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The diesel engine combustion process is mainly controlled by the fuel injection characteristics, which will have a direct impact on the performance of the diesel engine, more flexible injection strategy is the development direction of high pressure common-rail system. In order to obtain the change law of the performance of extra-high pressure common-rail diesel engine under variable injection strategy, and improve the overall performance of diesel engine, the effect of different post-injection parameters on the performance of diesel engine was studied on a self-designed extra-high pressure common-rail diesel engine experiment bench, and the relevant results were discussed and analyzed. The results show that: with the rise of post-injection fuel quantity, NOx concentration and soot concentration decrease gradually, and with the rise of post-injection interval angle, NOx concentration decreases gradually, while soot concentration first decreases and then increases. Therefore, choosing post-injection fuel quantity and post-injection interval angle rationally can achieve lower NOx and soot emission at the same time. Meanwhile, with the rise of post-injection fuel quantity or post-injection interval angle, the fuel consumption rate presents an increasing trend.

Efficient occlusion of particulate additives into a single crystal has garnered an ever‐increasing attention in materials science because it offers a counter‐intuitive yet powerful platform to make crystalline nanocomposite materials with emerging properties. However, precisely controlling the spatial distribution of the guest additives within a host crystal remains highly challenging. We herein demonstrate a unique, straightforward method to engineer the spatial distribution of copolymer nanoparticles within calcite (CaCO3) single crystals by judiciously adjusting initial [Ca2+] concentration used for the calcite precipitation. More specifically, polymerization‐induced self‐assembly is employed to synthesize well‐defined and highly anionic poly(3‐sulfopropyl methacrylate potassium)41‐block‐poly(benzyl methacrylate)500 [PSPMA41‐PBzMA500] diblock copolymer nanoparticles, which are subsequently used as model additives during the growth of calcite crystals. Impressively, such guest nanoparticles are preferentially occluded into specific regions of calcite depending on the initial [Ca2+] concentration. These unprecedented phenomena are most probably caused by dynamic change in electrostatic interaction between Ca2+ ions and PSPMA41 chains based on systematic investigations. This study not only showcases a significant advancement in controlling the spatial distribution of guest nanoparticles within host crystals, enabling the internal structure of composite crystals to be rationally tailored via a spatioselective occlusion strategy, but also provides new insights into biomineralization. [ABSTRACT FROM AUTHOR]

Although strategies of olefin hydroalkylation continue to emerge rapidly, the precise control of the regio- or chemoselectivity and the expansion of the reaction range are still challenges. Herein, a straightforward route for cobalt-catalyzed anti-Markovnikov hydroalkylation of unactivated olefins with alkyl iodides has been achieved. The developed reaction is compatible with oxa-, aza-, cyclo- and a series of other functional groups as well as the frameworks of some bioactive compounds. Mechanism studies confirm that an alkyl radical is involved and cobalt–alkyl insertion followed by protonation with water are possible pathways in this reaction. [ABSTRACT FROM AUTHOR]

Constructing accurate spatiotemporal correlations is a challenging task in joint prediction of multiple photovoltaic sites. Some advanced algorithms for incorporating other surrounding site information have been proposed, such as graph neural network-based methods, which are usually based on static or dynamic graphs to build spatial dependencies between sites. However, the possibility of the simultaneous existence of multiple spatial dependencies is not considered. This paper establishes a spatiotemporal prediction model based on hybrid spatiotemporal graph neural network. In this model, we apply adaptive hybrid graph learning to learn composite spatial correlations among multiple sites. A temporal convolution module with multi-subsequence temporal data input is used to extract local semantic information to better predict future nonlinear temporal dependencies. A spatiotemporal adaptive fusion module is added to address the issue of integrating diverse spatiotemporal trends among multiple sites. To assess the model's predictive performance, nine solar radiation observation stations were selected in two different climatic environments. The average root mean square error (RMSE) of the constructed model was 38.51 and 49.90 W/m2, with average mean absolute error (MAE) of 14.72 and 23.06 W/m2, respectively. Single-site and multi-site prediction models were selected as baseline models. Compared with the baseline models, the RMSE and MAE reduce by 3.1%–20.8% and 8.9%–32.8%, respectively, across all sites. The proposed model demonstrates the effectiveness of improving accuracy in forecasting solar irradiance through multi-site predictions. [ABSTRACT FROM AUTHOR]

