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The many-banded krait, Bungarus multicinctus , has been recorded as the animal resource of JinQianBaiHuaShe in the Chinese Pharmacopoeia. Characterization of its venoms classified chief phyla of modern animal neurotoxins. However, the evolutionary origin and diversification of its neurotoxins as well as biosynthesis of its active compounds remain largely unknown due to the lack of its high-quality genome. Here, we present the 1.58 Gbp genome of B. multicinctus assembled into 18 chromosomes with contig/scaffold N50 of 7.53 Mbp/149.8 Mbp. Major bungarotoxin-coding genes were clustered within genome by family and found to be associated with ancient local duplications. The truncation of glycosylphosphatidylinositol anchor in the 3′-terminal of a LY6E paralog released modern three-finger toxins (3FTxs) from membrane tethering before the Colubroidea divergence. Subsequent expansion and mutations diversified and recruited these 3FTxs. After the cobra/krait divergence, the modern unit-B of β -bungarotoxin emerged with an extra cysteine residue. A subsequent point substitution in unit-A enabled the β -bungarotoxin covalent linkage. The B. multicinctus gene expression, chromatin topological organization, and histone modification characteristics were featured by transcriptome, proteome, chromatin conformation capture sequencing, and ChIP-seq. The results highlighted that venom production was under a sophisticated regulation. Our findings provide new insights into snake neurotoxin research, meanwhile will facilitate antivenom development, toxin-driven drug discovery and the quality control of JinQianBaiHuaShe. Post ancient duplication mutations shaped modern neurotoxins in the many-banded krait. [Display omitted] [ABSTRACT FROM AUTHOR]

Mega city regions (MCRs) have emerged in many countries in the process of urbanisation. Understanding the spatio-temporal dynamics of MCRs is crucial for sustainable urban development. However, the spatial scales and boundaries of these MCRs remain poorly defined, and their temporal dynamics have received limited attention. To address these gaps, we propose a new framework and GSMA algorithm that considers inter-city flows to identify MCRs' central cities, ranges and hinterlands. By utilising comprehensive data of over 30 million inter-city flow records covering 369 cities from Amap and Tencent, calibrated with official data from the Ministry of Transport, we identify 10 MCRs and 16 central cities in China, providing a clearer understanding of the spatial ranges and core areas of MCRs. We find that MCR ranges show relative stability during routine activities and expansions during holiday periods. Compared with previous methods, the proposed framework and algorithm have two prominent advantages. First, our methodology incorporates the directional characteristics of flows into the identification of MCRs' central cities. Second, we strike a balance between enlarging regional influence and tightening the internal connections in MCR delineation. In addition, by incorporating temporal changes in inter-city flows, the study reveals the temporal dynamics of MCRs which reflects the intricate interplay between human activities and urban system dynamics. • A new GSMA algorithm is proposed to identify central cities, ranges, and hinterlands of mega city regions (MCRs). • Analysis of 30 million inter-city flow records reveals evolving patterns of MCR spatial scales in China. • MCR ranges exhibit relative stability and expand during weekends and holidays. [ABSTRACT FROM AUTHOR]

This study investigates the slip system activities in primary α grains of a forged Ti–6Al–4V alloy under pure fatigue and dwell-fatigue conditions, using high-resolution digital image correlation (HR-DIC) analysis obtained through interrupted mechanical tests. A quantitative examination of operating slip systems and strain localization on large-field HR-DIC data is conducted using an automated analysis framework developed in a previous study. The findings reveal higher slip activities under dwell-fatigue conditions, evidenced by parameters such as slip band density, area fraction of grains activated with slips, and mean equivalent plastic strain intensities along slip bands through statistically sound analysis. A notable shift in dominant slip activity from basal slips to prismatic slips is observed under pure fatigue conditions, while dominant prismatic slip activity persists throughout dwell-fatigue processes. Furthermore, slip bands with early-developed high strain localization, referred to as slip markings, are identified as prerequisites for surface crack initiation, and three types of slip markings are discovered. Finally, possible reasons for dwell-life debits, and potential anisotropy in the two major slip systems, basal and prismatic slips, are discussed. • Slip system activities are analyzed for bimodal Ti–6Al–4V under pure fatigue and dwell-fatigue conditions. • Quantitative analysis on slip band activities is obtained through large-field HR-DIC data. • Similarities and differences in slip band activities are identified for different conditions. • Cracks are observed on slip band with early developed high strain localization in dwell-fatigue. • Anisotropic slip behaviors between basal and prismatic slips are discovered. [ABSTRACT FROM AUTHOR]

