Population Exposure Changes to One Heat Wave and the Influencing Factors Using Mobile Phone Data—A Case Study of Zhuhai City, China

The frequent occurrence of extreme high temperature weather and heat waves has greatly affected human life. This paper analyzes population exposure and its influencing factors during a heat wave incident in Zhuhai from 6 to 12 September 2021 based on real-time mobile phone data and meteorological data. The results show that the most areas of Zhuhai are affected by high temperature during this heat wave incident. The hourly population exposure is directly proportional to hourly heat wave coverage. In terms of time dimension, the overall population exposure shows a trend of decreasing and then increasing. In terms of spatial dimensions, high population exposure is concentrated in areas such as primary and secondary schools, colleges and universities, office buildings, and residential areas. Low exposure is distributed in most of the mountainous areas along the southern coast. In addition, the leading factors that cause changes in population exposure in different periods of the heat wave cycle are different, which rely more on either climatic factors or population factors

An Improved Multi-Mode Two-Step Floating Catchment Area Method for Measuring Accessibility of Urban Park in Tianjin, China

Parks, as a major infrastructure that provide public service for urban residents, play a vital role in promoting urban livability and public health. Under the framework of spatial equity, more sophisticated accessibility methods were used on measuring urban park accessibility such as multi-mode 2SFCA. However, the accessibility of residential areas near parks was seriously underestimated by using the multi-mode 2SFCA method. Thus, this study aimed to propose an improved multi-mode 2SFCA method to measure urban park accessibility with a more appropriate approach, by taking residential areas of Tianjin central city as the spatial unit. The results indicate that all residential areas can obtain urban park accessibility, but the spatial distribution of urban park accessibility is heterogeneous. The numerical value of urban park accessibility decreases as the travel time from residential areas to urban parks increases; it is shown that the proposed method can provide a more realistic evaluation compared to the traditional multi-mode 2SFCA method. This study provides a comprehensive and realistic insight into acquainting with urban park accessibility and helps urban planners formulate effective policies and strategies to ease spatial imbalance

Diverse Roles of the Exon Junction Complex Factors in the Cell Cycle, Cancer, and Neurodevelopmental Disorders-Potential for Therapeutic Targeting

The exon junction complex (EJC) plays a crucial role in regulating gene expression at the levels of alternative splicing, translation, mRNA localization, and nonsense-mediated decay (NMD). The EJC is comprised of three core proteins: RNA-binding motif 8A (RBM8A), Mago homolog (MAGOH), eukaryotic initiation factor 4A3 (eIF4A3), and a peripheral EJC factor, metastatic lymph node 51 (MLN51), in addition to other peripheral factors whose structural integration is activity-dependent. The physiological and mechanistic roles of the EJC in contribution to molecular, cellular, and organismal level function continue to be explored for potential insights into genetic or pathological dysfunction. The EJC’s specific role in the cell cycle and its implications in cancer and neurodevelopmental disorders prompt enhanced investigation of the EJC as a potential target for these diseases. In this review, we highlight the current understanding of the EJC’s position in the cell cycle, its relation to cancer and developmental diseases, and potential avenues for therapeutic targeting

Unveiling the spatial metabolome and anti-atherosclerosis effects of Allium macrostemon Bunge and Allium chinense G. Don

Allium macrostemon Bunge (AMB) and Allium chinense G. Don (ACGD) are both the medicinal herbs of Allii Macrostemonis Bulbus (also named Xiebai in Chinese) for the treatment of coronary heart disease. However, the similarities and differences of anti-atherosclerosis effects and chemical profiles of AMB and ACGD still remain unclear. Similarly, comparative analysis of the spatial metabolomes of AMB and ACGD has rarely been performed. First, biochemical and pathological results demonstrated that AMB and ACGD extracts exhibited similar and close lipid-lowering activity and anti-atherosclerosis effect. Further, a total of 693 metabolites were identified or tentatively characterized by UHPLC-MS/MS and UHPLC-TOF/MS. And 365 differential compounds were determined between AMB and ACGD involving in carbohydrate and aldarate metabolism, purine metabolism, linoleic acid metabolism, α-linoleic acid metabolism, phenylalanine and tyrosine metabolism. Moreover, MALDI-TOF IMS-mediated spatial metabolome given the biosynthesis pathways of steroidal saponins, flavonoids, lignans for the first time. These compounds were rich in AMB tunic and outside scales, whereas they were mainly distributed in ACGD tunic, whole leaf scales, and rarely in developing flower buds. Taken together, these findings provided abundant information about pharmacological effects, chemical profiling and visual spatial distribution of AMB and ACGD, and would benefit the application and promotion of their relative products on the market

