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Climate change is increasingly exacerbating water shortages worldwide. Among the various repercussions of water scarcity, notably in developing countries, the most critical are the decline in social sustainability and the widening inequality within farming communities. In response, irrigation reforms aimed at establishing farmer-managed networks have been introduced to foster equitable water distribution and enhance the livelihood and food security of underprivileged farmers. However, these reforms have largely fallen short of achieving their social sustainability goals. A significant factor in this shortfall is the farmers' limited capacity and reluctance to assume roles typically filled by bureaucracy under institutional reforms. This study explores farmers' willingness to engage in a World Bank-assisted participatory irrigation infrastructure program. We utilized questionnaire surveys and hierarchical analysis to evaluate how various factors influence farmers' willingness to participate. The findings indicate a multifaceted challenge that intensifies in communities fragmented by socioeconomic and political divides. Particularly, the predominance of large landowners in agricultural communities and the absence of sufficient bureaucratic support for participation are key impediments. Our research offers comprehensive insights into the regional sociopolitical obstacles obstructing farmer involvement in government-led participatory projects. It also guides policymakers in grasping the intricate interplay between program design, execution, and contextual elements, which is crucial for the sustainable development of resource-stressed areas. [ABSTRACT FROM AUTHOR]

Objective. The purpose of this meta-analysis was to investigate the effect of periprocedural myocardial injury (PPMI) on long-term all-cause mortality in patients undergoing transcatheter aortic valve replacement (TAVR) and to explore potential factors associated with mortality risk. Design. The PubMed, Embase, and Cochrane Library databases were searched up to April 2022. Studies reporting the effect of PPMI on the risk of long-term all-cause mortality were included. The summary odds ratio (OR) was calculated using a random effects model. Additionally, meta-regression and subgroup analyses were conducted according to specific research characteristics to explore sources of heterogeneity. Results. Fourteen studies involving 6,415 patients who underwent TAVR showed that the occurrence of PPMI was associated with a higher risk of long-term mortality. Subgroup analysis showed that in the group of aged ≥82 years, men accounted for less than 50%, coronary artery disease patients accounted for more than 50%, and the proportion of patients with chronic kidney disease accounted for more than 60%, the proportion of patients with atria fibrillation accounted for less than 30%, and the Society of Thoracic Surgeons predicted risk of mortality score was >8 points, patients with PPMI had higher long-term all-cause mortality than those without PPMI. Conclusions. Among the patients who underwent TAVR, those who developed PPMI had higher long-term all-cause mortality. [ABSTRACT FROM AUTHOR]

The monodispersed hard-sphere system is one of the simplest models for the study of phase transitions. Despite intensive studies of crystallization and melting of hard-sphere face-centered cubic (FCC) crystals, the phase transformations of hard-sphere body-centered cubic (BCC) crystals have not been explored because hard spheres cannot form a stable BCC lattice. In fact, unstable BCC hard-sphere crystals and their related phase transformations can be experimentally achieved. Here, we measured the kinetics of the melting and solid-solid transformations of BCC hard-sphere crystals at various volume fractions via molecular dynamics simulations. When the volume fraction ϕ < 0.494, the system melts catastrophically. At ϕ > 0.545, the BCC crystal transforms to a metastable polycrystal consisting of FCC and hexagonal close-packed (HCP) domains, which is different from those crystallized from supercooled liquids, and then slowly equilibrates toward the FCC crystal. At 0.494 < ϕ < 0.545, the BCC crystal transforms to an intermediate-order metastable state consisting of BCC and non-crystal particles without FCC and HCP symmetries and then equilibrates toward the coexistence of the FCC crystal and liquid. We further studied the melting and BCC-FCC transitions of crystals composed of soft spheres with potential u(r) = ϵ(r/σ)−n. The unstable BCC crystals at n = 12, 9, 8 exhibit similar melting and BCC-FCC transitions as hard-sphere BCC crystals, while the metastable BCC crystals at n = 5, 6, 7 melt quickly at low densities but take very long time for the BCC-FCC transition at high densities. We also estimate the BCC-FCC interfacial energy and critical nucleus size. These results cast light on the melting and solid-solid transformations of atomic BCC crystals, which exist widely in nature. [ABSTRACT FROM AUTHOR]

In the past decade, the architecture, engineering, and construction industry has witnessed increasing growth in the green building market and continues to expect a promising future. Although companies in the industry have played a significant role in developing the green building market, scarce studies have analyzed changes in the market from the perspectives of these corporations. Also, few studies classify green building companies by characteristics. To fill these gaps of knowledge, we explored the characteristics of the US green building market from a corporate perspective, specifically investigating green contractors and design firms. We first collected data of 464 top US green building companies identified by the Engineering News-Record over the past decade and explored the development trend of the green building market, based on the green revenue generated by these companies. We found that the general growth trend in the US green building market in the past decade could be divided into three stages: a rapid-growth stage (2000–2008), a steady-growth stage (2009–2013), and a maturity and transformation stage (2014–2016). We then categorized the 464 organizations into three groups with distinct characteristics by k -means cluster analysis techniques, including mature green building companies, sector-oriented green building companies, and primary-stage green building companies. This study provides the academic and practitioner communities with a holistic understanding of the development of the US green building market from the view of burgeoning companies. Corporate-level management systems and sustainable practices of the three clusters of green building companies also provide guidance for construction companies in the various stages of transformation towards sustainability to adopt different strategies. [ABSTRACT FROM AUTHOR]

Digital surface model (DSM) generation is one of the fundamental issues in photogrammetry and the mapping industry. This paper provides a comprehensive assessment of state‐of‐the‐art image matchers using nine open‐source and commercial software packages on aerial and unmanned aerial vehicle (UAV) images and five software packages on spaceborne images. Two datasets provide an update on DSM generation software for both airborne and spaceborne data: a 5 × 5 UAV image block with high‐precision models; and a WorldView‐1 stereopair with lidar reference data. To understand the performance of the image matchers, accuracy analysis is additionally performed on five selected ground objects. The tested image matchers adopting hierarchical semi‐global matching fitted the reference DSM better, thus yielding better accuracy. [ABSTRACT FROM AUTHOR]

In this study, hydrogen was determined in the ER5183 wires for MIG welding, and the effect of hydrogen in the wires on the tensile strength as well as the fracture behavior of Al–Mg MIG weld were investigated in order to clarify the affecting mechanism by hydrogen, which provided a reasonable range of hydrogen content in ER5183 welding wires. The results showed that, with the increasing hydrogen content, the tensile strength of the corresponding welds decreased accordingly. During the fracture process of the weld, hydrogen played serious roles as follows, accelerating the fracture process, promoting the formation of pores and causing the decohesion of the inclusion and matrix. By the mechanisms mentioned above, hydrogen changed the feature of fracture morphology from dimples to various defects. Considering the high tensile strength as well as the fine microstructure of the welds, the hydrogen content of the ER5183 welding wires should be controlled below 0.18 μg/g. • Determining the hydrogen content in the ER5183 welding wires for MIG welding. • Investigating the effect of hydrogen content on the tensile strength as well as the fracture behavior of Al–Mg MIG weld. • Finding the decohesion phenomenon, crack and porosity in the weld microstructure. • Giving a reasonable range of hydrogen content in ER5183 aluminum welding wire. [ABSTRACT FROM AUTHOR]

