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Abstract The superconductivity in systems containing dispersionless (flat) bands is seemingly paradoxical, as traditional Bardeen-Cooper-Schrieffer theory requires an infinite enhancement of the carrier masses. However, the combination of flat and steep (dispersive) bands within the multiple band scenario might boost superconducting responses, potentially explaining high-temperature superconductivity in cuprates and metal hydrides. Here, we report on the magnetic penetration depths, the upper critical field, and the specific heat measurements, together with the first-principles calculations for the Mo5Si3−x P x superconducting family. The band structure features a flat band that gradually approaches the Fermi level as a function of phosphorus doping x, reaching the Fermi level at x ≃ 1.3. This leads to an abrupt change in nearly all superconducting quantities. The superfluid density data placed on the ’Uemura plot‘ results in two separated branches, thus indicating that the emergence of a flat band enhances correlations between conducting electrons.

Total factor productivity is not only the core of high-quality economic development but also a core indicator for measuring the quality of economic development. Improving total factor productivity is one of the most critical points in building a modern economic system. Firstly, this paper uses the DEA-Malmquist index method to measure and decompose the total factor productivity of China’s 30 provinces, municipalities, and autonomous regions from 2001 to 2017 and analyzes the characteristics of its temporal and spatial changes. From a spatial perspective, the regional gap is relatively large. Secondly, we construct the index system of five dimensions and use this index system to comprehensively evaluate the improvement degree of China’s modernized economic system. The results show that the overall level of the improvement degree of China’s modernized economic system is relatively low, and the differences between provinces are great. Thirdly, this paper uses static and dynamic spatial econometric models to empirically analyze the effect of total factor productivity on the improvement degree of the modern economic system. The results show that the improvement degree of the modern economic system in China has obvious characteristics of time spillover and space spillover. Finally, we put forward countermeasures and suggestions on how to perfect the modern economic system.

We report the synthesis and characterization of a new ternary molybdenum pnictide superconductor, Cs2Mo3As3. The powder x-ray diffraction analysis reveals the quasi-one-dimensional (Q1D) hexagonal crystal structure formed by Cs+ and infinite (Mo3As3)2− chains as indicated by the wire-like grain morphology. Electrical resistivity and magnetic susceptibility characterizations exhibit superconductivity with the onset transition temperature at 11.5 K, which is the highest in all Q1D superconductors reported so far. An upper critical magnetic field of about 61.7 T at zero temperature was extrapolated from the resistivity measurement under a magnetic field, which is much higher than the Pauli paramagnetic limit, and the reason for such a high upper critical field may lie in its unconventional nature of superconducting pairing symmetry. The discovery of Cs2Mo3As3 inspires the search for new superconductors for future high field applications.

The reaction of [(3-bdppmapy)(AuCl)2] with NaHmna (3-bdppmapy = N,N’-bis-(diphenylphosphanylmethyl-3-aminopytidine, H2mna = 2-mercaptonicotinic acid)) resulted in a tetranuclear Au-P-S complex [(3-bdppmapy)2(AuHmna)2(AuCl)2] (1) which emitted bright yellow fluorescence at 542 nm under 377 nm excitation (QY = 5.3%, τ = 0.83 ns). Upon grinding, the emission intensity of 1 significantly and rapidly decreased, but could be recovered by exposure to CH2Cl2 vapor. This switchable fluorescence is attributed to the breaking and reforming of intermolecular hydrogen bonds with concomitant collapse and the restoration of the crystalline phase, which is not caused by static pressure or increased temperature.

Abstract A stable { $$\stackrel{\mathrm{-}}{1}{\text{10}}$$ 1 - 10 } single component sharp texture was obtained during ambient temperature tube High-Pressure Shearing (t-HPS) of 99.999% purity aluminum. It is shown that the grain size and the grain aspect ratio saturate at ~ 8 μm and ~ 1.6, respectively, at an equivalent strain of ~ 30 and the high-angle grain boundary fraction continues to decrease after this saturation even to equivalent strains exceeding ~ 200. The { $$\stackrel{\mathrm{-}}{1}{\text{10}}$$ 1 - 10 } texture emerges at an equivalent strain of ~ 6 to 9 with the completion of recrystallization and develops gradually as a sole component sharp texture with increasing intensity upon further processing. This component is a stable orientation in t-HPS processing although it was not previously observed experimentally as a shear texture. Thus, t-HPS processing provides a new and effective experimental tool for simple shear testing that is distinctly different from earlier shear strain methods such as torsional processing.

