacemaker cells in the heart. As coupling increases, this system seems to undergo two phase transitions in the thermodynamic limit. First, the largest cluster of frequency entrained oscillators becomes macroscopic. Second, all oscillators frequency entrain, except possibly some isolated on

Brain plasticity and hand function

Popular Abstract in Swedish Nervskador som drabbar händerna orsakar stora problem både för den drabbade i form av försämrad handfunktion och för samhället i form av kostnader på grund av långvarig sjukskrivning. Trots mikrokirurgisk nervreparations teknik med användande av speciella instrument och mikroskop får vuxna patienter ofta bestående besvär med känselbortfall, muskelsvaghet och smärta. AvThe aim of this thesis was to investigate the effects of cortical reorganisational changes following experimental deafferentation and peripheral nerve injury and apply the concept of brain plasticity to enhance sensory re-education following peripheral nerve injury and repair in the hand. In the first two papers the effects on hand function of contralateral deafferentation was investigated. Tourn

Bichir HoxA cluster sequence reveals surprising trends in ray-finned fish genomic evolution

The study of Hox clusters and genes provides insights into the evolution of genomic regulation of development. Derived ray-finned fishes (Actinopterygii, Teleostei) such as zebrafish and pufferfish possess duplicated Hox clusters that have undergone considerable sequence evolution. Whether these changes are associated with the duplication(s) that produced extra Hox clusters is unresolved because c

Electrophysiology and ocular blood flow in a family with dominant optic nerve atrophy and a mutation in the OPA1 gene

OBJECTIVE: To characterize the clinical phenotype, with emphasis on electrophysiology and blood flow measurements, of a family with dominant optic nerve atrophy and an identified mutation in the OPA1 gene. METHODS: Seven family members were examined. Ophthalmological evaluation included testing of visual acuity, ophthalmolscopy, kinetic perimetry, color vision testing, full-field electroretinograp

Orientation of nocturnally migrating Swainson's thrush at dawn and dusk: Importance of energetic condition and geomagnetic cues

We studied the early morning cage orientation of nocturnally migrating Swainson's Thrushes (Catharus ustulatus) during three fall migration seasons. The results were compared with earlier free-flight release tests under starry skies and were found to be consistent with continuation of migratory flights in the expected seasonally appropriate direction. Energetic condition proved decisive: fat birds

Deuteron and triton production with high energy sulphur and lead beams

Proton and deuteron production has been observed in S+S and S+Pb collisions at 200 A-GeV and in Pb+Pb reactions at 158 A-GeV at the CERN SPS accelerator. For Pb+Pb triton production was also measured. The p and d spectra as well as the p and t spectra were observed in similar rapidity ranges and over similar ranges of transverse momenta per nucleon, making it possible to interpret the cross sectio

Role of striatal l-DOPA in the production of dyskinesia in 6-hydroxydopamine lesioned rats.

We explored possible differences in the peripheral and central pharmacokinetics of L-DOPA as a basis for individual variation in the liability to dyskinesia. Unilaterally, 6-hydroxydopamine (6-OHDA) lesioned rats were treated chronically with L-DOPA for an induction and monitoring of abnormal involuntary movements (AIMs). Comparisons between dyskinetic and non-dyskinetic cases were then carried ou

A combination of magnetic permeability detection with nanometer-scaled superparamagnetic tracer and its application for one-step detection of human urinary albumin in undiluted urine

A rapid (6.5 min) and simple one-step magnetic immunoassay (MIA) has been developed for analysis of human urinary albumin in near patient settings. Polyclonal rabbit anti-human albumin was used as a capture antibody and monoclonal mouse anti-human albumin as a detection antibody in a two-site immunometric assay requiring no additional washing procedures. The polyclonal anti-human albumin was conju

Growth and development of larval Rana temporaria: Local variation and countergradient selection

I raised tadpoles of the Common Frog (Rana temporaria) from populations in eight source ponds in southern Sweden, in a common garden experiment at two densities. Tadpoles from different populations differed in development rate; those from source ponds with high tadpole densities developed faster than those from less crowded ponds. Thus, differences among ponds in tadpole performance, which were do

Electrochemical studies on antioxidants in bovine milk

Cyclic voltammetry (CV), rotating disk electrode (RDE) linear sweep voltammetry and flow-injection amperometry (FIAmp) were used to investigate the possibility to determine antioxidants in bovine milk, whey and low-molecular-weight (LMW) fractions of whey. Using CV one major current wave was found in all types of samples at oxidation potentials between +600 and +700 mV against Ag | AgCl|0.1 mol l−