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Tracking headway time is an important target the Metro capacity. In order to meet the 150 second design capacity in the Shanghai Chongming Line long tunnel section, this article firstly analyzes the train tracking headway time under different ventilation shaft control modes. Then, it develops a simulation tool for optimizing the location of ventilation shafts in long tunnel sections. And it develops different tracking control model algorithms for train in the ventilation shaft sections. Finally, it takes the long tunnel section between Changxingdao Station and Chenjiazhen Station in the Shanghai Chongming Line as an example to demonstrate the usability of this simulation system and the reference value of simulation results.

Exhausted CD8 + T cells are key targets of immune checkpoint blockade therapy and their ineffective reinvigoration limits the durable benefit in some cancer patients. Here, we demonstrate that histone demethylase LSD1 acts to enforce an epigenetic program in progenitor exhausted CD8 + T cells to antagonize the TCF1-mediated progenitor maintenance and to promote terminal differentiation. Consequently, genetic perturbation or small molecules targeting LSD1 increases the persistence of the progenitor exhausted CD8 + T cells, which provide a sustained source for the proliferative conversion to numerically larger terminally exhausted T cells with tumor-killing cytotoxicity, thereby leading to effective and durable responses to anti-PD1 therapy. Collectively, our findings provide important insights into epigenetic mechanisms that regulate T cell exhaustion and have important implications for durable immunotherapy. Dynamic changes in chromatin landscape affect CD8 + T cell phenotype and function in chronic infections and cancer. Here the authors show that targeting the histone demethylase LSD1 increases the persistence of progenitor exhausted CD8 + T cells, improving response to immune checkpoint blockade in preclinical cancer models.

The adult brain contains dozens of different types of interneurons that control and refine neuronal circuits. Mi et al. used single-cell transcriptomics to investigate when these subtypes emerge during interneuron development in the mouse. Transcriptomes of embryonic interneurons showed similarities to adult classes of differentiated interneurons, thus dividing the immature embryonic interneurons themselves into classes. Nearly a dozen classes of embryonic neurons could be identified soon after their last mitosis by transcriptomic similarity with known classes of adult cortical interneurons. Thus, the fate of embryonic interneurons can be read in their transcriptomes well before the neurons migrate and reach their final sites of differentiation and circuit integration. Science , this issue p. 81 Single-cell transcriptomics reveals embryonic correlates of adult interneuron classes. GABAergic interneurons (GABA, γ-aminobutyric acid) regulate neural-circuit activity in the mammalian cerebral cortex. These cortical interneurons are structurally and functionally diverse. Here, we use single-cell transcriptomics to study the origins of this diversity in the mouse. We identify distinct types of progenitor cells and newborn neurons in the ganglionic eminences, the embryonic proliferative regions that give rise to cortical interneurons. These embryonic precursors show temporally and spatially restricted transcriptional patterns that lead to different classes of interneurons in the adult cerebral cortex. Our findings suggest that shortly after the interneurons become postmitotic, their diversity is already patent in their diverse transcriptional programs, which subsequently guide further differentiation in the developing cortex.

Aiming at the problem of indoor environment, signal non-line-of-sight propagation and other factors affect the accuracy of indoor locating, an algorithm of indoor fingerprint localization based on the eight-neighborhood template is proposed. Based on the analysis of the signal strength of adjacent reference points in the fingerprint database, the methods for the eight-neighborhood template matching and generation were studied. In this study, the indoor environment was divided into four quadrants for each access point and the expected values of the received signal strength indication (RSSI) difference between the center points and their eight-neighborhoods in different quadrants were chosen as the generation parameters. Then different templates were generated for different access points, and the unknown point was located by the Euclidean distance for the correlation of RSSI between each template and its coverage area in the fingerprint database. With the spatial correlation of fingerprint data taken into account, the influence of abnormal fingerprint on locating accuracy is reduced. The experimental results show that the locating error is 1.0 m, which is about 0.2 m less than both K-nearest neighbor (KNN) and weighted K-nearest neighbor (WKNN) algorithms.

