Here, in an analysis of a 2.92 fb–1 data sample taken at 3.773 GeV with the BESIII detector operated at the BEPCII collider, we measure the absolute decay branching fractions to be B(D0 → K–e+νe) = ...(3.505 ± 0.014 ± 0.033)% and B(D0 → π–e+νe) = (0.295 ± 0.004 ± 0.003)%. From a study of the differential decay rates we obtain the products of hadronic form factor and the magnitude of the CKM matrix element $f$ $^{K}_{+}$(0)|Vcs| = 0.7172 ± 0.0025 ± 0.0035 and $f$ $^{π}_{+}$(0)|Vcd| = 0.1435 ± 0.0018 ± 0.0009.
Summary
Our study demonstrated a high incidence of recollapse of the augmented vertebrae after PVP treatment for OVCFs. A risk score based on all significant factors can predict the rate of ...recollapse and gain clinical benefits to prevent recollapse in patients at high risk.
Background
Recollapse of the augmented vertebrae after percutaneous vertebroplasty (PVP) treatment for osteoporotic vertebral compression fractures (OVCFs) has obtained much attention. However, little is known about risk factors and score for recollapse of the augmented vertebrae.
Objective
To determine risk factors and furthermore develop a risk score related to recollapse of the augmented vertebrae after PVP treatment for OVCFs.
Methods
Patients who were treated with PVP for single OVCFs and met this study’s inclusion criteria were retrospectively reviewed. The follow-up period was at least 2 years. Associations of recollapse with co-variates (age, gender, bone mass density BMD with a T-score, fracture level, intravertebral cleft IVC, fracture type, cement volume, cement leakage, leakage into a disc, cement distribution pattern, Non-PMMA-endplate-contact NPEC, preoperative fracture severity, reduction rate RR, reduction angle RA) were analyzed and a risk score for recollapse was further developed to predict recollapse.
Results
A total of 152 patients were included. Recollapse group was found in 42 (27.6%) patients. Preoperative IVC, solid lump cement distribution pattern, more RR (a cutoff value of 7%) and larger RA (a cutoff value of 3°) was significantly associated with increased risk for recollapse of the augmented vertebrae. A risk score was developed based on the number of risk factors present in each patient. Patients with a score of 4 had an approximately ninefold increased risk of developing recollapse over patients with a score of 0. The receiver operating characteristic curve of the risk score generated an area under the curve of 0.899 (95% CI 0.642–0.836,
P
= 0.000).
Conclusion
A risk score based on preoperative IVC, cement distribution pattern, reduction rate, and reduction angle predicts the rate of recollapse. Additional studies should aim to validate this score and inspect clinical benefits of recollapse prophylaxis in patients at high risk.
Based on a sample of ( 10.09±0.04 ) ×109 J/ψ events collected with the BESIII detector operating at the BEPCII storage ring, a partial wave analysis of the decay J/ψ → γηη' is performed. An isoscalar ...state with exotic quantum numbers JPC=1-+ , denoted as η1 ( 1855 ) , has been observed for the first time with statistical significance larger than 19σ . Its mass and width are measured to be ( 1855±9-1+6 ) MeV/c2 and ( 188±18-8+3 ) MeV , respectively. The first uncertainties are statistical and the second are systematic. The product branching fraction B ( J/ψ → γη1 ( 1855 ) ) B ( η1 ( 1855 ) → ηη' ) is measured to be ( 2.70±0.41-0.35+0.16 ) ×10-6 . In addition, an upper limit on the ratio of branching fractions B ( f0 ( 1710 ) → ηη' ) / B ( f0 ( 1710 ) → ππ ) is determined to be 1.61×10-3 at 90% confidence level, which lends support to the hypothesis that the f0 ( 1710 ) has a large glueball component.