We studied the self-diffusion of colloidal ellipsoids in a monolayer near a flat wall by video microscopy. The image processing algorithm can track the positions and orientations of ellipsoids with subpixel resolution. The translational and rotational diffusions were measured in both the laboratory frame and the body frame along the long and short axes. The long-time and short-time diffusion coefficients of translational and rotational motions were measured as functions of the particle concentration. We observed the nondiffusive crossover region in the intermediate time regime due to the caging of neighboring particles. Both the beginning and the ending times of the intermediate regime exhibit power-law dependence on concentration. The long-time and short-time diffusion anisotropies change nonmonotonically with concentration and reach minima in the semidilute regime because the motions along long axes are caged at lower concentrations than the motions along short axes. The time derivatives of mean-square displacements change linearly with the inverse of time in the intermediate time regimes at various particle densities. This indicates that their relaxation functions decay as 1/t which provides new challenges in theory. The effects of coupling between rotational and translational Brownian motions were demonstrated and the two time scales corresponding to anisotropic particle shape and anisotropic neighboring environment were measured. [ABSTRACT FROM AUTHOR]

We recently have reported [J. Chem. Phys. 122, 164701 (2005)] a family of electroconvective patterns that arise when charge-stabilized colloidal dispersions are driven by constant (dc) vertical electric fields. Competition between gravity and electrokinetic forces acting on the individual spheres in this system leads to the formation of highly organized convective instabilities involving hundreds of spheres. Here, we report a distinct class of electroconvective patterns that emerge in confined aqueous dispersions at higher biases. These qualitatively resemble the honeycomb and labyrinthine patterns formed during thermally driven Rayleigh-Bénard convection, but arise from a distinct mechanism. Unlike the localized colloidal electroconvective patterns observed at lower biases, moreover, these system-spanning patterns form even without dispersed colloidal particles. Rather, they appear to result from an underlying electroconvective instability during electrolysis in the parallel plate geometry. This contrasts with recent theoretical results suggesting that simple electrolytes are linearly stable against electroconvection. [ABSTRACT FROM AUTHOR]

Applying an electric field to an aqueous colloidal dispersion establishes a complex interplay of forces among the highly mobile simple ions, the more highly charged but less mobile colloidal spheres, and the surrounding water. This interplay can induce a wide variety of visually striking dynamical instabilities even when the applied field is constant. This paper reports on the highly organized patterns that emerge when electrohydrodynamic forces compete with gravity in thin layers of charge-stabilized colloidal spheres subjected to low voltages between parallel-plate electrodes. Depending on the conditions, these spheres can form levitating clusters with morphologies ranging from tumbling clouds to toroidal vortex rings and to writhing labyrinths. [ABSTRACT FROM AUTHOR]

A system’s temperature can be expressed in terms of its constituents’ instantaneous positions rather than their momenta. Such configurational temperature definitions offer substantial benefits for experimental studies of soft condensed matter systems, most notably their applicability to overdamped systems whose instantaneous momenta may not be accessible. We demonstrate that the configurational temperature formalism can be derived from the classical hypervirial theorem, and introduce a hierarchy of hyperconfigurational temperature definitions, which are particularly well suited for experimental studies. We then use these analytical tools to probe the electrostatic interactions in monolayers of charge-stabilized colloidal spheres confined by parallel glass surfaces. The configurational and hyperconfigurational temperatures, together with a thermodynamic sum rule, provide previously lacking self-consistency tests for interaction measurements based on digital video microscopy, and thereby cast light on controversial reports of confinement-induced like-charge attractions. We further introduce a method to determine unknown parameters in a model potential by using consistency of the configurational and hyperconfigurational temperatures as a set of constraints. This approach, in principle, also should provide the basis for a model-free estimation of the pair potential. [ABSTRACT FROM AUTHOR]

Megaprojects carry high risks and many uncertainties, are difficult to coordinate, and involve many stakeholders. Traditional project management concepts and strategies have been proven to be less-than-efficient for modern megaprojects. To a certain extent, project governance could effectively resolve some limitations that traditional project management shows, including the clarification of responsibilities, privileges, and benefits between participating stakeholders. This study contributes to the development of a comprehensive conceptual governance model, specifically for megaprojects, that quantifies governance status over the period of megaproject development and delivery. A megaproject case study in China was used to demonstrate the way this model could facilitate a dynamic governance research approach. We also found project governance status and project performance to be positively correlated. Adjusting governance strategies properly and in a timely manner could help improve the overall project development, and as a result, lead to successful project delivery. [ABSTRACT FROM AUTHOR]

This work focused on the influence of hydrogen content on the microstructure and mechanical properties of ER5183 Al-Mg-Mn alloy wires for aluminum alloy welding. The hydrogen content of the ER5183 wires was measured, the macroscopic and microscopic morphologies of fractures were observed as well as the microstructure of the wires, and the tensile strength of the wires was also tested and investigated. The experimental results demonstrated three typical irregular macroscopic fractures of the wires appeared during the drawing process when the hydrogen content exceeded 0.23 μg/g. In the meantime, the aggregated pores were observed in the microstructure of the ϕ5.2 mm wire with the hydrogen content of 0.38 μg/g. Such defects may become the origin of cracks in subsequent processing and tensile tests. Moreover, higher hydrogen content in the ϕ5.2 mm welding wire will bring obvious changes in the fracture surface, which are internal cracks and micropores replacing the original uniform and compact dimples. With the higher hydrogen content, the tensile strength and plastic strain rate of ϕ1.2 mm wires would decrease. At the same time, unstable crack propagation would occur during the process of plastic deformation, leading to fracture. Considering the mechanical properties and microstructure, the hydrogen content of the ER5183 wires should be controlled below 0.23 μg/g. [ABSTRACT FROM AUTHOR]

Green buildings have gained increasing momentum during the past decade, evidenced by an uptick in green building construction worldwide. To facilitate green building development, it is crucial to understand the current geographical distribution of green buildings, thereby identifying emerging markets and opportunities for future growth. However, very few studies investigated the spatial characteristics of the green building market and the factors influencing the distribution of green buildings. By examining the national green building market in the United States, we studied the spatial distribution patterns and significant influencing factors of the county-level US green building markets. Cluster mapping and hot spots of the green building markets were identified through spatial autocorrelation analysis. A spatial regression model with high performance (R2 of 0.83) was developed to identify the significant influencing factors. We found a statistically significant clustering phenomenon of county-level US green building markets. The spatial error model reveals that three factors, namely, the number of housing units, gross domestic product, and the local green building company index, significantly influence the number of green buildings at the county level. We also found that the county-level green building market is influenced by these factors of not only the host county, but also the neighboring counties. Our findings provide a useful reference for stakeholders' decision-making process concerning local green building market development. [ABSTRACT FROM AUTHOR]

