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In recent years, neural networks based on attention mechanisms have seen increasingly use in speech recognition, separation, and enhancement, as well as other fields. In particular, the convolution-augmented transformer has performed well, as it can combine the advantages of convolution and self-attention. Recently, the gated attention unit (GAU) was proposed. Compared with traditional multi-head self-attention, approaches with GAU are effective and computationally efficient. In this CGA-MGAN: MetricGAN based on Convolution-augmented Gated Attention for Speech Enhancement, we propose a network for speech enhancement called CGA-MGAN, a kind of MetricGAN based on convolution-augmented gated attention. CGA-MGAN captures local and global correlations in speech signals at the same time by fusing convolution and gated attention units. Experiments on Voice Bank + DEMAND show that our proposed CGA-MGAN model achieves excellent performance (3.47 PESQ, 0.96 STOI, and 11.09 dB SSNR) with a relatively small model size (1.14 M). [ABSTRACT FROM AUTHOR]

• The influence of EYDF on the statistical properties of RFLs was studied for the first time through experiments. • The addition of EYDF affects the PDFs of temporal characteristics. • At high pump power, the radiation of both lasers is fully uncorrelated. In this paper the influence of un-pumped Erbium-Ytterbium doped fibers (EYDF) on the statistical properties of random fiber lasers (RFLs) with linear cavity based on Rayleigh scattering is investigated. The experimental results show that the probability density function (PDF) of temporal characteristics of both lasers with and without un-pumped EYDF are asymmetrically distributed near threshold and Gaussian distributed far away over threshold. The width of the PDFs first increases and then decreases with pump power when the un-pumped EYDF is not inserted, while the width of the PDFs continuously increases with pump power when the un-pumped EYDF is inserted, which indicates that EYDF insertion makes the laser more stable at lower pump power and more unstable at higher pump power. The radiation with un-pumped EYDF is fully uncorrelated at high pump power. And the radiation without un-pumped EYDF is also fully uncorrelated at high pump power. [ABSTRACT FROM AUTHOR]

In this research, the combination of theoretical approach and numerical simulation was employed to comprehensively understand the initiation mechanism of time-delayed rockburst and analyze the time-delayed failure laws for surrounding rock after excavation unloading without prompt support. The investigations are principally at the angle of time and space, which refers to the creep property and damaged scope for surrounding rock. For the theoretical method, the analytical elastic and elastoplastic models for deep tunnel cross section and the creep model for brittle rock material from a microscopic view were combined. It was found that the time-delayed failure for surrounding rock resulted from the damage accumulation with crack development during the creep process. The surrounding rock with the elastic state was more stable than that in the plastic zone and the creep duration increased with growing distance from the center of tunnel section. Based on the theoretical creep model, the numerical simulation ulteriorly analyzed the brittle creep duration on the key positions. The surrounding rock tended to fail more in the strong excavation damage zone (SEDZ) than that in the weakly damaged zone (WEDZ), and brittle creep failure mainly occurred on the excavation border (EB) in a short space of time. In addition, the increase in the radius for tunnel cross section and the higher in situ stress distribution around the opening led to the acceleration of the creep process for surrounding rock, and the irregular cross-section shape of the tunnel caused the local damaged range extension and decreased the duration for time-delayed failure. [ABSTRACT FROM AUTHOR]

