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Multi-layer slopes are widely found in clay residue receiving fields. A generalized horizontal slice method (GHSM) for assessing the stability of multi-layer slopes that considers the energy dissipation between adjacent horizontal slices is presented. In view of the upper-bound limit analysis theory, the energy equation is derived and the ultimate failure mode is generated by comparing the sliding surface passing through the slope toe (mode A) with that below (mode B). In addition, the influence of the number of slices on the stability coefficients in the GHSM is studied and the stable value is obtained. Compared to the original method (Chen's method), the GHSM can acquire more precise results, which takes into account the energy dissipation in the inner sliding soil mass. Moreover, the GHSM, limit equilibrium method (LEM) and numerical simulation method (NSM) are applied to analyze the stability of a multi-layer slope with different slope angles and the results of the safety factor and failure mode are very close in each case. The ultimate failure modes are shown to be mode B when the slope angle is not more than 28°. It illustrates that the determination of the ultimate sliding surface requires comparison of multiple failure modes, not only mode A. [ABSTRACT FROM AUTHOR]

In this study, we synthesized solid solutions of x Bi(Ni 1/2 Hf 1/2)O 3 -(1 − x)PbTiO 3 (x BNH-PT) with the aim of elucidating their phase boundary behaviors and the associated physical properties. A tetragonal (T) - pseudocubic (PC) phase boundary was confirmed at x = 0.38. For x = 0.36 and x = 0.37 with distinct tetragonal distortions, a spontaneous ferroelectric-relaxor transition was observed. The introduction of a T-PC phase boundary not only led to enhanced piezoelectric properties (d 33 = 456 pC/N, x = 0.39) but also effectively suppressed the spontaneous ferroelectric-relaxor transition. Detailed analysis revealed that the local structure of the initial state in 0.39BNH-0.61PT remained tetragonal. After poling, a long-range tetragonal phase was formed from the short-range tetragonal clusters, with the c/a value of ∼1.01. Our observations of frequency dispersion strongly suggest the presence of local inhomogeneities, resulting in distinct poling effects on the dielectric and elastic behaviors of the material. ● The onset of a T-PC phase boundary could enhance piezoelectric properties and suppress the spontaneous F-R transition. ● The poling field promoted the formation of a long-range T phase from the short-range T clusters in 0.39BNH-0.61PT. ● The presence of the local inhomogeneities gave different poling effects on the dielectric and elastic behaviors. [ABSTRACT FROM AUTHOR]

Background: Dystonia is a condition that affects the ability to control the movement and function of the body's muscles. It can cause not only physical problems, but also mental problems, resulting in impaired health-related quality of life (HRQoL). However, the effect of deep brain stimulation on quality of life in acquired dystonia remains unclear. Methods: We conducted a systematic literature review from January 2000 to October 2022，determined the eligible studies, and performed a meta-analysis of HRQoL outcomes based on the Short-Form Health Survey-36 (SF-36) after DBS to evaluate the effects of DBS on physical and mental QoL. Results: A total of 14 studies met the inclusion criteria and were systematically reviewed. A comprehensive meta-analysis was performed for 9 studies that reported physical and psychological data or physical component summary (PCS), or mental component summary (MCS) for SF-36. The mean (SD) age at DBS implantation was 34.29 (10.3) years, and the follow-up period after implantation was 2.21 (2.80) years. The random effects model meta-analysis revealed that both physical and mental domains of the SF-36 improved following DBS. There was no statistically significant difference between the physical domains (effect size=1.34; p<0.0001) and the mental domains (effect size=1.38; p<0.0001). Conclusion: This is the first meta-analysis that demonstrates significant benefits in HRQoL following DBS in patients with acquired dystonia. There were significant improvements in both physical QoL and mental QoL. [ABSTRACT FROM AUTHOR]

In the post-genome era, great progress has been made in metabolic engineering using recombinant DNA technology to enhance the production of high-value products by Streptomyces. With the development of microbial genome sequencing techniques and bioinformatic tools, a growing number of secondary metabolite (SM) biosynthetic gene clusters in Streptomyces and their biosynthetic logics have been uncovered and elucidated. In order to increase our knowledge about transcriptional regulators in SM of Streptomyces, this review firstly makes a comprehensive summary of the characterized factors involved in enhancing SM production and awakening SM biosynthesis. Future perspectives on transcriptional regulator engineering for new SM biosynthesis by Streptomyces are also provided. [ABSTRACT FROM AUTHOR]

