554 research outputs found
Evidence for charge delocalization crossover in the quantum critical superconductor CeRhIn
The nature of charge degrees-of-freedom distinguishes scenarios for
interpreting the character of a second order magnetic transition at zero
temperature, that is, a magnetic quantum critical point (QCP). Heavy-fermion
systems are prototypes of this paradigm, and in those, the relevant question is
where, relative to a magnetic QCP, does the Kondo effect delocalize their
-electron degrees-of-freedom. Herein, we use pressure-dependent Hall
measurements to identify a finite-temperature scale that signals
a crossover from -localized to -delocalized character. As a function of
pressure, extrapolates smoothly to zero temperature at the
antiferromagnetic QCP of CeRhIn where its Fermi surface reconstructs,
hallmarks of Kondo-breakdown criticality that generates critical magnetic and
charge fluctuations. In 4.4% Sn-doped CeRhIn, however,
extrapolates into its magnetically ordered phase and is decoupled from the
pressure-induced magnetic QCP, which implies a spin-density-wave (SDW) type of
criticality that produces only critical fluctuations of the SDW order
parameter. Our results demonstrate the importance of experimentally determining
to characterize quantum criticality and the associated
consequences for understanding the pairing mechanism of superconductivity that
reaches a maximum in both materials at their respective magnetic
QCP.Comment: 19 pages, 5 figures, published in Nature Communication
Effect of two different exercises on balance, pain and ankle motor function in male college students with chronic ankle instability
Strength and proprioceptive exercise are known to be representative exercise
methods used in patients with chronic ankle instability (CAI) and they are
effective in restoring ankle stability and body balance, which gets reduced by
repetitive ankle sprains. But, there is a lack of data comparing the effects of
strengthening or proprioceptive exercise rehabilitation program for CAI patients.
The purpose of this study is to investigate the effect of a 4-week exercise
program on ankle range of motion (ROM), static/dynamic balance, and drop landing
in college students with CAI. The subjects of this study were 21 male college
students who had the Cumberland ankle instability tool (CAIT) questionnaire
scores of 24 or less, and they were divided into three groups; the non-treated
group (NTG), the traditional strength exercise group (SEG) and the proprioceptive
exercise group (PEG). The exercise rehabilitation program was applied 3 times a
week for 4 weeks. To examine the difference between groups, CAIT, visual analogue
scale (VAS), body composition, ankle ROM, one-leg standing with eyes closed and
Y-balance test (YBT) as well as center of pressure (COP) 95% confidence ellipse
area during drop landing were measured before and after the exercise
intervention. CAIT scores and static balance were significantly increased in the
PEG compared to the NTG and the SEG, and ankle dorsiflexion ROM and Y-balance
were significantly increased in the SEG and the PEG compared to the NTG. In
addition, pain, ankle inversion ROM, and COP 95% confidence ellipse area were
significantly reduced in the SEG and the PEG compared to the NTG. The
proprioceptive exercise program is thought to be effective therapeutic approach
on improving the symptoms of CAI patients
Critical-point anomalies in doped CeRhIn5
The heavy-fermion compound CeRhIn can be tuned through a quantum critical
point, when In is partially replaced by Sn. This way additional charge carriers
are introduced and the antiferromagnetic order is gradually suppressed to zero
temperature. Here we investigate the temperature-dependent optical properties
of CeRh(InSn) single crystals for , and
. With increasing Sn concentration the infrared conductivity reveals a
clear enhancement of the - hybridization strength. At low temperatures we
observed a non-Fermi-liquid behavior in the frequency dependence of the
scattering rate and effective mass in all three compounds. In addition, below a
characteristic temperature K, the temperature dependent
resistivity follows a behavior, typical for a non-Fermi
liquid. The temperature-dependent magnetization also exhibits anomalous
behavior below . Our investigation reveal that below the system
shows a pronounced non-Fermi-liquid behavior and monotonically increases
as the quantum critical point is approached
Structural and histological characterization of oviductal magnum and lectin-binding patterns in Gallus domesticus
<p>Abstract</p> <p>Background</p> <p>Although chicken oviduct is a useful model and target tissue for reproductive biology and transgenesis, little is known because of the highly specific hormonal regulation and the lack of fundamental researches, including lectin-binding activities and glycobiology. Because lectin is attached to secreted glycoproteins, we hypothesized that lectin could be bound to secretory egg-white proteins, and played a crucial role in the generation of egg-white protein in the oviduct. Hence, the purpose of this study was to investigate the structural, histological and lectin-binding characteristics of the chicken oviductal magnum from juvenile and adult hens.</p> <p>Methods</p> <p>The oviductal magnums from juvenile and adult hens were prepared for ultrastructural analysis, qRT-PCR and immunostaining. Immunohistochemistry of anti-ovalbumin, anti-ESR1 and anti-PGR, and mRNA expression of egg-white genes and steroid hormone receptor genes were evaluated. Lectin histochemical staining was also conducted in juvenile and adult oviductal magnum tissues.</p> <p>Results</p> <p>The ultrastructural analysis showed that ciliated cells were rarely developed on luminal surface in juvenile magnum, but not tubular gland cells. In adult magnum, two types of epithelium and three types of tubular gland cells were observed. qRT-PCR analysis showed that egg-white genes were highly expressed in adult oviduct compared with the juvenile. However, mRNA expressions of <it>ESR1 </it>and <it>PGR </it>were considerably higher in juvenile oviduct than adult (<it>P </it>< 0.05). The immunohistochemical analysis showed that anti-ovalbumin antibody was detected in adult oviduct not in juvenile, unlikely anti-ESR1 and anti-PGR antibodies that were stained in both oviducts. In histological analysis, Toluidine blue was stained in juvenile and adult oviductal epithelia, and adult tubular glands located in the outer layer of oviductal magnum. In contrast, PAS was positive only in adult oviductal tubular gland. Lectins were selectively bound to oviductal epithelium, stroma, and tubular gland cells. Particularly, lectin-ConA and WGA were bound to electron-dense secretory granules in tubular gland.