Transiting extrasolar planets constitute only a small fraction of the range of stellar systems found to display periodic, shallow dimmings in wide-field surveys employing small-aperture camera ...arrays. Here we present an efficient selection strategy for follow-up observations, derived from analysis of the light curves of a sample of 67 SuperWASP targets that passed the selection tests we used in earlier papers, but which have subsequently been identified either as planet hosts or as astrophysical false positives. We determine the system parameters using Markov-chain Monte Carlo analysis of the SuperWASP light curves. We use a constrained optimization of χ2 combined with a Bayesian prior based on the main-sequence mass and radius expected from the Two Micron All Sky Survey J−H colour. The Bayesian nature of the analysis allows us to quantify both the departure of the host star from the main-sequence mass–radius relation and the probability that the companion radius is less than 1.5 Jupiter radii. When augmented by direct light-curve analyses that detect binaries with unequal primary and secondary eclipses, and objects with aperture blends that are resolved by SuperWASP, we find that only 13 of the original 67 stars, including the three known planets in the sample, would qualify for follow-up. This suggests that planet discovery ‘hit rates’ better than one-in-five should be achievable. In addition, the stellar binaries that qualify are likely to have astrophysically interesting stellar or substellar secondaries.
Quantum sensing based on exotic quantum states is appealing for practical metrology applications and fundamental studies. However, these quantum states are vulnerable to noise and the resulting ...quantum enhancement is weakened in practice. Here, we experimentally demonstrate a quantum-enhanced sensing scheme with a bosonic probe, by exploring the large Hilbert space of the bosonic mode and developing both the approximate quantum error correction and the quantum jump tracking approaches. In a practical radiometry scenario, we attain a 5.3 dB enhancement of sensitivity, which reaches 9.1 × 10
Hz
when measuring the excitation population of a receiver mode. Our results demonstrate the potential of quantum sensing with near-term quantum technologies, not only shedding new light on the quantum advantage of sensing, but also stimulating further efforts on bosonic quantum technologies.
Nickel–cobalt oxides were prepared by coprecipitation of their hydroxides precursors and a following thermal treatment under a moderate temperature. The preformed nickel-cobalt bimetallic hydroxide ...exhibited a flower-like morphology with single crystalline nature and composed of many interconnected nanosheets. The ratio of Ni to Co in the oxides could easily be controlled by adjusting the composition of the original reactants for the preparation of hydroxide precursors. It was found that both the molecular ratio of Ni to Co and the annealing temperature had significant effects on their porous structure and electrochemical properties. The effect of the Ni/Co ratio on the pseudocapacitive properties of the binary oxide was investigated in this work. The binary metal oxide with the exact molar ratio of Ni:Co = 0.8:1 annealed at 300 °C, showing an optimum specific capacitance of 750 F/g. However, too high an annealing temperature would lead to a large crystal size, a low specific surface area, as well as a much lower pore volume. With the use of the binary metal oxide with Ni:Co = 0.8:1 and activated carbon as the positive and negative electrode, respectively, the assembled hybrid capacitor could exhibit a high-energy density of 34.9 Wh/kg at the power density of 875 W/kg and long cycling life (86.4% retention of the initial value after 10000 cycles).
DnaJ/Hsp40 (heat shock protein 40) proteins have been preserved throughout evolution and are important for protein translation, folding, unfolding, translocation, and degradation, primarily by ...stimulating the ATPase activity of chaperone proteins, Hsp70s. Because the ATP hydrolysis is essential for the activity of Hsp70s, DnaJ/Hsp40 proteins actually determine the activity of Hsp70s by stabilizing their interaction with substrate proteins. DnaJ/Hsp40 proteins all contain the J domain through which they bind to Hsp70s and can be categorized into three groups, depending on the presence of other domains. Six DnaJ homologs have been identified in Escherichia coli and 22 in Saccharomyces cerevisiae. Genome-wide analysis has revealed 41 DnaJ/Hsp40 family members (or putative members) in humans. While 34 contain the typical J domains, 7 bear partially conserved J-like domains, but are still suggested to function as DnaJ/ Hsp40 proteins. DnaJA2b, DnaJB1b, DnaJC2, DnaJC20, and DnaJC21 are named for the first time in this review; all other human DnaJ proteins were dubbed according to their gene names, e.g. DnaJA1 is the human protein named after its gene DNAJA1. This review highlights the progress in studying the domains in DnaJ/Hsp40 proteins, introduces the mechanisms by which they interact with Hsp70s, and stresses their functional diversity.
