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Global brand cities: Driving the global leading cities of high value industry through world city network with global brands
No full textThis study introduces the concept of a "Global Brand City," which suggests that global cities emerge from a world city network formed by global brands. Our goal is to identify the relationship between global cities and high-value-added industries. High value industries are closely linked to urban employment creation and economic development, especially in global cities. By defining global brands as a transnational actor of high value industries, we constructed and analyzed a network using various centrality indices. Our proposed method revealed differences between the producer-service industry based global cities and the global brand cities based on the high value industries. Global brand headquarters cities tend to be concentrated in industrial and economic cores of developed countries. In contrast, global brand branch office cities tend to be associated with market entry or talent attraction. These two types of cities interact through their respective differentiation and competitiveness, forming high value industries and the world city network of global brands. The proposed method can highlight how global cities play a pivotal role in high-value industries.
The effect of target depth on performance of multi-directional tapping task in virtual reality
No full textModelling gap selection of mobile phone distracted drivers at roundabouts: A mixed multinomial logit with heterogeneity-in-means approach
No full textGap selection at roundabouts is a critical driving task whereby drivers simultaneously evaluate gaps in circulatory traffic and control their vehicle dynamics. Whilst this task is already challenging and increases workload, it becomes more difficult when drivers concurrently use mobile phones. A few studies suggest that the gap selection of distracted versus undistracted drivers is not different; however, the determinants of gap selection could vary, and heterogeneous gap selection can also be observed if appropriate modelling techniques are applied. To this end, this study finds that past studies either applied simple pairwise comparisons or developed fixed parameter models, which are incapable of deciphering distracted driver-level heterogeneity in gap selection. Motivated by this research gap, the current study focusses on understanding the relationship between mobile phone distraction and gap selection at roundabouts using a mixed multinomial logit model. Thirty-two young, licensed drivers, with equal male and female representation, were asked to select a gap for entry into the roundabout whilst considering giving way to oncoming traffic. In the driving simulation environment, participants faced a roundabout entry scenario thrice, with each corresponding to no phone, handheld, and hands-free driving conditions. To model drivers' gap selection outcomes (small, medium, and large/no gap), a mixed multinomial logit model is developed, accounting for repeated measures of experiment design, capturing unobserved heterogeneity, and allowing the mean of a random parameter to vary. The model has two random parameters (hands-free and handheld driving conditions), whereas the fixed parameters include age, gender, acceleration noise, initial post encroachment time, and selfreported crash history. The model suggests heterogeneous effects of handheld and hands-free driving conditions on gap selection, implying that distracted drivers may select large and small gaps depending on the context. The model also indicates that heterogeneity-in-means for the handheld parameter is associated with driving experience, implying that experienced distracted drivers are more likely to select medium gaps. The findings of this study provide in-depth information about understanding gap selection mechanisms and forming policies for distracted drivers.
Impulsive loss decision-making associated with aberrant meso- /habenular-cortical functional networks in young adults with major depressive disorder with suicidal ideation
No full textSuicide, which involves a decision-making process biased toward a lethal option that may result in the loss of one's own life, remains a major public health concern, particularly among young adults with major depressive disorder (MDD). This study investigates whether impaired decision-making in the context of loss distinguishes young adults with MDD and suicidal ideation (MDSI) from those without suicidal ideation (MDNSI) and healthy controls (HC), and explores the underlying neurocomputational mechanisms. A total of 110 young adults (23 MDSI, 31 MDNSI, and 56 HC) underwent resting-state functional magnetic resonance imaging (fMRI) and completed a two-armed bandit decision-making task designed to separate loss and reward contexts. Accuracy and computational parameters reflecting decision impulsivity were compared among groups using analysis of covariance. Logistic regression was performed to identify features predicting MDSI among MDD patients. Response time modeling was conducted to differentiate loss-related impulsivity from indecisiveness. Functional connectivity analyses focused on the ventral tegmental area (VTA) and habenula networks to identify alterations mediating loss-decision impulsivity in MDSI. MDSI patients uniquely exhibited premature, value-insensitive impulsive decisions in the loss context, distinguishing them from MDNSI patients independent of depression severity. These decision abnormalities were not attributable to indecisiveness. In contrast, reward-based decision impairments were shared across both MDD subgroups. Disruptions in resting-state functional connectivity within the VTA-orbitofrontal and habenula-default mode networks in MDSI fully mediated their loss-specific impulsivity. These findings highlight loss-specific decision impulsivity and associated neural dysconnectivity as potential early markers of suicide risk, offering novel insights into targeted intervention strategies.
Low-Complexity Algorithm for Minimum Rate Maximization in UAV-Enabled OFDMA Networks
No full textIn this letter, we consider an uncrewed aerial vehicle (UAV)-enabled orthogonal frequency division multiple access (OFDMA) network, where the UAV flies and hovers along the predefined trajectory to transmit data to the clustered users on the ground. We propose a resource allocation algorithm, consisting of the transmit power and the subcarrier allocation (TSA) and the hovering time allocation (HTA), to maximize the minimum rate under the transmit power constraint. To reduce computational complexity while balancing user rate performance, the TSA iteratively reallocates the transmit power and the subcarrier between users with the maximum and the minimum rates within each cluster. Subsequently, the HTA reassigns the hovering time between users from different clusters with the maximum and the minimum rates to balance inter-cluster performance. Simulation results show that the proposed algorithm effectively improves the minimum rate with reduced complexity, even in the OFDMA networks with a large number of subcarriers.