</p> <p>Conclusions</p> <p>The observation of ultrastructural analysis, mRNA expression, immunohistochemistry and lectin staining showed structural and physiological characterization of juvenile and adult oviductal magnum. Consequently, oviduct study could be helped to <it>in vitro </it>culture of chicken oviductal cells, to develop epithelial or tubular gland cell-specific markers, and to understand female reproductive biology and endocrinology.</p
Appropriate number of observations for determining hand hygiene compliance among healthcare workers
Abstract
We sought to determine the minimum number of observations needed to determine hand hygiene (HH) compliance among healthcare workers. The study was conducted at a referral hospital in South Korea. We retrospectively analyzed the result of HH monitoring from January to December 2018. HH compliance was calculated by dividing the number of observed HH actions by the total number of opportunities. Optimal HH compliance rates were calculated based on adherence to the six-step technique recommended by the World Health Organization. The minimum number of required observations (n) was calculated by the following equation using overall mean value (ρ), absolute precision (d), and confidence interval (CI) (1 − α) [the equation:
n
≥
Z
α
/
2
2
×
ρ
×
1
-
ρ
/
d
2
]. We considered ds of 5%, 10%, 20%, and 30%, with CIs of 99%, 95%, and 90%. During the study period, 8791 HH opportunities among 1168 healthcare workers were monitored. Mean HH compliance and optimal HH compliance rates were 80.3% and 59.7%, respectively. The minimum number of observations required to determine HH compliance rates ranged from 2 (
d
: 30%, CI: 90%) to 624 (
d
: 5%, CI: 99%), and that for optimal HH compliance ranged from 5 (
d
: 30%, CI: 90%) to 642 (
d
: 5%, CI: 99%). Therefore, we found that our hospital required at least five observations to determine optimal HH compliance
Triple-sinusoid hedgehog lattice in a centrosymmetric Kondo metal
Superposed symmetry-equivalent magnetic ordering wave vectors can lead to
topologically non-trivial spin textures, such as magnetic skyrmions and
hedgehogs, and give rise to novel quantum phenomena due to fictitious magnetic
fields associated with a non-zero Berry curvature of these spin textures. To
date, all known spin textures are constructed through the superposition of
multiple spiral orders, where spins vary in directions with constant amplitude.
Recent theoretical studies have suggested that multiple sinusoidal orders,
where collinear spins vary in amplitude, can construct distinct topological
spin textures regarding chirality properties. However, such textures have yet
to be experimentally realised. In this work, we report the observation of a
zero-field magnetic hedgehog lattice from a superposition of triple sinusoidal
wave vectors in the magnetically frustrated Kondo lattice CePtAl4Ge2. Notably,
we also observe the emergence of anomalous electrical and thermodynamic
behaviours near the field-induced transition from the zero-field topological
hedgehog lattice to a non-topological sinusoidal state. These observations
highlight the role of Kondo coupling in stabilising the zero-field hedgehog
state in the Kondo lattice and warrant an expedited search for other
topological magnetic structures coupled with Kondo coupling
Progress in Understanding and Sequencing the Genome of Brassica rapa
Brassica rapa, which is closely related to
Arabidopsis thaliana, is an important crop and a
model plant for studying genome evolution via
polyploidization. We report the current understanding of the
genome structure of B. rapa and efforts for the
whole-genome sequencing of the species. The tribe
Brassicaceae, which comprises ca. 240 species,
descended from a common hexaploid ancestor with a basic genome
similar to that of Arabidopsis. Chromosome
rearrangements, including fusions and/or fissions, resulted in
the present-day “diploid” Brassica
species with variation in chromosome number and phenotype.
Triplicated genomic segments of B. rapa are
collinear to those of A. thaliana with InDels.
The genome triplication has led to an approximately 1.7-fold
increase in the B. rapa gene number compared to
that of A. thaliana. Repetitive DNA of B.
rapa has also been extensively amplified and has
diverged from that of A. thaliana. For its
whole-genome sequencing, the Brassica rapa Genome
Sequencing Project (BrGSP) consortium has developed suitable
genomic resources and constructed genetic and physical maps.
Ten chromosomes of B. rapa are being allocated to
BrGSP consortium participants, and each chromosome will be
sequenced by a BAC-by-BAC approach. Genome sequencing of
B. rapa will offer a new perspective for plant
biology and evolution in the context of polyploidization
Orbital-selective confinement effect of Ru orbitals in SrRuO ultrathin film
The electronic structure of SrRuO thin film with thickness from 50 to 1
unit cell (u.c.) is investigated via the resonant inelastic x-ray scattering
(RIXS) technique at the O K-edge to unravel the intriguing interplay of orbital
and charge degrees of freedom. We found that orbital-selective quantum
confinement effect (QCE) induces the splitting of Ru orbitals. At the same
time, we observed a clear suppression of the electron-hole continuum across the
metal-to-insulator transition (MIT) occurring at the 4 u.c. sample. From these
two clear observations we conclude that QCE gives rise to a Mott insulating
phase in ultrathin SrRuO films. Our interpretation of the RIXS spectra is
supported by the configuration interaction calculations of RuO clusters.Comment: 7 pages, 7 figure
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