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Graphyne has recently attracted much attention since it is an important derivative of graphene with unique topological properties. Although graphyne is not a conventional topological insulator because of its weak spin–orbit coupling, it is a real Chern topological insulator with the higher-order topology. However, it lacks a realistic model. Here, we propose a schedule to realize acoustic graphyne. By introducing negative coupling to simulate the carbon–carbon triple bond, we realize the transition from trivial to higher-order topological phases, characterized by real Chern numbers. These topologically protected corner states are achieved in a finite-size sample, and the condition for their existence is discussed. Our research extends the concept of real Chern insulators and provides a platform for studying the topological properties of graphene-like structural compounds. [ABSTRACT FROM AUTHOR]

Fructus Tribuli (FT), a traditional Chinese medicinal herbal, has been used for the clinical treatment of cardiovascular diseases for many years and affects vascular endothelial dysfunction (ED) in patients with hypertension. This study aimed to demonstrate the pharmacodynamic basis and mechanisms of FT for the treatment of ED. The present study used ultra-high-performance liquid chromatography coupled with quadruple-time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) to analyze and identify the chemical components of FT. The active components in blood were determined after the oral administration of FT by comparative analysis to blank plasma. Then, based on the active components in vivo , network pharmacology was performed to predict the potential targets of FT in treating ED. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were also performed, and component-target-pathway networks were constructed. Interactions between the major active components and main targets were verified by molecular docking. Moreover, spontaneously hypertensive rats (SHRs) were divided into the normal, model, valsartan, low-dose FT, medium-dose FT, and high-dose FT experimental groups. In pharmacodynamic verification studies, treatment effects on blood pressure, serum markers (nitric oxide [NO], endothelin-1 [ET-1,], and angiotensin Ⅱ [Ang Ⅱ)]) of ED, and endothelial morphology of the thoracic aorta were evaluated and compared between groups. Finally, the PI3K/AKT/eNOS pathway was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot of the thoracic aorta of rats in each group to detect the mRNA expression of PI3K, AKT, and eNOS and the protein expression of PI3K, AKT, p-AKT, eNOS, and p-eNOS. A total of 51 chemical components were identified in FT, and 49 active components were identified in rat plasma. Thirteen major active components, 22 main targets, and the PI3K/AKT signaling pathway were screened by network pharmacology. The animal experiment results showed that FT reduced systolic blood pressure and ET-1 and Ang Ⅱ levels and increased NO levels in SHRs to varying degrees. The therapeutic effects were positively correlated with the oral dose of FT. Hematoxylin-eosin (HE) staining confirmed that FT could alleviate the pathological damage of the vascular endothelium. qRT-PCR and Western blot analysis confirmed that up-regulated expression of the PI3K/AKT/eNOS signaling pathway could improve ED. In this study, the material basis of FT was comprehensively identified, and the protective effect on ED was confirmed. FT had a treatment effect on ED through multi-component, multi-target, and multi-pathways. It also played a role by up-regulating the PI3K/AKT/eNOS signaling pathway. [Display omitted] • An effective approach combining UHPLC-Q/TOF-MS analysis with network pharmacology and experimental verification was applied. • The material basis of Fructus Tribuli were comprehensively identified. • Fructus Tribuli has the treatment effect on endothelial dysfunction by up-regulating PI3K/AKT/eNOS signaling pathway. [ABSTRACT FROM AUTHOR]

This paper considers a stochastic multi-period inventory and acquisition effort decisions problem in a hybrid manufacturing/remanufacturing system. Different from past papers, two factors are introduced into the dynamic decision problem. One is the dependency between sales and returns, the other is the dual impacts of acquisition effort on the return of used products and the demand. Few past papers consider them, but they are important and unavoidable for many practical cases. These factors make the problem a high-dimensional decision-making problem, which is difficult to analyze and solve the optimal policy by stochastic dynamic programming, so we employ the robust optimization method. Based on the duality theory, an equivalent robust optimization model is given, which is a convex programming problem. By numerical analyses, we analyze the effects of system parameters on the related decisions and profits, which can provide insights for producers to manage their hybrid manufacturing/remanufacturing systems. [ABSTRACT FROM AUTHOR]

