130 research outputs found
Vacuum induced transparency and photon number resolved Autler-Townes splitting in a three-level system
We study the absorption spectrum of a probe field by a {\Lambda}-type
three-level system, which is coupled to a quantized control field through the
two upper energy levels. The probe field is applied to the ground and the
second excited states. When the quantized control field is in vacuum, we derive
a threshold condition to discern vacuum induced transparency (VIT) and vacuum
induced Autler- Townes splitting (ATS). We also find that the parameter change
from VIT to vacuum induced ATS is very similar to that from broken PT symmetry
to PT symmetry. Moreover, we find the photon number resolved spectrum in the
parameter regime of vacuum induced ATS when the mean photon number of the
quantized control field is changed from zero (vacuum) to a finite number.
However, there is no photon number resolved spectrum in the parameter regime of
VIT even that the quantized control field contains the finite number of
photons. Finally, we further discuss possible experimental realization
Decoherence and dynamical decoupling control of nitrogen-vacancy center electron spins in nuclear spin baths
We theoretically study the decoherence and the dynamical decoupling control
of nitrogen-vacancy center electron spins in high-purity diamond, where the
hyperfine interaction with C nuclear spins is the dominating decoherence
mechanism. The decoherence is formulated as the entanglement between the
electron spin and the nuclear spins, which is induced by nuclear spin bath
evolution conditioned on the electron spin state. The nuclear spin bath
evolution is driven by elementary processes such as single spin precession and
pairwise flip-flops. The importance of different elementary processes in the
decoherence depends on the strength of the external magnetic field.Comment: 18 pages, 17 figure
Three new species of Cortinarius section Delibuti (Cortinariaceae, Agaricales) from China
Three new species of Cortinarius section Delibuti, namely C. fibrillososalor, C. pseudosalor, and C. subtropicus are described as new to science based on morphological and phylogenetic evidences. Cortinarius pseudosalor is extremely morphologically similar to C. salor, but it differs from the latter by smaller coarsely verrucose basidiospores. Cortinarius fibrillososalor can be easily differentiated by its fibrillose pileus. The pileus of C. subtropicus becomes brown without lilac tint at maturity comparing with other members of section Delibuti. A combined dataset of ITS and LSU sequences was used for phylogenetic analysis. The phylogenetic reconstruction of section Delibuti revealed that these three new species clustered and formed independent lineages with full support respectively. A key to the three new species and related species of section Delibuti is provided in this work
The Long-term Monitoring Results of Insight-HXMT in the First 4 Yr Galactic Plane Scanning Survey
The first X-ray source catalog of Insight-HXMT Galactic Plane (|b|<10deg)
Scanning Survey (GPSS) is presented based on the data accumulated from June
2017 to August 2021. The 4 yr limit sensitivities at main energy bands can
reach 8.2x10^(-12) erg/s/cm^2} (2-6 keV), 4.21x10^(-11) erg/s/cm^2 (7-40 keV)
and 2.78x10^(-11) erg/s/cm^2 (25-100 keV). More than 1300 sources have been
monitored at a wide band (1100\,keV), of which 223 sources have a
signal-to-noise ratio greater than 5. We combined the GPSS data of Insight-HXMT
and MAXI and found it is feasible to obtain more complete long-term light
curves from their scanning results. The flux variabilities at different energy
bands of the 223 bright sources are analyzed based on the excess variances. It
is found that the fluxes of X-ray binaries are more active than those of
supernova remnants and isolated pulsars. Different types of binaries, e.g.,
low-mass X-ray binaries (LMXBs), high-mass X-ray binaries (HMXBs), neutron star
binaries, and black hole binaries, also distinctively show different
regularities. In addition, the relations between the hardness ratio (HR) and
excess variances, and HR and source types are analyzed. It is obvious that the
HRs of HMXBs tend to be harder than those of LMXBs and HMXBs tend to be more
active than those of LMXBs.Comment: 43 pages, 26 figures, accepted for publication in ApJ
Overproduction of Mitochondrial Fission Proteins in Membranous Nephropathy in Children
Background/Aims: The molecules involved in nephrotic syndrome (NS) have not been fully clarified. Mitochondrial fission proteins are found to be involved in podocyte injury in vitro. Increased glomerular expression of mitochondrial fission proteins was found in adriamycin nephropathy in our previous study. Whether or not mitochondrial fission proteins are involved in podocyte injury in NS is not clear. This study explored the glomerular expression and possible pathological significance of mitochondrial fission-associated proteins, including dynamin-related protein 1 (Drp1) and mitochondrial fission protein 1 (Fis1), in children with NS. Methods: Eighteen children with primary NS, including 6 with minimal change disease, 6 with focal segmental glomerulosclerosis, 6 with membranous nephropathy, 6 children with isolated haematuria and 3 normal controls were included. The glomerular expression of Drp1, phospho-Drp1 (Ser616) and Fis1, urinary protein measurements, and podocyte mitochondrial density under electron microscopy were investigated and compared. Results: Glomerular expression of Drp1, phospho-Drp1 (Ser616) and Fis1 was mainly increased in children with NS with membranous nephropathy. No relationship was found between glomerular expression of Drp1, phospho-Drp1 (Ser616) and Fis1 and podocyte mitochondrial density or urinary protein measurements. Conclusion: Glomerular overproduction of Drp1, phospho-Drp1 (Ser 616) and Fis1 occurred mainly in children with membranous nephropathy. The pathological significance deserves further investigation
Plasma Levels of Amino Acids Related to Urea Cycle and Risk of Type 2 Diabetes Mellitus in Chinese Adults
Objective: This study aimed to test associations between type 2 diabetes mellitus (T2DM) and metabolites in urea cycle including arginine, citrulline and ornithine.Methods:This study used a hospital-based cross-sectional study design. We retrieved medical notes of 401 in-patients with onset of T2DM within 2 years and 1,522 healthy subjects who attended annual physical examination. All cases were admitted to a tertiary care center in Jinzhou, China from May 2015 to August 2016. Binary logistic regression analyses were performed to obtain odds ratios (ORs) and 95% confidence intervals (CIs).Results:Patients with T2DM had higher arginine, and lower ornithine than control subjects. Levels of citrulline were similar in two groups. Arginine was positively associated with T2DM (ORs: 1.20, 1.17–1.23) while ornithine was negatively associated with T2DM (OR: 0.89, 0.88–0.91). After adjustment for other amino acids and traditional risk factors, these associations were still significant and persistent for arginine and ornithine. The association between citrulline and T2DM was not significant. Their ratios of pairs of two amino acids were associated with increased risk of T2DM. After adjustment for other ratios of amino acids, effect size for T2DM remained significant. Further adjustment for traditional risk factors did not lead to large changes (ORs: 1.78, 1.20–2.65 for the ratio of arginine to ornithine; ORs: 1.59, 1.37–1.86 for the ratio of citrulline to ornithine, respectively) except the ratio of arginine to citrulline.Conclusions: Plasma levels of amino acids related to urea cycle and their ratios of these amino-acids were associated with T2DM in Chinese adults
- …