• We investigate the impact of credit card accessibility on household labor participation in China. • Credit card usage has played a significantly beneficial role. • Paying off credit card debt could function as a potential mechanism. • Having a credit card may also increase work intensity and stimulate entrepreneurial activity. Using two-wave panel data from the China Household Finance Survey (CHFS), this study aims to examine the impact of credit card access on household labor participation in China. The findings reveal a significant positive relationship between credit card use and labor market decision, even after addressing concerns related to endogeneity and conducting various robustness checks. Moreover, it suggests that the act of paying off credit debt could serve as a potential mechanism that motivates household members to join the workforce. There is further evidence indicating that carrying a credit card may enhance work intensity and boost entrepreneurial activity. [ABSTRACT FROM AUTHOR]

Traffic congestion is one of the key issues relating to sustainability and livability in many large cities. In particular, the situation in the growing megacities of developing countries has been worsening and is now attracting considerable attention from researchers and politicians. An understanding of the spatio-temporal patterns of this congestion is necessary in order to formulate effective policies to relieve it. Much of the research to date has focused on single districts for relatively short periods (days or weeks) using GPS, while long-term analysis of spatial and temporal patterns of traffic congestion at the city level has been rare. The aim of this paper is to help fill this gap in the literature by applying a big data analytic approach to a sample of 10.16 million records of traffic congestion indexes for 233 roads in the Beijing area over a six-month period. This analysis revealed four typical traffic congestion patterns in Beijing, which can be described as the weekend mode, holiday mode, weekday mode A, and weekday mode B. Each of these patterns possesses unique spatial and temporal characteristics. Compared with working days, on which congestion is regular and agglomerated, weekends and holidays are characterized by long-lasting congestion peaks throughout the day. Non-commuting travel on weekends and holidays, including trips for tourism, shopping, entertainment, and children's after-school activities, are major contributors to traffic congestion of the weekend and holiday mode. Owing to poor jobs-housing balance, the suburban new towns and job centres had relatively higher congestion than other areas. These findings shed significant light on geographical patterns of traffic congestion in growing megacities. • Traffic congestion is a key issue relating to urban sustainability. • This paper apples a big data analytic approach to a sample of 10.16 million records of traffic congestion. • There are four typical traffic congestion patterns in Beijing. • No-commuting travels on weekends and holidays are major contributors to traffic congestion. • The suburban new towns and job centres had relatively higher congestion. [ABSTRACT FROM AUTHOR]

Statistical analysis of slip system identification and quantitative study on local plasticity is crucial to understand the collective deformation by the sub-grain-scale slip activities in polycrystalline metallic materials. In this study, an automated framework for identifying slip system and assessing strain localization of slip bands termed ASSISL (automated Slip System Identification and Strain Localization analysis of slip bands) is introduced, using the results from high resolution digital image correlation (HR-DIC), and is demonstrated on 1591 primary α grains of a bimodal Ti-6Al-4V alloy under tensile loading. The framework includes: (1) alignment of electron backscattered diffraction (EBSD) maps with strain field maps from HR-DIC through treatment of EBSD distortion, (2) slip band orientations identification from strain field map of each grain through a Radon-transform-based algorithm, (3) slip system assignment with combined Schmid factor and critical resolved shear stress analysis, (4) quantification of plasticity by slip activities which provides information on the numbers, positions and mean strain of slip bands in each grain. The confidence of ASSISL is validated through comparing current statistical results with existing literature, as well as examining reasons for grains assigned with wrong slip systems, which accounts for 9.6 percent (153 out of 1591) of the primary α grains. A comparison between ASSISL and other HR-DIC-based slip identification methods is also conducted. This framework provides a method for analyzing slip activities in a large number of grains of polycrystalline metals in a time-saving and automated fashion. • An automated slip analysis framework termed ASSISL using strain field maps from HR-DIC is developed. • Statistical analysis obtained from ASSISL is demonstrated on 1591 primary α grains of a Ti-6Al-4V alloy. • Comparisons among ASSISL and other HR-DIC-based slip system identification methods are presented. • ASSISL could be applied to other metals for automated slip trace and strain localization analysis. [ABSTRACT FROM AUTHOR]

Using the Broadband China strategy as a quasi-natural experiment, our study attempts to understand how broadband infrastructure (BI) impacts entrepreneurship in China. Employing a staggered difference-in-difference approach, we argue that BI significantly enhances entrepreneurship, and that this conclusion holds after considering the identification of assumptions and a range of other factors that may interfere with the estimation results. The mechanism exploration reveals that human capital agglomeration and financial development are the main pathways through which BI encourages entrepreneurial activities. Furthermore, the positive effects of BI are bigger in eastern cities, high market-oriented cities, and among cities with excellent traditional infrastructure. Our findings reveal the role of improving BI in facilitating the development of new ventures in China. • This paper estimates the causal effect of broadband infrastructure on entrepreneurship. • We exploit the launch of Broadband China strategy as a quasi-natural experiment. • Broadband infrastructure has had a significant beneficial role. • Potential mechanisms include human capital agglomeration and financial development. • Broadband infrastructure effects on entrepreneurship are heterogeneous. [ABSTRACT FROM AUTHOR]