A viscous damping model is proposed based on a simplified equation of fluid motion in a moonpool or the narrow gap formed by two fixed boxes. The model takes into account the damping induced by both ...flow separation and wall friction through two damping coefficients, namely, the local and friction loss coefficients. The local loss coefficient is determined through specifically designed physical model tests in this work, and the friction loss coefficient is estimated through an empirical formula found in the literature. The viscous damping model is implemented in the dynamic free-surface boundary condition in the gap of a modified potential flow model. The modified potential flow model is then applied to simulate the wave-induced fluid responses in a narrow gap formed by two fixed boxes and in a moonpool for which experimental data are available. The modified potential flow model with the proposed viscous damping model works well in capturing both the resonant amplitude and frequency under a wide range of damping conditions.
The corrosion and electrochemical behaviour of carefully prepared ultra-lightweight magnesium-lithium (Mg-Li) alloys were investigated and compared. The alloy compositions studied were selected to ...provide the ability to compare unique microstructures and crystal structures, which arise from specific alloying additions of Li. Mg-4%Li is hexagonal closed-packed (HCP) alloy with Li in solid solution of Mg (α-Mg); Mg-14%Li is a fully solid solution BCC (β-Li) alloy, whilst Mg-7.5%Li is a duplex (α-Mg + β-Li) alloy. Testing in 0.1 M NaCl revealed that the corrosion performance and electrochemical response of the Mg-Li system evolved with the composition and crystallographic structure. For Mg-4%Li alloy, filiform-like corrosion morphology can be observed on the corroded surface, whilst a mixture of filiform-like corrosion to the α-Mg and localised dissolution of β-Li existed on the corroded surface of Mg-7.5%Li alloy. In the case of the BCC structured Mg-14%Li alloy, minor pitting was observed, concomitant with a generally low corrosion rate (particularly low corrosion rate for typical Mg alloys) and an increasing corrosion resistance with exposure time were also revealed. A combination of exposure testing inclusive of hydrogen collection and mass loss, in addition to potentiodynamic polarisation and impedance spectroscopy elucidated and quantified the corrosion performance of three differently structured Mg-Li alloys. It revealed that in spite of being composed of reactive elements of Mg and Li, the formation of β-Li phases with BCC structure could facilitate the formation of a highly protective surface film which results in a predictable and consistently low corrosion rate of the Mg-14%Li alloy.
•Corrosion behaviour was dependent on the crystal structure of Mg-Li alloys.•Mg-4Li, Mg-7.5Li and Mg-14Li (wt.%) alloys were HCP, HCP + BCC and BCC structure, respectively.•Corrosion attack preferentially occurred in α-Mg phase of Mg-7.5Li alloy.•Mg-14Li alloy revealed a high corrosion resistance which increased with immersion time.•A highly protective surface film could form on Mg-14Li alloy with single β-Li phase.
Non-Hermitian systems generically have complex energies, which may host topological structures, such as links or knots. While there has been great progress in experimentally engineering non-Hermitian ...models in quantum simulators, it remains a significant challenge to experimentally probe complex energies in these systems, thereby making it difficult to directly diagnose complex-energy topology. Here, we experimentally realize a two-band non-Hermitian model with a single trapped ion whose complex eigenenergies exhibit the unlink, unknot, or Hopf link topological structures. Based on non-Hermitian absorption spectroscopy, we couple one system level to an auxiliary level through a laser beam and then experimentally measure the population of the ion on the auxiliary level after a long period of time. Complex eigenenergies are then extracted, illustrating the unlink, unknot, or Hopf link topological structure. Our work demonstrates that complex energies can be experimentally measured in quantum simulators via non-Hermitian absorption spectroscopy, thereby opening the door for exploring various complex-energy properties in non-Hermitian quantum systems, such as trapped ions, cold atoms, superconducting circuits, or solid-state spin systems.
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