• The study provided an advanced finite element analysis with a comprehensive comparison and visualization of mechanical stresses, strains, and displacements, enhancing pre-surgical planning and prediction of post-operative outcomes. • Both the commercial and 3D-printed Ti6Al4V titanium plates showed close stress, strain, and displacement values under varying occlusal forces, indicating a marginal difference in biomechanical behaviors. • The 3D-printed Ti6Al4V plates demonstrated slightly lower displacement and strain under equivalent forces, suggesting a potential advantage in maintaining structural integrity post-operation. • Maximum stress concentrations were observed at the vertical change in the left posterior area between maxillary segments, with the 3D-printed model exhibiting higher stress values, potentially impacting long-term stability. • Our study supports the use of 3D-printed personalized fixation plates for their proven postoperative accuracy and excellent anatomical fit. However, in terms of mechanical stability, there is no significant difference under the 125, 250, 500 N/mm2 occlusal forces. To evaluate and compare the biomechanical behavior of three-dimensionally (3D) printed patient-specific Ti6Al4V with commercially made titanium mini plates following Lefort-I osteotomy using finite element analysis. Le Fort I osteotomy was virtually simulated with a 5 mm maxillary advancement and mediolateral rotation in the coronal plane, resulting in a 3 mm gap on the left side's posterior. Two fixation methods were modeled using software to compare 3D-printed Ti6Al4V and commercial titanium mini plates, both featuring a 4-hole l -shape with thicknesses of 0.5 mm and 0.7 mm at the strategic piriform rim and zygomaticomaxillary buttress locations. Using ANSYS R19.2, finite element models were developed to assess the fixation plates and maxilla's stress, strain, and displacement responses under occlusal forces of 125, 250, and 500 N/mm². This comparative analysis revealed slight variation in stress, strain, and displacement between the two models under varying loading conditions. Stress analysis indicated maximum stress concentrations at the vertical change in the left posterior area between maxillary segments, with the Ti6Al4V model exhibiting slightly higher stress values (187 MPa, 375 MPa, and 750 MPa) compared to the commercial titanium model (175 MPa, 351 MPa, and 702 MPa). Strain analysis showed that the commercial titanium model recorded higher strain values at the bending area of the l -shaped miniplate. Moreover, displacement analysis revealed a maximum of 3 mm in the left posterior maxilla, with the Ti6Al4V model demonstrating slightly lower displacement values under equivalent forces. The maximum stress, strain, and segment displacement of both fixation models were predominantly concentrated in the area of the gap between the maxillary segments. Notably, both fixation models exhibited remarkably close values, which can be attributed to the similar design of the fixation plates. [ABSTRACT FROM AUTHOR]

Based on governance value analysis, social network theory, and resource dependence theory, this study proposed and tested a conceptual model exploring relationship flexibility in the third-party logistics (3PL) context. It contributes to knowledge of the relationship management and value creation dynamics with 3PL providers, important members of today's marketing channels. Specifically, network embeddedness and explicit contract are found to be positively related to 3PL customer firms' relationship flexibility that further has a positive significant impact on logistics performance. Theoretical contributions and managerial implications are discussed. [ABSTRACT FROM AUTHOR]

The stability of deep rock engineering, especially during the excavation, is inextricably linked to the time-dependent mechanical properties of brittle rock. Therefore, the uniaxial creep test in a multilevel loading path is carried out, accompanying the real-time DIC (digital image correlation) and AE (acoustic emission) technologies. For the quartz sandstone, the lateral strain is more sensitive to increasing stress levels, and the lateral ductility is more significant during the creep process. The saturated quartz sandstone shows a certain bearing capacity before the volumetric dilation predominance. The softening effect of moisture causes a nearly invariable Poisson's ratio during the middle stress stages, as well as the more notable increasing trend of a steady creep rate with an increasing stress level, reflected by the larger slope and the intercept in the fitting relations. The main shear pattern and the combination of the shear and splitting failures are separately shown by the dry and saturated quartz sandstone. For the granite, both compression and extension exist in the creep deformation, and the failure may first occur in the prominent deformation area with a cracking noise. The AE hits present a similar time-dependent behavior to the strain of rock, and the attenuation trend happens in both the AE amplitude and energy before the rock enters the unsteady phase. The incomplete specimen of granite exhibits a lower strength and a larger deformation, owing to the more remarkable damage accumulation reflected by the spatial distribution of the AE event points. [ABSTRACT FROM AUTHOR]