Due to the performance degradation of liner systems, landfill leachate may significantly increase over the long term, and ignorance of this may lead to a serious underestimation of a landfill's emissions and associated environmental impact during its life cycle. This paper examined the long-term behavior of HDPE geomembranes under field conditions using analytical and mechanical tests as well as the geoelectric leak location method. The aging information obtained, together with site-specific meteorological and hydrogeological data and landfill design parameters, were then used in the LandSim and HELP models to perform quantitative analyses of leachate production, emission, and environmental impacts on groundwater. The results demonstrated that the HDPE geomembranes reaches its service life after 8 years of landfill operation, beyond which its hydraulic performance begins to degrade rapidly. This results in leachate leakage increasing from an initial level of 0.05–0.6 m3/d to a long-term range of 27.4–37.6 m3/d. This is accompanied by changes to its impact on groundwater, with the impact extent expanding from 50 to 1000 m and pollution probability going from "almost impossible" to "almost certain". The above results remind us to take measures to control the aging process of HDPE geomembranes in landfill environments in order to extend their service life. Moreover, it also suggests that we should consider the long-term emissions of landfills as well as the impact of secondary waste disposal when conducting landfill life cycle assessment. • HDPE GM life in filed condition is 10–300 times shorter than that expected ideally. • Results in a drastic increase in leachate leakage from 0.05 to 0.6 to 27.4–37.6 m3/d. • Indicates emissions in its EOL accounting for a large proportion in its life cycle. [ABSTRACT FROM AUTHOR]

The topological phase of matter, originally proposed and first demonstrated in fermionic electronic systems, has drawn considerable research attention in the past decades due to its robust transport of edge states and its potential with respect to future quantum information, communication, and computation. Recently, searching for such a unique material phase in bosonic systems has become a hot research topic worldwide. So far, many bosonic topological models and methods for realizing them have been discovered in photonic systems, acoustic systems, mechanical systems, etc. These discoveries have certainly yielded vast opportunities in designing material phases and related properties in the topological domain. In this review, we first focus on some of the representative photonic topological models and employ the underlying Dirac model to analyze the edge states and geometric phase. On the basis of these models, three common types of two-dimensional topological photonic systems are discussed: 1) photonic quantum Hall effect with broken time-reversal symmetry; 2) photonic topological insulator and the associated pseudo-time-reversal symmetry-protected mechanism; 3) time/space periodically modulated photonic Floquet topological insulator. Finally, we provide a summary and extension of this emerging field, including a brief introduction to the Weyl point in three-dimensional systems. [ABSTRACT FROM AUTHOR]

The recent discovery of anti‐chiral edge states in magnetic semimetals linking two unequal‐frequency bulk Dirac nodes manifests a paradoxical picture in contrast to the chiral behavior in Chern insulators, implying an untapped phase may exist. Here, a unique Chern metal, exhibiting a nontrivial Chern number but without a complete bandgap is proposed, and the complete topological phase diagram in the modified Haldane model is obtained. Subsequently, the Chern metal in a 2D honeycomb‐lattice gyromagnetic photonic crystal by simultaneously breaking parity and time‐reversal symmetries with opposite and unequal magnetic biases at different sublattices is realized. For the paired complementary‐shape boundaries, such as zigzag/bearded, it is experimentally revealed that either clockwise or counter‐clockwise chiral character is switchable in Chern metals relying on different boundary choices, a remarkable property deemed as bi‐chiral edge propagation. The topological Chern metal with hidden bulk‐boundary correspondence is articulated to bridge the chiral and anti‐chiral paradox gap between Chern insulators and magnetic semimetals. These results enrich the family of Chern materials and highlight the previously untapped on‐demand control of topological edge states. [ABSTRACT FROM AUTHOR]

