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In the face of increasing demands for tasks such as mountain rescue, geological exploration, and military operations in complex wilderness environments, planning an efficient walking route is crucial. To address the inefficiency of traditional two-dimensional path planning, this paper proposes a two-stage path planning algorithm. First, an improved Probabilistic Roadmap (PRM) algorithm is used to quickly and roughly determine the initial path. Then, the morphological dilation is applied to process the grid points of the initial path, retaining the surrounding area of the initial path for a precise positioning of the search range. Finally, the idea of the A∗ algorithm is applied to achieve precise path planning in the refined search range. During the process of constructing the topology map, we utilized parallelization acceleration strategies to expedite the graph construction. In order to verify the effectiveness of the algorithm, we used terrain data to construct a wilderness environment model, and tests were conducted on off-road path planning tasks with different terrains and distances. The experimental results show a substantial enhancement in the computational efficiency of the proposed algorithm relative to the conventional A∗ algorithm by 30 to 60 times. [ABSTRACT FROM AUTHOR]

Exploring the spatio-temporal differentiation characteristics and coupling coordination relationship of the composite ecosystem of urban agglomerations is of great significance for promoting the synergistic sustainable development and integration construction of urban agglomerations. This paper is based on LUCC (Land Use and Land Cover Change) data, a DEM (Digital Elevation Model), and temperature, precipitation, and other multi-source data, using the central Yunnan urban agglomeration as an example and constructing a multi-dimensional evaluation index system highlighting development quality and efficiency. The entropy weight method was first used to determine the comprehensive weights to evaluate the regional economic and social development level. Then, the InVEST (Integrated Valuation of Ecosystem Services and Trade-offs) model was used to quantitatively calculate and analyze the spatial and temporal evolution characteristics of the four key ecosystem services, evaluating the spatio-temporal evolution characteristics of the natural subsystem. The coupling coordination model was used to quantitatively analyze the evolution of the coupling coordination of the composite ecosystems in the central Yunnan urban agglomeration during the period of 2010–2020, and to reveal its development law. The results show the following: ➀ During the study period, the socio-economic subsystems in the central Yunnan urban agglomeration demonstrated an outward radiative growth from Kunming City, marked by underdeveloped sub-centers and prevalent low-level areas. ② Trends in ecosystem services varied, with water and soil conservation showing fluctuating increases, carbon sequestration remaining stable, and habitat quality declining. The critically important integrated ecosystem services zone of the natural subsystem is mainly located in the northeastern region and southwestern edge of the study area. ③ In 2020, the coupling coordination degree of the composite ecosystem was 0.9492. This showed that economic, social, and ecological subsystems are highly coupled, with consistent overall development trends and strong interactions. ④ The increase in the degree of harmonization amounted to 7.82%, with lagging subsystems varying in the degree of harmonization in subregions. This study can provide a scientific foundation for the development of policies for the Central Yunnan urban agglomeration, promoting regional sustainable development and optimizing the spatial pattern of the national territory. [ABSTRACT FROM AUTHOR]

OpenStreetMap (OSM) as one of the most successful projects of Volunteered Geographical Information (VGI) has attracted millions of contributors to work together and produces massive open geographical data. However, the co-work does not always run smoothly since mapping can involve conflicted understandings of the reality. In this paper, we investigate behaviors of mapping related to territorial disputes to reveal the characteristics of contributions and examine the contradictions between ground truth as the vision of OSM and the theory of critical cartography. We perform our experiments from the perspectives of entities, changesets, and contributors using the full history data of OSM. The experiments show that territorial-dispute-related contributions have substantially different characteristics from various aspects but they cannot be treated as outliers either, considering that most contributors do not focus on disputed boundaries. Interpreting OSM data as a converging state to ground truth or equally opinions can both be inaccurate. We also find that mapping disputes may not be absolutely negative in a VGI project. We perform quantitative, large-scale (global) analysis of dispute-related mapping. The results show that territorial-dispute-related contributions and contributors are different from contributions and contributors in general. Territorial-dispute-related mapping is not an independent phenomenon for OSM. The contributors make much more disputes-unrelated contributions. Dispute-related entities have more (divergent) versions than normal boundaries, attract more participants, and are more semantically complete, especially for names. Dispute-related changesets generally attract more discussions. The spatial distribution of the dispute-related changesets is consistent with real-world territorial disputes and very different from that of all boundary-related changesets and all changesets. Contributors who participate in dispute-related contributions are generally more active. These users tend to have a special interest in boundaries but most of them do not focus on disputed boundaries. [ABSTRACT FROM AUTHOR]

