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Freight transport with heavy trucks has emerged as a significant energy-intensive sector and a major contributor to carbon emissions in China's transportation industry. The diesel consumption in this field represents approximately 40 % of China's total annual diesel consumption, while the CO2 emissions account for approximately 50 % of the total annual CO2 emissions in the transportation industry. Under the background of carbon peaking and carbon neutrality goals and energy revolution, it has become an inevitable trend to build a green, secure and efficient road freight mode and promote the low-carbon and clean transformation of heavy freight transport. So far, the electrification options of freight transport with heavy trucks mainly include charging, battery swapping, hydrogen heavy trucks, and electrified highways. This paper mainly introduces the hydrogen heavy truck and electrified highway options. Based on a dedicated coal transport route, the economic efficiency and application scenarios were compared and analyzed between these two options from a perspective of cost estimates. The analysis results show that, for this dedicated coal transport route, when the annual traffic volume is greater than 2.0483 million tons, the electrified highway option is more economical, while on the contrary, the cost of the hydrogen heavy truck option is lower.

one support frame was designed for the independent suspension of 8 × 8 off road chassis,on purpose of that connect two suspension brackets. The frame was damaged after vehicle enhance road test with the weld seam cracked and the bolt cut off. According to the failure performance,the model about independent suspension included support frame was built for failure analysis,and the failure was caused by uncoordinated deformation of different parts; the support frame is improved and verified by simulation and test.

The high power transfer case as a key component of a multi-axis super-heavy chassis transmission system,with the characteristics of large torque,high speed,and large temperature difference,rely on splash lubrication and natural air cooling has been unable to meet the need of the chassis for high mobility,high through off-road and extreme ambient temperature. It is necessary to use the forced lubrication system to lubricate the internal hot spots of the transfer case,especially the bearing position. Therefore,the power thermal energy model of the hotspots of the transmission parts is built first,through the heat balance conditions,the flow demand of the lubrication point and the overall are estimated,and then a hydraulic simulation analysis model is established,the matching lubrication system piping is designed. Aiming at the problem of the natural air cooling can’t achieve the system thermal balance requirements in the great power of the transmission system,by calculating the surface wind speed and heat dissipation surface,the heat dissipation capacity of the transfer case itself is evaluated,the external air-cooled radiator and fan are matched according to the heat dissipation requirement.Finally,through the bench and running vehicle test,the design of the high power transfer case forced lubrication system to meet a multi-axis super-heavy chassis of the use of the requirements is verified.

Aiming at the structure of transmission case housing used in electric vehicle,the topology optimization analysis of transmission case housing used in electric vehicle,including the external and internal reinforcing plates and outside profile is conducted by using the method of topology optimization analysis from the forward design. In the optimization,the minimum weighted compliance is set as the optimization objective and volume fraction,displacement,stress,modal frequency and machining technology as constrains. Based on the topology optimization result,the optimization design of transmission case housing is carried out with considering the requirements of assembly,lubrication and cooling. Furthermore,the stresses state and modal frequency of the transmission case housing is also calculated in order to verify its structural strength and vibration performance. The analysis results show that the structural strength and modal frequency of the optimized transmission are higher than the design index,the optimization design of the complicated transmission case housing structure is realized.

In the multi-axis super-heavy-duty test platform,the high-power transfer case has the problem of broken teeth during fatigue endurance. The comprehensive analysis is carried out on the failure gears,the causes of gear damage,such as gear strength,shaft and box stiffness,gear tooth profile and tooth orientation precision,surface heat treatment,etc. are analyzed one by one,and finally it is positioned as the gear tooth surface grinding burns,resulting in reduced hardness of the tooth surface,contact fatigue strength decreased,the occurrence of premature failure damage. In the improvement work,the grinding process of the gear tooth surface is modified,and 100% grinding burn monitoring is added. The improved high-power transfer case passed the fatigue endurance test.

The wheel gearbox is a key component of Multi-axis super-heavy hybrid test platform,for the special nature of the application,on the one hand to meet the requirements of vehicle wheel power transmission requirements,while also meet lightweight and high reliability requirements.Therefore,in the wheel gearbox design,taking the lightweight for the wheel gearbox as the target,reliability as constraints,the optimization design scheme of the wheel gearbox is proposed.After the high- speed test,full load fatigue test and overload fatigue test verification,the wheel gearbox performance and reliability meet the requirements of super- heavy hybrid multi- axis test platform.

The topology optimization design of the complicated transfer case housing is conducted by using the variable density method. Taking the minimum compliance as the optimization objective and the volume fraction,static displacement,static stress,modal frequency and machining process as constrains condition,the topology optimization analysis of external shape and internal rib plate are carried out. Then,the static strength and modal character analysis of the optimized transfer case housing are carried out. The analysis results demonstrate that the static strength and modal frequency are higher than the design objective,the topology optimization design of complex housing structure is realized.

