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An interfacial C-S bond bridged ZnS/C 3 N 5 S-scheme heterojunction was constructed for photocatalytic H 2 evolution. Benefiting from the interfacial covalent bond, enhanced internal-electric-field strength, and accelerated surface photocatalytic reaction, the photocatalytic H 2 production of ZnS/C 3 N 5 was 3.2 and 2.5 times higher than those of ZnS/C 3 N 4 and ZnS/C 3 N 5 -300 without C-S bond. [Display omitted] • C-S bond is susceptive to preparation temperatures, and it is broken above 300 °C. • C-S bond promotes e − separation and improves H 2 O adsorption and activation behaviors. • IEF strength of ZnS/C 3 N 5 with opposite direction is 2.6 times than that of ZnS/C 3 N 4. • e − transfer respectively follow S-scheme and type-II pathway in ZnS/C 3 N 5 and ZnS/C 3 N 4. • H 2 yield of ZnS/C 3 N 5 is 3.2 and 2.5 times than ZnS/C 3 N 4 and ZnS/C 3 N 5 -300 without C-S. An interfacial C-S bond bridged ZnS/C 3 N 5 heterojunction was constructed for photocatalytic H 2 evolution. Different from traditional type-II ZnS/C 3 N 4 heterojunction, the electron transfer followed S-scheme pathway, due to opposite internal-electric-field (IEF) directions in these two heterojunctions. The C-S bond formation was carefully investigated, and they were susceptive to the preparation temperatures. In photocatalytic reaction, C-S bond was functioned as the "high-speed channel" for electron separation and transfer, and the IEF strength in ZnS/C 3 N 5 was 1.86 × 108 V/m, 2.6 times higher than that in ZnS/C 3 N 4. Moreover, the C-S bond also altered the surface molecular structure of ZnS/C 3 N 5 , and hence the surface reaction was accelerated via improving H 2 O adsorption and activation behaviors. Benefiting from the S-scheme pathway, enhanced IEF strength, and accelerated surface reaction, the photocatalytic H 2 production over ZnS/C 3 N 5 reached up to 20.18 mmol/g/h, 3.2 and 2.5 times higher than those of ZnS/C 3 N 4 and ZnS/C 3 N 5 -300 without C-S bond. [ABSTRACT FROM AUTHOR]

[Display omitted] • NH 4 BS can dissolve in basic electrolyte without cosolvent. • NH 4 BS can alleviate the passivation of electrode surfaces by dissolving Li 2. • NH 4 BS can increase the dissociation degree of long-chain polysulfides.NH4BS can increase the dissociation degree of long-chain polysulfides. Based on the dissolution and conversion mechanism of lithium-sulfur (Li-S) batteries, insulating solid short-chain polysulfides (Li 2 S 2 /Li 2 S) will continuously passivate and corrode the active interface of cathode and anode, which seriously affects its performance. Herein, ammonium benzenesulfonate (NH 4 BS) is proposed as a soluble ammonium salt to dissolve Li 2 S in the ether electrolyte, according to the inductive effect of NH 4 + cation and O atom on Li-S bond. This is beneficial to alleviate the interface problem of electrodes and irreversible loss of active materials. Noticeably, soluble Li 2 S regulates its deposition behavior from 2D to 3D, which is conducive to the more effective use of conductive surface. Moreover, the addition of NH 4 BS can increase the dissociation degree of long-chain polysulfides, so that the diffusion rate and reaction kinetics of active substances are improved. Profiting from these functions, the Li-S cells with NH 4 BS act out excellent cyclic stability in the long cycle of 0.5 C and 2 C. Under the extreme conditions of high sulfur loading and low electrolyte-sulfur ratio, the cells with NH 4 BS can cycle stably for 196 cycles, which significantly prolongs the battery life. The proposal of NH 4 BS broadens a new idea to solve the interface problem of Li-S cells and stimulate the research enthusiasm of developing soluble ammonium salt. [ABSTRACT FROM AUTHOR]