Countries have invested in transport infrastructure and public service in recent years to reduce rural poverty and income inequality. However, the effects of transport infrastructure on the residents with economic and educational disadvantages in rural areas are still under debate. In this paper, we investigate the impact of road infrastructure on the income of rural residents at the municipal level using data from the China Family Panel Survey (CFPS) from 2010 to 2018. By using the instrumental variable regression model, we found that rural residents' household incomes benefit from road infrastructure. Within income components, road infrastructure plays a role in improving rural residents' wage and business income. Further comparing different rural resident groups, we found that rural residents with lower initial farming and business income benefit more from improved road infrastructure in terms of their farming and business income from 2010 to 2018. In addition, in poverty-stricken areas, rural residents with lower initial farming and business income benefit more from road infrastructure in improving their farming and business income. However, the household incomes of rural residents with low formal education improve less as a result of road infrastructure. Policymakers should thus consider combining transport infrastructure provision with other policy packages, such as education program or skill training, to target different groups of rural residents in China. • Explaining the relationship between road infrastructure and rural residents' income. • Rural residents with lower initial farming and business income benefit more from improved road infrastructure. • In poverty-stricken areas, rural residents with lower initial farming and business income benefit more from road infrastructure. [ABSTRACT FROM AUTHOR]

Lithium-ion capacitors (LIC) have problems such as the imbalance of electrochemical kinetics between the battery-type anode and the capacitive cathode, and the large change in the working potential of the hard carbon anode during charge and discharge, which limit the improvement of electrochemical performance for LIC. To solve these problems, CoSe 2 nanoparticles embedded nitrogen-doped hard carbon microspheres (NCS-CoSe 2) are synthesized and used as the anode material of LIC. Electrochemical tests show that NCS-CoSe 2 has a reversible specific capacity of as high as 500 mAh g−1 at a current density of 1 A g−1, which can effectively stabilize the working potential of the anode. At a high working voltage window of 2.2–4.5 V, the potential change of the NCS-CoSe 2 anode is as low as 0.35 V, significantly smaller than that of the pure hard carbon (0.87 V). Regarding the electrode kinetics, the NCS-CoSe 2 anode is matched with the active carbon cathode well. When the power density rises sharply from 335 W kg−1 to 6700 W kg−1, the energy density of NCS-CoSe 2 //AC LIC can attain 82 Wh kg−1 (56.9% of initial energy density). Image, graphical abstract [ABSTRACT FROM AUTHOR]

• A light-powered liquid crystal elastomer semi-rotary motor is proposed. • Two motion modes distinguished as the static mode and the self-rotation are presented. • The influences of system parameters on the triggering conditions, frequency and amplitude of self-rotation are investigated. • Results provide a reference for the design and control of self-rotating LCE semi-rotary motor. Self-excited oscillators are characterized by active energy harvesting from the stable external environment, autonomy and portability, which allow them to act as engines to drive other working devices. Taking inspiration from the pump drill, a semi-rotary motor consisting of a motor rotor and three liquid crystal elastomer (LCE) fibers is constructed in this paper, which can realize self-rotation under stable illumination. Considering the existing twisted wire model and the dynamic LCE model, a nonlinear dynamics model for the semi-rotary motor under stable illumination is established. Numerical calculations witness the existence of two motion modes for the semi-rotary motor under stable illumination, namely the static mode and the self-rotation mode. Under stable illumination, the light-driven contraction of twisted segments in LCE fibers for the winding state can trigger the self-rotation and maintain the continuous periodic motion through the interrelationship between optical energy and damping dissipation. The critical conditions required to trigger the self-rotation are also investigated in detail, as well as the crucial system parameters affecting the self-rotation frequency and amplitude. The proposed self-rotating semi-rotary motor has a simple structure, customizable dimensions and high speed, prompting its potential use in soft robots, energy harvesters, and micro-machines. [ABSTRACT FROM AUTHOR]