Background: A growing number of studies have demonstrated that the polar regions have the potential to be a significant repository of microbial resources and a potential source of active ingredients. Genome mining strategy plays a key role in the discovery of bioactive secondary metabolites (SMs) from microorganisms. This work highlighted deciphering the biosynthetic potential of an Arctic marine-derived strain Aspergillus sydowii MNP-2 by a combination of whole genome analysis and antiSMASH as well as feature-based molecular networking (MN) in the Global Natural Products Social Molecular Networking (GNPS). Results: In this study, a high-quality whole genome sequence of an Arctic marine strain MNP-2, with a size of 34.9 Mb was successfully obtained. Its total number of genes predicted by BRAKER software was 13,218, and that of non-coding RNAs (rRNA, sRNA, snRNA, and tRNA) predicted by using INFERNAL software was 204. AntiSMASH results indicated that strain MNP-2 harbors 56 biosynthetic gene clusters (BGCs), including 18 NRPS/NRPS-like gene clusters, 10 PKS/PKS-like gene clusters, 8 terpene synthse gene clusters, 5 indole synthase gene clusters, 10 hybrid gene clusters, and 5 fungal-RiPP gene clusters. Metabolic analyses of strain MNP-2 grown on various media using GNPS networking revealed its great potential for the biosynthesis of bioactive SMs containing a variety of heterocyclic and bridge-ring structures. For example, compound G-8 exhibited a potent anti-HIV effect with an IC50 value of 7.2 nM and an EC50 value of 0.9 nM. Compound G-6 had excellent in vitro cytotoxicities against the K562, MCF-7, Hela, DU145, U1975, SGC-7901, A549, MOLT-4, and HL60 cell lines, with IC50 values ranging from 0.10 to 3.3 µM, and showed significant anti-viral (H1N1 and H3N2) activities with IC50 values of 15.9 and 30.0 µM, respectively. Conclusions: These findings definitely improve our knowledge about the molecular biology of genus A. sydowii and would effectively unveil the biosynthetic potential of strain MNP-2 using genomics and metabolomics techniques. [ABSTRACT FROM AUTHOR]

A novel in-situ TiB 2 /FeMnAl metal matrix composites with different Mn content have been prepared and characterized. The effects of the Mn content on the microstructure evolution and performances were discussed. In all fabricated FeMnAl metal matrix composites, the in-situ TiB 2 particles were dispersedly distributed in austenite matrix after hot rolling and annealing. Significantly, no eutectic M 2 B (M = Fe, Mn) boride formed along grain boundaries in all composites that shows the excellent hot workability. The tensile strength and elongation after fracture of the all composite above 20 wt% Mn are more than 750 MPa and 12 % at room temperature, respectively. The ultimate tensile strength of composites with 20 wt% Mn can maintain above 560 MPa at 500 °C. The shielding properties was also investigated by Monte Carlo method, and this designed composites are expected to be well materials for practical application. [Display omitted] • Successfully manufactured novel TiB 2 /FeMnAl composites and TiB 2 particles are dispersedly distributed in the matrix. • No eutectic M 2 B borides can be found in fabricated composites makes composites possess excellent hot workability. • The fabricated composites have excellent combination of ductility and strength at room temperature. • The ultimate tensile strength of fabricated composites can maintain above 560 MPa at 500 °C. [ABSTRACT FROM AUTHOR]

Background: Chrysomycin A (CA) is a promising antibiotic for treatment of Gram-positive bacterial infections and cancers. In order to enhance CA yield, optimization of fermentation conditions and medium components was carried out on strain Streptomyces sp. 891-B6, an UV-induced mutant with improved CA titer compared with its wide-type marine strain 891. Results: Using one-way experiment, the optimal fermentation conditions for CA production in 1-L shake flask were obtained as follows: 12 days of fermentation time, 5 days of seed age, 5% of inoculum volume ratio, 200 mL of loading volume and 6.5 of initial pH. By response surface methodology, the optimal medium components determined as glucose (39.283 g/L), corn starch (20.662 g/L), soybean meal (15.480 g/L) and CaCO3 (2.000 g/L). Conclusion: Validation tests showed that the maximum yield of CA reached 1601.9 ± 56.7 mg/L, which was a 60% increase compared to the initial yield (952.3 ± 53.2 mg/L). These results provided an important basis for scale-up production of CA by strain 891-B6. [ABSTRACT FROM AUTHOR]