Aboveground biomass (AGB) in grasslands directly reflects the net primary productivity, making it a sensitive indicator of grassland resource quality and ecological degradation. Accurately estimating AGB over large regions to reveal long-term AGB evolution trends remains a formidable challenge. In this study, we divided Inner Mongolia Autonomous Region (IMAR) grasslands into three study regions based on their spatial distribution of grassland types. We combined remote sensing data with ground-based sample data collected over the past 19 years from 6114 field plots using the Google Earth Engine platform. We constructed random forest (RF) and traditional regression AGB inversion models for each region and selected the best-performing model through accuracy assessment to estimate IMAR grassland AGB for the period 2000–2022. We also examined the trends in AGB changes and identified the driving forces affecting IMAR grasslands through the application of Theil-Sen estimation, Mann-Kendall trend analysis, and the Geodetector model. The main findings are as follows: (1) Compared with the univariate parametric traditional regression model, the AGB monitoring accuracy of the multivariate non-parametric RF model in the three study regions increased by 5.94%, 5.08% and 19.14%, respectively. (2) The average AGB per unit area of IMAR grasslands from 2000 to 2022 was 731.41 kg/hm2, with alpine meadow having the highest average AGB (1271.70 kg/hm2) and temperate grassland desertification having the lowest (469.06 kg/hm2). IMAR grasslands exhibited an overall increasing trend in AGB over the past 23 years (6.01 kg/hm2•yr), with the increasing trend covering 83.52% of the grassland area and the decreasing trend covering 16.48%. (3) Spatially, IMAR grassland AGB showed a gradual decline from northeast to southwest and exhibited an increasing trend with increasing longitude (45.423 kg/hm2 per degree) and latitude (71.9 kg/hm2 per degree). (4) Meteorological factors were the most significant factors affecting IMAR grassland AGB, with precipitation (five-year average q value of 0.61) being the most prominent. In the western part of IMAR, where precipitation is consistently limited throughout the year, the primary drivers of influence were human activities, with particular emphasis on the number of livestock (with a five-year average q value of 0.44). It is evident that reducing human activity disturbance and pressure in fragile grassland areas or implementing near-natural restoration measures will be beneficial for the sustainable development of grassland ecosystems. The results of this research hold substantial reference importance for the protection and restoration of grasslands, the supervision and administration of grassland resources, as well as the development of policies related to grassland management. [Display omitted] • The aboveground biomass (AGB) of grasslands in IMAR increased over the past 23 years. • IMAR grassland AGB shows an upward trend with increasing longitude and latitude. • Precipitation is the main factor affecting grassland AGB in IMAR. • Human activities have a greater impact on the grassland AGB in western IMAR. [ABSTRACT FROM AUTHOR]

Under stressful conditions, bacteria can enter viable but non-culturable (VBNC) state to survive. VBNC cells lost ability to grow on routine culture medium but are still alive and may revive in suitable conditions. The revived cells can consume nutrients or produce toxins, leading to food spoilage or human illness, posing great risk to food safety and public health. Previously, we have reported that high pressure carbon dioxide (HPCD), an environment-friendly sterilization technology, can induce VBNC formation. However, the underlying mechanism is unclear. By performing a comprehensive transcriptomic analysis, we revealed that HPCD initiated high expression of asr , encoding an acid shock protein, could promote VBNC formation of E. coli O157:H7. Quantitative reverse transcription PCR analysis suggested that high expression of asr (i) inhibited acid resistance (AR) systems, resulting in endogenous proton accumulation; (ii) inhibited hchA expression, a protein stabilizing factor. The two effects resulted in endogenous protein aggregation, which was highly correlated to VBNC formation. Accordingly, HPCD-stressed cells exhibited decreased efficiency of electron transfer chain and ATP production, which was also contributory to cytoplasmic protein aggregation. Taken together, HPCD-initiated high expression of Asr coupled with decreased ATP production led to protein aggregation, finally promoted the cells to enter VBNC state. • Molecular responses of E. coli O157:H7 to HPCD were investigated to explore crucial factors regulating VBNC formation. • Acid shock protein Asr was found to be involved in regulating HPCD induced VBNC formation. • Asr inhibited AR systems / protein stabilizer HchA to facilitate endogenous protein aggregation to promote VBNC formation. [ABSTRACT FROM AUTHOR]

In this work, we investigate both numerically and theoretically the sound generated by entropy waves passing through sudden area expansions. This is a canonical configuration representing internal flows with flow separation and stagnation pressure losses. The numerical approach is based on a triple decomposition of the flow variables into a steady mean, a small-amplitude coherent part, and a stochastic turbulent part. The coherent part contains acoustic, vortical, and entropy waves. The mean flow is obtained as the solution of the Reynolds-Averaged Navier–Stokes (RANS) equations. The equations governing the coherent perturbations are linearised and solved in the frequency domain. To account for the effect of turbulence on the coherent perturbations, a frozen eddy viscosity model is employed. When entropy fluctuations pass through the area expansion, the generated entropy noise behaves as a low-pass filter. The numerical predictions of the noise at low frequencies are compared to the predictions of compact, quasi-one-dimensional, and isentropic theory and large discrepancies are observed. An alternative model for the generated entropy noise tailored for area expansions is then proposed. Such model is based on the conservation of mass, momentum, and energy written in integral form. The model assumes zero frequency and the one-dimensionality of the flow variables far upstream and downstream of the expansion. The predictions of this model agree well with the numerical simulations across a range of finite subsonic Mach numbers including low, intermediate, and high Mach numbers. The contributions of this work are both numerical and theoretical. Numerically, a triple decomposition adapted to high-Mach-number, compressible flows is introduced for the first time in the context of acoustic simulations. From a theoretical point of view, the quasi-steady model proposed here correctly captures the low-frequency entropy noise generated at sudden area expansions, including at high subsonic Mach numbers. • Isentropic, quasi-1D theory overpredicts the entropy noise at sudden area expansions • We propose a numerical approach based on a triple decomposition for compressible flows. • We propose an alternative compact analytical model tailored to area expansions. [ABSTRACT FROM AUTHOR]