In polycrystalline austenitic stainless steels, a comprehensive three-dimensional configuration of crystal plasticity in relation to microstructure is required to elucidate the deformation behaviors during mechanical loading. In the present work, a combination of backscattered electron image (BSE) based high-resolution digital image correlation (HR-DIC) and laser scanning confocal microscopy (LSCM) was employed to simultaneously investigate in-plane and out-of-plane deformations at the sub-grain scale in 316 stainless steel. The high spatial resolution and precise alignment provided by the three-dimensional deformation assessment enable the identification of specific slip and twinning systems. This is achieved through the minimization of the residual L 2 norm between the in-plane components of experimental and theoretical strain tensors. Dominant slip and few mechanical twinning activities are initiated at the early-stage of yielding, and their frequency and intensity increase with the applied load. The hierarchical networks formed by nanotwins, along with the presence of grain and annealing twin boundaries, serve as obstacles for slip glide, leading to substantial twin–slip interaction and grain boundary strengthening. As a consequence of wide mechanical twins formed by parallel nanotwins coalescence and strain localization at the twin boundary, slip transmission occurs, resulting in an effective accommodation of external stress. Furthermore, the consistent observation of out-of-plane roughness, in alignment with twinning Burgers vector predictions, offers valuable insights into the significant deformation gradient occurring in the vicinity of boundaries. This deformation gradient is influenced by the neighboring mechanical twinning activities, indicating strong obstacle to twin transmission and high back-stresses resulting from the highly misoriented grain boundary. • Three-dimensional configuration of crystal plasticity was assessed by HR-DIC and LSCM. • Slip and twinning systems were identified through the minimization of residual L 2 norm. • Slip transmissions were observed at annealing twin boundaries and deformation twins. • Consistent observation of out-of-plane roughness with Burgers vector prediction provided an insight into the pronounced deformation gradient in boundary vicinities. [ABSTRACT FROM AUTHOR]

Ultrafine grained medium Mn steel exhibits simultaneous high strength and ductility, however, often showing Lüders deformation and discontinuous yielding phenomena. The connections between martensite transformation and Lüders deformation as well as the localized failure behavior are quantitatively investigated through high resolution digital image correlation, enabled by nanoscale strain distribution and microstructural alignment. At a low global tensile strain level, strain localization happens in austenite domain resulted from a sequential slip deformation and martensite transformation, which then triggers the yielding of ferrite by generating thin strain channels to connect adjacent hotspots. This microscopic deformation mode promotes the formation of macroscopic deformation bands, resulting in Lüders band initiation and propagation. When increasing the applied load, the externally imposed strain is accommodated by ferrite instead, resulting in pronounced strain partitioning. The triple grains boundary having no further strain hardening capacity is favorable for void initiation and propagation. [ABSTRACT FROM AUTHOR]

Although the effects of transport infrastructure on regional development have been widely discussed, the relationship between transport infrastructure and urban–rural income disparities has scarcely been examined. This study provides new evidence of those disparities by looking at 227 prefectural-level cities in China in 2016. We found that national, provincial and municipal roads played a positive role in narrowing the urban–rural income gap by facilitating rural labour mobility. The high coefficient of provincial and municipal roads indicates that they provide access to local and regional job markets for migrant farmers. The impact of roads is most remarkable in China's southwestern and middle regions, demonstrating that road infrastructure is more important for rural residents in these regions to increase their income. The least significant impact of road infrastructure was found in the northeast region, where road infrastructure is not the main restriction factor for its development. Policymakers should consider the impact of road infrastructure in different regions to reduce the urban–rural income gap. [ABSTRACT FROM AUTHOR]

• This paper examines the time-varying accessibility to senior centers by public transit in Philadelphia using the GTFS data. • Accessibility to senior centers declines from the downtown to the suburbs. • Neighborhoods with higher shares of older adults tend to have lower accessibility to senior centers. • Neighborhoods with higher shares of households having zero cars are better served. • Neighborhoods with higher shares of African Americans and Hispanics are less well served. Public transit offers older adults an important alternative travel mode for accessing social activity destinations. Given the growing size and socioeconomic diversity of the older population, transportation planners should consider how current urban transit systems can better meet their needs. In this study, we examine the time-varying accessibility to senior centers by public transit in each census tract of Philadelphia, Pennsylvania. Senior centers are community service and activity hubs for older adults which are typically overseen by the local area agency on aging. They offer a variety of services and social activities for older adults, including free meals, volunteering opportunities, information, and technology training. Using General Transit Feed Specification (GTFS) data and socioeconomic data from the U.S. Census Bureau, we analyze how accessibility varies across census tracts with respect to the tract's share of older adults, particularly those in vulnerable subgroups. We found that accessibility to senior centers declines from the downtown area to the suburbs but varies considerably among the vulnerable subgroups studied. We also found that when accounting for the open hours of senior centers, accessibility to senior centers is generally lower around midday (2 PM) than during peak hours (8:30 AM) on Mondays. We used the vertical equity index to examine social disparities in accessibility among older adults. We found that while SEPTA underserves neighborhoods with higher shares of older adults, tracts with higher shares of some vulnerable subgroups are better served than those with lower shares. Specifically, neighborhoods with higher shares of households that have no cars are better served than those with higher shares of African American and Hispanic older adults. These results suggest that the Southeastern Pennsylvania Transportation Authority (SEPTA) and the Philadelphia Corporation for Aging (PCA) should work together to better accommodate the diverse travel needs of older adults. [ABSTRACT FROM AUTHOR]

