Precise control of solid-state elastic waves' mode content and coherence is of great use nowadays in reinforcing mechanical energy harvesting/storage, nondestructive material testing, wave-matter ...interaction, high sensitivity sensing, and information processing, etc. Its efficacy is highly dependent on having elastic transmission channels with lower loss and higher degree of freedom. Here, we demonstrate experimentally an elastic analog of the quantum spin Hall effects in a monolithically scalable configuration, which opens up a route in manipulating elastic waves represented by elastic pseudospins with spin-momentum locking. Their unique features including robustness and negligible propagation loss may enhance elastic planar-integrated circuit-level and system-level performance. Our approach promotes topological materials that can interact with solid-state phonons in both static and time-dependent regimes. It thus can be immediately applied to multifarious chip-scale topological phononic devices, such as path-arbitrary elastic wave-guiding, elastic splitters and elastic resonators with high-quality factors.
Stable and efficient guided waves are essential for information transmission and processing. Recently, topological valley-contrasting materials in condensed matter systems have been revealed as ...promising infrastructures for guiding classical waves, for they can provide broadband, non-dispersive and reflection-free electromagnetic/mechanical wave transport with a high degree of freedom. In this work, by designing and manufacturing miniaturized phononic crystals on a semi-infinite substrate, we experimentally realized a valley-locked edge transport for surface acoustic waves (SAWs). Critically, original one-dimensional edge transports could be extended to quasi-two-dimensional ones by doping SAW Dirac "semimetal" layers at the boundaries. We demonstrate that SAWs in the extended topological valley-locked edges are robust against bending and wavelength-scaled defects. Also, this mechanism is configurable and robust depending on the doping, offering various on-chip acoustic manipulation, e.g., SAW routing, focusing, splitting, and converging, all flexible and high-flow. This work may promote future hybrid phononic circuits for acoustic information processing, sensing, and manipulation.
We compile a sample of 93 long gamma-ray bursts (GRBs) from the Fermi satellite and 131 from Konus-Wind that have measured redshifts and well-determined spectra, and estimate their pseudo-Lorentz ...factors (Γ0) using the tight Liso-Ep-Γ0 correlation. The statistical properties and pair correlations of the temporal and spectral parameters are studied in the observer frame, rest frame, and comoving frame, respectively. We find that the distributions of the duration, peak energy, isotropic energy, and luminosity in the different frames are basically log-normal, and that their distributions in the comoving frame are narrow, clustering around ∼ 4000 s, ∼ 0.7 keV, ∼ 8 × 1049 erg, and ∼ 2.5 × 1046 erg s−1, where the redshift evolution effect has been taken into account. We also find that the values of Γ0 are broadly distributed between a few tens and several hundreds, with median values of ∼270. We further analyze the pair correlations of all the quantities, confirm the Eiso-Ep, Liso-Ep, Liso-Γ0, and Eiso-Γ0 relations, and find that the corresponding relations in the comoving frame do still exist, but with large dispersions. This suggests not only that the well-known spectrum-energy relations are intrinsic correlations, but also that the observed correlations are governed by the Doppler effect. In addition, the peak energies of long GRBs are independent of duration both in the rest frame and in the comoving frame, and there is a weak anticorrelation between the peak energy and Lorentz factor.
Loneliness has been found to predict a wide range of physical and mental health problems. It is suggested that China's One‐Child Policy places young Chinese people at a particularly high risk for ...loneliness. Although loneliness is most prevalent in late adolescence and early adulthood, interventions have primarily targeted children or older adults with limited success. The current study examines a pilot randomized controlled trial of a mindfulness training program among Chinese college students. Participants with elevated loneliness (N = 50, ages 17–25) were randomized into either an 8‐week mindfulness training or a control group. Self‐reported measures of loneliness and mindfulness were administered at baseline and posttest. The training group also completed a program evaluation form and a 3‐month follow‐up assessment. Results provided preliminary evidence indicating that the intervention was feasible and effective at reducing loneliness among Chinese college students. Limitations and future directions were discussed.
Abstract
The intrinsic statistical properties and correlations of short gamma-ray bursts (SGRBs) have not been fully determined, due to the limitations of observations. In this paper, we compile a ...more extensive sample of 82 SGRBs with measured redshifts and present a comprehensive study of their intrinsic characteristics. We obtain the median values of the intrinsic duration (
T
90,z
), peak energy (
E
p,z
), isotropic energy (
E
iso
), and peak luminosity (
L
iso
) as 0.47 s, 466 keV, 8.21 ×10
50
erg, and 3.22 × 10
51
erg s
−1
, respectively. We update the spectrum–energy correlations, and report
E
p
,
z
∝
E
iso
0.36
±
0.05
and
E
p
,
z
∝
L
iso
0.33
±
0.04
, which further confirm the previous results that the
E
p,z
–
E
iso
correlations of SGRBs and long gamma-ray bursts (LGRBs) are different and that this correlation can be used to distinguish GRB types. We report for the first time that there is a tighter correlation between the isotropic energy of the prompt emission of SGRBs and the star formation rate of their host galaxies, which reads
sSFR
∝
E
iso
0.38
±
0.11
. Using the measured jet break time (
t
jet
) of 11 SGRBs, we tentatively investigate the
E
iso
–
E
p,z
–
t
jet,z
and
L
iso
–
E
p,z
–
t
jet,z
correlations of SGRBs and find that three-parameter correlations of SGRBs also exist and are different from those of LGRBs. Based on the
E
iso
–
E
p,z
–
t
jet,z
correlation, we estimate the
t
jet,z
values of other SGRBs and calculate the opening angles of SGRBs. We find that the median value of the SGRB opening angle is 7.°5, which is larger than that of LGRBs.