While reverse logistics has gained significant interest in recent years, the research on its antecedents is still far from comprehensive. The current study utilizes data collected from China to empirically test a conceptual model that is developed based on the resource based view of the firm. It is proposed that returns management orientation, internal collaboration, and information support are important predictors of reverse logistics performance. The structural equation modeling analysis supports these proposed relationships. Furthermore, the current study also confirms the positive relationship between a firm's reverse logistics performance and market performance. [ABSTRACT FROM AUTHOR]

The present study utilizes starch as the primary raw material for preparing a water‐resistant biomass adhesive to replace formaldehyde‐based resin adhesive, which is subsequently used in plywood production. The preparation process of starch‐based adhesive (SBA) was optimized using response surface methodology (RSM), and the effects of the mass ratio of starch to tannic acid, the dosages of phragmites fiber and boric acid on wet‐bond strength were studied. The quadratic regression model of SBA showed significant results (p < 0.0001). The optimal preparation condition was that the mass ratio between starch and tannic acid was 5:2, in the dosages of 2.9% for phragmites fibers and 3.2% for boric acid. The wet‐bond strength of the plywood prepared with this adhesive was 1.73 MPa. Characterization analysis showed that the hydroxyl group on the surface of starch and tannic acid had complexation with boric acid, which improved the wet‐bond strength, water resistance, and, thermal stability of the adhesive. The alkali‐treated phragmites fibers had better compatibility with the starch matrix than the original fiber, which improved the cohesion of the SBA and increased the wet‐bond strength by 26%. Highlights: The phragmites fibers have been used to reinforce starch‐based adhesives.Boric acid facilitates the formation of crosslinked structures.The phenolic hydroxyl group in tannins provides excellent water resistance.Phragmites fiber exhibits good compatibility with the adhesive matrix.The cured starch‐based adhesive has excellent wet‐bond strength. [ABSTRACT FROM AUTHOR]

Summary: Two‐component systems (TCSs) are predominant means by which bacteria sense and respond to environment signals. Genome of Pseudomonas putida contains dozens of putative TCS‐encoding genes, but phenotypical–genotypical correlation and transcriptional regulation of these genes are largely unknown. Herein, we characterized function and transcriptional regulation of a conserved P. putida TCS, named TarR–TarS. TarS (PP_0769) encodes a potential histidine kinase, and tarR (PP_0768) encodes a potential response regulator. Protein–protein interaction assay and phosphorylation assay confirmed that TarR–TarS was a functional TCS. Growth assay under antibiotics revealed that TarR–TarS positively regulated bacterial resistance to multiple antibiotics. Pull‐down assay revealed that TarR directly interacted with PP_0800 (a hypothetical protein) and GroEL (the chaperonin). GroEL played a positive role in antibiotic resistance, while PP_0800 seemed to have no effect on antibiotic resistance. The regulator FleQ indirectly activated tarR–tarS transcription. However, the second messenger c‐di‐GMP antagonized FleQ activation to inhibit tarR–tarS transcription. The sigma factor FliA directly activated tarR–tarS transcription via a consensus motif. These findings reveal function and transcriptional regulation of TarR–TarS, and enrich knowledge regarding the relationship between c‐di‐GMP and antibiotic susceptibility in P. putida. [ABSTRACT FROM AUTHOR]

Frigocyclinone is a novel antibiotic with antibacterial and anticancer activities. It is produced by both Antarctica-derived Streptomyces griseus NTK 97 and marine sponge-associated Streptomyces sp. M7_15. Here, we first report the biosynthetic gene cluster of frigocyclinone in the S. griseus NTK 97. The frigocyclinone gene cluster spans a DNA region of 33-kb which consists of 30 open reading frames (ORFs), encoding minimal type II polyketide synthase, aromatase and cyclase, redox tailoring enzymes, sugar biosynthesis-related enzymes, C-glycosyltransferase, a resistance protein, and three regulatory proteins. Based on the bioinformatic analysis, a biosynthetic pathway for frigocyclinone was proposed. Second, to verify the cloned gene cluster, CRISPR-Cpf1 mediated gene disruption was conducted. Mutant with the disruption of beta-ketoacyl synthase encoding gene frig20 fully loses the ability of producing frigocyclinone, while inactivating the glycosyltransferase gene frig1 leads to the production of key intermediate of anti-MRSA anthraquinone tetrangomycin. Cloning and identification of the frigocylinone biosynthetic gene cluster provide a deep insight into the biosynthetic pathway and will contribute to development of novel antibiotics via genetic engineering. [ABSTRACT FROM AUTHOR]