The motion of a single active particle in one dimension with quenched disorder under the external force is investigated. Within the tailored parameter range, anomalous diffusion that displays weak ergodicity breaking is observed, i.e., non-ergodic subdiffusion and non-ergodic superdiffusion. This non-ergodic anomalous diffusion is analyzed through the time-dependent probability distributions of the particle's velocities and positions. Its origin is attributed to the relative weights of the locked state (predominant in the subdiffusion state) and running state (predominant in the superdiffusion state). These results may contribute to understanding the dynamical behavior of self-propelled particles in nature and the extraordinary response of nonlinear dynamics to the externally biased force. [ABSTRACT FROM AUTHOR]

Both glucose-regulated protein 78 kDa (GRP78) and glucose-regulated protein 94 kDa (GRP94) are important molecular chaperones that play critical roles in maintaining tumor survival and progression. This study investigated the effects in prostate cancer cells following the downregulation of GRP78 and GRP94.

Little is known about the influence of metabolic syndrome (MetS) on coronary artery calcification (CAC) in China. In this article, we aimed to explore the distribution of CAC in populations with and without MetS, and estimate the influence of MetS and its components on CAC in a community-based population of Beijing.A total of 1647 local residents of Beijing, age 40-77 years, were recruited for a cardiovascular risk factors survey and were determined fasting plasma glucose (FPG), blood lipids, and 64 multi-detector computed tomography (64-MDCT) coronary artery calcium score (CACS) measurement (Agatston scoring). The distribution of CAC was described, and the influence of MetS components on CAC was evaluated.In this population, the prevalence and extent of CAC increased with increasing age and both were higher in MetS subjects compared to nonMetS subjects (all P < 0.05), with the exception of those older than 65 years old. The risk of CAC increased with increasing numbers of MetS components, and the odds ratios for predicting positive CAC in subjects with 1, 2, 3, and = 4 MetS components were 1.60, 1.84, 2.12, and 3.12, respectively (all P < 0.05). Elevated blood pressure, elevated FPG, elevated triglycerides, and overweight increased the risk of CAC, yielding odds ratios of 2.64, 1.67, 1.32, and 1.37, respectively (all P < 0.05).In the Beijing community-based population, MetS increases the risk of CAC. The risk of CAC increases with increasing numbers of MetS components. Not only the number, but also the variety of risk factors for MetS is correlated with the risk of CAC. Elevated blood pressure, hyperglycemia, hypertriglyceridemia and overweight increase the risk of CAC.

2‐Acylindoles possess widespread applications in functional chemicals. However, the convenient and selective synthesis of such important substructures has to date remained a challenge. Herein, a method to achieve 2‐acylindoles from sulfoxonium ylides with o‐aminoaryl aldehydes catalysed by Iridium has been developed with the merits of broad substrate scope, good functional tolerance, high efficiency and operational simplicity, which provides an alternative way to access functionalized indoles. [ABSTRACT FROM AUTHOR]

Photoredox alkene or alkyne alkylsulfonylation has been achieved with phthalimide esters and sulfinates providing unexpected α-sulfones. Mechanistic studies disclose that the preferential alkyl radical addition to the alkene or the Markovnikov hydrosulfonation of the alkyne should contribute to the formation of the β-alkylated α-sulfones. Moreover, the reaction is easy to operate covering quite large substrate scales including primary, secondary and tertiary alkyl groups and all sorts of terminal aryl alkenes or alkynes. Besides, the reaction was also suitable for the sulfonylation of several drug molecules. [ABSTRACT FROM AUTHOR]