Multistimuli responsive materials based on the viologen coordination polymers have attracted much interest in the past few years due to the increasing demand for smart materials. In this paper, based on a viologen ligand 1-(3-carboxybenzyl)- 4,4′-bipyridinium chloride (Hcbbpy) and zinc(II) ion, a new crystalline complex, namely, {[Zn(cbbpy)Cl 2 ]·H 2 O} n (1) has been designed and synthesized. In complex 1 , every cbbpy ligand as a bridge links two Zn2+ ions via carboxylate O atom and pyridine N atom to extend to a 1D zigzag chain. The 1D chains are extended to 3D supramolecular structure through π···π stacking and hydrogen bonding. More importantly, 1 exhibits fast photochromic behaviors in response to UV and X-ray due to the formation of viologen radicals. Complex 1 also shows photo-modulated luminescence property in the solid state. In addition, complex 1 can be deposited on filter paper and displays the potential application as inkless print material. [Display omitted] • A new viologen complex was successfully synthesized and characterized. • Complex 1 shows fast response to UV light and X-ray irradiation. • Complex 1 can be deposited on filter paper and displays as inkless print material. [ABSTRACT FROM AUTHOR]

Traditional bridge health monitoring is both expensive and time-consuming because of the need for installing a large quantity of sensors on the bridge. The indirect monitoring method as a feasible alternative has become popular over the last decade, as useful information can be gathered from moving vehicles installed with sensors by considering vehicle-bridge interaction. This paper describes an indirect time-varying modal parameter identification method for bridges under a moving test vehicle. A novel reference-driven S-transform is proposed for the parametric modal identification of time-varying structural systems with non-stationary characteristics based on a multisensory arrangement, comprising a fixed reference sensor installed on the bridge and another movable sensor installed on a moving test vehicle. By the phase-preservation property of S-transform and the multisensory time-frequency analysis, the proposed iterative reference-driven S-transform can be used to extract the time-varying modal parameters of the vehicle-bridge system when the vehicle moves on the bridge. Based on the coherence between measurements from the sensors mounted on the bridge and vehicle, one can track the time-varying characteristics by combining the spatial and time-frequency information obtained by the multisensory array. The efficiency of the proposed reference-driven S-transform method is validated by numerical simulations and laboratory experiments using a simply supported beam with a moving vehicle. The effects of the vehicle property, driving speed, road roughness and measurement noise are discussed. The numerical and experimental results have demonstrated that the proposed method is useful for time-varying parameter extraction with a multisensory system. This will be useful to structural condition monitoring of bridges. [ABSTRACT FROM AUTHOR]

Our previous that HMMR upregulation independently predicts poor survival in patients with papillary muscle-invasive bladder cancer (MIBC). In this study, we explored its downstream regulations and the potential transcriptional factors activating its expression. MIBC derived T24 cells, and non-MIBC (NMIBC) derived RT4 cells were used for in vitro and in vivo studies. HMMR expression enhanced cell proliferation, the expression of mesenchymal markers, and cell invasion. It induced the nuclear entry of β-catenin, increased its active form in the nuclear part, and elevated the relative TOP/FOP activity. The promoter region of HMMR has a canonical FKH motif. FOXM1 bound to this site and activated HMMR transcription. HMMR knockdown significantly weakened FOXM1 overexpression induced bladder cancer growth, invasion, partial epithelial-to-mesenchymal transition (pEMT), as well as the activation of the Wnt/β-catenin signaling pathway. In conclusion, the findings in this study expanded our understanding of the mechanisms underlying HMMR dysregulation and the functional role of the FOXM1-HMMR axis in bladder cancer. [ABSTRACT FROM AUTHOR]

• An S-transform-based time-varying characteristic analysis method is proposed to extract the frequency fluctuations. • The approximation description between structural instantaneous frequency and S-transform is deducted. • A novel Gaussian window function is proposed for S-transform to improve the time-frequency resolution. • The laboratory vehicle-bridge dynamic interaction experiment is conducted for verification. • Parametric study involving road surface roughness are discussed in the numerical simulation. The health monitoring of bridge under moving vehicles demands a high-efficient time-varying characteristic analysis method to extract the frequency fluctuations caused by vehicle-bridge dynamic interaction effect. Characteristics identification of structures becomes a challenging task especially when time-varying vibration modes are involved. For this purpose, an instantaneous frequency identification technique based on modified S-transform reassignment is presented in this paper. Firstly, the general approximation between structural instantaneous frequency and S-transform is deduced. The Gaussian window is employed in S-transform and a novel first-order frequency function with two parameters is added into the Gaussian window function to improve the time–frequency resolution. The added function makes the Gaussian window scalable-sliding and the optimal values of the parameters are selected based on time–frequency concentration criterion. Considering the Rényi entropy as the measurement of criterion, the information performance extracted from S-transform spectrogram is evaluated. Then the time–frequency reassignment technique is applied to improve the readability of S-transform spectrogram to assure the accuracy of the extracted instantaneous characteristics, which enhances the time–frequency concentration efficiently. The proposed method is verified by numerical simulation, the results obtained by the spectrograms derived from short-time Fourier transform, wavelet transform, modified S-transform and reassigned modified S-transform are compared. Afterwards, the time-varying frequency components related to the vehicle-bridge interaction are extracted from the response signal. Numerical simulations involving different parameter analysis and laboratory experiments are conducted to validate the flexibility of the technique in vehicle-bridge system. The effect of vehicle weight, speed and road surface roughness on the identified results are discussed. Both numerical and experimental results have demonstrated that a higher time–frequency concentration in the spectrogram can be observed of the proposed modified S-transform reassignment method than other time–frequency methods, and subsequently a higher accuracy of instantaneous frequency identification is achieved which provides a good tool for time-varying characteristic analysis in bridge health monitoring. [ABSTRACT FROM AUTHOR]