Transcriptomic Analyses of Brains of RBM8A Conditional Knockout Mice at Different Developmental Stages Reveal Conserved Signaling Pathways Contributing to Neurodevelopmental Diseases

RNA-binding motif 8A (RBM8A) is a core component of the exon junction complex (EJC) that binds pre-mRNAs and regulates their splicing, transport, translation, and nonsense-mediated decay (NMD). Dysfunction in the core proteins has been linked to several detriments in brain development and neuropsychiatric diseases. To understand the functional role of Rbm8a in brain development, we have generated brain-specific Rbm8a knockout mice and used next-generation RNA-sequencing to identify differentially expressed genes (DEGs) in mice with heterozygous, conditional knockout (cKO) of Rbm8a in the brain at postnatal day 17 (P17) and at embryonic day 12. Additionally, we analyzed enriched gene clusters and signaling pathways within the DEGs. At the P17 time point, between the control and cKO mice, about 251 significant DEGs were identified. At E12, only 25 DEGs were identified in the hindbrain samples. Bioinformatics analyses have revealed many signaling pathways related to the central nervous system (CNS). When E12 and P17 results were compared, three DEGs, Spp1, Gpnmb, and Top2a, appeared to peak at different developmental time points in the Rbm8a cKO mice. Enrichment analyses suggested altered activity in pathways affecting cellular proliferation, differentiation, and survival. The results support the hypothesis that loss of Rbm8a causes decreased cellular proliferation, increased apoptosis, and early differentiation of neuronal subtypes, which may lead ultimately to an altered neuronal subtype composition in the brain

Single-cell and spatial transcriptomics reveals that PTPRG activates the m6A methyltransferase VIRMA to block mitophagy-mediated neuronal death in Alzheimer’s disease

Neuronal death is one of the key pathologies in Alzheimer's disease (AD). How neuronal death begins in AD is far from clear, so clarifying this process may help develop effective therapies. This study collected single-cell RNA sequencing data of 85 AD samples and 83 control samples, covering the prefrontal cortex, internal olfactory cortex, superior parietal lobe, superior frontal gyrus, caudal internal olfactory cortex, somatosensory cortex, hippocampus, superior frontal cortex and peripheral blood mononuclear cells. Additionally, spatial transcriptomic data of coronal sections from 6 AppNL-G-F AD mice and 6 control C57Bl/6 J mice were acquired. The main single-cell and spatial transcriptomics results were experimentally validated in wild type and 5 × FAD mice. We found that the microglia subpopulation Mic_PTPRG can communicate with specific types of neurons (especially excitatory ExNeu_PRKN_VIRMA and inhibitory InNeu_PRKN_VIRMA neuronal subpopulations) and cause them to express PTPRG during AD progression. Within neurons, PTPRG binds and upregulates the m6A methyltransferase VIRMA, thus inhibiting translation of PRKN mRNA to prevent the clearance of damaged mitochondria in neurons through suppressing mitophagy. As the disease progresses, the energy and nutrient metabolic pathways in neurons are reprogrammed, leading to their death. Consistently, we determined that PTPTRG can physically interact with VIRMA in mouse brains and PRKN is significantly upregulated in 5 × FAD mouse brain. Altogether, our findings demonstrate that PTPRG activates the m6A methyltransferase VIRMA to block mitophagy-mediated neuronal death in AD, which is a potential pathway, through which microglia and neuronal PTPRG modify neuronal connections in the brain during AD progression