Precise regulation of the active site structure is an important means to enhance the activity and selectivity of catalysts in CO2 electroreduction. Here, we creatively introduce anionic groups, which can not only stabilize metal sites with strong coordination ability but also have rich interactions with protons at active sites to modify the electronic structure and proton transfer process of catalysts. This strategy helps to convert CO2 into fuel chemicals at low overpotentials. As a typical example, a composite catalyst, CuO/Cu−NSO4/CN, with highly dispersed Cu(II)−SO4 sites has been reported, in which CO2 electroreduction to formate occurs at a low overpotential with a high Faradaic efficiency (−0.5 V vs. RHE, FEformate=87.4 %). Pure HCOOH is produced with an energy conversion efficiency of 44.3 % at a cell voltage of 2.8 V. Theoretical modeling demonstrates that sulfate promotes CO2 transformation into a carboxyl intermediate followed by HCOOH generation, whose mechanism is significantly different from that of the traditional process via a formate intermediate for HCOOH production. [ABSTRACT FROM AUTHOR]

Precise regulation of the active site structure is an important means to enhance the activity and selectivity of catalysts in CO2 electroreduction. Here, we creatively introduce anionic groups, which can not only stabilize metal sites with strong coordination ability but also have rich interactions with protons at active sites to modify the electronic structure and proton transfer process of catalysts. This strategy helps to convert CO2 into fuel chemicals at low overpotentials. As a typical example, a composite catalyst, CuO/Cu−NSO4/CN, with highly dispersed Cu(II)−SO4 sites has been reported, in which CO2 electroreduction to formate occurs at a low overpotential with a high Faradaic efficiency (−0.5 V vs. RHE, FEformate=87.4 %). Pure HCOOH is produced with an energy conversion efficiency of 44.3 % at a cell voltage of 2.8 V. Theoretical modeling demonstrates that sulfate promotes CO2 transformation into a carboxyl intermediate followed by HCOOH generation, whose mechanism is significantly different from that of the traditional process via a formate intermediate for HCOOH production. [ABSTRACT FROM AUTHOR]

Fructus Tribuli (FT) has been commonly used as a traditional medicine for thousands of years. With the diverse uses of FT, more attention has been paid to its hepatorenal toxicity. However, the compounds causing the hepatorenal toxicity of FT remain undetermined. Terrestrosin D (TED), a major spirostanol saponin isolated from FT, may exert hepatorenal toxicity. This study aimed to evaluate the potential hepatorenal toxicity of TED, and preliminarily explore the possible mechanism of TED-induced hepatorenal toxicity. Cytotoxicity assays, a repeated-dose 28-day in-vivo study, a toxicokinetic study, and a tissue distribution study were used to evaluate the potential hepatorenal toxicity of TED. Furthermore, network pharmacology was applied to preliminarily explore the possible mechanism of TED-induced hepatorenal toxicity. Both the in vitro and in vivo studies showed that the spirostanol saponin TED had potential hepatorenal toxicity. Nonetheless, hepatorenal toxicity induced by oral treatment with TED at a dosage range of 5 – 15 mg/kg daily for 28 consecutive days to Sprague-Dawley (SD) rats was reversible after 14 days of TED withdrawal. The toxicokinetic study demonstrated that the systematic exposure of SD rats to TED had an accumulation phenomenon and a dose-dependent trend after a 28-day repeated-dose oral administration. The tissue distribution study revealed that TED had a targeted distribution in the liver and kidneys accompanied by a phenomenon of accumulation in SD rats. Network pharmacology combined with molecular docking methods was used to screen for the key targets (HSP90AA1, CNR1, and DRD2) and the key pathways of TED-induced hepatorenal toxicity. The spirostanol saponin TED, a major spirostanol saponin isolated from FT, had potential hepatorenal toxicity. [Display omitted] [ABSTRACT FROM AUTHOR]