Bacterial virulence factors and biofilm development can be controlled by the quorum-sensing (QS) system, which is also intimately linked to antibiotic resistance in bacteria. In previous studies, many researchers found that quorum-sensing inhibitors (QSIs) can affect the development of bacterial biofilms and prevent the synthesis of many virulence factors. However, QSIs alone have a limited ability to suppress bacteria. Fortunately, when QSIs are combined with antibiotics, they have a better therapeutic effect, and it has even been demonstrated that the two together have a synergistic antibacterial effect, which not only ensures bactericidal efficiency but also avoids the resistance caused by excessive use of antibiotics. In addition, some progress has been made through in vivo studies on the combination of QSIs and antibiotics. This article mainly expounds on the specific effect of QSIs combined with antibiotics on bacteria and the combined antibacterial mechanism of some QSIs and antibiotics. These studies will provide new strategies and means for the clinical treatment of bacterial infections in the future. [ABSTRACT FROM AUTHOR]

Fungal non-ribosomal peptide synthetase (NRPS)-encoding products play a paramount role in new drug discovery. Fusarium, one of the most common filamentous fungi, is well-known for its biosynthetic potential of NRPS-type compounds with diverse structural motifs and various biological properties. With the continuous improvement and extensive application of bioinformatic tools (e.g., anti-SMASH, NCBI, UniProt), more and more biosynthetic gene clusters (BGCs) of secondary metabolites (SMs) have been identified in Fusarium strains. However, the biosynthetic logics of these SMs have not yet been well investigated till now. With the aim to increase our knowledge of the biosynthetic logics of NPRS-encoding products in Fusarium, this review firstly provides an overview of research advances in elucidating their biosynthetic pathways. [ABSTRACT FROM AUTHOR]

Anaerobic digestion technology has gained significant attention as an organic solid waste treatment method due to its favorable economic and environmental benefits. However, after digestion, the digestate still contains a significant amount of underutilized organic matter. Sustainable management and resource utilization of digestate plays a crucial role in achieving resource circularity and implementing a circular economy. Previous reviews have mainly focused on improving the operational efficiency and stability of anaerobic digestion, with limited exploration of sustainable management and resource utilization of digestate. To address this gap, this review provides a systematic summary of the sustainable management and resource utilization of digestate. First, the basic characteristics of digestate are outlined. Then, based on a visual analysis of literature on digestate management from the past decade, the review highlights the hotspots in sustainable management and circular utilization of digestate. Finally, it summarizes the relevant policies on digestate management in different regions and outlines the challenges in digestate treatment and disposal. The challenges in digestate management remain a significant issue that requires further exploration and solutions. This review aims to promote the standardization of digestate management, provide direction for further in-depth research on digestate, and contribute to the continued development of resource cycling of anaerobic fermentation products. [Display omitted] [ABSTRACT FROM AUTHOR]

SUMMARY: Sorghum is an important crop for food, forage, wine and biofuel production. To enhance its transformation efficiency without negative developmental by‐effects, we investigated the impact of GRF4‐GIF1 chimaera and GRF5 on sorghum transformation. Both GRF4‐GIF1 and GRF5 effectively improved the transformation efficiency of sorghum and accelerated the transformation process of sorghum to less than 2 months which was not observed when using BBM‐WUS. As agrobacterium effectors increase the ability of T‐DNA transfer into plant cells, we checked whether ternary vector system can additively enhance sorghum transformation. The combination of GRF4‐GIF1 with helper plasmid pVS1‐VIR2 achieved the highest transformation efficiency, reaching 38.28%, which is 7.71‐fold of the original method. Compared with BBM‐WUS, overexpressing GRF4‐GIF1 caused no noticeable growth defects in sorghum. We further developed a sorghum CRISPR/Cas9 gene‐editing tool based on this GRF4‐GIF1/ternary vector system, which achieved an average gene mutation efficiency of 41.36%, and null mutants were created in the T0 generation. Significance Statement: An accelerated and efficient transformation strategy of sorghum was established which has 38.28% efficiency in less than 2 months. The regenerated plants showed no growth defect. [ABSTRACT FROM AUTHOR]