The built environment contributes significantly to rapidly growing world energy expenditure and tighter spatial interrelationships can exacerbate this effect in cities. The concept of the Inter-Building Effect (IBE) was introduced to understand the complex mutual impact within spatially proximal buildings. Our research sought to develop a systematic approach to disaggregate and quantify the influence of mutual shading and mutual reflection within a network of buildings. We built an urban building network model and conducted cross-regional simulations under different climatological contexts by examining mutual shading only and mutual reflection only, respectively. We then expanded our investigation by examining two realistic urban contexts in Perugia, Italy. We found the shading effect played a more significant role in terms of impact on energy consumption. The results of the simulations in varying climatological contexts also revealed consistent trends of greater impact on the IBE for shading and reflection in warmer climatic cities. These findings expand and deepen our understanding of inter-building effects and may help in the search to minimize mutual influences between buildings that lead to increases in energy consumption in urban environments. [ABSTRACT FROM AUTHOR]

Microcarriers with a large surface area have attracted much attention in the field of large-scale cell culture. The preparation of microcarriers is mainly based on methods such as emulsification, suspension polymerization, solvent evaporation, organic phase separation (cohesion) and spray drying. Many of these require the use of organic solvents. In general, organic solvents are considered to be toxic and not conducive to environmental protection. In this study, zein microcarriers were successfully prepared via a novel method in which only glycerol was used as the dispersing medium. The size of these microcarriers was controllable, and the preparation process was simple to perform. Vero cells, commonly used in the production of vaccines, were cultured on the surface of the zein microcarriers to evaluate the microcarriers' performance in cell culture. The cells could attach and spread on the surface, without any difference compared with cells on the surface of Cytodex 1. The cell density reached its maximum on the fourth day, which was approximately 10 times the initial density. This is the first report that zein can be used as a microcarrier for the mass production of a large-scale suspension cell culture, which shows the potential of zein as a replacement for commercial non-degradable materials. [ABSTRACT FROM AUTHOR]

More than one-third of energy expenditure is attributable to buildings. Urbanization is leading to tighter spatial interrelationships among buildings, which is escalating building energy consumption due to the impact of buildings on one another. This, in turn, is exacerbating Urban Heat Island (UHI) effects. We sought a bio-inspired solution to this significant engineering issue and discovered a similar heat island effect in flowers, namely the “micro-greenhouse effect.” However, a special cooling effect has been observed in a temperate flower— Galanthus nivalis —which generates cooler intrafloral temperatures. In this paper, we studied the special retro-reflecting property of the flower petals, which has been suggested as a possible contributor to this cooling effect, and modeled a bio-inspired retro-reflective building envelope. We conducted cross-regional energy simulation of building networks in order to examine its thermal-energy impact. We found that building surface temperatures dropped considerably when neighboring buildings were retrofitted with a bio-inspired retro-reflective façade. We concluded that a bio-inspired retro-reflective building envelope can; (1) lessen the reflected heat of solar radiation in spatially proximal buildings leading to reduced UHI, and (2) reduce the energy required for cooling. These findings have broad implications for building design, urban planning, development of retro-reflective technology, and environmental conservation. [ABSTRACT FROM AUTHOR]

Traditional models that employ CNNs as encoders do not sufficiently combine high-level features and low-level features. However, high-level features are rich in semantic information but lack spatial detail, while low-level features are the opposite. Therefore, the integrated utilization of multi-level features and the bridging of the gap between them is crucial to promote the accuracy of semantic segmentation. To address this issue, we presented communicating mutual attention (CMA) and communicating self-attention (CSA) modules to enhance the interaction and fusion of different levels of feature maps. On the one hand, CMA aggregates the global context information of high-level features into low-level features and embeds the spatial detail localization characteristics of low-level features in high-level features. On the other hand, the CSA module is deployed to integrate the spatially detailed representation of low-level features into the attention map of high-level features. We have experimented with the communicating attention network (CANet), a U-net-like network composed of multiple CMA and CSA modules, on the ISPRS Vaihingen and Potsdam datasets with mean F1-scores of 89.61% and 92.60%, respectively. The results demonstrate that CANet embodies superior performance in the semantic segmentation task of remote sensing of images. [ABSTRACT FROM AUTHOR]

Public-private partnerships (PPPs) have become an important option for financing urban rail transit (URT) projects. To ensure the effective operation of URT projects and better serve the public, governments must select suitable operators as part of private-sector consortiums to achieve successful PPP implementations, but they often face a dilemma in choosing between local URT groups and nonlocal operators. In this study, we examine the key factors that determine governments' operator choices for URT PPP (URT3P) projects with a two-stage approach. A four-dimensional (4D) indicator system containing 20 factors was first developed, and least absolute shrinkage and selection operator (LASSO) regression was applied to analyze one of the largest regional URT data sets in China. Five key factors that significantly influence operator selection are identified, including project operation duration, government-business relationships, private-sector entity organization type, private-sector entity ownership type, and whether the private-sector entity owns an operating firm. This study contributes to the body of knowledge on URT3P project management, and this systematic approach can be used by local governments to select suitable operating partners in similar exploratory contexts. [ABSTRACT FROM AUTHOR]

Geometric frustration arises when lattice structure prevents simultaneous minimization of local interaction energies. It leads to highly degenerate ground states and, subsequently, to complex phases of matter, such as water ice, spin ice, and frustrated magnetic materials. Here we report a simple geometrically frustrated system composed of closely packed colloidal spheres confined between parallel walls. Diameter-tunable microgel spheres are self-assembled into a buckled triangular lattice with either up or down displacements, analogous to an antiferromagnetic Ising model on a triangular lattice. Experiment and theory reveal single-particle dynamics governed by in-plane lattice distortions that partially relieve frustration and produce ground states with zigzagging stripes and subextensive entropy, rather than the more random configurations and extensive entropy of the antiferromagnetic Ising model. This tunable soft-matter system provides a means to directly visualize the dynamics of frustration, thermal excitations and defects. [ABSTRACT FROM AUTHOR]

