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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