In this study, glycol diglycidyl ether was used as a crosslinker to facilitate the formation of a cross-linked network structure between starch and gelatin, and the incorporation of self-assembled modified reed fibers resulted in the synthesis of an environmentally friendly starch-based adhesive. The results of Fourier transform infrared spectroscopy, scanning electron microscope, X-ray diffractometer, rheological properties and thermogravimetric analysis showed that starch and gelatin formed a dense macromolecular network structure under the action of crosslinker. The shear strength, water resistance, rheology and thermal stability of the starch-based adhesive were improved, with dry and wet strengths of 6.46 MPa and 1.32 MPa, respectively. The computer simulation analysis showed that starch and gelatin had better compatibility. Compared with unmodified starch, the crosslinked adhesive had less hydrogen bond, lower water absorption and more dense network structure, which provided a reference for the future study of the modification of starch-based adhesive and the mechanism of molecular interaction. [Display omitted] • There is a strong adhesion between the modified fiber and the adhesive matrix. • The simulation analysis showed that starch and gelatin had good compatibility. • Reed fiber enhances the shear strength of starch-based adhesive. • Cross-linked modified starch-based adhesive has excellent water resistance. [ABSTRACT FROM AUTHOR]

Abstract: This study contributes to the online auction literature by empirically examining the differences across three groups (current users, past users, and nonusers) in terms of their emphasis on supplier collaboration, cost management, and sales revenue and profit enhancement. The paper further compares the online auction usages for maintenance/repair/operations and shipping and transportation services across high and low groups in supplier collaboration and cost management. A survey of supply chain professionals coupled with appropriate statistical analysis was employed to investigate adoption and utilization of online auctions. Study findings indicate significant differences between users and nonusers. Study findings specifically indicate that current online auction users have a greater belief in the auctions as a cost containment tool than past or nonusers. It was also found that nonusers place a greater level of importance on supplier collaboration and sales revenue and profit enhancement than either current or past users. [Copyright &y& Elsevier]

Starch is a biomass polymer material with a high yield and comprehensive source. It is used as a raw material for preparing adhesives because of its highly active hydroxyl group. However, poor adhesion and water resistance hinder the application of starch-based adhesives (SBAs). Based on this, the starch was modified through graft copolymerization with itaconic acid as a cross-linking agent, methyl methacrylate and methyl acrylate as copolymers. Additionally, reed fibers were synergistically modified with polydopamine deposition to prepare an environmentally friendly SBA used in plywood production. Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (1H NMR), X-ray diffraction (XRD), and thermogravimetric analysis (TG) demonstrate that copolymerization of methyl methacrylate and methyl acrylate with starch improves the shear strength, water resistance, and thermal stability of the SBA. Compared to unmodified starch, the modified SBA exhibits a 129 % increase in dry strength and achieves a wet strength of 1.36 MPa. Fukui function, Frontier orbit theory, and molecular dynamics simulation have shown that itaconic acid promotes the copolymerization of starch and acrylate monomers. The modified starch has fewer hydrogen bonds, less order, and a denser macromolecular network structure, which provides a reference for studying the molecular interaction mechanisms of SBAs. [Display omitted] • The modified reed fiber exhibits good compatibility with the starch matrix. • The graft copolymerized starch-based adhesive has excellent shear strength. • The local reactivity of reactants has been analyzed using Fukui function. [ABSTRACT FROM AUTHOR]

