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Immunoglobulin family and carbohydrate vascular addressins encoded by Madcam1 and St6gal1 control lymphocyte homing into intestinal tissues, regulating immunity and inflammation. The addressins are developmentally programmed to decorate endothelial cells lining gut post-capillary and high endothelial venules (HEV), providing a prototypical example of organ- and segment-specific endothelial specialization. We identify conserved NKX-COUP-TFII composite elements (NCCE) in regulatory regions of Madcam1 and St6gal1 that bind intestinal homeodomain protein NKX2-3 cooperatively with venous nuclear receptor COUP-TFII to activate transcription. The Madcam1 element also integrates repressive signals from arterial/capillary Notch effectors. Pan-endothelial COUP-TFII overexpression induces ectopic addressin expression in NKX2-3+ capillaries, while NKX2-3 deficiency abrogates expression by HEV. Phylogenetically conserved NCCE are enriched in genes involved in neuron migration and morphogenesis of the heart, kidney, pancreas and other organs. Our results define an NKX-COUP-TFII morphogenetic code that targets expression of mucosal vascular addressins.

Research Summary: Acquisitions can shift the market structure of a digital platform in ways that affect subsequent entries and hence the platform's base of complementors. Synergies that complementor acquirers accrue can be entry‐deterring. We develop a two‐by‐two typology of acquisition synergies in a multisided platform based on the two sides of a platform market (user side or complementary‐technology side) and two sources of synergies (economies of scale or economies of scope). We then leverage over 279,000 app developers' entry decisions into product categories in Apple's iOS App Store, over 71 million customer reviews, and over 12,000 unique software development kits to construct measures of synergies. Our paper contributes to the platform literature by demonstrating the entry‐deterring effects of synergies that complementor acquirers can exploit. Managerial Summary: We develop the following typology of four types of acquisition synergies by integrating the multisidedness feature of digital platforms with the mainstream strategy research: complementary‐technology‐side economies of scope, complementary‐technology‐side economies of scale, user‐side economies of scope, and user‐side economies of scale. We show that (1) acquisition synergies are entry‐deterring, (2) synergies derived from economies of scope have stronger effects than those derived from economies of scale, and (3) synergies derived from the technology side have stronger effects than those derived from the user side. We highlight the significant competitive and regulatory implications of our findings. For example, one standard‐deviation increase in technology‐side economies of scope is associated with 55 deterred entries in 1 month or a $2.80 million potential loss in annual revenue. [Correction added on 15 July 2024, after first online publication: Research Summary and Managerial Summary have been corrected in this version.] Video abstract [ABSTRACT FROM AUTHOR]

Large-scale infrastructure projects involve numerous complex processes, and even small construction management (CM) deficiencies can lead to significant resource waste. Digital twins (DTs) offer a potential solution to the management side of the problem. The current DT models focus on real-time physical space mapping, which causes the fragmentation of process data in servers and limits lifecycle algorithm implementation. In this paper, we propose a DT framework that integrates process twins to achieve process discovery through process mining and that serves as a supplement to DTs. The proposed framework was validated in a highway project. Based on BIM, GIS, and UAV physical entity twins, construction logs were collected, and process discovery was performed on them using process mining techniques, achieving process mapping and conformance checking for the process twins. The main conclusions are as follows: (1) the process twins accurately reflect the actual construction process, addressing the lack of process information in CM DTs; (2) process variants can be used to analyze abnormal changes in construction methods and identify potential construction risks in advance; (3) sudden changes in construction nodes during activities can affect resource allocation across multiple subsequent stages; (4) process twins can be used to visualize construction schedule risks, such as lead and lag times. The significance of this paper lies in the construction of process twins to complement the existing DT framework, providing a solution to the lost process relationships in DTs, enabling better process reproduction, and facilitating prediction and optimization. In future work, we will concentrate on conducting more in-depth research on process twins, drawing from a wider range of data sources and advancing intelligent process prediction techniques. [ABSTRACT FROM AUTHOR]