Transportation public–private partnership (PPP) projects are long-term projects that usually break the status quo of public ownership. In fact, opposition to PPP projects stems from a variety of factors, such as political influence to favor certain interest groups and high toll prices. Close examination reveals that vulnerability to societal and political domains originates at certain individual points and creates a complex web of problems as it propagates through different socioeconomic and political levels and project stages. This article attempts to unveil such complex and problematic trends by analyzing ten failed transportation PPP projects to identify critical socioeconomic and political failure factors. Employing questionnaire surveys and path analysis, a failure-mechanism model is developed to depict all possible transportation PPP project vulnerabilities to the socioeconomic and political domains. This article's failure-mechanism model could act as a vulnerability-prediction model for transportation PPP practitioners in the public and private sectors, and it can help better understand socioeconomic and political issues’ impacts to transportation PPP projects. [ABSTRACT FROM AUTHOR]

With increasing attention on sustainable development, 3D printing construction and recycled concrete have drawn extensive interest as emerging construction technology and novel building materials. At this intersection, we attempted to evaluate the environmental impact and economic benefit of 3D printed buildings made of recycled concrete employing life-cycle assessment tools. Goal and scope definition, materials and scenarios, life-cycle inventory analysis, life-cycle assessment impact, and interpretation were detailed based on the characteristics of concrete 3D printing to better quantify the sustainability potential of recycled concrete used in 3D printed buildings. We found that although increases in using recycled aggregate could produce less pollutant emissions, the environmental impact caused by 3D printing concrete construction is generally larger than traditional cast-in-situ concrete construction. This is because additional cement is required in the 3D printing process to maintain dependable concrete performance. From the economic perspective, 3D printing concrete construction technology has significant advantages over traditional cast-in-situ concrete construction, saving the heavy cost of formwork and labor. Such benefit is even more pronounced in geometrically irregular buildings. We also found that the cost of buildings made of recycled concrete decreased as the proportion of recycled aggregate increased, owing to the higher price of natural aggregate. This paper contributes to identifying key factors in the life-cycle evaluation of 3D printing construction with cementitious materials. • The sustainability potential of recycled concrete used in 3D printed buildings is evaluated. • 3D printed concrete buildings generate higher environmental impact because of additional cement content. • 3D printed concrete buildings have significant economic advantages, especially for those geometrically irregular buildings. [ABSTRACT FROM AUTHOR]

Traditional stereo dense image matching (DIM) methods normally predefine a fixed window to compute matching cost, while their performances are limited by the matching window sizes. A large matching window usually achieves robust matching results in weak-textured regions, while it may cause over-smoothness problems in disparity jumps and fine structures. A small window can recover sharp boundaries and fine structures, while it contains high matching uncertainties in weak-textured regions. To address the issue above, we respectively compute matching results with different matching window sizes and then proposes an adaptive fusion method of these matching results so that a better matching result can be generated. The core algorithm designs a Convolutional Neural Network (CNN) to predict the probabilities of large and small windows for each pixel and then refines these probabilities by imposing a global energy function. A compromised solution of the global energy function is utilized by breaking the optimization into sub-optimizations of each pixel in one-dimensional (1D) paths. Finally, the matching results of large and small windows are fused by taking the refined probabilities as weights for more accurate matching. We test our method on aerial image datasets, satellite image datasets, and Middlebury benchmark with different matching cost metrics. Experiments show that our proposed adaptive fusion of multiple-window matching results method has a good transferability across different datasets and outperforms the small windows, the median windows, the large windows, and some state-of-the-art matching window selection methods. [ABSTRACT FROM AUTHOR]

As a light-weighting structural material, aluminum alloy is being applied in the automobile and high-speed train, the property of which however is affected by the content of hydrogen, and much importance has been attached to the impact property of aluminum alloy. In this study, hydrogen was determined in ER5183 welding wire and afterwards the effect of hydrogen content on the impact property of Al–Mg MIG weld is investigated to clarify the mechanism of hydrogen action which provided a reasonable control range of hydrogen content in aluminum welding wire. The results show that the impact toughness of the weld is decreased with the increasing hydrogen content. In addition, the decohesion of impurities from the matrix and the formation of porosity are also observed in the weld. The morphology of impact fracture appears facet and porosity due to the "hydrogen-enhanced localized plasticity" effect on plasticity. Considering the good impact property as well as the fine microstructure of the weld, hydrogen content of the ER5183 welding wires should be controlled below 0.18 μg/g. • Introducing hydrogen by using ER5183 welding wires into Al–Mg weld. • Studying the effect of hydrogen embrittlement on impact properties of Al–Mg weld. • Investigating the influence of hydrogen on morphology of impact fracture of Al–Mg weld. • Describing the hydrogen-induced dislocation motion and multiplication phenomenon. • Giving a reasonable range of hydrogen content in ER5183 aluminum welding wire. [ABSTRACT FROM AUTHOR]

Previously we have reported a family of convective patterns formed by charge-stabilized aqueous colloidal suspensions under constant (dc) vertical electric fields [Y. Han and D. G. Grier, J. Chem. Phys. 122, 164701 (2005); and ibid. 125, 144707 (2006)]. These patterns form in the bulk when electrokinetic forces act in the opposite direction to gravity. Here, we report on cellular patterns that silica colloidal spheres form on a horizontal electrode when electrokinetic forces act in the same direction as gravity. We suggest that these cellular patterns form as a result of bulk electroconvection mediated by charge injection into the supporting aqueous electrolyte. This charge-injection mechanism also accounts for some aspects of electroconvective pattern formation in our earlier reports. Cellular patterns reorganize themselves into distinct transient patterns after the driving voltage is turned off. These transients cast new light on the complex interplay between the motions of charged colloidal spheres and the ionic relaxation of water undergoing electrolysis. [ABSTRACT FROM AUTHOR]

Sustainable development has become one of the major objectives in building and operating healthcare facilities, as they exert a major impact on the environment and society. It is also critically important for modern healthcare facilities to adapt to an aging population, rapid technology upgrades, and the increasing demand for quality health care. In this background, sustainable healthcare facilities (SHFs) have attracted growing attention from researchers in the past decade. However, there has not been a clear scope of SHFs, which undermines the theoretical foundation of SHFs evaluation. This study identifies, aggregates, and analyzes the existing body of knowledge to address such issue. We attempted to reveal the dimensions of sustainability in the context of healthcare facilities, the links among the dimensions of sustainability, and the framework of SHFs themes based on a systematic scoping review. A four-dimensional model of sustainability was discussed and a framework of SHFs themes is proposed, consisting of core business, supporting service, and organizational environment layers. We suggest future research to focus more on the core business and organizational environment layers and the links among the different attributes of sustainability in the SHFs field. [ABSTRACT FROM AUTHOR]