The acoustic characteristics of bluff-body burners play a critical role in the combustion stability for combustors using this type of burners. The acoustic modelling of an axisymmetric bluff-body burner entails properly capturing the sound-vortex interaction for the flow through the annular aperture of the burner. Such a problem pertaining to annular apertures can also be of relevance to other engineering applications, such as acoustic dampers or turbofan duct systems. The methodology of combining suitable acoustic Green's functions with a vortex sheet model has been applied extensively in previous theoretical studies of the acoustic response of a short circular orifice with a mean flow passing through it. In this work, the Green's function and vortex sheet model theory is generalised in order to efficiently predict the acoustic characteristics of thin annular apertures sustaining a mean flow, which effectively emulate the typical axisymmetric bluff-body burner configurations in realistic combustors. This requires the incorporation of multiple Kutta conditions for modelling the vortex shedding and multiple vortex sheets for modelling the interaction of the shed vorticity and the acoustics. A high-resolution compressible Large Eddy Simulation (LES) of a simplified representative geometry is performed for validation; the analytical prediction and numerical findings show very good agreement, and the LES further provides key insights into the speed with which vortical disturbances convect downstream. [ABSTRACT FROM AUTHOR]

The acoustic inertia of the canonical configuration of inclined circular aperture(s) in a finite-thickness plate at the low frequency limit is investigated under the inviscid still-air condition. A hybrid approach combining modal expansion and boundary element method is applied to calculate the effective length of the aperture as a quantitative characterisation of its acoustic inertia. These calculations, covering different inclination angles up to 75°, are performed for a single isolated aperture with a selected range of plate thickness and the periodic aperture arrays of aligned and staggered arrangements with a selected range of aperture spacing respectively. The results are validated by the simulations carried out with the commercial software COMSOL. The parametric studies of geometric dimensions included in this work provide representative results for typical acoustic related engineering applications of finite-length inclined apertures. A link for access to the MATLAB programmes implementing the calculations is provided for interested readers. As an example of application, the hybrid method described in this work is used for the acoustic modelling of a representative multi-perforated liner studied in the literature for the problem of thermo-acoustic instability. The results compared well against those obtained from the Computational Fluid Dynamics simulations reported in the literature. • An efficient method to compute acoustic inertia of inclined apertures is developed. • Inviscid acoustic inertia of inclined apertures in still air is studied. • Application of acoustic inertia calculation to a representative case is demonstrated. [ABSTRACT FROM AUTHOR]

One of the most important parameters influencing the acoustic response of holes that sustain a low-Mach-number bias flow is their length-to-diameter ratio. For sufficiently short holes, the bias flow is detached within the hole's length, while in long holes the bias flow reattaches. The acoustic behaviour of each class is different and separate modelling approaches exist in the literature. For many technical applications, however, the length-to-diameter ratio falls in the range 1. 5 < L h / D h < 3. 0 , where is not clear if the holes behave acoustically as short or long holes. In this work, the acoustics of such medium holes are explored numerically and analytically. The numerical approach is based on the linearisation of the compressible Navier–Stokes equations (LNSE) around a Reynolds-averaged mean flow. Medium holes are shown to whistle at higher Strouhal numbers than short holes although the mean flow reattaches within them. The underlying physics are further investigated by incorporating selected flow features of the LNSE results into a semi-analytical model accounting for vortex-sound interaction. It is shown that the perturbation field is determined by the three-way coupling of the two vortex sheets shed from the inlet and outlet edges of the hole with the acoustic field. Furthermore, the modelling of the growth of vorticity inside the hole is shown to be crucial to enable whistling in the semi-analytical model. • Short holes with reattached bias flow generate acoustic energy (whistle). • Whistling frequency significantly higher than for holes with detached bias flow. • New semi-analytical model captures the acoustics of medium holes. • Two vortex sheets shed from the hole edges couple with the acoustic field. • Shear layer instability within the hole is crucial for whistling to occur. [ABSTRACT FROM AUTHOR]