Cylindrical organs, e.g., blood vessels, airways, and intestines, are ubiquitous structures in biomedical optical imaging analysis. Image segmentation of these structures serves as a vital step in tissue physiology analysis. Traditional model-driven segmentation methods seek to fit the structure by constructing a corresponding topological geometry based on domain knowledge. Classification-based deep learning methods neglect the geometric features of the cylindrical structure and therefore cannot ensure the continuity of the segmentation surface. In this paper, by treating the cylindrical structures as a 3D graph, we introduce a novel contour-based graph neural network for 3D cylindrical structure segmentation in biomedical optical imaging. Our proposed method, which we named CylinGCN, adopts a novel learnable framework that extracts semantic features and complex topological relationships in the 3D volumetric data to achieve continuous and effective 3D segmentation. Our CylinGCN consists of a multiscale 3D semantic feature extractor for extracting inter-frame multiscale semantic features, and a residual graph convolutional network (GCN) contour generator that combines the semantic features and cylindrical topological priors to generate segmentation contours. We tested the CylinGCN framework on two types of optical tomographic imaging data, small animal whole body photoacoustic tomography (PAT) and endoscopic airway optical coherence tomography (OCT), and the results show that CylinGCN achieves state-of-the-art performance. Code will be released at https://github.com/lzc-smu/CylinGCN.git. • First contour-based model for cylinder-object segmentation in bio-optical imaging. • CylinGCN fuses local semantic and object topology for accurate segmentation. • Attention mechanism, customized graph structure and loss functions are introduced. • CylinGCN achieves state-of-the-art performance in PAT and OCT imaging datasets. [ABSTRACT FROM AUTHOR]

The threat of global climate change has caused the international community to pay close attention to atmospheric levels of greenhouse gases such as carbon dioxide. Transportation sector carbon dioxide emissions efficiency (TSCDEE) is a key indicator used to prioritize sustainable development in the transportation sector. In this paper, the epsilon-based measure data envelopment analysis model with undesirable outputs is applied to estimate TSCDEE for 30 provinces in China from 2010 to 2016. We also analyze influencing factors using the spatial Durbin model. Research shows that the overall TSCDEE of the Chinese provinces studied was 0.618, indicating that most regions are still in need of improvements. The provinces with the highest TSCDEE are located in developed coastal regions of China. This study shows that factors such as transportation structure, traffic infrastructure level, and technological progress have prominent positive effects on TSCDEE, while both urbanization level and urban population density exert significantly negative effects on TSCDEE. The findings should have a far-reaching impact on the sustainable development of global transportation. [Display omitted] • Providing more accurate method in estimating CO 2 emissions of the transport sector. • Focusing on the transportation sector carbon dioxide emissions efficiency (TSCDEE). • Technological progress is the key to improve TSCDEE among different factors in China. • Higher mode share of water and rail transport contributes to higher TSCDEE in China. • Urbanization presents significantly negative effect on TSCDEE in China. [ABSTRACT FROM AUTHOR]

Polythiophene (Pth) is a good candidate cathode material for aluminum ion battery (AIB) because of its lightness, safety, plasticity and flexibility. However, it always manifests inferior stability. Herein, a stable Pth-based cathode is realized through the anchoring effect between Pth and carboxyl. Pth with a thin film morphology is in situ synthesized on the surface of carboxylated carbon nanotubes (CNT-COOH). As a support, CNT-COOH not only alleviates the agglomeration of Pth that provides abundant transport channels for ions and electrons simultaneously, but also enhances the stability of Pth through the anchoring effect. As a result, the prepared Pth/CNT-COOH composite exhibits high discharge capacity (113 mAh g−1 at 1 A g−1), outstanding rate performance (95 mAh g−1 at 5 A g−1) and stable cycle stability (10,000 cycles with 0.001% decay per cycle). This work realizes a promising Pth-based AIBs with high capacity and long lifespan, which paves the way to the applications of organic materials in AIBs. [ABSTRACT FROM AUTHOR]