Microsupercapacitors (µSCs) are attractive electrochemical energy storage devices serving as alternatives to batteries in miniaturized portable electronics owing to high‐power density and extended cycling stability. Current state‐of‐the‐art microfabrication strategies are limited by costly steps producing materials with structural defects that lead to low energy density. This paper introduces an electrode engineering platform that combines conventional microfabrication and polymerization from the vapor phase producing 3D µSCs of the conducting polymer poly(3,4‐ethylenedioxythiophene) (PEDOT). A sputtered Fe2O3 precursor layer enables deposition of a 250 nm thick polymer coating comprised of a high packing density of vertically aligned PEDOT nanofibers possessing exceptional electrical conductivity (3580 S cm−1). The 3D µSCs exhibit state‐of‐the‐art volumetric energy density (16.1 mWh cm−3) as well as areal (21.3 mF cm−2) and volumetric (400 F cm−3) capacitances in 1 m H2SO4 aqueous electrolyte. These figures of merit represent the highest values among conducting polymer‐based µSCs. Electrochemical performance is controlled by investigating coating thickness, gap distance, fractal geometry, and gel electrolyte (1 m H2SO4/polyvinyl alcohol). The quasisolid‐state µSCs exhibit extended rate capability (50 V s−1), retain 94% of original capacitance after 10 000 cycles and remain thermally stable up to 60 °C. [ABSTRACT FROM AUTHOR]

Tsunami disasters have frequently occurred in recent years. More and more researchers are focusing on this topic. To investi-gate the tsunami bore impact mechanism on a container model, a multi-functional slope-changing tsunami flume is built in this study. To simulate a tsunami bore, a dam-break wave was generated by a free-falling gate in a reservoir. A needle water level gauge and a high-speed camera were used to measure the tsunami wave heights and velocities for different storage water levels in the test flume, and the corresponding Froude numbers of tsunami waves were also calculated. The factors af-fecting the movement distance of the tsunami wave impacting the container model are explored in this experiment, and the results show that the movement distance is positively correlated with the storage water level, and negatively correlated with the container density and the coast slope. [ABSTRACT FROM AUTHOR]

• Stable pulse generated from an all-optical passively Q-switched random fiber laser with cascaded doped fiber is demonstrated for the first time. • The cascaded EDF and EYDF work as saturable absorber and the RPS-FBG is used to provide random feedback. • The cascaded doped fiber shows different nonlinear characteristics under different pump powers, which results in pulse with different properties. • The random fiber laser not only has low-threshold but also exhibits stable pulse controlled by two pump lasers. In this paper, stable pulse train generated from an all-optical passively Q-switched random fiber laser (RFL) with cascaded doped fiber segments and random phase-shift Bragg grating is demonstrated for the first time. A 25 mm random phase-shifted fiber Bragg grating (RPS-FBG) is used to provide random feedback. Two cascaded doped fiber segments, Erbium-doped fiber (EDF) and Erbium-Ytterbium co-doped fiber (EYDF), are used as saturable absorber when the fibers are incompletely pumped. The characteristics of the RFL under different power of two pump lasers are investigated. The doped fiber has different nonlinearities under different pump power combinations, which results in passively Q-switched pulse with repetition rate from 5.1 kHz to 29.3 kHz. The RFL not only has low-threshold but also exhibits stable random pulse with repetition rate and pulse width controlled by the combination of two pump powers. [ABSTRACT FROM AUTHOR]