Rapid urbanization is a major trend in global population migration. There is growing debate about whether this urban-rural disparity exacerbate depression at the individual level. This study aims to investigate how urban living has a beneficial impact on individual mental health. Based on the data of 15,764 participants in the 2018 China Health and Retirement Longitudinal Study (CHARLS), we perform analysis of variance to identify the gap in depression levels between urban and rural areas. Extensive comparisons and detailed statistical analyses are carried out to demonstrate the differences in social participation between urban and rural residents. Finally, we conduct a series of mediation and moderation analyses to reveal the underlying mechanisms of depressive disorder benefits of cities. The results indicate that those who lived in urban areas were less likely to suffer from depression (β = −1.461, 95 % CI = [−1.691, −1.235], p < 0.001). Social engagement is found to mediate the relationship between residence type (β = 0.164, 95 % CI = [0.136, 0.193], p < 0.001) and individual depression (β = −0.462, 95 % CI = [−0.587, −0.337], p < 0.001). City size plays a moderating role in the association between urban living and social engagement. The mechanism is conducted through cross-sectional data. Self-reported depression status is accessed in this study, which could lead to measurement error. This study demonstrates the beneficial effects of urban living on individual depression, and reveals the mechanism by which urbanization at different scales affects the prevalence of depression. • This study fueled the debate about depressive disorder from growing cities with a nationwide empirical analysis. • We identified the underlying mechanism by which urban living could protect residents from the obnoxious depression. • Our observation also revealed the contingency of the protective effect of cities against depression. [ABSTRACT FROM AUTHOR]

We studied the melting behavior of two-dimensional colloidal crystals with a Yukawa pair potential by Brownian dynamics simulations. The melting follows the Kosterlitz-Thouless-Halperin-Nelson-Young (KTHNY) scenario with two continuous phase transitions and a middle hexatic phase. The two phase-transition points were accurately identified from the divergence of the translational and orientational susceptibilities. Configurational temperatures were employed to monitor the equilibrium of the overdamped system and the strongest temperature fluctuation was observed in the hexatic phase. The inherent structure obtained by rapid quenching exhibits three different behaviors in the solid, hexatic, and liquid phases. The measured core energy of the free dislocations, Ec = 7.81 ± 0.91 kBT, is larger than the critical value of 2.84 kBT, which consistently supports the KTHNY melting scenario. [ABSTRACT FROM AUTHOR]

The digital revolution has swept the world, but the construction industry, the backbone of the global economy, has lagged. Government policy is expected to promote the development of digital technologies centered around building information modeling (BIM) in the construction industry. However, how digital technology–related policies diffuse within a country and influence innovation regionally remains unknown. Using 2011–2019 panel data from 31 provinces in mainland China, we found that BIM policy diffuses not only vertically among national and regional governments, but also horizontally among neighboring regional governments, both of which accelerate the adoption of BIM policy in various regions across the country. We also found that there is a causal relationship between regional BIM policies and related BIM innovation. Further, the positive influence of policies on innovation is more significant in regions with low economic development and high openness levels. This study not only contributes to understanding the impact of policy diffusion on BIM innovation, but also offers insights into the research on policies and innovation of digital technology in the construction industry from a macro perspective. The empirical evidence provides a practical reference for policymakers to accelerate the adoption of digital technology policy within the country and promote technological innovation. [ABSTRACT FROM AUTHOR]

Weak ties are becoming mainstream in daily relationships and play an essential role in the improvement of individuals' mental health. Despite growing concerns on depression, inclusion of weak ties is limited. To address the gap, this study empirically shed light on the role of weak ties on individual depression in the context of economic development. A cross-sectional study was conducted based on 2018 China Health and Retirement Longitudinal Study (CHARLS) with a sample of 16,545 individuals. A moderated mediation model is constructed to evaluate the impact of economic development (GDP) on the degrees of depression, the mediating effect of weak ties, and the moderating effect of residents' residence types (living in urban or rural areas). Economic development exerts a significant direct impact on depression (β = − 1.027 , p <0.001). Weak ties are significantly negatively correlated with depression (β = − 0.574 , p <0.001), and act as a mediator between economic development and local individual depression. In addition, the residence type plays a moderating role between economic development and weak ties (β = 0.193 , p <0.001). That is, living in urban areas would introduce the higher the level of weak ties. Higher economic development is largely conducive to alleviating the degrees of depression, weak ties play a mediating role between economic development and depression, and residence types exert a positive moderating effect on the economic development and weak ties. • This study empirically shed light on the role of weak ties on individual depression based on 2018 CHARLS. • Economic development could significantly affect degrees of individual depression through the mediating effect of weak ties. • Residence types play a moderating role between economic development and weak ties. [ABSTRACT FROM AUTHOR]

Abstract Piezoelectric materials are capable of transforming mechanical strain and vibration energy into electrical energy. This property allows opportunities for implementing renewable and sustainable energy through power harvesting and self-sustained smart sensing in buildings. As the most common construction material, plain cement paste lacks satisfactory piezoelectricity and is not efficient at harvesting the electrical energy from the ambient vibrations of a building system. In recent years, many techniques have been proposed and applied to improve the piezoelectric capacity of cement-based composite, namely admixture incorporation (e.g. lead zirconate titanate, barium zirconate titanate, carbon particles, and steel fibers) and physical treatments (e.g. thermal heating and electrical field application). The successful application of piezoelectric materials for sustainable building development not only relies on understanding the mechanism of the piezoelectric properties of various building components, but also the latest developments and implementations in the building industry. Therefore, this review systematically illustrates research efforts to develop new construction materials with high piezoelectricity and energy storage capacity. In addition, this article discusses the latest techniques for utilizing the piezoelectric materials in energy harvesters, sensors, and actuators for various building systems. With advanced methods for improving the cementitious piezoelectricity and applying the material piezoelectricity for different building functions, more renewable and sustainable building systems are anticipated. [ABSTRACT FROM AUTHOR]

Previous studies have used complex network theory to examine the characteristics of China's High-Speed Rail (HSR). Nevertheless, little attention is paid to China's HSR network's dynamic evolution and the coevolution of node attributes and embedded structural characteristics. Our study builds China's HSR network using a complex network approach and spatial analysis technique to address this issue. Additionally, we employ a stochastic actor-oriented model (SAOM) to properly decompose the three types of effects on the generation of China's HSR network (i.e., network structure, attribute-based similarity, and exogenous control variables). This study discusses the underlying hypotheses and indicates that 3-cycles is a critical structural factor for the formation of China's HSR network. In terms of the effects of attribute-based similarity, cities with similar Gross Domestic Product (GDP) and geographical proximity are essential nodal drivers for the evolution of the HSR network. Notably, the administrative rank of cities exhibits a significantly negative driving force and a alter effect. These findings shed light on the interactive process of urban regional development and the dynamic evolution of the HSR network, assisting the central and local governments in enacting and implementing appropriate HSR planning policies, ultimately achieving effective urban planning and management. • The 3-cycles has a positive effect on the formation of the HSR network. • Similar GDP and geographical proximity of cities are critical drivers for the HSR. • Urban rank exhibits a significantly negative driving force and a alter effect. [ABSTRACT FROM AUTHOR]