The mechanisms of soil preferential flow occurrence and development are influenced by topographic and geomorphological factors. However, the complex distribution patterns of soil preferential flow paths on different slopes remain unclear. Therefore, taking the subtropical evergreen broad-leaved forest area of Simian Mountain as the study area, this study conducted a quantitative analysis of the spatial distribution characteristics and spatial association of soil preferential flow at different slope positions (slope shoulder (SS), mid-slope (SM) and slope foot (SF)) using field staining tracer tests and spatial point pattern analysis. Results showed that the maximum infiltration depth, the depth of matrix flow, average dye coverage, preferential flow fraction and length index of the SM plot were all greater than those of the SS and SF plots. The number of preferential flow paths in different slope positions decreases with soil depth, with most preferential flow paths measuring 2.5–5.0 mm in each soil layer. The total number of preferential flow paths in SM plot was approximately twice that of the SS and SF plots, and the preferential flow paths in SM plot, regardless of pore size, were all in an aggregated distribution. These findings indicated that differences in soil physical properties and vegetation coverage at different slope positions lead to variations in the spatial distribution and association of soil preferential flow paths. Accordingly, strategies must be modified for the distribution, storage and utilisation of soil water resources. This study provides a theoretical basis for the effective management and protection of water resources in the Simian Mountain area and a scientific basis for exploring the mechanisms of the occurrence and development of the water cycle in forested watersheds.

Background The Interleukin-6 (IL-6)-signal transducer and activator of transcription 3 (STAT3) pathway, along with the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway, are critical contributors to neuroinflammation in Alzheimer’s disease (AD). Although previous research outside the context of AD has indicated that the IL-6-STAT3 pathway may regulate the cGAS-STING pathway, the exact molecular mechanisms through which IL-6-STAT3 influences cGAS-STING in AD are still not well understood. Methods The activation of the IL-6-STAT3 and cGAS-STING pathways in the hippocampus of 5×FAD and WT mice was analyzed using WB and qRT-PCR. To explore the effects of IL-6 deficiency, Il6 +/− mice were crossed with 5×FAD mice, and the subsequent impact on hippocampal STAT3 pathway activity, cGAS-STING pathway activation, amyloid pathology, neuroinflammation, and cognitive function was evaluated through WB, qRT-PCR, immunohistochemistry, ThS staining, ELISA, and behavioral tests. The regulatory role of STAT3 in the transcription of the Cgas and Sting genes was further validated using ChIP-seq and ChIP-qPCR on hippocampal tissue from 5×FAD and Il6 −/− : 5×FAD mice. Additionally, in the BV2 microglial cell line, the impact of STAT3 activation on the transcriptional regulation of Cgas and Sting genes, as well as the production of inflammatory mediators, was examined through WB and qRT-PCR. Results We observed marked activation of the IL-6-STAT3 and cGAS-STING pathways in the hippocampus of AD mice, which was attenuated in the absence of IL-6. IL-6 deficiency reduced beta-amyloid deposition and neuroinflammation in the hippocampus of AD mice, contributing to cognitive improvements. Further analysis revealed that STAT3 directly regulates the transcription of both the Cgas and Sting genes. These findings suggest a potential mechanism involving the STAT3-cGAS-STING pathway, wherein IL-6 deficiency mitigates neuroinflammation in AD mice by modulating this pathway. Conclusion These findings indicate that the STAT3-cGAS-STING pathway is critical in mediating neuroinflammation associated with AD and may represent a potential therapeutic target for modulating this inflammatory process in AD.

Taking the cantilever rotor of a turbine engine as the research object, a dynamic and finite-element model of the cantilever rotor is established, and the effectiveness of the model is verified by the rotor test platform. The transfer function method is used to balance the rotor system under unbalanced excitation, and the experiments prove that the method adopted in this paper has a good balancing effect and effectively reduces the vibration of the unbalanced rotor. On this basis, the experimental tests and simulation analyses of the rotor vibration response under different unbalanced phases and difference combinations are carried out, and the influence of the unbalanced phase’s difference combinations on unbalance and dynamic balance is analyzed. The results show that the vibration response of the system decreases with the increase in the unbalanced phase difference combinations, and the amplitude of the vibration induced by the unbalance of the reverse combination is smaller than that of the in-phase combination. The work in this paper can provide a theoretical basis for the dynamic balance and vibration control of the flexible rotor of an aero-engine.