Waveguides and resonators are core components in the large-scale integration of electronics, photonics and phononics, both in existing and future scenarios. In certain situations, there is critical coupling of the two components; i.e. no energy passes through the waveguide after the incoming wave couples into the resonator. The transmission spectral characteristics resulting from this phenomenon are highly advantageous for signal filtering, switching, multiplexing and sensing. In the present study, adopting an elastic-wave platform, we introduce topological insulator (TI), a remarkable achievement in condensed matter physics over the past decade, into a classical waveguide-ring-resonator configuration. Along with basic similarities with classical systems, a TI system has important differences and advantages, mostly owing to the spin-momentum locked transmission states at the TI boundaries. As an example, a two-port TI waveguide resonator can fundamentally eliminate upstream reflections while completely retaining useful transmission spectral characteristics, and maximize the energy in the resonator, with possible applications being novel signal processing, gyro/sensing, lasering, energy harvesting and intense wave–matter interactions, using phonons, photons or even electrons. The present work further enhances confidence in using topological protection for practical device performance and functionalities, especially considering the crucial advantage of introducing (pseudo)spins to existing conventional configurations. More in-depth research on advancing phononics/photonics, especially on-chip, is foreseen. [ABSTRACT FROM AUTHOR]

The vacation queue models have been studied by many researchers. They usually assume that the server will take a vacation immediately at the end of a busy period. But in some cases, it is random that the server takes a vacation when the system is empty. Therefore, we study an M/G/1 queue model with random vacation policy in this paper. We derive the indexes such as the mean queue length, mean sojourn time of customers and the busy period of the server. Finally, numerical examples are provided for illustration. [ABSTRACT FROM AUTHOR]

As exotic phenomena in optics, topological states in photonic crystals have drawn much attention due to their fundamental significance and great potential applications. Because of the broken time-reversal symmetry under the influence of an external magnetic field, the photonic crystals composed of magneto-optical materials will lead to the degeneracy lifting and show particular topological characters of energy bands. The upper and lower bulk bands have nonzero integer topological numbers. The gapless edge states can be realized to connect two bulk states. This topological photonic states originated from the topological property can be analogous to the integer quantum Hall effect in an electronic system. The gapless edge state only possesses a single sign of gradient in the whole Brillouin zone, and thus the group velocity is only in one direction leading to the one-way energy flow, which is robust to disorder and impurity due to the nontrivial topological nature of the corresponding electromagnetic states. Furthermore, this one-way edge state would cross the Brillouin center with nonzero group velocity, where the negative-zero-positive phase velocity can be used to realize some interesting phenomena such as tunneling and backward phase propagation. On the other hand, under the protection of time-reversal symmetry, a pair of gapless edge states can also be constructed by using magnetic-electric coupling meta-materials, exhibiting Fermion-like spin helix topological edge states, which can be regarded as an optical counterpart of topological insulator originating from the spin-orbit coupling. The aim of this article is to have a comprehensive review of recent research literatures published in this emerging field of photonic topological phenomena. Photonic topological states and their related phenomena are presented and analyzed, including the chiral edge states, polarization dependent transportation, unidirectional waveguide and nonreciprocal optical transmission, all of which might lead to novel applications such as one-way splitter, optical isolator and delay line. In addition, the possible prospect and development of related topics are also discussed. [ABSTRACT FROM AUTHOR]

Background: Cancer-testis antigens (CTAs) are suitable targets for cancer-specific immunotherapy. The aim of the study is to investigate the expression of CTAs in intrahepatic cholagiocarcinoma (IHCC) and evaluate their potential therapeutic values. Methods: Eighty-nine IHCC patients were retrospectively assessed for their expression of CTAs and HLA Class I by immunohistochemistry using the following antibodies: MA454 recognizing MAGE-A1, 57B recognizing multiple MAGE-A (MAGE-A3/A4), E978 recognizing NY-ESO-1, and EMR8-5 recognizing HLA class I. The clinicopathological and prognostic significance of individual CTA markers and their combination were further evaluated. Results: The expression rates of MAGE-A1, MAGE-A¾ and NY-ESO-1 were 29.2%, 27.0% and 22.5%, respectively. The concomitant expression of CTAs and HLA class I antigen was observed in 33.7% of the IHCC tumors. We found that positive MAGE-¾ expression correlated with larger tumor size (≥ 5 cm), tumor recurrence and poor prognosis. Moreover, we identified 52 cases (58.4%) of IHCC patients with at least one CTA marker expression, and this subgroup displayed a higher frequency of larger tumor size and a shorter survival than the other cases. Furthermore, expression of at least one CTA marker was also an independent prognostic factor in patients with IHCC. Conclusion: Our data suggest that specific immunotherapy targeted CTAs might be a novel treatment option for IHCC patients. [ABSTRACT FROM AUTHOR]

