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Tire cavity noise is becoming more prominent as the speed of electric vehicles is getting higher. This study aims to use a built-in sound-absorbing material to reduce tire cavity noise. First, the radial force was extracted by rolling analysis, and the tire cavity noise was obtained. Then, in order to investigate how the placement of sound-absorbing material affects the noise reduction, sound-absorbing material was applied to the inner side of tire’s side and tread position respectively. Finally, studies were done on the impact of sound-absorbing material’s density, flow resistance, porosity, and thickness on tire noise reduction. The best way to reduce noise with a 215/55R17 tire was to apply sound-absorbing material at side position. The density, porosity, flow resistance and thickness of the sound-absorbing material were 55 kg/m3, 0.95, 5000 Pa·s/m2 and 40 mm, respectively. The A-weighted sound pressure level decreased by 27.7 dB compared with that before the built-in sound-absorbing material. In response to the uncertainties on the reduction achieved by the sound-absorbing material, this study offers some recommendations for noise reduction of tire cavity. The studied effect is limited to the tire cavity, and the effect on the emitted sound energy has not been evaluated.

Heterogeneity of endothelial cell (EC) populations reflects their diverse functions in maintaining tissue's homeostasis. However, their phenotypic, molecular, and functional properties are not entirely mapped. We use the Tie2-CreERT2;Rosa26-tdTomato reporter mouse to trace, profile, and cultivate primary ECs from different organs. As paradigm platform, we use this strategy to study bone marrow endothelial cells (BMECs). Single-cell mRNA sequencing of primary BMECs reveals that their diversity and native molecular signatures is transitorily preserved in an ex vivo culture that conserves key cell-to-cell microenvironment interactions. Macrophages sustain BMEC cellular diversity and expansion and preserve sinusoidal-like BMECs ex vivo. Endomucin expression discriminates BMECs in populations exhibiting mutually exclusive properties and distinct sinusoidal/arterial and tip/stalk signatures. In contrast to arterial-like, sinusoidal-like BMECs are short-lived, form 2D-networks, contribute to in vivo angiogenesis, and support hematopoietic stem/progenitor cells in vitro. This platform can be extended to other organs' ECs to decode mechanistic information and explore therapeutics.

BackgroundDuring acute myeloid leukemia (AML) growth, the bone marrow (BM) niche acquires significant vascular changes that can be offset by therapeutic blast cytoreduction. The molecular mechanisms of this vascular plasticity remain to be fully elucidated. Herein, we report on the changes that occur in the vascular compartment of the FLT3-ITD+ AML BM niche pre and post treatment and their impact on leukemic stem cells (LSCs).MethodsBM vasculature was evaluated in FLT3-ITD+ AML models (MllPTD/WT/Flt3ITD/ITD mouse and patient-derived xenograft) by 3D confocal imaging of long bones, calvarium vascular permeability assays, and flow cytometry analysis. Cytokine levels were measured by Luminex assay and miR-126 levels evaluated by Q-RT-PCR and miRNA staining. Wild-type (wt) and MllPTD/WT/Flt3ITD/ITD mice with endothelial cell (EC) miR-126 knockout or overexpression served as controls. The impact of treatment-induced BM vascular changes on LSC activity was evaluated by secondary transplantation of BM cells after administration of tyrosine kinase inhibitors (TKIs) to MllPTD/WT/Flt3ITD/ITD mice with/without either EC miR-126 KO or co-treatment with tumor necrosis factor alpha (TNFα) or anti-miR-126 miRisten.ResultsIn the normal BM niche, CD31+Sca-1high ECs lining arterioles have miR-126 levels higher than CD31+Sca-1low ECs lining sinusoids. We noted that during FLT3-ITD+ AML growth, the BM niche lost arterioles and gained sinusoids. These changes were mediated by TNFα, a cytokine produced by AML blasts, which induced EC miR-126 downregulation and caused depletion of CD31+Sca-1high ECs and gain in CD31+Sca-1low ECs. Loss of miR-126high ECs led to a decreased EC miR-126 supply to LSCs, which then entered the cell cycle and promoted leukemia growth. Accordingly, antileukemic treatment with TKI decreased the BM blast-produced TNFα and increased miR-126high ECs and the EC miR-126 supply to LSCs. High miR-126 levels safeguarded LSCs, as shown by more severe disease in secondary transplanted mice. Conversely, EC miR-126 deprivation via genetic or pharmacological EC miR-126 knock-down prevented treatment-induced BM miR-126high EC expansion and in turn LSC protection.ConclusionsTreatment-induced CD31+Sca-1high EC re-vascularization of the leukemic BM niche may represent a LSC extrinsic mechanism of treatment resistance that can be overcome with therapeutic EC miR-126 deprivation.