• Dynamic and bifurcation characteristics of actively Q-switched Erbium-doped fiber ring laser with large modulation index are investigated theoretically and experimentally. • Considering pump power and modulation index as control parameters, the laser occurs multiple pulse splitting states, while chaotic outputs are present during the pulse splitting evolution. • Considering modulation frequency and modulation index as control parameters, the laser occurs multiple periodic states and chaos response. • At large modulation index, the formed multiple periodic route exhibits a reverse multiple periodic bifurcation after the maximum multiple period. Dynamic and bifurcation characteristics of actively Q-switched Erbium-doped fiber ring laser (EDFRL) with large modulation index are investigated theoretically and experimentally. Using pump power and modulation index as control parameters, the laser exhibits a pulse splitting dynamic response process. More pulse splitting states such as double pulse, triple pulse, and quadruple pulse can be achieved in the process of increasing pump power and modulation index, while chaotic outputs are present during the pulse splitting evolution. The dynamic response of the output due to modulation index and modulation frequency change is also discussed. At large modulation index, the formed multiple periodic route exhibits a reverse multiple periodic bifurcation after the maximum multiple period. The dynamic response of Q-switched EDFRL with large modulation index contributes to a more comprehensive understanding of the dynamic characteristics of EDFRL and its applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A biomimetic wellbore stabilizer TA-PVA was developed in WBDFs for NGH reservoir. • The strong adsorption mechanism of TA-PVA is based on hydrogen bond. • TA-PVA can bond clay mineral particles and hydrate particles simultaneously. • TA-PVA has no endothermic and exotherm phenomenon at 0–60 ℃. Natural gas hydrate (NGH) in marine is usually reserved in the pores or cracks of weakly cemented argillaceous siltstones. Moreover, the hydrates are susceptible to variations in temperature and pressure conditions when water-based drilling fluids (WBDFs) are drilled into hydrate reservoirs, leading to the hydrate in-situ decomposition and severe sand production. In this work, an inexpensive and facilely prepared biomimetic wellbore stabilizer with strong adsorption of multiple hydrogen bonds was prepared by fusing catechol-rich tannic acid (TA) and polyvinyl alcohol (PVA) with polyol hydroxyl adsorption function, referred to as TA-PVA complex (TA-PVA). TA-PVA was added to WBDFs to strengthen the NGH reservoir wellbore for ensuring the safety of drilling process in a wide temperature range (2-60℃). The microscopic characterization of TA-PVA and its cohesion mechanism with argillaceous siltstone was investigated by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The mechanical properties of skeleton of the artificial hydrate cores were evaluated by compressive strength test, with maximum compressive strength reaching 0.45 MPa. And the adhesion force of TA-PVA to the probe modified by silica microsphere (PSM) was further studied by AFM. Meanwhile, the adhesion forces between TA-PVA and cyclopentane hydrate particles were measured at 1.5℃. Adhesion test results demonstrate that TA-PVA can bond clay particles, quartz sand and hydrate particles together. In detail, the adhesion force between TA-PVA and PSM reaches more than 164.46 mN/m, the adhesion force between TA-PVA droplet and cyclopentane hydrate particle reaches 43.19 mN/m. The differential scanning calorimetry (DSC)curves demonstrate that TA-PVA releases no heat between 0 and 60 °C, indicating that TA-PVA has no impact on the decomposition of NGH, showing the potential to maintain the integrity of NGH reservoir. [ABSTRACT FROM AUTHOR]

Many original equipment manufacturers (OEMs) allow third-party remanufacturers (3PRs) to perform remanufacturing operations of branded or patented products – through either outsourcing or authorization. This study compares these two modes by modeling the game between the OEM and the 3PR on equilibrium quantities, prices, and profits. The results suggest that when consumers perceive the remanufactured products with a low value, the 3PR prefers the authorization approach; otherwise the 3PR prefers the outsourcing approach. However, in both scenarios, the OEM obtains higher profit through outsourcing than through authorization. Our further analysis compares two modes’ impacts on consumer surplus, social welfare, and environment. [ABSTRACT FROM AUTHOR]

A survey of businesses in the automobile aftermarket industry provided insights into how reverse logistics performance can be influenced by a few key strategic decisions. Resource commitment is critical to program performance. However, it is important that the resources be focused on developing information technology capabilities. This, no doubt, is reflective of the nature of reverse logistics. Information support––for authorizing, tracking, and handling returns––can positively impact both economic and service quality-related performance. [Copyright &y& Elsevier]