175 research outputs found
A microwave resonator integrated on a polymer microfluidic chip
We describe a novel stacked split-ring type microwave (MW) resonator that is integrated into a 10 mm by 10 mm sized microfluidic chip. A straightforward and scalable batch fabrication process renders the chip suitable for single-use applications. The resonator volume can be conveniently loaded with liquid sample via microfluidic channels patterned into the mid layer of the chip. The proposed MW resonator offers an alternative solution for compact in-field measurements, such as low-field magnetic resonance (MR) experiments requiring convenient sample exchange. A microstrip line was used to inductively couple MWs into the resonator. We characterised the proposed resonator topology by electromagnetic (EM) field simulations, a field perturbation method, as well as by return loss measurements. Electron paramagnetic resonance (EPR) spectra at X-band frequencies were recorded, revealing an electron-spin sensitivity of View the MathML source3.7·1011spins·Hz-1/2G-1 for a single EPR transition. Preliminary time-resolved EPR experiments on light-induced triplet states in pentacene were performed to estimate the MW conversion efficiency of the resonator
Phosphorylation of proteins in chick ciliary ganglion under conditions that induce long-lasting changes in synaptic transmission:phosphoprotein targets for nitric oxide action
Oscillator strengths for transitions to Rydberg levels in , and between 967 and 972 A
Absorption oscillator strengths have been determined from high-resolution
spectra in the 967-972 \AA region of three CO isotopomers for transitions to
the Rydberg levels 4{\it p}(0), 3{\it d}(1) and 4{\it p}(0),
as well as to the mixed {\it E(6)} level recently characterized by Eidelsberg
et al. (2004). Synchrotron radiation from the Super-ACO electron storage ring
at Orsay (LURE) was used as a light source. Oscillator strengths were extracted
from the recorded spectra by least-squares fitting of the experimental profiles
with synthetic spectra taking into account the homogeneous and heterogeneous
interactions of the four levels. Column densities were derived from fits to the
3{\it p}(0) absorption band whose oscillator strength is well established.
These are the first reported measurements for CO. For
CO, our results are consistent with the larger values obtained in
the most recent laboratory and astronomical studies.Comment: 9 pages 7 figures 3 tables. Accepted in A&A, date of acceptance
11/05/200
High Resolution HST-STIS Spectra of CI and CO in the Beta Pictoris Circumstellar Disk
High resolution FUV echelle spectra showing absorption features arising from
CI and CO gas in the Beta Pictoris circumstellar (CS) disk were obtained on
1997 December 6 and 19 using the Space Telescope Imaging Spectrograph (STIS).
An unsaturated spin-forbidden line of CI at 1613.376 A not previously seen in
spectra of Beta Pictoris was detected, allowing for an improved determination
of the column density of CI at zero velocity relative to the star (the stable
component), N = (2-4) x 10^{16} cm^{-2}. Variable components with multiple
velocities, which are the signatures of infalling bodies in the Beta Pictoris
CS disk, are observed in the CI 1561 A and 1657 A multiplets. Also seen for the
first time were two lines arising from the metastable singlet D level of
carbon, at 1931 A and 1463 A The results of analysis of the CO A-X (0-0),
(1-0), and (2-0) bands are presented, including the bands arising from {13}^CO,
with much better precision than has previously been possible, due to the very
high resolution provided by the STIS echelle gratings. Only stable CO gas is
observed, with a column density N(CO) = (6.3 +/- 0.3) x 10^{14} cm{-2}. An
unusual ratio of the column densities of {12}^CO to {13}^CO is found (R = 15
+/- 2). The large difference between the column densities of CI and CO
indicates that photodissociation of CO is not the primary source of CI gas in
the disk, contrary to previous suggestion.Comment: 13 pages, including 6 figures. LaTex2e (emulateapj5.sty). Accepted
for publication in Ap
Oscillator Strengths and Predissociation Rates for Rydberg Transitions in 12C16O, 13C16O, and 13C18O Involving the E 1Pi, B 1Sigma+, and W 1Pi States
One of the processes controlling the interstellar CO abundance and the ratio
of its isotopologues is photodissociation. Accurate oscillator strengths and
predissociation rates for Rydberg transitions are needed for modeling this
process. We present results on absorption from the E ^1Pi-X ^1Sigma^+ (1-0) and
B ^1Sigma^+-X ^1Sigma^+ (6-0) bands at 1051 and 1002 \AA, respectively, and the
vibrational progression W ^1Pi-X ^1Sigma^+ (v'-0) bands with v' = 0 to 3 at
972, 956, 941, and 925 \AA, respectively. The corresponding spectra were
acquired at the high resolution (R ~ 30,000) SU5 beam line at the Super ACO
Synchrotron in Orsay, France. Spectra were obtained for the ^12C^16O, ^13C^16O,
and ^13C^18O isotopologues. These represent the most complete set of
measurements available. Comparison is made with earlier results, both empirical
and theoretical. While earlier determinations of oscillator strengths based on
absorption from synchrotron radiation tend to be somewhat smaller than ours,
the suite of measurements from a variety of techniques agree for the most part
considering the mutual uncertainties. For the bands studied here, their
relative weakness, or their significant line widths arising from
predissociation, minimizes potential problems from large optical depths at line
center in absorption measurements. Predissociating line widths could generally
be extracted from the spectra thanks to the profile simulations used in the
analysis. In many cases, these simulations allowed us to consider e and f
parity levels separately and to determine the dependence of the width on
rotational quantum number, J. Our results are consistent with earlier
determinations, especially the widths inferred from laser experiments
Supporting Roma Voices
The Supporting Roma Voice project has aimed to
address emerging knowledge gaps in the way in
which the inclusion of migrant Roma in the UK is
being addressed. Specifically, research by Brown,
Scullion and Martin (2013) identified a demand
from public authorities for social inclusion work
directed towards migrant Roma communities to be
developed and delivered by members of migrant
Roma communities themselves. However, what was
also lacking was an adequate evidence base about
the settlement of migrant Roma in the UK and the
varied experiences associated with this transition.
This report explores the views and experiences of a
large number of Roma people who have migrated
to the UK in recent years. The research was
designed in partnership with a team of researchers
from the Roma communities and undertaken
wholly by these researchers. The research study
aimed to explore the following issues:
- The settlement and integration experiences of
Roma migrants living in areas across the UK.
- The specific areas of community relations,
housing, education, employment and social
welfare and their role in settlement in the UK.
- The provision of knowledge that would enable
local authorities and other services to enhance
the settlement experience of Roma migrants
now and in the future.
A total of 159 people participated in 19 focus
groups, which took place in the following locations:
Glasgow, Leicester, London, Oldham, Salford and
Sheffield. It should be noted that owing to the
heterogeneity of the Roma population this report
does not attempt to make definitive statements
about the situation and views of all Roma
migrants in the UK. This report was co-authored
by members of the academic team in partnership
with community researchers. The fieldwork
was undertaken in early 2016 prior to the UK’s
referendum on staying in the European Union
Phosphorylation of proteins in chick ciliary ganglion under conditions that induce long-lasting changes in synaptic transmission:phosphoprotein targets for nitric oxide action
Rescuing impairment of long-term potentiation in fyn-deficient mice by introducing Fyn transgene
Social Transfer of Pathogenic Fungus Promotes Active Immunisation in Ant Colonies
Social contact with fungus-exposed ants leads to pathogen transfer to healthy nest-mates, causing low-level infections. These micro-infections promote pathogen-specific immune gene expression and protective immunization of nest-mates
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