Red tourism is a distinctive form of tourism in China. Its network attention serves as a typical indicator to measure the level of promotion and publicity for red tourism, as well as an important reflection of its influence. Understanding the network structure of red tourism is of significant importance for optimizing the spatial pattern of tourism and promoting the development of the tourism industry. Based on this, this study takes the classic red tourism attractions in Shaanxi province, China as an example and constructs a multi-source data network attention evaluation index. Additionally, it employs social network theory to explore the network attention and tourist flow characteristics of the case study area. Research shows that: (1) Overall, the network attention to case-based destinations is relatively low, and there are significant differences in network attention among different attractions. Spatially, the distribution of network attention is uneven. This is manifested by higher network attention to attractions in Yan'an city and lower network attention to attractions in other regions. (2) There are differences in the network attention of different types of attractions. High-level attractions have a higher level of online attention, while low-level attractions have a lower level of network attention. Additionally, archaeological sites tend to receive a higher level of online attention. (3) The network density of tourist flow is low, and the tourism connections between nodes are not closely linked. The linkage between core nodes and edge nodes in tourism is poor. Developed tourism routes only exist in core nodes. (4) Nodes such as Zaoyuan revolution site, Yangjialing revolution site, and Wangjiaping revolution site have a significant influence in the network structure. In addition, the integration and development between red nodes and non-red nodes have been achieved. (5) There is a correlation between network attention and tourist flow, as well as a 'misplacement' feature. Based on the characteristics of attractions, they can be divided into four types: bright-star attractions, cash-cow attractions, thin-dog attractions, and question attractions. Based on the above conclusions, this study proposes targeted development recommendations.

Herpes simplex virus type 1 (HSV-1) is an ubiquitous pathogen that can infect humans through skin or mucous regions. This study was to explore the effects and underlying mechanism of HSV-1 as examined within the human epidermal melanocyte cell line, PIG1. Our results showed that following HSV-1 infection, PIG1 cells shrank and acquired a rounded shape, while the numbers and lengths of their dendrites decreased and melanogenesis was inhibited. Meanwhile, the HSV-1 receptors (nectin-1, herpes virus entry mediator, paired immunoglobulin-like type 2 receptor alpha) and phospho-extracellular signal-regulating kinase (p-ERK) were all substantially decreased, while vomeronasal type-1 receptor 5 (VN1R5) increased. Results of RNA interference and protein inhibitor assays revealed that knockdown of VN1R5 increased the expression of p-ERK and microphthalmia-associated transcription factor (MITF), while an inhibition of ERK decreased VN1R5 expression. Taken together, our study provides the first evidence that HSV-1 can infect human normal melanocytes and inhibit melanogenesis through VN1R5/ERK pathway. [ABSTRACT FROM AUTHOR]

Continuous recombination and variation during replication could lead to rapid evolution and genetic diversity of HIV-1. Some studies had identified that it was easy to develop new recombinant strains of HIV-1 among the populations of men who have sex with men (MSM). Surveillance of genetic variants of HIV-1 in key populations was crucial for comprehending the development of regional HIV-1 epidemics. The finding was reported the identification of two new unique recombinant forms (URF 20110561 and 21110743) from individuals infected with HIV-1 in Tongzhou, Beijing in 2020–2022. Sequences of near full-length genome (NFLG) were amplified, then identification of amplification products used phylogenetic analyses. The result showed that CRF01_AE was the main backbone of 20110561 and 21110743. In the gag region of the virus, 20110561 was inserted two fragments from CRF07_BC, while in the pol and tat regions of the virus, 21110743 was inserted four fragments from CRF07_BC. The CRF01_AE parental origin in the genomes of the two URFs was derived from the CRF01_AE Cluster 4. In the phylogenetic tree, the CRF07_BC parental origin of 20110561 clustered with 07BC_N and the CRF07_BC parental origin of 21110743 clustered with 07BC_O. In summary, the prevalence of novel second-generation URFs of HIV-1 was monitored in Tongzhou, Beijing. The emergence of the novel CRF01_AE/CRF07_BC recombination demonstrated that there was a great significance of continuous monitoring of new URFs in MSM populations to prevent and control the spreading of new HIV-1 URFs. [ABSTRACT FROM AUTHOR]