Crystal melting is affected by many factors such as defects, surfaces, dimensionality, lattice structure, and particle interaction, and thus exhibits rich phenomenology. It is usually a first-order phase transition which currently lacks a fundamental theory. Despite numerous studies over the past century, melting remains poorly understood at the microscopic level. Micrometer-sized colloidal particles can be viewed as 'big atoms' which can assemble into various phases. Their thermal motions can be directly imaged and tracked using optical microscopy. Hence, colloids are powerful model systems for studying phase transitions. Recent progress made in fabricating tunable micrometer-sized colloidal particles has enabled the direct visualization of crystal melting with single-particle dynamics. The observations have greatly expanded our understanding of melting kinetics. In this review, the experiments and simulations conducted on the superheating, melting, and premelting of colloidal crystals have been surveyed. The latest results on crystal melting obtained from colloidal model systems and challenges and future perspectives have been discussed. [ABSTRACT FROM AUTHOR]

In this paper, four widely used temporal compositing algorithms, i.e. median, maximum NDVI, medoid, and weighted scoring-based algorithms, were evaluated for annual land cover classification using monthly Landsat time series data. Four study areas located in California, Texas, Kansas, and Minnesota, USA were selected for image compositing and land cover classification. Results indicated that images composited using weighted scoring-based algorithms have the best spatial fidelity compared to other three algorithms. In addition, the weighted scoring-based algorithms have superior classification accuracy, followed by median, maximum NDVI, and medoid in descending order. However, the median algorithm has a significant advantage in computational efficiency which was ∼70 times that of weighted scoring-based algorithms, and with overall classification accuracy just slightly lower (∼0.13% on average) than weighted scoring-based algorithms. Therefore, we recommended the weighted scoring-based compositing algorithms for small area land cover mapping, and median compositing algorithm for the land cover mapping of large area considering the balance between computational complexity and classification accuracy. The findings of this study provide insights into the performance difference between various compositing algorithms, and have potential uses for the selection of pixel-based image compositing technique adopted for land cover mapping based on Landsat time series data. [ABSTRACT FROM AUTHOR]

The strength of polycrystal increases as the grain diameter l decreases, i.e. the Hall–Petch behaviour. This trend reverses at about 3 < l < 15 nm, i.e. the inverse-Hall–Petch behaviour. How the grain size affects material's strength at l < 3 nm (~12 particles) remains unclear. Here our simulations use mixtures of soft and hard particles so that compression can continuously reduce l to merely a few particles, resulting in ultrafine-grained solids termed as glass-crystal composites. Beyond the conventional Hall–Petch strengthening and inverse-Hall–Petch softening, we observe a power-law strengthening at l < 14 particles as a result of the blockage of shear-banding by crystalline grains. Amorphous and crystalline regions accommodate shear strains via bond-breaking and collective rotation, respectively. Moreover, a polycrystal–glass transition occurs at l = 14 particles featured with peaks of various quantities, which deepens the understanding on softening–strengthening transition. Hall-Petch behaviour dictates that with a reduction in grain size the strength of a polycrystalline material increases. Here, the authors model glass-crystal composites of soft and hard particles uncovering a power-law strengthening behaviour beyond the Hall-Petch and inverse-Hall-Petch regimes when grain size is reduced to below 3 nm. [ABSTRACT FROM AUTHOR]

Feature matching between high-resolution satellite stereos plays an important role in satellite image orientation. However, images of changed regions, weak-textured regions and occluded regions may generate low-quality matches or even mismatches. Furthermore, matching throughout the entire satellite images often has extremely high time cost. To compute good matching results at low time cost, this paper proposes an image block selection method for high-resolution satellite stereos, which processes feature matching in several optimal blocks instead of the entire images. The core of the method is to formulate the block selection into the optimization of an energy function, and a greedy strategy is designed to compute an approximate solution. The experimental comparisons on various satellite stereos show that the proposed method could achieve similar matching accuracy and much lower time cost when compared with some state-of-the-art satellite image matching methods. Thus, the proposed method is a good compromise between matching accuracy and matching time, which has great potential in large-scale satellite applications. [ABSTRACT FROM AUTHOR]

The relationship patterns of organizations participating in disaster response projects have a significant impact on their performance. However, research on appropriate relationship patterns of disaster response organizations is lacking both in theory and practice. To fill this gap, we conducted a comparative study on three interorganizational relationship patterns: government-centric, decentralized participatory, and partially collaborative. Drawing on the complex network modeling method, the mechanism of the interorganizational network composed of participating organizations in disaster response projects are conceptualized to depict different relationship patterns. Then, we conducted numerical simulation to further explore the optimal relationship pattern from the perspective of disaster response project effectiveness, efficiency, and fairness. The results reveal that the optimal organizational relationship pattern varies with changes in disaster response conditions. In the initial situation of an emergency with insufficient resources, government agencies should coordinate nongovernmental organizations (NGOs) to participate in disaster response in an orderly manner. When the demand for emergency resources drops, or the supply of emergency resources gradually becomes sufficient as disaster response projects progress, the government-centric pattern becomes the optimal relationship pattern. Moreover, the relationship between the response network structure and disaster response performance turns out to be inconsistent. At the early stage, response performance can be improved by reducing the number of steps to complete disaster relief and by appropriately increasing the connections between government agencies and NGOs. When a disaster situation is mitigated, the centralization of response power and unified coordination should be emphasized to improve emergency response performance. This study contributes to improving disaster response performance from the organizational relationship perspective and enriching disaster management theories. [ABSTRACT FROM AUTHOR]

The importance of reliability in conducting empirical research has been emphasized by construction engineering and management (CEM) scholars. Survey data commonly are used in empirical CEM studies. However, the use of such data in empirical analysis is susceptible to common method bias (CMB) issues, which can generate false correlations between dependent and explanatory variables, leading to spurious and unreliable results. To facilitate recent discussion about the rigorous application of research methodologies in CEM research, we provide a comprehensive overview of major CMB sources and examine articles published in the last 5 years to identify potential CMB issues in the Journal of Construction Engineering and Management. We found that approximately 90% of articles that used survey data in the empirical analysis were likely to be affected by CMB. The major source is the common rater effect, followed by the item characteristics effect and the measurement context effect. Because only a handful of studies tested or controlled for CMB, we propose effective and targeted ex ante procedural controls and ex post statistical controls to mitigate its negative impact. This study sheds light on an important and pervasive methodological issue in empirical CEM studies, and provides guidelines for improving the reliability of future empirical research in the CEM field. [ABSTRACT FROM AUTHOR]