Accurate and reliable state of health (SOH) estimation is extremely crucial for the safe and stable operation of lithium-ion batteries (LIBs). In this paper, a method based on Lévy roulette- and fitness-distance balance-enhanced coyote optimization algorithm-optimized long short-term memory (LRFDBCOA-LSTM) is employed for SOH estimation of LIB. Firstly, six health features are extracted from battery charging and discharging data, and Savitzky–Golay is used to filter the feature data to improve correlation between feature and SOH. Then, Lévy roulette and fitness-distance balance (FDB) strategies are used to improve the coyote optimization algorithm (COA), i.e., LRFDBCOA. Meanwhile, the improved algorithm is used to optimize the internal parameters of long short-term memory (LSTM) neural network. Finally, the effectiveness of the proposed model is comprehensively validated using five evaluation indicators based on battery data obtained under three different testing conditions. The experimental results manifest that after algorithm improvement and network parameter optimization, the performance of the model is significantly improved. In addition, the method has high estimation accuracy, strong generalization, and strong robustness for SOH estimation with a maximum R2 of 0.9896 and minimum R2 of no less than 0.9711. [ABSTRACT FROM AUTHOR]

The transformation of taxation processes and the optimization and modeling of their management systems are hot topics in many disciplines such as public management and computer science. Therefore, the intelligent tax management is used to implement the tax process. Meanwhile, tax indicators are adopted as independent variables, and the Logistic regression model is applied to check the selected cases to determine corporate information, which further eliminates less relevant indicators based on the selection results to obtain a more accurate model. In addition, the system modularization design method is applied to design and plan the specific function process of system realization in detail, establishing the necessary business function which can be formed. Moreover, the test process is performed according to the simulation test of the function and the performance of the tax management module. It is proved that the application level of the design module in the paper can meet the current needs, and has the ability of intelligent data analysis and discrimination, which can be promoted within the scope of tax management. [ABSTRACT FROM AUTHOR]

In order to study the permeability evolution law of coal and rock under the action of mining dynamic load, the Darcy law steady-state measurement method was adopted to conduct the stress-strain permeability experiment of coal and rock using the triaxial compression permeability experiment device. The experimental results show that the increase of confining pressure prevents the development of tensile crack, resulting in the increase of stress peak and permeability decrease of the total stress-strain curve of coal and rock. With the same confining pressure, the variation trend of the coal rock strain-permeability curve and the stress-strain curve is basically the same, and there is a causal relationship, resulting in the hysteresis of the coal rock strain-permeability curve compared with the stress-strain curve.

The bacteriocin-producing Lactiplantibacillus plantarum SL47 was isolated from conventional fermented sausages, and the bacteriocin SL47 was purified using ethyl acetate, Sephadex G-25 gel chromatography, and reversed-phase high-performance liquid chromatography (RP-HPLC). Bacteriocin SL47 was identified by HPLC-MS/MS combined with whole-genome sequencing, and the results showed it consisted of plantaricin A, J, K, and N. Further characterization analysis showed that the bacteriocin SL47 was highly thermostable (30 min, 121 °C), pH stable (2-10), sensitive to protease and exhibited broad-spectrum antibacterial ability against Gram-positive and Gram-negative bacteria. The mechanism of action showed that the bacteriocin SL47 increased cell membrane permeability, and 2 × minimum inhibitory concentration (MIC) treatment for 40 min caused apoptosis of Staphylococcus aureus F2. The count of S. aureus in the sausage that was inoculated with L. plantarum SL47 and bacteriocin SL47 decreased by about 64% and 53% of that in the initial stage, respectively. These results indicated the potential of L. plantarum SL47 and bacteriocin SL47 as a bio-preservative in meat products., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

(2 S )-Naringenin is an important flavonoid precursor, with multiple nutritional and pharmacological activities. Both (2 S )-naringenin and other flavonoid production are hindered by poor water solubility and inhibited cell growth. To address this, we increased solubility and improved cell growth by partially glycosylating (2 S )-naringenin to naringenin-7-O-glucoside, which facilitated increased extracellular secretion, by knocking out endogenous glycosyl hydrolase genes, EXG1 and SPR1 , and expressing the glycosyltransferase gene ( UGT733C6 ). Naringenin-7-O-glucoside synthesis was further improved by optimizing UDP-glucose and shikimate pathways. Then, hydrochloric acid was used to hydrolyze naringenin-7-O-glucoside to (2 S )-naringenin outside the cell. Thus, our optimized Saccharomyces cerevisiae strain E32T19 produced 1184.1 mg/L (2 S )-naringenin, a 7.9-fold increase on the starting strain. Therefore. we propose that glycosylation modification is a useful strategy for the efficient heterologous biosynthesis of (2 S )-naringenin in S. cerevisiae .