[Display omitted] The development and exploration of high-entropy materials with tunable chemical compositions and unique structural characteristics, although challenging, have attracted increasingly greater attention over the past few years. Here, we report a universal and green method to prepare high-entropy layered (oxy)hydroxide (HE-LH) nanosheets under ambient conditions. This method is based on a self-reliant electrochemical process, utilizing only low-cost metal foils and electrolytes as reactant, with no need of involving extra alkali salts and/or organic reagents. Importantly, the composition of HE-LH nanosheets is widely tunable by simply adjusting the combination of metal foils. As a representative example, quinary layered (oxy)hydroxide (CoFeNiCrV-LH) nanosheets are rationally designed, which exhibit superior electrocatalytic activity and long-term durability towards the electrocatalytic oxygen evolution reaction, outperforming both CoFe layered double hydroxides and most previously reported transition-metal-based electrocatalysts. Comprehensive characterization and analysis reveal that the high-entropy effects play a significant role in forming the defect-rich, low-crystalline microstructures, along with large specific surface areas and optimized electronic configurations, thus enabling the boosted electrocatalytic performance. This electrochemical synthetic approach is generally applicable to the scalable synthesis of diverse HE-LH materials towards versatile promising applications. [ABSTRACT FROM AUTHOR]

• Developing a new form of inversion matrix (ITDM) for moving force identification. • The two sources of error in the formation of the inversion matrix are analyzed, one is the load compression error and the other is the unit impulse response dispersion error. • The ITDM eliminates the influence of the discrete error of the unit impulse response on the load solution. • All the results have demonstrated the effectiveness of the ITDM. This paper presents a new form of inversion matrix, which aims to obtain more accurate moving force identification results from the responses of a simply supported bridge deck to vehicles passing over it. The load identification process of the modal superposition method discretizes the time-domain integral equation of the load response, obtains the load inversion matrix, and converts the load identification problem into a linear equation solving problem. The inversion matrix formation process of this traditional time domain method (TDM) can introduce the load compression error and the discretization error of the unit impulse response function, which affect the load solution. To reduce the source of error and maintain the stability of the solution, the discretized unit impulse response function is replaced by an integral form, thereby eliminating the discretization error. This method is called the integral time domain method (ITDM). A supported beam subjected to a single force and two forces is illustrated as a numerical example. Through numerical analysis, the effects of the two methods in single time-varying force identification are analyzed. Using two moving forces analysis, when noise is included, the influence of discretization error on the load solution is analyzed. Numerical results show that the discretization error has a greater impact on the load inversion using the acceleration response than the bending moment and displacement response inversion, and the ITDM should be used to avoid the interference of discrete error. [ABSTRACT FROM AUTHOR]

Sepsis, a complex clinical syndrome characterized by an exaggerated host response to infection, often necessitates hospitalization and intensive care unit admission. Delayed or inaccurate diagnosis of sepsis, coupled with suboptimal treatment strategies, can result in unfavorable outcomes, including mortality. Maresins, a newly discovered family of lipid mediators synthesized from docosahexaenoic acid by macrophages, have emerged as key players in promoting inflammation resolution and the termination of inflammatory processes. Extensive evidence has unequivocally demonstrated the beneficial effects of maresins in modulating the inflammatory response associated with sepsis; however, their bioactivity and functions exhibit remarkable diversity and complexity. This article presents a comprehensive review of recent research on the role of maresins in sepsis, aiming to enhance our understanding of their effectiveness and elucidate the specific mechanisms underlying their actions in sepsis treatment. Furthermore, emerging insights into the management of patients with sepsis are also highlighted. [Display omitted] [ABSTRACT FROM AUTHOR]