Public–private partnerships (PPPs) have been accused of importing practices and norms from the private sector that could conflict with core public values (e.g., accountability, transparency, responsiveness, responsibility, and quality). Some scholars believe that PPP renegotiations can enhance public values through ex post adaptation, interference, and monitoring, while others emphasize that PPP renegotiations incentivize opportunistic behaviors on the part of governments and other stakeholders. Focusing on China's PPPs, this study investigates how the renegotiation of PPP projects impacts public values in infrastructure service delivery through a Delphi survey. Two rounds of Delphi survey questionnaires were conducted with 14 PPP experts in China. The result shows that, in general, renegotiations can safeguard or even strengthen public values in PPPs, although sometimes at the expense of managerial values. Government-led renegotiations are more likely to increase public values than contractor-led renegotiations. This study contributes to the extant literature on PPPs by shifting research concerns from managerial values to public values, and from ex ante planning to ex post renegotiation. Practitioners can derive benefits from renegotiations by paying attention to their positive impact on public values. [ABSTRACT FROM AUTHOR]

Megaproject management has continuously faced new challenges that require new theories and methods. The network perspective has been an increasing trend in this context. However, there is a lack of consensus concerning the applicability of network thinking to megaprojects and the status of network analytic methods with respect to the facilitation of megaproject management. This paper aims to present the full status of the network perspective in the context of megaproject management, integrate network thinking, clarify the application of network analytic methods, and accelerate the network paradigm in the context of megaproject management. This research included a systematic review using the Preferred Reporting Items for Systematic Review and Meta-Analyses framework. A total of 152 relevant studies were retrieved from three major databases and reviewed. The findings of this study were based on a novel integrated framework that included the constitutive and the analytic perspectives of the network paradigm. The constitutive perspective sheds light on the megaproject network, its definition, characteristics pertaining to network thinking, and megaproject governance through network logic. The analytic perspective illuminates the applicability of network methods to megaproject issues in detailed subknowledge areas, including stakeholder management, risk management, communication, coordination and collaboration, knowledge management, and interface management. Furthermore, these two perspectives were generalized and converged into pure categories of network research, including network mechanisms and antecedents, network patterns and dynamics, network functions and outcomes, and network controls and optimization. Based on meticulous discussions concerning the integrated framework, limitations and future directions for progress in this area were proposed to facilitate a deeper exchange of ideas in the context of any future research efforts. [ABSTRACT FROM AUTHOR]

Construction projects are cost-intensive, complex, and challenging ventures that often place employees in a harsh work environment filled with safety hazards. Employees facing such rigid characteristics must also adhere to strict time schedules to complete construction tasks; as a result, construction employees experience high stress that can deplete their psychological resources. Consequently, construction employees develop intentions to quit the organization, commonly known as turnover intentions. This study evaluates the role of ethical leadership in reducing employee turnover intentions in the construction industry. In this study, work exhaustion and psychological contract breach are considered prime antecedents of employee turnover in the construction industry. We collected data from satellite town development projects in Pakistan and performed regression path analysis to assess hypothesized relationships between construction employee turnover intention and its antecedents. The moderating effects of ethical leadership in reducing the impacts of work exhaustion and psychological contract breach were studied. Results revealed that work exhaustion and perceived psychological contract breach positively correlate with construction employee turnover intention; however, ethical leadership significantly reduced the impacts of work exhaustion and psychological contract breach on employee turnover intention. The findings and practical implications of this study can be used to help construction managers act ethically in their managerial duties to retain employees and continue to motivate employees to complete project tasks. [ABSTRACT FROM AUTHOR]

Benchmarking the energy efficiency of buildings is important for optimizing the efficient use of energy and reducing carbon footprint. Healthcare facilities have especially high energy usage, but the historical difficulty of collecting energy data from a relatively large number of healthcare facilities has made it challenging to develop the appropriate benchmarking system. In this paper, we seek to foster the task of benchmarking the energy efficiency of healthcare facilities using three different methods: multiple linear regression (MLR), generalized additive model (GAM), and energy performance index (EPI). The analysis was applied using a unique dataset that contained information on energy consumption and various building features for 22 large-size public hospitals managed by the Shanghai hospital development center (SHDC). Findings suggest that different benchmarking methods yield substantially different energy performance ranking results. Furthermore, a comparative analysis of the three benchmarking methods was conducted in terms of goodness-of-fit, consistency, and robustness. The results show that MLR tends to be the most consistent and robust benchmarking model, while GAM appears to have the best goodness-of-fit. The proposed methodology can assist hospital managers identify potential improvements for more efficient use of energy in healthcare facilities. [ABSTRACT FROM AUTHOR]

Melting is one of the most studied phase transitions important for atomic, molecular, colloidal, and protein systems. However, there is currently no microscopic experimentally accessible criteria that can be used to reliably track a system evolution across the transition, while providing insights into melting nucleation and melting front evolution. To address this, we developed a theoretical mean-field framework with the normalised mean-square displacement between particles in neighbouring Voronoi cells serving as the local order parameter, measurable experimentally. We tested the framework in a number of colloidal and in silico particle-resolved experiments against systems with significantly different (Brownian and Newtonian) dynamic regimes and found that it provides excellent description of system evolution across melting point. This new approach suggests a broad scope for application in diverse areas of science from materials through to biology and beyond. Consequently, the results of this work provide a new guidance for nucleation theory of melting and are of broad interest in condensed matter, chemical physics, physical chemistry, materials science, and soft matter. [ABSTRACT FROM AUTHOR]

Granular particles exhibit rich collective behaviors on vibration beds, but the motion of an isolated particle is not well understood even for uniform particles with a simple shape such as disks or spheres. Here we measured the motion of a single disk confined to a quasi-two-dimensional horizontal box on a vertically vibrating stage. The translational displacements obey compressed exponential distributions whose exponent β increases with the frequency, while the rotational displacements exhibit unimodal distributions at low frequencies and bimodal distributions at high frequencies. During short time intervals, the translational displacements are subdiffusive and negatively correlated, while the rotational displacements are superdiffusive and positively correlated. After prolonged periods, the rotational displacements become diffusive and their correlations decay to zero. Both the rotational and the translational displacements exhibit white noise at low frequencies, and blue noise for translational motions and Brownian noise for rotational motions at high frequencies. The translational kinetic energy obeys Boltzmann distribution while the rotational kinetic energy deviates from it. Most energy is distributed in translational motions at low frequencies and in rotational motions at high frequencies, which violates the equipartition theorem. Translational and rotational motions are not correlated. These experimental results show that the random diffusion of such driven particles is distinct from thermal motion in both the translational and rotational degrees of freedom, which poses new challenges to theory. The results cast new light on the motion of individual particles and the collective motion of driven granular particles. [ABSTRACT FROM AUTHOR]