Full-waveform inversion (FWI) uses the full information of seismic data to obtain a quantitative estimation of subsurface physical parameters. Anisotropic FWI has the potential to recover high-resolution velocity and anisotropy parameter models, which are critical for imaging the long-offset and wideazimuth data. We develop an acoustic anisotropic FWI method based on a simplified pure quasi Pwave (qP-wave) equation, which can be solved efficiently and is beneficial for the subsequent inversion. Using the inverse Hessian operator to precondition the functional gradients helps to reduce the parameter tradeoff in the multi-parameter inversion. To balance the accuracy and efficiency, we extend the truncated Gauss-Newton (TGN) method into FWI of pure qP-waves in vertical transverse isotropic (VTI) media. The inversion is performed in a nested way: a linear inner loop and a nonlinear outer loop. We derive the formulation of Hessian-vector products for pure qP-waves in VTI media based on the Lagrange multiplier method and compute the model update by solving a Gauss-Newton linear system via a matrix-free conjugate gradient method. A suitable preconditioner and the Eisenstat and Walker stopping criterion for the inner iterations are used to accelerate the convergence and avoid prohibitive computational cost. We test the proposed FWI method on several synthetic data sets. Inversion results reveal that the pure acoustic VTI FWI exhibits greater accuracy than the conventional pseudoacoustic VTI FWI. Additionally, the TGN method proves effective in mitigating the parameter crosstalk and increasing the accuracy of anisotropy parameters. [ABSTRACT FROM AUTHOR]

In the fields of optics and photonics, phase-only spatial light modulators (SLMs) play an increasingly important role in wave-front engineering. However, the SLMs are subject to wavefront distortion arising from the imperfection in the birefringence effect and physical structure of modulators. This paper presents a simple self-interference phase calibration method applicable to liquid-crystal SLM. We build an interferometric imaging system based on the Pancharatnam phase-shifting to measure the phase distribution of a light beam coming from SLMs. Two types of phase modulation errors of SLMs can be characterized in the measurement process: the erroneous gamma curve and shape aberration. The former belongs to dynamic phase distortion and is measured through a four-step Pancharatnam phase-shifting interference, which allows a one-shot recording of interference pattern via a polarization camera; the latter represents static phase distortion and is extracted from the interference between light waves coming from different regions of the SLM panel by using Zernike polynomial fitting. Our method has the advantages of high-precision pixel-wise phase correction and robustness against environmental disturbance and thus can facilitate the applications of SLM in optical field manipulation.

Introduction Lung cancer was the most common malignancy and the leading cause of cancer-related death in China or worldwide, and surgery is still the preferred treatment for early-stage non-small cell lung cancer (NSCLC). The pattern of lymph node metastasis was found potentially lobe specific, and thus, lobe-specific lymph node dissection (L-SLND) was proposed to be an alternative to systematic lymph node dissection (SLND) for the treatment of early-stage NSCLC.Methods and analysis The LobE-Specific lymph node diSsectiON trial is a single-institutional, randomised, double-blind and parallel controlled trial to investigate the feasibility of L-SLND in clinically diagnosed stage IA1-2 NSCLC with ground-glass opacity components (≥50%). The intraoperative frozen section examination of surgical tissues confirms the histological type of NSCLC. We hypothesise that L-SLND (experimental group) is not inferior to SLND (control group) and intend to include 672 participants for the experimental group and 672 participants for the control group with a follow-up duration of 60 months. The primary outcomes are 5-year disease-free survival and 5-year overall survival. The secondary outcomes are metastatic lymph node ratio, postoperative complication incidence and mortality, duration of operation, duration of anaesthesia (min), the volume of bleeding (mL) and drainage volume. The intention-to-treat analysis would be performed in the trial.Ethics and dissemination This trial was approved by the ethics committee on biomedical research, West China Hospital of Sichuan University (2021-332). Informed consent would be obtained from all participants, and dissemination activities would include academic conference presentations and peer-reviewed publications.Trial registration number This trial was registered in the Chinese Clinical Trial Registry, ChiCTR2100048415.