8-prenylnaringenin (8-PN) is a potent estrogen with high medicinal values. It also serves as an important precursor for many prenylated flavonoids. Microbial synthesis of 8-PN is mainly hindered by the low catalytic activity of prenyltransferases (PTS) and insufficient supply of precursors. In this work, a SfN8DT-1 from Sophora flavescens was used to improve the efficiency of (2 S )-naringenin prenylation. The predicted structure of SfN8DT-1 showed that its main body is comprised of 9 α-helices and 8 loops, along with a long side chain formed by nearly 120 amino acids. SfN8DT-1 mutants with different side-chain truncated were tested in Saccharomyces cerevisiae . A mutant expressing the truncated enzyme at K62 site, designated as SfND8T-1-t62, produced the highest 8-PN titer. Molecular docking of SfN8DT-1-t62 with (2 S )-naringenin and dimethylallyl diphosphate (DMAPP) showed that K185 was a potentially crucial residue. Alanine scanning within a range of 0.5 nm around these two substrates showed that the mutant K185A may decrease its affinity to substrates, which also indicated K185 was a potentially critical residue. Besides, the mutant K185W enhanced the affinity to ligands implied by the simulated saturation mutation, while the saturated mutation of K185 showed a great decrease in 8-PN production, indicating K185 is vital for the activity of SfN8DT-1. Subsequently, overexpressing the key genes of Mevalonate (MVA) pathway further improved the titer of 8-PN to 31.31 mg/L, which indicated that DMAPP supply is also a limiting factor for 8-PN synthesis. Finally, 44.92 mg/L of 8-PN was produced in a 5 L bioreactor after 120 h, which is the highest 8-PN titer reported to date.

Flavan-3-ols are a group of flavonoids that exert beneficial effects. This study aimed to enhance key metabolic processes related to flavan-3-ols biosynthesis. The engineered Saccharomyces cerevisiae strain E32 that produces naringenin from glucose was further engineered for de novo production of two basic flavan-3-ols, afzelechin (AFZ) and catechin (CAT). Through introduction of flavonoid 3-hydroxylase, flavonoid 3'-hydroxylase, dihydroflavonol 4-reductase (DFR), and leucoanthocyanidin reductase (LAR), de novo production of AFZ and CAT can be achieved. The combination of Fa DFR from Fragaria × ananassa and Vv LAR from Vitis vinifera was optimal. (GGGGS) 2 and (EAAAK) 2 linkers between DFR and LAR proved optimal for the production of AFZ and CAT, respectively. Optimization of promoters and the enhanced supply of NADPH further increased the production. By combining the best engineering strategies, the optimum strains produced 500.5 mg/L AFZ and 321.3 mg/L CAT, respectively, after fermentation for 90 h in a 5 L bioreactor. The strategies presented could be applied for a more efficient production of flavan-3-ols by various microorganisms.

Saccharomyces cerevisiae is one of the most important hosts in metabolic engineering. Advanced gene editing technology has been widely used in the design and construction of S. cerevisiae cell factories. With the rapid development of gene editing technology, early gene editing technologies based on recombinase and homologous recombination have been gradually replaced by new editing systems. In this review, the principle and application of gene editing technology in S. cerevisiae are summarized. Here, we first briefly describe the classical gene editing techniques of S. cerevisiae. Then elaborate the genome editing system of MegNs, ZFNs and TALENs based on endonuclease. The latest research progress is especially introduced and discussed, including the CRISPR/Cas system, multi-copy integration of heterologous metabolic pathways, and genome-scale gene editing. Finally, we envisage the application prospects and development directions of Saccharomyces cerevisiae gene editing technology.

BACKGROUND miR-181a is a small non-coding RNA known to be dysregulated in osteoarthritis (OA), but the role of miR-181a in human OA remains unclear. The aim of this study was to identify its function and molecular target in chondrocytes during OA pathogenesis. MATERIAL AND METHODS The function of miR-181a was assessed by gain-of-function studies in human OA chondrocytes. Potential targets of miR-181a were predicted using series of bioinformatics and intersection analysis, then confirmed by luciferase reporter assay. Gene expression was quantified using quantitative reverse transcription PCR (qRT-PCR) assays, and protein production was quantified by Western blot analysis. RESULTS The FITC apoptosis assay results indicated that the upregulation of miR-181a led to an increase of apoptosis rate in chondrocytes. Then bioinformatic analysis identified potential target sites of the miR-181a located in the 3' untranslated region of GPD1L. Dual-luciferase reporter assays results showed that GPD1L is a target gene of miR-181a. Furthermore, Western blot and qRT-PCR analysis demonstrated that miR-181a inhibited GPD1L gene expression. Increased GPD1L and decreased miRNA-181a were observed in tissues from osteoarthritis patients. Moreover, we found a highly negative correlation between miRNA-181a and GPD1L. CONCLUSIONS Our results demonstrated that miR-181a may play an important role in the pathogenesis of OA through targeting GPD1L and regulating chondrocyte apoptosis.