3,621 research outputs found
Doubly resonant optical nanoantenna arrays for polarization resolved measurements of surface-enhanced Raman scattering
We report that rhomb-shaped metal nanoantenna arrays support multiple
plasmonic resonances, making them favorable bio-sensing substrates. Besides the
two localized plasmonic dipole modes associated with the two principle axes of
the rhombi, the sample supports an additional grating-induced surface plasmon
polariton resonance. The plasmonic properties of all modes are carefully
studied by far-field measurements together with numerical and analytical
calculations. The sample is then applied to surface-enhanced Raman scattering
measurements. It is shown to be highly efficient since two plasmonic resonances
of the structure were simultaneously tuned to coincide with the excitation and
the emission wave- length in the SERS experiment. The analysis is completed by
measuring the impact of the polarization angle on the SERS signal.Comment: 13 pages, 5 figure
Molecular characterisation of congenital myasthenic syndromes in Southern Brazil
Objective To perform genetic testing of patients with congenital myasthenic syndromes (CMS) from the Southern Brazilian state of Parana. Patients and methods Twenty-five CMS patients from 18 independent families were included in the study. Known CMS genes were sequenced and restriction digest for the mutation RAPSN p.N88K was performed in all patients. Results We identified recessive mutations of CHRNE in ten families, mutations in DOK7 in three families and mutations in COLQ, CHRNA1 and CHRNB1 in one family each. The mutation CHRNE c. 70insG was found in six families. We have repeatedly identified this mutation in patients from Spain and Portugal and haplotype studies indicate that CHRNE c. 70insG derives from a common ancestor. Conclusions Recessive mutations in CHRNE are the major cause of CMS in Southern Brazil with a common mutation introduced by Hispanic settlers. The second most common cause is mutations in DOK7. The minimum prevalence of CMS in Parana is 0.18/100 000
Molecular characterisation of congenital myasthenic syndromes in Southern Brazil
Objective To perform genetic testing of patients with congenital myasthenic syndromes (CMS) from the Southern Brazilian state of Parana. Patients and methods Twenty-five CMS patients from 18 independent families were included in the study. Known CMS genes were sequenced and restriction digest for the mutation RAPSN p.N88K was performed in all patients. Results We identified recessive mutations of CHRNE in ten families, mutations in DOK7 in three families and mutations in COLQ, CHRNA1 and CHRNB1 in one family each. The mutation CHRNE c. 70insG was found in six families. We have repeatedly identified this mutation in patients from Spain and Portugal and haplotype studies indicate that CHRNE c. 70insG derives from a common ancestor. Conclusions Recessive mutations in CHRNE are the major cause of CMS in Southern Brazil with a common mutation introduced by Hispanic settlers. The second most common cause is mutations in DOK7. The minimum prevalence of CMS in Parana is 0.18/100 000
Designing positive behavior change experiences: a systematic review and sentiment analysis based on online user reviews of fitness and nutrition mobile applications
While mobile devices have become ubiquitous, illnesses derived
from poor lifestyle habits are on the rise. However, our understand ing of design mechanisms that induce healthier behavior change
through mobile devices is still limited. Using the BCT Taxonomy,
and online user reviews as an indicator of experience satisfaction,
we make a three-folded contribution to designing interactive sys tems for behavior change: (i) a systematic review of applications
for physical activity and healthier eating habits, coding BCTs; (ii)
sentiment analysis performed on 20492 review sentences of these
apps; and (iii) design implications regarding the implementation
features for each BCT cluster, considering the highest-scored fea tures in terms of sentiment analysis. Positive expressions referred
to the framing/reframing technique. Contrarily, negative expres sions were mostly related to reward and threat. Findings from this
study can be used to benchmark interactions between users and
behavior change interfaces, and provide design insights to support
positive user experiences.info:eu-repo/semantics/publishedVersio
Bandgap narrowing in Mn doped GaAs probed by room-temperature photoluminescence
The electronic band structure of the (Ga,Mn)As system has been one of the
most intriguing problems in solid state physics over the past two decades.
Determination of the band structure evolution with increasing Mn concentration
is a key issue to understand the origin of ferromagnetism. Here we present room
temperature photoluminescence and ellipsometry measurements of
Ga_{100%-x}Mn_{x}As alloy. The up-shift of the valence-band is proven by the
red shift of the room temperature near band gap emission from the
Ga_{100%-x}Mn_{x}As alloy with increasing Mn content. It is shown that even a
doping by 0.02 at.% of Mn affects the valence-band edge and it merges with the
impurity band for a Mn concentration as low as 0.6 at.%. Both X-ray diffraction
pattern and high resolution cross-sectional TEM images confirmed full
recrystallization of the implanted layer and GaMnAs alloy formation.Comment: 24 pages, 7 figures, accepted at Phys. Rev. B 201
Leukoencephalopathy upon disruption of the chloride channel ClC-2
ClC-2 is a broadly expressed plasma membrane chloride channel that is modulated by voltage, cell swelling, and pH. A human mutation leading to a heterozygous loss of ClC-2 has previously been reported to be associated with epilepsy, whereas the disruption of Clcn2 in mice led to testicular and retinal degeneration. We now show that the white matter of the brain and spinal cord of ClC-2 knock-out mice developed widespread vacuolation that progressed with age. Fluid-filled spaces appeared between myelin sheaths of the central but not the peripheral nervous system. Neuronal morphology, in contrast, seemed normal. Except for the previously reported blindness, neurological deficits were mild and included a decreased conduction velocity in neurons of the central auditory pathway. The heterozygous loss of ClC-2 had no detectable functional or morphological consequences. Neither heterozygous nor homozygous ClC-2 knock-out mice had lowered seizure thresholds. Sequencing of a large collection of human DNA and electrophysiological analysis showed that several ClC-2 sequence abnormalities previously found in patients with epilepsy most likely represent innocuous polymorphisms
Four-qubit device with mixed couplings
We present the first experimental results on a device with more than two
superconducting qubits. The circuit consists of four three-junction flux
qubits, with simultaneous ferro- and antiferromagnetic coupling implemented
using shared Josephson junctions. Its response, which is dominated by the
ground state, is characterized using low-frequency impedance measurement with a
superconducting tank circuit coupled to the qubits. The results are found to be
in excellent agreement with the quantum-mechanical predictions.Comment: REVTeX 4, 5pp., 7 EPS figure files. N.B.: "Alec" is my first, and
"Maassen van den Brink" my family name. v2: final published version, with
changed title, different sample micrograph, and several clarification
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