Objective: The human microbiota plays a key role in cancer diagnosis, pathogenesis, and treatment. However, osteosarcoma-associated oral microbiota alterations have not yet been unraveled. The aim of this study was to explore the characteristics of oral microbiota in osteosarcoma patients compared to healthy controls, and to identify potential microbiota as a diagnostic tool for osteosarcoma. Methods: The oral microbiota was analyzed in osteosarcoma patients (n = 45) and matched healthy controls (n = 90) using 16S rRNA MiSeq sequencing technology. Results: The microbial richness and diversity of the tongue coat were increased in osteosarcoma patients as estimated by the abundance-based coverage estimator indices, the Chao, and observed operational taxonomy units (OTUs). Principal component analysis delineated that the oral microbial community was significant differences between osteosarcoma patients and healthy controls. 14 genera including Rothia, Halomonas, Rhodococcus, and Granulicatella were remarkably reduced, whereas Alloprevotella, Prevotella, Selenomonas, and Campylobacter were enriched in osteosarcoma. Eventually, the optimal four OTUs were identified to construct a microbial classifier by the random forest model via a fivefold cross-validation, which achieved an area under the curve of 99.44% in the training group (30 osteosarcoma patients versus 60 healthy controls) and 87.33% in the test group (15 osteosarcoma patients versus 30 healthy controls), respectively. Notably, oral microbial markers validated strong diagnostic potential distinguishing osteosarcoma patients from healthy controls. Conclusion: This study comprehensively characterizes the oral microbiota in osteosarcoma and reveals the potential efficacy of oral microbiota-targeted biomarkers as a noninvasive biological diagnostic tool for osteosarcoma. [ABSTRACT FROM AUTHOR]

Recognized in the 1990s, vortex beams' ability to carry orbital angular momentum (OAM) has significantly contributed to applications in optical manipulation and high-dimensional classical and quantum information communication. However, inherent diffraction in free space results in the inevitable expansion of beam size and divergence contingent upon the OAM, limiting vortex beams' applicability in areas such as spatial mode multiplexing communication, fiber-optic data transmission, and particle manipulation. These domains necessitate vortex beams with OAM-independent propagation characteristics. We introduce iso-propagation vortices (IPVs), vortex beams characterized by OAM-independent propagation behavior, achieved through precise radial index configuration of Laguerre-Gaussian beams. IPVs display notable transmission dynamics, including a reduced quality factor, resilience post-damage, and decreased and uniform modal scattering under atmospheric turbulence. Their distinctive attributes render IPVs valuable for potential applications in imaging, microscopy, optical communication, metrology, quantum information processing, and light-matter interactions. Notably, within optical communication, the case study suggests that the IPV basis, due to its OAM-independent propagation behavior, provides access to a more extensive spectrum of data channels compared with conventional spatial multiplexing techniques, consequently augmenting information capacity. [ABSTRACT FROM AUTHOR]

Blastocystis is a common enteric protist that colonizes humans and a wide range of animals. Although some studies have reported incidences of Blastocystis in humans and animals in China, there is no information available on the prevalence of Blastocystis in giant pandas, red pandas, or bird species. The aims of the present study were to determine the prevalence, subtype distribution, and genetic characterizations of Blastocystis in these animals in a captive situation in southwestern China, as well as assess the zoonotic potential of Blastocystis isolates. A total of 168 fecal specimens, including 81 from giant pandas, 23 from red pandas, 38 from black swans, 11 from ruddy shelducks, and 15 from green peafowl were collected at the Chengdu Research Base of Giant Panda Breeding in Sichuan province. The overall minimum prevalence of Blastocystis was 11.3% (19/168) based on PCR amplification of the barcode region of the SSU rRNA gene. The highest prevalence of Blastocystis was observed in ruddy shelduck (18.2%) and the lowest was found in green peafowl (6.7%). The prevalence of Blastocystis in giant pandas >5.5 years of age was higher than that in younger giant pandas. Two potentially zoonotic subtypes (ST1 and ST8) were identified, and ST1 (n = 12) was found to be more prevalent than ST8 (n = 7). To the best of our knowledge, this is the first report of the prevalence and subtypes of Blastocystis in giant pandas, red pandas, and bird species in China. The findings of this study will improve our understanding of the genetic diversity and public health potential of Blastocystis. Keywords: Blastocystis, Pandas, Genetic diversity, Zoonotic potential, China