Developing new types of transportation is considered a key solution to meet the extreme demands placed on traditional transportation infrastructure due to the increasing flow of production factors for national urban growth, especially in emerging economies. Both city transportation networks and city economic networks reflect intercity relationships in urban systems from different aspects. Although HSR networks are being developed rapidly worldwide, we still lack a deep understanding on how HSR relates to the economic growth of urban agglomerations from a "double-network" perspective. In this research, we first built city HSR networks and city economic networks, respectively, before the QAP method was used to examine their relationship during 2010–2015. By analyzing comparatively the differences of the coupling relationship in various areas in China as a typical case, this study contributes to the understanding of the dynamic coupling relationship between new forms of transportation and regional economic development. We found a strong coupling relationship between HSR and economic growth, and HSR tends to play a more prominent role in promoting urban integration and development in areas with more developed economies (coefficients of more developed areas are all above 0.6, while that of less developed areas are below 0.4). Such correlated relationship is more obvious in smaller administrative scopes compared to cross-administrative regions. This study proposed a research framework for "double-network" analysis in exploring the relationship between the different networks. It could also provide policy implantation for balanced regional development in emerging economies. • A new approach is provided to study the relationship between city transportation and economy system. • Network comparative analysis of city high-speed rail network and city economic network in China • Urban spatial patterns highly correlate with regional economic structure. • A significant positive coupling relationship exists between high-speed rail and economic growth. • Positive relationship between new form of transportation and economic growth is more obvious in developed areas. [ABSTRACT FROM AUTHOR]

Since the financial crisis in 2008, the international construction market has shown a relatively weak state of development. Along with China's "Belt and Road Initiative," an increasing number of Chinese construction firms have swarmed to explore the global market and expect to improve their financial performance via internationalization. However, few studies have addressed how and to what extent the internationalization strategy contributes to financial performance. This paper therefore proposes three sets of assumptions on this issue and establishes four regression models. Through multiple regression analysis of 32 Chinese construction firms listed in the Engineering News-Record (ENR) during the 2010–2017 period, the study described here explored the relationship between a construction firm's degree of internationalization and its financial performance as well as the moderating effect of business diversification and three types of macroenvironmental risk. The results reveal that (1) there is a U -shaped relationship between degree of internationalization of construction firms and their financial performance—when the degree of internationalization is less than 52%, the relationship is negative and when it is greater than 52%, the relationship is positive; (2) business diversification acts as a positive moderator in the relationship between internationalization and financial performance; and (3) both economic risks and social risks play a positive moderating role in the relationship between internationalization and financial performance, whereas financial risks play a negative moderating role. This study contributes to the engineering management literature not only by broadening understanding of how internationalization strategy influences financial performance but also by guiding business layout and risk management during the internationalization process. The findings of this study are limited to the sample data from a single country (i.e., China). Similar research might be conducted in the future using sample data from different countries for comparative analysis to draw more generalizable and meaningful conclusions. [ABSTRACT FROM AUTHOR]

We studied the two-dimensional freezing transitions in monolayers of microgel colloidal spheres with short-ranged repulsions in video-microscopy experiments, and monolayers of hard disks, and Yukawa particles in simulations. These systems share two common features at the freezing points: (1) the bimodal distribution profile of the local orientational order parameter; (2) the two-body excess entropy, s2, reaches -4.5±0.5 kB. Both features are robust and sensitive to the freezing points, so that they can potentially serve as empirical freezing criteria in two dimensions. Compared with the conventional freezing criteria, the first feature has no finite-size ambiguities and can be resolved adequately with much less statistics; and the second feature can be directly measured in macroscopic experiments without the need for microscopic information. [ABSTRACT FROM AUTHOR]

Video microscopy was employed to explore crystallization of colloidal monolayers composed of diameter-tunable microgel spheres. Two-dimensional (2D) colloidal liquids were frozen homogenously into polycrystalline solids, and four 2D criteria for freezing were experimentally tested in thermal systems for the first time: the Hansen–Verlet freezing rule, the Löwen–Palberg–Simon dynamical freezing criterion, and two other rules based, respectively, on the split shoulder of the radial distribution function and on the distribution of the shape factor of Voronoi polygons. Importantly, these freezing criteria, usually applied in the context of single crystals, were demonstrated to apply to the formation of polycrystalline solids. At the freezing point, we also observed a peak in the fluctuations of the orientational order parameter and a percolation transition associated with caged particles. Speculation about these percolated clusters of caged particles casts light on solidification mechanisms and dynamic heterogeneity in freezing. [ABSTRACT FROM AUTHOR]

Megaprojects exert substantial influence on economics, society, and the environment on a global scale. Current theory-building research in the megaproject field mainly focuses on three perspectives—the socioeconomic system, systems engineering and project management, and complex organization and governance. Despite realizing the importance of megaprojects, we still lack a deep understanding of megaproject management and related organizational issues. Adopting organizational behavior (OB) theory as a point of departure, this study first reviewed the classic OB theory and current OB research status systematically. The classic OB theory was then introduced to the context of megaprojects in an attempt to build a theoretical framework of OB in megaprojects through bibliometric analysis and an integrative review approach. A multilevel framework across individual, group, project, and organizational fields was elaborated for OB research in the megaproject field, and based on the framework developed, future research directions in this research area were proposed and discussed. This research not only bridges the research gap in megaproject management from a new perspective, but also contributes to the enrichment and development of the classic OB theory in a new context. [ABSTRACT FROM AUTHOR]

Abstract Research question What is the diagnostic value of maternal kisspeptin in patients with asymptomatic first-trimester pregnancies, and what is the prognostic significance of kisspeptin versus beta-HCG in early pregnancies. Design Case-control study in academic medical centres. Patients with no confounding co-morbidities who conceived by IVF and intracytoplasmic sperm injection were analysed. Maternal serum samples were assessed at the time of pregnancy testing. Women who achieved a positive pregnancy test were asked to take serum samples 4 days later. According to the follow-up results, patients who experienced biochemical pregnancy loss (n = 24) and early miscarriage (n = 21), and women who achieved a viable pregnancy (n = 28), were included in this study. Serum samples were collected to detect kisspeptin and beta-HCG, respectively. Results Single serum determinations of kisspeptin and beta-HCG were correlated with the different pregnancy outcomes. Women who experienced biochemical pregnancy loss showed lower kisspeptin levels than those in groups B and C. No significant difference, however, was observed at the time of pregnancy testing in women who had experienced early miscarriage and those who had achieved viable pregnancy. Sequential measurements of serum kisspeptin are not as effective as beta-HCG in determining pregnancy outcome. Increased kisspeptin level was associated with reduced miscarriage risk. Conclusion Single serum measurement of kisspeptin is significantly altered in pregnant and non-pregnant women. However, it failed to discriminate between miscarriage and ongoing pregnancies in first-trimester pregnancy. Neither single nor sequential kisspeptin have higher diagnostic performance for miscarriage than beta-HCG in early stage. [ABSTRACT FROM AUTHOR]