Cancer cells frequently develop resistance to chemotherapeutic therapies and targeted drugs, which has been a significant challenge in cancer management. With the growing advances in technologies in isolation and identification of natural products, the potential of natural products in combating cancer multidrug resistance has received substantial attention. Importantly, natural products can impact multiple targets, which can be valuable in overcoming drug resistance from different perspectives. In the current review, we will describe the well-established mechanisms underlying multidrug resistance, and introduce natural products that could target these multidrug resistant mechanisms. Specifically, we will discuss natural compounds such as curcumin, resveratrol, baicalein, chrysin and more, and their potential roles in combating multidrug resistance. This review article aims to provide a systematic summary of recent advances of natural products in combating cancer drug resistance, and will provide rationales for novel drug discovery. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • This work provides quantitative resolution of defect and structural vacancy sites on Al 3 O nodes of MIL-100(Al) and demonstrates the cooperative role of neighboring defect and structural vacancy sites. • Post-treatment of MIL-100(Al) with a formic acid/DMF led to replacement of ligands on defects and extra-framework BTC3- on vacancy sites by formate. • This work illustrates the chemistry of formate, methoxy and hydroxyl ligands on Al 3 O nodes. • The catalytic sites for methanol dehydation are inferred to be two adjacent sites—a defect site and its neighboring vacancy site—with methoxy reaction intermediates bonded on each site. The metal–organic framework (MOF) MIL-100, which incorporates vacancy sites on Al 3 O nodes, was synthesized with various densities of missing-benzene-1,3,5-tricarboxylate (BTC3−)-linker defect sites by using HNO 3 or acetic acid as a modulator. We report data that resolve the effects on reactivity of the node vacancies and defects that are neighbors of each other. For example, extra-framework BTC3− ligands were bonded to one vacancy site per node, and modulator-derived NO 3 − and acetate ligands were bonded in various ratios to defect sites. In reactions with formic acid, these ligands were replaced with monodentate and bidentate formates. The ligands on defects were found to be more reactive than those on vacancies. The MOF was used to catalyze methanol dehydration at 220 °C and 1 bar in a flow reactor, and the catalytic activity increased with increasing numbers of defects and with replacement of extra-framework BTC3- with formate. Catalysis started as methanol reacted with formate ligands to form methyl formate, which desorbed, leaving methoxy groups on the nodes—and these became catalytic reaction intermediates. IR spectra and catalyst performance data show that that catalysis proceeds as bidentate methoxy bonded to a defect site reacts with monodentate methoxy bonded to a neighboring vacancy site. Having a high density of these paired sites, MIL-100(Al) is markedly more active catalytically than the MOF MIL-53, in which these essential sites are mostly isolated. Deactivation of MIL-100 during catalysis resulted from self-inhibition, as bidentate methoxy ligands were replaced with μ 2 -OH ligands formed from water produced in the dehydration reaction. The results highlight the role of pair sites on MOF nodes for catalyzing a reaction that involves a bimolecular step, indicating how to control the catalytic sites. We thus foresee opportunities to tailor MOF catalytic properties for reactions involving various numbers of catalytic sites on the nodes. [ABSTRACT FROM AUTHOR]

Acetaminophen (APAP) overdose is a major cause of acute liver failure, while the underlying mechanisms of APAP hepatotoxicity are not fully understood. Recently, emerging evidence suggests that epigenetic enzymes play roles in APAP-induced liver injury. Here, we found that Utx (ubiquitously transcribed tetratricopeptide repeat, X chromosome, also known as KDM6A), a X-linked histone demethylase which removes the di- and tri-methyl groups from histone H3K27, was markedly induced in the liver of APAP-overdosed female mice. Hepatic deletion of Utx suppressed APAP overdose-induced hepatotoxicity in female but not male mice. RNA-sequencing analysis suggested that Utx deficiency in female mice upregulated antitoxic phase II conjugating enzymes, including sulfotransferase family 2 A member 1 (Sult2a1), thus reduces the amount of toxic APAP metabolites in injured liver; while Utx deficiency also alleviated ER stress through downregulating transcription of ER stress genes including Atf4 , Atf3 , and Chop. Mechanistically, Utx promoted transcription of ER stress related genes in a demethylase activity-dependent manner, while repressed Sult2a1 expression through mediating H3K27ac levels independent of its demethylase activity. Moreover, overexpression of Sult2a1 in the liver of female mice rescued APAP-overdose induced liver injury. Together, our results indicated a novel UTX-Sult2a1 axis for the prevention or treatment of APAP-induced liver injury. [Display omitted] • Utx is induced in the liver of female mouse upon APAP overdose. • Loss of Utx suppresses APAP-induced liver injury in female but not male mouse. • Utx gender-specifically regulates antitoxic phase II conjugating enzyme Sult2a1. • Utx demethylase-dependently induces ER stress and represses Sult2a1 independently. • Overexpression of Sult2a1 rescues APAP-induced hepatotoxicity in female mouse. [ABSTRACT FROM AUTHOR]

[Display omitted] Self-assembly of colloidal nanoparticles (NPs) into well-defined superstructures has been recognized as one of the most promising ways to fabricate rationally-designed functional materials for a variety of applications. Introducing hierarchical mesoporosity into NP superstructures will facilitate mass transport while simultaneously enhancing the accessibility of constituent NPs, which is of critical importance for widening their applications in catalysis and energy-related fields. Herein, we develop a colloidal co-assembly strategy to construct mesostructured, carbon-coated Co 0.5 Fe 2.5 O 4 NP superstructures (M-C@CFOSs), which show great promise as highly efficient electrocatalysts for the oxygen evolution reaction (OER). Specifically, organically-stabilized SiO 2 NPs are employed as both building blocks and sacrificial template, which co-assemble with Co 0.5 Fe 2.5 O 4 NPs to afford binary NP superstructures through a solvent drying process. M-C@CFOSs are obtainable after in situ ligand carbonization followed by the selective removal of SiO 2 NPs. The hierarchical mesoporous structure of M-C@CFOSs, combined with the conformal graphitic carbon coating derived from the native organic ligands, significantly improves their electrocatalytic performance as OER electrocatalysts when compared with nonporous Co 0.5 Fe 2.5 O 4 NP superstructures. This work establishes a new and facile approach for designing NP superstructures with hierarchical mesoporosity, which may find wide applications in energy storage and conversion. [ABSTRACT FROM AUTHOR]