Background and aims: Dementia imposes a heavy burden on society and families, therefore, effective drug treatments, exploring and preventing factors associated with dementia, are paramount. To provide reference points for the best frequency of physical exercise (physical exercise), we investigated the association between frequency of PE and cognition in Chinese old adults. Methods: 16,181 Chinese participants aged 65  years or older were included in this study. Associations between PE and cognition were estimated multivariate logistic and linear regression analyses. Associations were further investigated across dementia subtypes (Alzheimer dementia, vascular dementia, and other types of dementia). Subgroup analyses were performed in different age groups, in populations with and without stroke, and those with and without hypertension. Results: PE associated with dementia after adjusting for full covariates (OR: 0.5414, 95% CI: 0.4536–0.6491, p  <  0.001). Exercise performed at ≥3 times/ week associated with lower risk of dementia (OR: 0.4794–0.6619, all p value <0.001). PE was associated with improved cognition (β: 12851, p  <  0.001), and any PE frequency contributed to cognitive improvement (p values for exercise performed ≥1 time/week were <0.001). Similar conclusions were identified when we repeated analyses in different dementia subtypes and age groups. Subgroup analyses suggested that the cognition of individuals without hypertension also benefitted from exercising 1–2 times/week (OR: 0.6168, 95% CI: 0.4379–0.8668, p  =  0.005). Conclusion: The best exercise frequency is exercising ≥3 times/week for individuals from different dementia subtypes and age groups. While for those without hypertension, PE at 1–2 times /week is also beneficial. [ABSTRACT FROM AUTHOR]

Brief-pulse stimulation at 50 Hz has been shown to terminate afterdischarges observed in epilepsy patients. However, the optimal pulse stimulation parameters for terminating cortical electrical stimulation-induced afterdischarges remain unclear. In the present study, we examined the effects of different brief-pulse stimulation frequencies (5, 50 and 100 Hz) on cortical electrical stimulation-induced afterdischarges in 10 patients with refractory epilepsy. Results demonstrated that brief-pulse stimulation could terminate cortical electrical stimulation-induced afterdischarges in refractory epilepsy patients. In conclusion, (1) a brief-pulse stimulation was more effective when the afterdischarge did not extend to the surrounding brain area. (2) A higher brief-pulse stimulation frequency (especially 100 Hz) was more likely to terminate an afterdischarge. (3) A low current intensity of brief-pulse stimulation was more likely to terminate an afterdischarge

Entangled porous metallic wire material (EPMWM) has the potential as a thermal insulation material in defence and engineering. In order to optimize its thermophysical properties at the design stage, it is of great significance to reveal the thermal response mechanism of EPMWM based on its complex structural effects. In the present work, virtual manufacturing technology (VMT) was developed to restore the physics-based 3D model of EPMWM. On this basis, the transient thermal analysis is carried out to explore the contact-relevant thermal behavior of EPMWM, and then the spiral unit containing unique structural information are further extracted and counted. In particular, the thermal resistance network is numerically constructed based on the spiral unit through the thermoelectric analogy method to accurately predict the effective thermal conductivity (ETC) of EPMWM. Finally, the thermal diffusivity and specific heat of the samples were obtained by the laser thermal analyzer to calculate the ETC and thermal insulation factor of interest. The results show that the ETC of EPMWM increases with increasing temperature or reducing density under the experimental conditions. The numerical prediction is consistent with the experimental result and the average error is less than 4%. [ABSTRACT FROM AUTHOR]

Research on seismic anisotropy and attenuation plays a significant role in exploration geophysics. To enhance the imaging quality for complicated structures, we develop several effective improvements for anisotropic attenuation effects in reverse-time migration (Q-RTM) on surface and vertical seismic profiling (VSP) acquisition geometries. First, to suppress pseudo-shear wave artifact and numerical instability of the commonly used anisotropic pseudo-acoustic wave equations, an optimized pure P-wave dispersion relation is derived and the corresponding pure-mode wave equation is solved by combining the finite-difference and Possion methods. Second, a simplified anisotropic pure-mode visco-acoustic wave equation (PVAWE) based on standard linear solid model is established. Third, a time-dispersion correlation strategy is applied to improve the modeling accuracy. Fourth, we extend a target-oriented scheme to anisotropic attenuated modeling and imaging. Instead of the conventional wavefield modeling and RTM, the proposed approach can extract available wavefield information near the target regions and produce high imaging resolution for target structures. Last, both anisotropic surface and VSP Q-RTMs are executed by combining optimized PVAWE, time-dispersion correlation and target-oriented algorithm. Modeling examples demonstrate the advantages of our schemes. Moreover, our modified Q-compensated imaging workflow can be regarded as a supplement to the classical anisotropic RTM. [ABSTRACT FROM AUTHOR]