Diacylglycerol acyltransferase (DGAT) is a vital and sole rate-limiting enzyme involved in triacylglycerol synthesis. Identifying DGAT genes in Lindera glauca is essential for studying lipid metabolism pathways and developing novel oil crops with enhanced value. In the study reported in this paper, 15 LgDGAT family genes were first obtained from the L. glauca genome via bioinformatics analysis. We comprehensively analyzed their chromosome distribution, gene structure, subcellular localization, promoter prediction, phylogenetic relationships, tissue-specific expression, and expression patterns during different stages of fruit development. Our findings revealed that LgDGATs can be classified into DGAT1, DGAT2, DGAT3, and WSD (wax ester synthase/acyl-CoA: diacylglycerol acyltransferase) subfamilies distributed across chromosome 3, 5, 6, 8 and 11. LgDGATs' promoter region showed abundant elements linked to the light response and plant hormone response. Forms of LgDGAT1, LgDGAT2, and LgDGAT3 were primarily expressed in the early and late phases of fruit development, indicating their potential function in the growth and development of L. glauca, particularly in oil accumulation. Conversely, LgWSDs exhibited predominant expression in stems and leaves. This paper elucidates the gene structure and expression patterns of LgDGATs, providing a theoretical foundation for understanding the functionality of DGAT genes in Lindera species. [ABSTRACT FROM AUTHOR]

Sugarcane yellow leaf virus (SCYLV), a member of the genus Polerovirus in the family Luteoviridae, causes severe damage and represents a great threat to sugarcane cultivation and sugar industry development. In this study, inoculation of Nicotiana benthamiana plants with a potato virus X (PVX)-based vector carrying the SCYLV P0 gene induced typical mosaic, leaf rolling symptoms and was associated with a hypersensitive-like response (HLR) necrosis symptom, which is accompanied with a systemic burst of H2O2 and also leads to higher PVX viral genome accumulation levels. Our results demonstrate that SCYLV P0 is a pathogenicity determinant and plays important roles in disease development. To further explore its function in pathogenic processes, a yeast two-hybrid assay was performed to screen the putative P0-interacting host factors. The recombinant plasmid pGBKT7-P0 was constructed as a bait and transformed into the yeast strain Y2HGold. The ROC22 cultivar (an important parental resource of the main cultivar in China) cDNA prey library was constructed and screened by co-transformation with the P0 bait. We identified 28 potential interacting partners including those involved in the optical signal path, plant growth and development, transcriptional regulation, host defense response, and viral replication. To our knowledge, this is the first time we have reported the host proteins interacting with the P0 virulence factor encoded by sugarcane yellow leaf virus. This study not only provides valuable insights into elucidating the molecular mechanism of the pathogenicity of SCYLV, but also sheds light on revealing the probable new pathogenesis of Polerovirus in the future. [ABSTRACT FROM AUTHOR]

The persistent heavy precipitation during summer in 1998 and 2020 in the middle and lower reaches of the Yangtze River basin (MLYRB) caused the most influential floods in the region during recent 30 years. Previous studies paid lots of attention to those events by analysing the spatial–temporal distributions and the circulation backgrounds; however, the comparison of moisture contribution to summer precipitation in the MLYRB in 1998 and 2020 have rarely been well addressed. This study tracked the moisture sources of summer precipitation in 1998 and 2020 in the MLYRB based on an Eulerian moisture tracking model (WAM‐2layers) forced with ERA5 dataset and explored the similarities and differences of moisture transport and moisture contribution during the two periods. Results showed that the moisture contribution to summer precipitation in the MLYRB mainly transported by the southwest monsoon system, with the major sources extended across the Indo‐China Peninsula, the Bay of Bengal and the Arabian Sea, to the south Indian Ocean. During the summer of 1998 and 2020, increased moisture contributions were mainly from the southwestern sources, particularly the Indo‐China Peninsula and its surroundings. Meanwhile, decreased moisture contributions were found from the local recycling and the northeastern sources. In comparison with summer 1998, there were less moisture can be transported from the low‐latitude oceans (particularly the Arabian Sea and the Bay of Bengal) to the MLYRB during summer 2020, except for the Northwestern Pacific. [ABSTRACT FROM AUTHOR]