2,417 research outputs found
Rotational Doppler effect in left-handed materials
We explain the rotational Doppler effect associated with light beams carrying
with orbital angular momentum in left-handed materials (LHMs). We demonstrate
that the rotational Doppler effect in LHMs is unreversed, which is
significantly different from the linear Doppler effect. The physics underlying
this intriguing effect is the combined contributions of negative phase velocity
and inverse screw of wave-front. In the normal dispersion region, the
rotational Doppler effect induces a upstream energy flow but a downstream
momentum flow. In the anomalous dispersion region, however, the rotational
Doppler effect produces a downstream energy flow but a upstream momentum flow.
We theoretically predict that the rotational Doppler effect can induce a
transfer of angular momentum of the LHM to orbital angular momentum of the
beam.Comment: 6 pages, 3 figure
Investigation of Stellar Kinematics and Ionized gas Outflows in Local [U]LIRGs
We explore properties of stellar kinematics and ionized gas in a sample of
1106 local [U]LIRGs from the AKARI telescope. We combine data from $Wide-field\
Infrared\ Survey\ Explorer\beta\alpha\sim\sim\sim^{-1}\sim 60
\solarm~yr^{-1}$). Our results suggest that starbursts are insufficient to
produce such powerful outflows. We explore the correlations of SFR and specific
SFR (sSFR) with ionized gas outflows. We find that AGN hosts with the highest
SFRs exhibit a negative correlation between outflow velocity and sSFR.
Therefore, in AGNs containing large amounts of gas, the negative feedback
scenario might be suggested.Comment: 20 pages, 14 figures, accepted for publication in Ap
Case report: Three novel variants on SLC25A13 in four infants with neonatal intrahepatic cholestasis caused by citrin deficiency
BackgroundNeonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) is a common clinical phenotype of citrin deficiency in infants. Its phenotype is atypical, so genetic testing is quite necessary for the diagnosis.Case presentationWe report 4 patients with jaundice and low body weight. Furthermore, the biochemical examination of all showed abnormal liver function and metabolic changes. DNA samples of the patients were extracted and subjected to genetic screening. All candidate pathogenic variants were validated by Sanger sequencing, and CNVs were ascertained by qPCR. The genetic screening revealed 6 variants in 4 patients, and all patients carried compound heterozygous variants of SLC25A13. Importantly, 3 variants were newly discovered: a nonsense mutation in exon17 (c.1803C > G), a frameshift mutation in exon 11(c.1141delG) and a deletion of the whole exon11. Thus, four NICCD patients were clearly caused by variants of SLC25A13. Biochemical indicators of all patients gradually returned to normal after dietary adjustment.ConclusionsOur study clarified the genetic etiology of the four infants, expanded the variant spectrum of SLC25A13, and provided a basis for genetic counseling of the family. Early diagnosis and intervention should be given to patients with NICCD
Enriched oxygen improves age-related cognitive impairment through enhancing autophagy
Age-related cognitive impairment represents a significant health concern, with the understanding of its underlying mechanisms and potential interventions being of paramount importance. This study aimed to investigate the effects of hyperbaric oxygen therapy (HBOT) on cognitive function and neuronal integrity in aged (22-month-old) C57BL/6 mice. Male mice were exposed to HBOT for 2 weeks, and spatial learning and memory abilities were assessed using the Morris water maze. We employed transcriptome sequencing and Gene Ontology (GO) term enrichment analysis to examine the effects of HBOT on gene expression profiles, with particular attention given to synapse-related genes. Our data indicated a significant upregulation of postsynapse organization, synapse organization, and axonogenesis GO terms, likely contributing to improved cognitive performance. Moreover, the hyperphosphorylation of tau, a hallmark of many neurodegenerative diseases, was significantly reduced in the HBO-treated group, both in vivo and in vitro. Transmission electron microscopy revealed significant ultrastructural alterations in the hippocampus of the HBOT group, including an increase in the number of synapses and the size of the active zone, a reduction in demyelinated lesions, and a decreased number of “PANTHOS.” Furthermore, Western blot analyses confirmed the upregulation of PSD95, BDNF, and Syn proteins, suggesting enhanced synaptic plasticity and neurotrophic support. Moreover, HBOT increased autophagy, as evidenced by the elevated levels of Beclin-1 and LC3 proteins and the reduced level of p62 protein. Finally, we demonstrated that HBOT activated the AMPK-mTOR signaling pathway, a critical regulator of autophagy. Notably, our findings provide novel insights into the mechanisms by which HBOT ameliorates age-related cognitive impairment, suggesting the potential therapeutic value of this approach
Stationary perturbation configurations in a composite system of stellar and coplanarly magnetized gaseous singular isothermal discs
We construct aligned and unaligned stationary perturbation configurations in
a composite system of stellar and coplanarly magnetized gaseous singular
isothermal discs (SIDs) coupled by gravity. In comparison with SID problems
studied earlier, there exist three possible classes of stationary solutions
allowed by more dynamic freedoms. Our exact global perturbation solutions and
critical points are valuable for testing numerical magnetohydrodynamic codes.
For galactic applications, our model analysis contains more realistic elements
and offer useful insights for structures and dynamics of disc galaxies
consisting of stars and magnetized gas.Comment: 25 pages, 31 figures, accepted by Monthly Notices of Royal
Astronomical Society, style files include
The First Data Release of the Beijing-Arizona Sky Survey
The Beijing-Arizona Sky Survey (BASS) is a new wide-field legacy imaging
survey in the northern Galactic cap using the 2.3m Bok telescope. The survey
will cover about 5400 deg in the and bands, and the expected
5 depths (corrected for the Galactic extinction) in the two bands are
24.0 and 23.4 mag, respectively. BASS started observations in January 2015, and
has completed about 41% of the whole area as of July 2016. The first data
release contains both calibrated images and photometric catalogs obtained in
2015 and 2016. The depths of single-epoch images in the two bands are 23.4 and
22.9 mag, and the full depths of three epochs are about 24.1 and 23.5 mag,
respectively.Comment: 16 pages, published by A
On the Monitoring of Simple Linear Berkson Profiles
[[abstract]]We consider the quality of a process, which can be characterized by a simple linear Berkson profile. One existing approach for monitoring the simple linear profile and two new proposed schemes are studied for charting the simple linear Berkson profile. Simulation studies demonstrate the effectiveness and efficiency of one of the proposed monitoring schemes. In
addition, a systematic diagnostic approach is provided to spot the change point location of the process and to identify the parameter of change in the profile. Finally, an example from semiconductor manufacturing is used to illustrate the implementation of the proposed monitoring scheme and diagnostic approach.[[incitationindex]]SCI[[booktype]]電子版[[booktype]]紙
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