96 research outputs found
Low temperature ellipsometry of NaV2O5
The dielectric function of alpha'NaV2O5 was measured with electric field
along the a and b axes in the photon energy range 0.8-4.5 eV for temperatures
down to 4K. We observe a pronounced decrease of the intensity of the 1 eV peak
upon increasing temperature with an activation energy of about 25meV,
indicating that a finite fraction of the rungs becomes occupied with two
electrons while others are emptied as temperature increases. No appreciable
shifts of peaks were found s in the valence state of individual V atoms at the
phase transition is very small. A remarkable inflection of this temperature
dependence at the phase transition at 34 K indicates that charge ordering is
associated with the low temperature phase.Comment: Revisions in style and order of presentation. One new figure. In
press in Physical Review B. REVTeX, 4 pages with 4 postscript figure
Alteration of Striatal Dopaminergic Neurotransmission in a Mouse Model of DYT11 Myoclonus-Dystonia
Background: DYT11 myoclonus-dystonia (M-D) syndrome is a neurological movement disorder characterized by myoclonic jerks and dystonic postures or movement that can be alleviated by alcohol. It is caused by mutations in SGCE encoding e-sarcoglycan (e-SG); the mouse homolog of this gene is Sgce. Paternally-inherited Sgce heterozygous knockout (Sgce KO) mice exhibit myoclonus, motor impairment and anxiety- and depression-like behaviors, modeling several clinical symptoms observed in DYT11 M-D patients. The behavioral deficits are accompanied by abnormally high levels of dopamine and its metabolites in the striatum of Sgce KO mice. Neuroimaging studies of DYT11 M-D patients show reduced dopamine D2 receptor (D2R) availability, although the possibility of increased endogenous dopamine, and consequently, competitive D2R occupancy cannot be ruled out. Methodology/Principal Findings: The protein levels of striatal D2R, dopamine transporter (DAT), and dopamine D1 receptor (D1R) in Sgce KO mice were analyzed by Western blot. The striatal dopamine release after amphetamine injection in Sgce KO mice were analyzed by microdialysis in vivo. The striatal D2R was significantly decreased in Sgce KO mice without altering DAT and D1R. Sgce KO mice also exhibited a significant increase of dopamine release after amphetamine injection in comparison to wild-type (WT) littermates. Conclusion/Significance: The results suggest e-SG may have a role in the regulation of D2R expression. The loss of e-S
Seasonal transition characteristics of the westerly jet: Study based on field observations at an altitude of 6900 m on the Mt. Xixiabangma Dasuopu glacier
Clinical factors involved in the recurrence of pituitary adenomas after surgical remission: a structured review and meta-analysis
Recessively inherited L-DOPA-responsive parkinsonism in infancy caused by a point mutation (L205P) in the tyrosine hydroxylase gene
Fertilizer and stocking rates on two King Country soils
Parent materials such as volcanic ash and sedimentary siltstone
and sandstone form soils which differ markedly in their physical
and chemical properties. In stocking x fertilizer rate trials on
two families of soils, Te Kuiti-Tumutumu (volcanic ash) and
Mahoenui-Mangatea (siltstonesandstone), the former showed marked
response to increasing rates of superphosphate in terms of
pasture availability and animal production but the latter showed
negligible response above the lowest rate (250 kg/ha). Responses
to superphosphate were apparent on Te Kuiti-Tumutumu only
at the high stocking rate. Sward composition showed no measurable
improvement with the application of superphosphate. Management practices were undoubtedly important in this respect. Differential
‘topdressing should be practised where feasible. When soil
test levels for phosphate are medium to low, Te Kuiti-Tumutumu
soils should receive at least 500 kg/ha/yr of superphosphate,
Mahoenui-Mangatea soils 250 kg/ha/yr. Stocking rates and
management practices must be such as to allow full utilization
of the additional pasture grown
Molecular dissection of a contiguous gene syndrome: Localization of the genes involved in the Langer-Giedion syndrome
The Langer-Giedion syndrome (tricho-rhino-phalangeal syndrome type II, TRPS II) is characterized by craniofacial dysmorphism and skeletal abnormalities. It combines the clinical features of TRPS I and multiple cartilaginous exostoses (EXT). We have used YAC cloning, Southern blotting, PCR analysis, and fluorescence in situ hybridization to study chromosome 8 deletions, translocations, an inversion, and an insertion in patients with TRPS I, TRPS II or EXT. Our results indicate that the TRPS gene maps more than 1,000 kb proximal to the EXT1 gene and that both genes are affected in TRPS II. We conclude that TRPS II is not due to pleiotropic effects of mutations in a single gene, but that it is a true contiguous gene syndrome
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