Composite materials exhibit the impressive mechanical properties of high damping and stiffness, which cannot be attained by employing conventional single materials. Along these lines, a novel material architecture is presented in this work in order to fabricate composites with enhanced mechanical characteristics. More specifically, entangled metallic wire materials were used as the active matrix, whereas polyurethane was employed as the reinforcement elements. As a result, an entangled metallic wire material-polyurethane composite with high damping and stiffness was prepared by enforcing the vacuum infiltration method. On top of that, the mechanical properties (loss factor, energy consumption, and average stiffness) of the proposed composite materials were characterized by performing dynamic tests, and its fatigue characteristics were verified by the micro-interface bonding, as well as the macro-damage factor. The impact of the density, preloading spacing, loading amplitude, and exciting frequency on the mechanical properties of the composites were also thoroughly analyzed. The extracted results indicate that the mechanical properties of the composites were significantly enhanced than those of the pure materials due to the introduction of interface friction. Moreover, the average stiffness of the composites was about 10 times the respective value of the entangled metallic wire material. Interestingly, a rise in the loading period leads to some failure between the composite interfaces, which reduces the stiffness property but enhances the damping dissipation properties. Finally, a comprehensive dynamic mechanical model of the composites was established, while it was experimentally verified. The proposed composites possess higher damping features, i.e., stiffness characteristics, and maintain better fatigue characteristics, which can broaden the application range of the composites. In addition, we provide a theoretical and experimental framework for the research and applications in the field of metal matrix composites. [ABSTRACT FROM AUTHOR]

Objective: To observe the early changes in peripheral blood cytokine levels after treatment of metastatic hepatic carcinoma (MHC) with CalliSpheres microspheres drug-eluting beads (DEB) transcatheter arterial chemoembolization (CSM-TACE). Methods: Twenty-eight patients with refractory MHC who underwent CSM-TACE were selected prospectively, and 5mL of peripheral blood was collected before CSM-TACE and on the 2nd and 5th day after CSM-TACE. Flow cytometry was used to detect immunological indicators. The early changes in levels of peripheral blood cell inflammatory factors Th1 (interleukin 2 (IL-2), tumor necrosis factor-a (TNF-a), interferon (IFN-r)), Th2 (IL-4, IL-6, IL-10), and Th17 (IL-17A) were observed after CSM-TACE, as well as the ratio of CD4+/CD8+. Results: All the 28 patients underwent CSM-TACE successfully. CT at 4 days after CSM-TACE showed clear outline low-density changes in liver tumors, and honeycomb necrosis was observed in the tumors in some cases. After CSM-TACE, the IL-6 and IL-10 levels were increased and then decreased again. After CSM-TACE, IL-2 showed a trend of transient increase and then decreased again, and the TNF-a level decreased temporarily, and then decreased. After CSM-TACE, the IFN-r level showed a continuous and slowly increasing trend. The IL-17 level showed a continuous downward trend, and the CD4+/CD8+ ratio showed a gradual and continuous upward trend, and there was a negative correlation between them. Conclusions: There are complex dynamic changes in TH1/Th2 in the early stage of CSM-TACE, and the acute inflammatory response and the enhancement of the body's immune anti-tumor response coexist. [ABSTRACT FROM AUTHOR]

Mutations in serologically defined colon cancer autoantigen protein 8 (SDCCAG8) were first identified in retinal ciliopathy families a decade ago with unknown function. To investigate the pathogenesis of SDCCAG8-associated retinal ciliopathies in vivo, we employed CRISPR/Cas9- mediated homology-directed recombination (HDR) to generate two knock-in mouse models, Sdccag8Y236X/Y236X and Sdccag8E451GfsX467/E451GfsX467, which carry truncating mutations of the mouse Sdccag8, corresponding to mutations that cause Bardet-Biedl syndrome (BBS) and Senior-Løken syndrome (SLS) (c.696T>G p.Y232X and c.1339–1340insG p.E447GfsX463) in humans, respectively. The two mutant Sdccag8 knock-in mice faithfully recapitulated human SDCCAG8-associated BBS phenotypes such as rod-cone dystrophy, cystic renal disorder, polydactyly, infertility, and growth retardation, with varied age of onset and severity depending on the hypomorphic strength of the Sdccag8 mutations. To the best of our knowledge, these knock-in mouse lines are the first BBS mouse models to present with the polydactyly phenotype. Major phototransduction protein mislocalization was also observed outside the outer segment after initiation of photoreceptor degeneration. Impaired cilia were observed in the mutant photoreceptors, renal epithelial cells, and mouse embryonic fibroblasts derived from the knock-in mouse embryos, suggesting that SDCCAG8 plays an essential role in ciliogenesis, and cilium defects are a primary driving force of SDCCAG8-associated retinal ciliopathies. [ABSTRACT FROM AUTHOR]

An unprecedented pentanuclear lanthanum thiolate oxide complex is isolated as a result of the adventitious water but is regenerated in an acceptable yield through control of hydrolysis. This synthetic strategy can be used in the preparation of other new oxolanthanide thiolate complexes with better catalytic performances.