This study investigated a dynamic stability analytical model for bedding rock slope with soil interlayer, considering various rain patterns. The critical rain intensities for anhydrous and water-filled fissure were derived, respectively. Rain coefficients (i.e., concentration and peak position coefficients) were subsequently introduced to investigate rain patterns. The evolving water head under different infiltration scenarios was derived based on Darcy's law and mass conversation law. Additionally, the time-varying water pressure along soil interlayer was obtained based on triangular distribution assumption. An analytical model incorporating time-varying water head was established to predict slope stability based on limit equilibrium method. Numerical simulations further validated the analytical solutions for time-varying water head and pressure. The evolving characteristic of slope stability was analyzed, and a failure threshold was proposed. Results demonstrated that rain patterns and rain coefficients significantly impact on the rainfall threshold corresponding to slope failure. For uniform rain-induced slope failure, rainfall threshold tends to increase as rain intensity decreases. For unimodal rain-induced slope failure, the rainfall threshold is the largest for post-peak rain corresponding to slope failure, followed by the medium-peak rain, and the smallest for forward-peak rain. These results and findings enhance our understanding of the dynamic stability of bedding rock slope with inclined soil interlayer and provide valuable insights into assessing the evolving slope stability under different rain patterns. Highlights: An analytical model of dynamic slope stability coupling time-varying water head was established. Impacts of rain pattern and rainfall intensity on slope stability were systematically investigated. Rainfall threshold for slope failure considering different rain patterns was proposed based on analytical model. 〹 [ABSTRACT FROM AUTHOR]

We employ a sample of 135 873 RR Lyrae stars (RRLs) with precise photometric-metallicity and distance estimates from the newly calibrated P –ϕ31– R 21–[Fe/H] and Gaia G band P – R 21–[Fe/H] absolute magnitude–metallicity relations of Li et al. combined with available proper motions from Gaia EDR3, and 6955 systemic radial velocities from Gaia DR3 and other sources, in order to explore the chemistry and kinematics of the halo of the Milky Way (MW). This sample is ideally suited for characterization of the inner- and outer-halo populations of the stellar halo, free from the bias associated with spectroscopically selected probes, and for estimation of their relative contributions as a function of Galactocentric distance. The results of a Gaussian mixture model analysis of these contributions are broadly consistent with other observational studies of the halo, and with expectations from recent MW simulation studies. We apply the hdbscan clustering method to the specific energies and cylindrical actions (E , Jr, Jϕ, J z ), identifying 97 dynamically tagged groups (DTGs) of RRLs, and explore their associations with recognized substructures of the MW. The precise photometric-distance determinations (relative distance errors on the order of 5 per cent or better), and the resulting high-quality determination of dynamical parameters, yield highly statistically significant (low) dispersions of [Fe/H] for the stellar members of the DTGs compared to random draws from the full sample, indicating that they share common star-formation and chemical histories, influenced by their birth environments. [ABSTRACT FROM AUTHOR]

Although the catalytic pyrolysis of low-density polyethylene (LDPE) to produce light olefin has shown potential industrial application advantages, it has generally suffered when using higher pyrolysis temperatures. In this work, Mg-modified Fe-ZSM-5 was used for catalytic conversion of LDPE to obtain light olefin in a fixed bed reactor. The effects of catalyst types, pyrolysis temperatures, and Mg loading on the yield of light olefin were investigated. The 1 wt% Mg loading slightly improved the yield of light olefin to 38.87 wt% at 395 °C, lowering the temperature of the pyrolysis reaction. We considered that the higher light olefin yield of Fe-Mg-ZSM-5 was attributed to the introduction of Mg, where Mg regulated the surface acidity of the catalyst, inhibited the secondary cracking reaction, and reduced coking during the pyrolysis process. Furthermore, the addition of Mg also dramatically reduced the average particle size of Fe oxides from 40 nm to 10 nm, which is conducive to a lower catalytic reaction temperature. Finally, the spent catalyst could be easily regenerated at the conditions of 600 °C in airflow with a heating rate of 10 °C/min for 1 h, and the light olefin yield remained higher than 36.71 wt% after five cycles, indicating its excellent regeneration performance. [ABSTRACT FROM AUTHOR]