A new method relying on machine learning and resistivity to predict concentrations of petroleum hydrocarbon pollution in soil was proposed as a means of investigation and monitoring. Currently, determining pollutant concentrations in soil is primarily achieved through costly sampling and testing of numerous borehole samples, which carries the risk of further contamination by penetrating the aquifer. Additionally, conventional petroleum hydrocarbon geophysical surveys struggle to establish a correlation between survey results and pollutant concentration. To overcome these limitations, three machine learning models (KNN, RF, and XGBOOST) were combined with the geoelectrical method to predict petroleum hydrocarbon concentrations in the source area. The results demonstrate that the resistivity-based prediction method utilizing machine learning is effective, as validated by R-squared values of 0.91 and 0.94 for the test and validation sets, respectively, and a root mean squared error of 0.19. Furthermore, this study confirmed the feasibility of the approach using actual site data, along with a discussion of its advantages and limitations, establishing it as an inexpensive option to investigate and monitor changes in petroleum hydrocarbon concentration in soil. • The prediction of soil petroleum hydrocarbon concentration is achieved by machine learning and resistivity tomography method. • Building the mapping relationship between soil petroleum hydrocarbon pollution concentration and resistivity. • External validation data verify feasibility of predicting soil petroleum hydrocarbon contamination concentrations based on resistivity. [ABSTRACT FROM AUTHOR]

Beauvericin is a world-spread mycotoxin isolated from the traditional Chinese medicine, Bombyx batryticatus (BB), which has been widely used to treat various neoplastic diseases. This study investigated the anti-hepatocellular carcinoma (HCC) activity of beauvericin and its potential mechanism. In this study, H22-bearing mice were intraperitoneally injected with 3, 5, 7 mg/kg of beauvericin once per-week over a three-week period. TUNEL staining determined the extent of tumor apoptosis induced by beauvericin. ELISA kits detected the level of IL-2, Perforin, and TNF-α, IFN-γ level in the serum. H22 hepatoma cells were exposed to beauvericin (5, 10, and 20 μmol/L) to investigate the underlying pathway. CCK-8 assay was used to observe the influence of beauvericin on the growth of H22 cells. Flow cytometry was used to detect the cell apoptosis and ROS level. Western blotting was performed to detect apoptotic and PI3K/AKT pathway protein production. The results showed that beauvericin could remarkably inhibit the growth of HCC in mice, combined with elevated TNF-α and IL-2. In vitro , beauvericin significantly promoted the generation of ROS, up-regulated Bax/Bcl-2 ratio and cleaved caspase-9, cleaved caspase-3 levels, down-regulated p-PI3K/PI3K ratio, p-AKT/AKT ratio, promoted the apoptosis of H22 cells, and inhibited the growth of H22 cells. Remarkably, treatment with PI3K/AKT activator (740Y–P and SC79) could prevent beauvericin-induced H22 cell apoptosis. These findings collectively indicate that beauvericin inhibits HCC growth by inducing apoptosis via the PI3K/AKT pathway. [Display omitted] • Beauvericin is a world-spread mycotoxin isolated from the traditional Chinese medicine, Bombyx batryticatus (BB). • Beauvericin can suppress hepatocellular carcinoma (HCC) development in vivo and in vitro. • Beauvericin inhibits HCC growth by inducing PI3K/AKT-mediated apoptosis. • Beauvericin could be further investigated as a potential cytotoxic natural compound for the treatment of HCC. [ABSTRACT FROM AUTHOR]

Changes in land use and landscapes have a direct impact on the regional eco-environment. It is of great importance to understand the change pattern of land use, landscapes, and their mechanism on the ecological quality, especially ecologically fragile areas. The northern sand-prevention belt (NSPB) is an important ecologically fragile area in China, which has a large influence on the ecological security of the entire country. Based on the land use data of the NSPB in 2000, 2010, and 2018, we studied the spatio-temporal characteristics of land-use change and change in landscape patterns. The ecological quality represented by the remote sensing-based desertification index (RSDI) was calculated using satellite images. The effects of land use and landscape patterns on RSDI were analyzed by geographic detector and geographically weighted regression. Important results include the following: (1) Land-use change in the study area was high during 2000–2010 but slower in 2010–2018. Grassland was the largest land-use type in the NSPB, and varied greatly in terms of total change and spatial location. The major change was the conversion between dense and moderate grass, with 64,860 km2 of dense grass turning into moderate grass, and 48,505 km2 changing the other way. (2) Among the four landscape metrics, patch density, area-weighted mean fractal dimension, and edge density increased, whereas the aggregation index decreased, which indicated that the landscape was developing towards heterogeneity, fragmentation, complexity, and aggregation. Spatially, the landscape metrics presented a strip distribution in the east of the NSPB. (3) The effects of various land-use types on ecological quality, from high to low, were unused land, woodland, dense grass, cropland, moderate grass, built-up land, sparse grass, and waterbody. The areas where the ecological quality was greatly affected by the landscape patterns were concentrated in the agro-pastoral ecotone and the forest-steppe ecotone. The results of this study reveal the trends of land use and landscape patterns in the NSPB over 18 years and can help to understand their mechanism on ecological quality, which is of significance for the management of this area. • LUC in the NSPB was active from 2000 to 2010 and weakened from 2010 to 2018. • The landscape was developing towards heterogeneity, fragmentation, complexity, and aggregation. • The effects of land use and landscape on ecological quality were studied by GD and GWR. [ABSTRACT FROM AUTHOR]