•Passive films were separated from glassy substrates as large-area thin membranes.•The highly homogeneous passive films exhibited a single-layer amorphous structure.•Main components of the passive ...films for the Ti-based MGs were TiO2, ZrO2 and BeO.•Alloying Fe and Ni contributed to the enrichment of TiO2 in the passive film.•Addition of Ni facilitated to improve the structural compactness of passive film.
Resolving structural and componential characteristics of passive film is a long-standing challenge in corrosion science since it’s difficult to separate extremely thin passive films. In this work, the passive films are successfully separated from Ti-Zr-Be-Al/Ni/Fe glassy substrates as large-area thin membranes by the designed “Ribbon-Penetration” method. The homogeneous and continuous passive films are identified as a single-layer amorphous structure, whose primary components are TiO2, ZrO2 and BeO. Alloying Ni or Fe element could induce the enrichment of TiO2 in the passive films and improve the structural compactness, resulting in the superior corrosion resistance in 3.5 wt.% NaCl solution.
Schisandra Fructus (SF) is a traditional Chinese herb used in the treatment of inflammatory disorders like hepatitis. One of the main anti-inflammatory components of SF is the lignans. However, the ...underlying anti-inflammatory mechanism of
lignans (SCL) remains unclear. This study aims to investigate the effects of SCL on inflammatory mediators in lipopolysaccharide-stimulated RAW264.7 cells and explore the underlying mechanism. The production of nitric oxide (NO) was determined by Griess reaction. ELISA was used to determine cytokine levels and chemokines secretion. To estimate protein levels and enzyme activities, we employed Western blotting. Nuclear localization of NF-κB, AP-1, and IRF3 was detected using immunofluorescence analyses. The results showed that SCL significantly reduced the release of inflammatory mediators, including NO and PGE2, which may be related to down-regulation of iNOS and COX-2 expression. The production of cytokines and chemokines was suppressed by SCL treatment. SCL also decreased the phosphorylation of IKKα/β, IκB-α, Akt, TBK1, ERK, p38, JNK, NF-κB (p65), AP-1 (c-Jun), and IRF3 in RAW264.7 macrophages activated with LPS. The nuclear protein levels and nuclear translocation of AP-1, NF-κB and IRF3 were suppressed by SCL. These results indicated that SCL suppressed the IKKα/β/NF-κB, MAPKs/AP-1 and TBK1/IRF3 signaling pathways in LPS-stimulated RAW264.7 macrophages.
Background
Restoration of HBV-specific T cell immunity is a promising approach for the functional cure of chronic Hepatitis B (CHB), necessitating the development of valid assays to boost and monitor ...HBV-specific T cell responses in patients with CHB.
Methods
We analyzed hepatitis B virus (HBV) core- and envelope (env)-specific T cell responses using in vitro expanded peripheral blood mononuclear cells (PBMCs) from patients with CHB exhibiting different immunological phases, including immune tolerance (IT), immune activation (IA), inactive carrier (IC), and HBeAg-negative hepatitis (ENEG). Additionally, we evaluated the effects of metabolic interventions, including mitochondria-targeted antioxidants (MTA), polyphenolic compounds, and ACAT inhibitors (iACAT), on HBV-specific T-cell functionality.
Results
We found that HBV core- and env-specific T cell responses were finely coordinated and more profound in IC and ENEG than in the IT and IA stages. HBV env-specific T cells were more dysfunctional but prone to respond to metabolic interventions using MTA, iACAT, and polyphenolic compounds than HBV core-specific T-cells. The responsiveness of HBV env-specific T cells to metabolic interventions can be predicted by the eosinophil (EO) count and the coefficient of variation of red blood cell distribution width (RDW-CV).
Conclusion
These findings may provide valuable information for metabolically invigorating HBV-specific T-cells to treat CHB.
Graphical abstract
Potassium-ion batteries (KIBs) are one of the most promising large-scale electric energy storage systems due to the high abundance and low redox potential of K. As the key component, anode determines ...their energy density and safety. Alloy-based anodes, such as P, Sn, Sb, and Bi, have attracted extensive attention due to their abundant resources, suitable working potentials, and large theoretical capacities. However, the dramatic volume variation upon (de)potassiation results in pulverization of particles and their detaching from the current collector accompanied with performance decay. Various strategies, including designing micro-/nanostructures, introducing carbon substrates, and optimizing electrode/electrolyte interface, have been demonstrated to effectively alleviate these issues. Herein, we summarize the recent research progresses on alloy-based materials in KIBs. The synthesis methods, electrochemical performance, reaction mechanisms, and structure–activity relationships of these materials are considered, and challenges and perspectives are provided. This review provides new insight into designing of high-activity electrode materials for KIBs and beyond.
Graphic abstract
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