Spatio-temporal association analysis has attracted attention in various fields, such as urban computing and crime analysis. The proliferation of positioning technology and location-based services has facilitated the expansion of association analysis across spatio-temporal scales. However, existing methods inadequately consider the scale differences among spatio-temporal objects during analysis, leading to suboptimal precision in association analysis results. To remedy this issue, we propose a multiscale spatio-temporal object representation method, STO2Vec, for association analysis. This method comprises of two parts: graph construction and embedding. For graph construction, we introduce an adaptive hierarchical discretization method to distinguish the varying scales of local features. Then, we merge the embedding method for spatio-temporal objects with that for discrete units, establishing a heterogeneous graph. For embedding, to enhance embedding quality for homogeneous and heterogeneous data, we use biased sampling and unsupervised models to capture the association strengths between spatio-temporal objects. Empirical results using real-world open-source datasets show that STO2Vec outperforms other models, improving accuracy by 16.25% on average across diverse applications. Further case studies indicate STO2Vec effectively detects association relationships between spatio-temporal objects in a range of scenarios and is applicable to tasks such as moving object behavior pattern mining and trajectory semantic annotation. [ABSTRACT FROM AUTHOR]

Amide bond is often seen in value-added nitrogen-containing heterocyclic compounds, which can present promising chemical, biological, and pharmaceutical significance. However, current synthesis methods in the preparation of amide-containing N-heterocyclic compounds have low specificity (large amount of by-products) and efficiency. In this study, we focused on reviewing the feasible enzymes (nitrogen acetyltransferase, carboxylic acid reductase, lipase, and cutinase) for the amidation of N-heterocyclic compounds; summarizing their advantages and weakness in the specific applications; and further predicting candidate enzymes through in silico structure-functional analysis. For future prospects, current enzymes demand further engineering and improving for practical industrial applications and more enzymatic tools need to be explored and developed for a broader range of N-heterocyclic substrates. [ABSTRACT FROM AUTHOR]

In efforts to improve regional ecosystem service functions, coordinate land development and ecological conservation, and establish a reference for optimizing land resource allocation and policy formulation to cope with climate change, it is critical to investigate the spatial distribution of land use/cover change (LUCC) and ecosystem services (ESs) under future climate change. This study proposes a framework based on the Shared Socioeconomic Pathway and Representative Concentration Pathway (SSP-RCP), integrating the patch-generating land use simulation (PLUS) model and the integrated valuation of ecosystem services and tradeoffs (InVEST) model to analyze the spatial agglomeration of ESs, to analyze the importance of each driving factors. The results of the study show as follows: (1) the combination of CMIP6 and PLUS models can effectively simulate land use with an overall accuracy of 0.9379. (2) In spatial correlation, ESs show good clustering in all three future scenarios, with similar distribution of cold hotspots in the SSP126 and SSP245 scenarios. Hotspots are more dispersed and cold spots are shifted to the west in the SSP585 scenario. (3) GDP is an important factor in carbon storage and habitat quality, and precipitation has a greater impact on soil retention and water production. Overall, ESs can be increased by appropriately controlling population and economic development, balancing economic development and ecological protection, promoting energy transition, maintaining ecological hotspot areas, and improving cold spot areas. [ABSTRACT FROM AUTHOR]

Reading vector data files to in‐memory data models efficiently is a crucial step to handle the ever‐growing volume of geographical data. Although advanced IO solutions like distributed file systems or Message Passing Interface parallel IO work well in some high‐end computing environments, the 20‐year‐old OGR simple features library is still the de facto tool for loading vector files when developing GIS algorithms in most scenarios, which is not very efficient when data become larger. In this article, we analyze the bottleneck of the OGR library and find that excessive small objects are the main source of slowness. We then offer advice to improve efficiency when using OGR. To further verify our findings and provide an alternative to the OGR library in performance‐sensitive scenarios, we develop a library based on continuous memory pools to avoid small objects. Experiments show that our advice is effective and our library can be several times faster than the OGR library for IO‐intensive programs. [ABSTRACT FROM AUTHOR]

Oblique photogrammetry models are indispensable for implementing digital twins of cities. Geographic information system researchers have proposed plenty of methods to load and visualize these city-scaled scenes. However, when the area viewed changes quickly in real-time rendering, current methods still require excessive GPU calculation and memory occupation. In this study, we propose a data organization method in which we merged all quadtrees and used a binary encoding method to encode nodes in a merged tree so that the parent–child relationship between the tree nodes could be calculated using rapid binary operations. After that, we developed a strategy to cancel the loading of redundant nodes based on the parent–child relationship, which helped to reduce the hard disk loading time and the amount of memory occupied in visualization. Moreover, we introduced a parameter to measure the area of the triangle mesh per pixel to achieve unified data scheduling under different production standards. We implemented our method based on Unreal Engine (UE), and three experiments were designed to illustrate the advantages of our methods in index acceleration, frame time, and memory reduction. The results show that our methods can significantly improve visualization fluency and reduce memory usage. [ABSTRACT FROM AUTHOR]