This study investigates countercurrent air-water two-phase flow in vertical pipes with inner diameters of 26 mm and 44 mm and a height of 2000 mm, under controlled conditions to eliminate heat and mass transfer. Cutting-edge techniques were employed to measure the liquid film thickness (δ) and entrainment (e) within the annular flow pattern. The methodology involved a systematic comparative analysis of experimental results against established models, identifying the most accurate methods for predicting flow behavior. Specifically, the Schubring et al. correlation was found to most accurately predict e in 26 mm pipes, while the Wallis correlation was more accurate for 44 mm pipes. Additionally, interfacial shear stress was analyzed, confirming the high precision of the δ and e parameters. This research enhances the understanding of countercurrent air-water two-phase flow by providing reliable estimation methods for different pipe diameters and emphasizes the significance of accurately determining interfacial shear stress. Key findings include the identification of the most accurate models for different pipe sizes and addressing challenges in measuring δ and e under controlled conditions. The study's novelty lies in its comprehensive comparative analysis of existing models, leading to improved predictions of flow dynamics in vertical pipes, thereby contributing valuable insights into two-phase flow behavior in geosciences and environmental engineering. [ABSTRACT FROM AUTHOR]

Gate‐controlled activities in lakes can directly or indirectly influence the assembly of waterbird communities. Shengjin Lake, a Ramsar site, is a typical river‐connected and gate‐controlled shallow lake in the lower and middle Yangtze River floodplain in China, comprising three sub‐lakes (upper, middle, and lower) based on topographical features. We surveyed wintering waterbirds at Shengjin Lake from October 2022 to March 2023. We divided the winter water level period into nine phases based on the characteristics of water level changes. By measuring functional diversity, we aimed to provide insights into the differences in waterbird communities among the three sub‐lakes under different water level conditions. Multiple linear regression was used to analyze the relationship between habitat factors and functional diversity. We further explored the relationship between specific functional traits and habitat factors through a combination of the R‐mode linked to the Q‐mode and the trait‐environment correlation matrix (fourth‐corner analyses) to explain the mechanism underlying waterbird community assembly. When the water level fluctuated in the range of 10.43–10.74 m (Huanghai elevation), the three sub‐lakes had significant habitat differences and high habitat heterogeneity, increasing functional richness and functional dispersion of the upper and lower lakes, both of which significantly differed from those of the middle lake. Habitat heterogeneity and mudflat habitats have positive effects on functional diversity. The difference in functional diversity was primarily determined based on the foraging traits and strata of waterbirds. Habitat filtering of particular traits is a major driving force underlying the assembly of waterbird communities. Overall, we suggest that the minimum water level in the wintering period at Shengjin Lake should be regulated between 10.43 and 10.74 m. These findings provide reasonable suggestions for water level regulation and a theoretical basis for conserving waterbird diversity at Shengjin Lake. [ABSTRACT FROM AUTHOR]

The safety of lunar landing sites directly impacts the success of lunar exploration missions. This study develops a data-driven predictive model based on machine learning, focusing on engineering safety to assess the suitability of lunar landing sites and provide insights into key factors and feature representations. Six critical engineering factors were selected as constraints for evaluation: slope, elevation, roughness, hillshade, optical maturity, and rock abundance. The XGBoost model was employed to simulate and predict the characteristics of landing areas and Bayesian optimization was used to fine-tune the model's key hyperparameters, enhancing its predictive performance. The results demonstrate that this method effectively extracts relevant features from multi-source remote sensing data and quantifies the suitability of landing zones, achieving an accuracy of 96% in identifying landing sites (at a resolution of 0.1° × 0.1°), with AUC values exceeding 95%. Notably, slope was recognized as the most critical factor affecting safety. Compared to assessment processes based on Convolutional Neural Networks (CNNs) and Random Forest (RF) models, XGBoost showed superior performance in handling missing values and evaluating feature importance accuracy. The findings suggest that the BO-XGBoost model shows notable classification performance in evaluating the suitability of lunar landing sites, which may provide valuable support for future landing missions and contribute to optimizing lunar exploration efforts. [ABSTRACT FROM AUTHOR]