Human nervous system development is an intricate and protracted process that requires precise spatiotemporal transcriptional regulation. We generated tissue-level and single-cell transcriptomic data from up to 16 brain regions covering prenatal and postnatal rhesus macaque development. Integrative analysis with complementary human data revealed that global intraspecies (ontogenetic) and interspecies (phylogenetic) regional transcriptomic differences exhibit concerted cup-shaped patterns, with a late fetal-to-infancy (perinatal) convergence. Prenatal neocortical transcriptomic patterns revealed transient topographic gradients, whereas postnatal patterns largely reflected functional hierarchy. Genes exhibiting heterotopic and heterochronic divergence included those transiently enriched in the prenatal prefrontal cortex or linked to autism spectrum disorder and schizophrenia. Our findings shed light on transcriptomic programs underlying the evolution of human brain development and the pathogenesis of neuropsychiatric disorders.

Background Elymus sibiricus L. is a native grass species vital for ecological restoration and livestock production on China’s Qinghai-Tibet Plateau, valued for its high yield, superior quality, and strong adaptability. Its awns, a significant morphological structure of the seed, significantly influence seed yield and stress resistance. This study utilized 14 E. sibiricus accessions with distinct awn lengths to investigate the influence of awn length on seed yield and drought resistance. Additionally, it aims to elucidate the molecular mechanisms underlying awn length regulation in E. sibiricus . Results Analysis of five agronomic traits related to seed yield revealed a significant positive correlation between awn length and thousand-grain weight. Principal component analysis and cluster analysis classified the 14 accessions into the long-awned and short-awned groups, with the long-awned group exhibiting higher seed yield potential. Anatomical analysis of awn tissues of the QH002 and GS002 accessions during four stages—heading, flowering, filling, and milk ripening—revealed that the long-awn genotype possessed more developed structures including parenchyma cells, sclerenchyma cells, vascular bundles, and stomata. These structures endows it with enhanced conduction, support, and defense functions. Transcriptome analysis of middle spikes from the QH002 and GS002 genotypes revealed 6,321 differentially expressed genes (DEGs), primarily enriched in metabolic pathways such as photosynthesis, galactose metabolism, and tyrosine metabolism. Among them, two photosystem II-related genes ( EsiS02g0031800 , EsiH02g0028770 ) and 11 DEGs associated with carbohydrate metabolism were identified as key candidate genes. Under terminal drought stress, the long-awned accession (QH002) exhibited higher relative water and proline content, and increased antioxidant enzyme activities, compared to the short-awned accession (GS002), whereas malondialdehyde content was higher in the latter. These results indicate that the long-awned accessions possesses enhanced drought tolerance compared to the short-awned accessions. Conclusions This study demonstrated that long-awned E. sibiricus exhibits higher seed production potential and stronger drought resistance, providing new insights and theoretical support for the breeding of high-yielding and stress-tolerant E. sibiricus varieties. It further adds to our understanding of the molecular mechanisms governing awn morphogenesis and length determination.

The production of light olefins from polyethylene (PE) has significant industrial potential. Zeolites have been widely used in petroleum refining for their ability to cleave C–C/C–H bonds and facilitate light olefins selectivity, thanks to their adjustable acidity and pore structure. However, the interaction between zeolites and conventional hydrocarbons or polymer reactants is quite different, a distinction frequently overlooked but has great influence on their reaction. Based on this, we describe a PE self-confined cracking mechanism that can produce C 3 -C 8 olefins with exceptional yields, surpassing 70% under mild conditions (300 °C). Interestingly, the product distribution is only dependent on the degree of self-confinement and melt mass-flow rate (MFR) of PE, regardless of the porous structure, metal content, and internal acid properties of zeolite. Most importantly, this process allows for flexible tandem catalytic reforming to yield more than 67% C 2 –C 4 light olefins and 23% separable BTX, demonstrating great potential to promote chemical recycling of waste polyolefin plastics. Producing light olefins from polyethylene (PE) is challenging. This study reveals a PE self-confined cracking mechanism over zeolites, achieving exceptional olefin yields (>70%) independent of zeolite properties, enabling efficient plastic recycling.