In the big data era, rapid visualization of large-scale vector data has become a serious challenge in Geographic Information Science (GIS). To fill the gap, we propose HiIndex, a spatial index that enables real-time and interactive visualization of large-scale vector data. HiIndex improves the state of the art with its low memory requirements, fast construction speed, and high visualization efficiency. In HiIndex, we present a tile-quadtree structure (TQ-tree) which divides the global geographic range based on the quadtree recursion method, and each node in the TQ-tree represents a specific and regular spatial range. In this paper, we propose a quick TQ-tree generation algorithm and an efficient visualization algorithm. Experiments show that the HiIndex is simple in structure, fast in construction, and less in memory occupation, and our approach can support interactive and real-time visualization of billion scale vector data with negligible pre-treatment time. [ABSTRACT FROM AUTHOR]

Postmenopausal women taking estrogen supplements are at a lower risk of advanced colorectal cancer, but the underlying mechanism remains unclear. Thus, this study examined the role of estrogen in colorectal cancer. Estrogen receptor expression levels in in situ colorectal cancer tissue from female patients increased significantly, indicating their estrogen sensitivity. Compared with the sham-operated group, the growth of MC38 tumors was enhanced in ovariectomized mice, which was reversed in ovariectomized mice with E2 supplementation. The PD-L1+ M2-like macrophage, regulatory T (Treg) cell, and myeloid-derived suppressor cell (MDSC) populations significantly increased, and the population of cytotoxic CD8+ T cells declined in MC38 tumors in ovariectomized mice, which were all reversed in ovariectomized mice with E2 supplementation. MC38 cell-derived extracellular vesicles (MC38-EVs), but not EVs derived from MC38 cells treated with E2 (E2-MC38-EVs), were involved in the establishment of immunosuppressive tumor microenvironment. E2-MC38-EVs contained lower TGF-β1 levels and were less capable of inducing Treg cells than MC38-EVs in vitro. Overall, these results show that estrogen treatment prevents MC38 tumor growth via regulating the tumor immune microenvironment through MC38-EVs. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA), a homopolymer of lactic acid (LA), is a bio-derived, biocompatible, and biodegradable polyester. The evolved class II PHA synthase (PhaC1 Ps 6-19 ) was commonly utilized in the de novo biosynthesis of PLA from biomass. This study tested alternative class I PHA synthase (PhaC Cs ) from Chromobacterium sp. USM2 in engineered Escherichia coli for the de novo biosynthesis of PLA from glucose. The results indicated that PhaC Cs had better performance in PLA production than that of class II synthase PhaC1 Ps 6-19 . In addition, the sulA gene was engineered in PLA-producing strains for morphological engineering. The morphologically engineered strains present increased PLA production. This study also tested fused propionyl-CoA transferase and lactate dehydrogenase A (fused Pct Cp /LdhA) in engineered E. coli and found that fused Pct Cp /LdhA did not apparently improve the PLA production. After systematic engineering, the highest PLA production was achieved by E. coli MS6 (with PhaC Cs and sulA ), which could produce up to 955.0 mg/L of PLA in fed-batch fermentation with the cell dry weights of 2.23%, and the average molecular weight of produced PLA could reach 21,000 Da., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Shi, Li, Yang, Miao, Yang, Pandhal and Zou.)

Extracellular vesicles derived from trophoblasts (T-EVs) play an important role in pregnancy, but the mechanism is not entirely clear. In this study, we found that HLA-E, which is mostly confined to the cytoplasm of trophoblast cells, was secreted by T-EVs. The level of HLA-E in T-EVs from unexplained recurrent spontaneous abortion (URSA) patients was lower than that in normal pregnancy (NP) and RSA patients who had an abnormal embryo karyotype (AK-RSA). T-EVs promoted secretion of IFN-γ and VEGFα by decidual NK (dNK) cells from URSA patients via HLA-E, VEGFα was necessary for angiogenesis and trophoblast growth, and IFN-γ inhibited Th17 induction. Glycolysis and oxidative phosphorylation (OxPhos) were involved in this process. Glycolysis but not OxPhos of dNK cells facilitated by T-EVs was dependent on mTORC1 activation. Inhibition of T-EV production in vivo increased the susceptibility of mice to embryo absorption, which was reversed by transferring exogenous T-EVs. T-EVs promoted secretion of IFN-γ and VEGFα by dNK cells to maintain pregnancy via Qa-1 in abortion-prone mouse models. This study reveals a new mechanism of pregnancy maintenance mediated by HLA-E via T-EVs., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)