Exploring earth‐abundant materials for low concentration CO2 photoreduction is the key in the energy related field. Here, we demonstrated biphasic titania (anatase and rutile) derived from Ti‐based metal‐organic framework (MOF) nanoplates exhibited excellent performance in CO2 photoreduction without any co‐catalysts and sacrificial agents under ambient condition, the maximum CH4 production rate was up to 65.39 μmol g−1 h−1 with near 100 % electron selectivity as well as great stability. The activity of the optimal derivative was maintained well even in 1 % CO2 (CH4: 45.59 μmol g−1 h−1) and much better than that of commercial P25. The upgraded performance originated from the synergism between local anatase/rutile interface and numerous defective sites (Ti3+ and Ov), by promoting the separation and migration of photogenerated carriers, CO2 adsorption and activation, and H2O dissociation. Besides, a possible fast hydrodeoxygenation mechanism for methane formation was proposed according to in situ DRIFTS characterization. [ABSTRACT FROM AUTHOR]

A constitutive model is constructed to consider the resin matrix post-yield softening and progressive hardening behaviors. A user-defined material mechanical behavior (UMAT) subroutine is created, then the non-linear three-dimensional finite element analysis on the tensile processes of multi-fiber composites is conducted. The approximate 45° shear bands emanating from the matrix crack tip are found, being coincided with the experimental observations. The shear stress on the adjacent intact fiber/matrix interface is strongly influenced by the shear band and thus the stress concentration factor (SCF) changes obviously in the adjacent fibers. The distinct stress redistribution in the adjacent intact fibers implies the significant effect of the shear bands on the progressive fiber fracture initiation. As the inter-fiber spacing increases, the peak value of the SCF in the adjacent intact fiber decreases, whereas the overload zone becomes wider. The research has provided a helpful tool to evaluate the failure of fiber composites and optimize the composite performance through the proper selection of resin matrix properties and fiber volume fraction. [ABSTRACT FROM AUTHOR]

This paper introduces a new method for the early detection of gastric cancer using a combination of feature extraction based on discrete wavelet transformation (DWT) for horizontal attenuated total reflectance-Fourier transform infrared spectroscopy (HATR-FT-IR) and classification using probability neural network (PNN). 344 FT-IR spectra were collected from 172 pairs of fresh normal and abnormal stomach tissue's samples. After preprocessing, 5 features were extracted with DWT analysis. Based on the PNN classification, all FT-IR spectra were classified into three categories. The accuracy of identifying normal gastric tissue, early gastric cancer tissue and gastric cancer tissue samples were 100.00, 97.56 and 100.00%, respectively. This result indicated that FT-IR with DWT and PNN could effectively and easily diagnose gastric cancer in its early stages. [ABSTRACT FROM AUTHOR]

An acoustic asymmetric transmission device exhibiting unidirectional transmission property for acoustic waves is extremely desirable in many practical scenarios. Such a unique property may be realized in various configurations utilizing acoustic Zeeman effects in moving media as well as frequency-conversion in passive nonlinear acoustic systems and in active acoustic systems. Here we demonstrate a new acoustic frequency conversion process in a time-varying system, consisting of a rotating blade and the surrounding air. The scattered acoustic waves from this time-varying system experience frequency shifts, which are linearly dependent on the blade's rotating frequency. Such scattering mechanism can be well described theoretically by an acoustic linear time-varying perturbation theory. Combining such time-varying scattering effects with highly efficient acoustic filtering, we successfully develop a tunable acoustic unidirectional device with 20 dB power transmission contrast ratio between two counter propagation directions at audible frequencies. [ABSTRACT FROM AUTHOR]