Airway hyperresponsiveness (AHR) is a clinical manifestation of airflow limitation due to abnormal tracheal and bronchial sensitivity and is the main basis for the diagnosis of asthma. Patients with AHR are at high risk of perioperative tracheal and bronchospasm, which can lead to hypoxaemia and haemodynamic instability and, in severe cases, to a life-threatening 'silent lung'. It is therefore important to reduce the incidence or intensity of AHR episodes in the perioperative period. The inflammatory response is key to the development and progression of AHR. Based on the modulatory role of dexmedetomidine (DEX) in the inflammatory response, we hypothesised that dexmedetomidine (DEX) attenuates inflammatory properties by inhibiting the toll-like receptor 4 (TLR4)/nuclear factor (NF-κB) signalling pathway and can reduce the respiratory parameters of mechanical ventilation in ovalbumin-induced allergic airway hyperresponsiveness. BABL/C mice were divided into control and OVA groups (ovalbumin-induced allergy. Ten mice in all OVA models were randomly selected for in vivo invasive lung function monitoring to analyse airway resistance parameters and demonstrate successful model establishment. The remaining OVA mice were treated with dexmedetomidine 25 μg/kg for 5 days (OVA + DEX group) or dexmedetomidine 25 μg/kg + yohimbine 1 mg/kg for 5 days (OVA + DEX + yohimbine). After treatment, bronchoalveolar lavage fluid (BAL) and peripheral blood (ELISA) and lung tissue (H&E and PAS) were collected for analysis of inflammatory factors, and lung tissue was verified by PCR for genes and proteins that do correlate with inflammatory mediators. All airway resistance parameters were increased in OVA mice by invasive lung function monitoring. Proximal airway resistance (parameter Rn) and total respiratory resistance (parameter Rrs) were attenuated after dexmedetomidine intervention treatment. Dexmedetomidine reduced total inflammatory cell count and inflammatory infiltration of lung tissue in BALF and down-regulated IL-4 and IgE levels in BALF and peripheral blood, as shown by Giemsa, H&E, PAS staining and ELISA; this mechanism of action was found to be related to the TLR4/NFκB pathway, but not to TLR4/NFκB, as measured by PCR. Dexmedetomidine reduces hyperresponsiveness and airway inflammatory responses. This mechanism of action may be related to the TLR4/NFκB signalling pathway. Overall conclusions are presented in. [ABSTRACT FROM AUTHOR]

Heat exchanger tube rows can influence the thermoacoustic instability behaviour of combustion systems since they act as both acoustic scatterers and unsteady heat sinks. Therefore, with careful tuning of their thermoacoustic properties, heat exchangers have the potential to act as passive control devices. In this work, we focus on (only) the acoustic scattering behaviour of heat exchanger tubes. We present a comparison of existing acoustic models for tube rows and slits, models for the latter having the advantage of incorporating frequency dependence. We then propose a new model that enables the adaptation of slit models for tube rows. This model is validated against experiments and Linearised Navier–Stokes Equations (LNSE) predictions for the transmission and reflection coefficients, including phase information. The model predictions show very good agreement with the experimental and numerical validations, especially for low frequencies (Strouhal number < 0. 5 , based on tube radius and excitation frequency), with mean differences less than 2% for the transmission coefficients (the reflection coefficient errors are somewhat larger since their magnitudes are very close to zero). [ABSTRACT FROM AUTHOR]

Hexarelin, a synthetic growth hormone-releasing peptide, is shown to be protective in cardiovascular diseases such as myocardial infraction and atherosclerosis. However, the functional role of hexarelin in abdominal aortic aneurysm (AAA) remains undefined. The present study determined the effect of hexarelin administration (200 μg/kg twice per day) in a mouse model of elastase-induced abdominal aortic aneurysm. Echocardiography and in situ pictures showed hexarelin decreased infrarenal aorta diameter. Histology staining showed elastin degradation was improved in hexarelin-treated group. Hexarelin rescued smooth muscle cell contractile phenotype with increased α-SMA and decreased MMP2. Furthermore, hexarelin inhibited inflammatory cell infiltration, NLRP3 inflammasome activation and IL-18 production. Particularly, hexarelin suppressed NF-κB signaling pathway which is a key initiator of inflammatory response. These results demonstrated that hexarelin attenuated AAA development by inhibiting SMC phenotype switch and NF-κB signaling mediated inflammatory response. • Hexarelin treatment attenuated elastase-induced AAA formation. • Hexarelin rescued SMC contractile phenotype to attenuate AAA formation. • Hexarelin ameliorated inflammatory response in AAA. • Hexarelin suppressed the activation of NLRP3 inflammasome via NF-κB mediated signaling. [ABSTRACT FROM AUTHOR]