Bio-based aerogels are sustainable and eco-friendly materials that have gained increasing attention. However, their development is hindered by complex technological processes and unsatisfactory mechanical properties. To obtain a multi-scale hierarchical micro-meso porous composite aerogel with extraordinary thermal insulation and mechanical properties via simple and facile preparation process, we used oxidized cotton linter fiber (CF) as the skeleton and reinforcement, oxidized microcrystalline cellulose (MCC) as the supporting and filling matrix, and PVA as the crosslinking agent and a good glue to enhance the interaction between CF and MCC, and the porous network of the composite aerogel. The composite aerogel is very light, strong, and flexible. The best obtained composite aerogel has a apparent density of only 67.5% of the pure cotton fiber composite aerogel (CF 0), a maximum compressive stress of 1.22 MPa, which is 22 times higher than the pure microcrystalline composite aerogel (MCC 0), and a thermal conductivity of 0.0335 W/m.K, which is 89% lower than CF 0. These properties make the composite aerogel suitable for various thermal insulation applications, such as protective clothing for extremely cold environment. [Display omitted] • Cotton linter composite aerogels were facilely prepared in an environmental-friendly strategy. • The composite aerogels have a multi-scale hierarchical micro-meso structure with enhanced hydrogen bonding. • The composite aerogels have enhanced mechanical properties and thermal insulation. [ABSTRACT FROM AUTHOR]

Co-abatement strategies that can reduce both CO 2 and air pollutants emissions are essential for the green and low-carbon transition of China's iron and steel industry. Most previous studies analyzed CO 2 and air pollutants reduction policies independently, but the synergies and tradeoffs between the two types of policies have rarely been investigated. By establishing a bottom-up simulation model that considers combinations of different policy objectives, crude steel demand and technology development options, this study couples air pollutants reduction into the carbon neutrality pathways to evaluate the synergistic effects of different abatement strategies in China's iron and steel industry. The study also incorporates the indirect CO 2 and air pollutants emissions from the upstream energy production sectors into pathway analysis, in order to avoid cross-sectoral carbon and air pollution leakages. The results show that the current emissions reduction policies in the iron and steel industry are far from achieving the carbon neutrality goals. To achieve synergistic reduction in CO 2 and air pollutants emissions, the short term policies should mainly rely on increasing the share of the scrap-electric arc furnace (EAF), while reducing crude steel demand and promoting breakthrough technologies, particularly hydrogen-based direct reduction, should play a major role in the long term. Meanwhile, China should promote the decarbonization of power generation and hydrogen production to reduce indirect CO 2 and air pollutants emissions from the upstream sectors. [Display omitted] • Explore pathways for CO 2 and air pollutants co-abatement in iron and steel industry. • Evaluate contributions and synergistic effects of different abatement strategies. • Stronger policy measures are needed to achieve carbon neutrality target. • Decarbonization of upstream energy sectors is critical to reduce indirect emissions. • Material efficiency and structural adjustment have greater synergistic effects. [ABSTRACT FROM AUTHOR]

The ZrO 2 -Al 2 O 3 composite coatings were fabricated on TiB 2 /2024Al composite by the plasma electrolytic oxidation (PEO) treatment with either monoclinic (m -ZrO 2) or tetragonal zirconia (t -ZrO 2) nanoparticles (NPs) addition. Such PEO coatings showed a double layer morphology due to the limited physical motion ability of ZrO 2 colloidal particles into coatings. t -ZrO 2 remained as the main phase in ZrO 2 -Al 2 O 3 PEO composite coatings whether t -ZrO 2 or m -ZrO 2 NPs were added. Based on the microstructure analyses by focus ion beam plus scanning electron microscopy and transmission electron microscopy, ZrO 2 showed netlike morphology in the outer layer with NPs partially melted at the mesh boundary and lines-like morphology fully melted at the inner mesh in the coating. A prominent morphological transition of ZrO 2 was clearly observed at the interface between outer layer and inner layer. Therefore, the continuous growth mechanisms of ZrO 2 -Al 2 O 3 composite PEO coatings were proposed in terms of morphological evolution process. Furthermore, electrochemical measurements and cavitation erosion tests were conducted to study the comprehensive surface properties (corrosion and impact resistance) of ZrO 2 -Al 2 O 3 composite coatings. As a result, the ZrO 2 -Al 2 O 3 composite PEO coatings with m -ZrO 2 addition exhibited the greatly reduced corrosion rate, and superior cavitation erosion resistance. Accordingly, the underlying mechanisms for these improved properties were intensively discussed. • Differences between m -ZrO 2 and t -ZrO 2 additives were discussed. • Morphological features of ZrO 2 in PEO coating were characterized by FIB-SEM and TEM. • Continuous growth mechanisms of PEO coatings were proposed in terms of the morphological evolution process. • The as-fabricated PEO coating showed superior corrosion and cavitation erosion resistance. [ABSTRACT FROM AUTHOR]