NiH-Catalyzed Homobenzylic Hydroalkylation of Aryl Alkenes Using Sulfoxonium Ylides
No full textWe present here the first example of NiH-catalyzed homobenzylic hydroalkylation of aryl alkenes mediated by a nickel carbene radical, achieving the elusive beta-selectivity with excellent regiocontrol. Mechanistic investigations suggest that this transformation is enabled by the preferential engagement of NiH with bench-stable sulfoxonium ylides, whose unique chelation properties promote carbene activation prior to alkene insertion. The resulting nickel carbene radical is proposed to undergo selective beta-addition, followed by intramolecular metal hydride transfer and protodemetalation. The reaction exhibits broad scope across aryl, heteroaryl, and complex bioactive alkene derivatives, as well as diverse sulfoxonium ylides. This work establishes a new mechanistic platform for NiH catalysis, expanding the synthetic repertoire for site-selective alkene functionalization.
The Competition for Partners in Matching Markets
No full textWe study the competition for partners in two-sided matching markets with heterogeneous agent preferences, with a focus on how the equilibrium outcomes depend on the connectivity in the market. We model random partially connected markets, with each agent having an average degree d in a random (undirected) graph and a uniformly random preference ranking over their neighbors in the graph. We formally characterize stable matchings in large random markets with small imbalance and find a threshold in the connectivity d at log2n (where n is the number of agents on one side of the market), which separates a "weak competition" regime, where agents on both sides of the market do equally well, from a "strong competition" regime, where agents on the short (long) side of the market enjoy a significant advantage (disadvantage). Numerical simulations confirm and sharpen our theoretical predictions, and demonstrate robustness to our assumptions. We leverage our characterizations in two ways: First, we derive prescriptive insights into how to design the connectivity of the market to trade off optimally between the average agent welfare achieved and the number of agents who remain unmatched in the market. For most market primitives, we find that the optimal connectivity should lie in the weak competition regime or at the threshold between the regimes. Second, our analysis uncovers a new conceptual principle governing whether the short-side enjoys a significant advantage in a given matching market, which can moreover be applied as a diagnostic tool given only basic summary statistics for the market. Counterfactual analyses using data on centralized high school admissions in a major U.S. city suggests that both our design insights and our diagnostic principle have practical value.
Investigating the Nature of PRM:SH3 Interactions Using Artificial Intelligence and Molecular Dynamics
No full textUnderstanding the binding interactions within protein-peptide complexes is crucial for elucidating key physicochemical phenomena in biological systems. Among the outcomes of these interactions, biomolecular condensates have recently emerged as vital players in various cellular functions including signaling. Complexes such as PRM:SH3 are known to undergo condensation, yet the chemical interactions and governing factors driving these behaviors remain poorly understood. In this study, we combine AlphaFold2 and molecular dynamics simulations to investigate the binding nature of PRM:SH3. Our findings reveal that proline-to-alanine mutations enhance flexibility, weakening the binding affinity, while charge-altering mutations modify the binding mode and influence the binding strength. Notably, the PRM(H) series shows that binding is primarily driven by local flexibility and the hydrophobic effect. Furthermore, we demonstrate that the root-mean-square deviation and dendrogram height are correlated to experimental dissociation constants. These insights provide a framework for understanding the binding behaviors of protein-peptide complexes and offer an effective approach for studying similar systems.
Surface Fluorination Shielding of Sulfide Solid Electrolytes for Enhanced Electrochemical Stability in All-Solid-State Batteries
No full textDespite their high Li+ conductivity and deformability, sulfide solid electrolytes suffer from limited electrochemical stability, which prevents all-solid-state batteries (ASSBs) from reaching their full performance potential. Herein, a facile surface fluorination strategy is presented for Li6PS5Cl using XeF2 as a solid-state fluorinating agent, enabling a scalable dry process at moderate temperatures. An approximate to 37.3 nm-thick uniform fluorinated layer is coated on an Li6PS5Cl surface, preserving 82.8% of the initial Li+ conductivity (from 2.9 x 10(-)3 only to 2.4 x 10(-)3 S cm(-)(1) at 30 degrees C). The underlying fluorination mechanism, deduced through systematic investigations using X-ray photoelectron spectroscopy, X-ray Rietveld refinement, nuclear magnetic resonance, and density functional theory calculations, involves the formation of surface oxidative byproducts and F substitution within the lattice. When applied to LiNi0.90Co0.05Mn0.05O2 electrodes in LiNi0.90Co0.05Mn0.05O2||(Li-In) half cells at 30 degrees C, the fluorinated Li6PS5Cl substantially improves the electrochemical performance, delivering superior discharge capacities (e.g., 186.9 vs 173.6 mA h g-1 at 0.33C), capacity retention, and safety characteristics compared to unmodified Li6PS5Cl. This enhancement is attributed to the formation of a robust fluorinated cathode electrolyte interphase that mitigates Li6PS5Cl oxidation. Finally, the stable operation of a pouch-type LiNi0.90Co0.05Mn0.05O2||Li ASSB is demonstrated, highlighting the scalability of the proposed approach.
Experimental demonstration of dual-polarization multiplexed optical phased array empowered by inverse design
No full textThis paper presents a dual-polarization multiplexed optical phased array (OPA) implemented on a 220 nm silicon-on-insulator (SOI) platform, enabling continuous beam steering across TE and TM modes. While effectively guiding TE- and TM-polarized light, the proposed OPA on this platform faces the challenge of overcoming the intrinsically high effective refractive index disparity between the two modes upon radiation from the grating antenna. To mitigate this challenge, key OPA components - polarization beam combiner, polarization-independent beam splitter, and index-modulated pixelized grating antenna - were optimized using inverse design methods and integrated, enabling efficient and seamless beam steering across both polarizations. With a 100 nm wavelength tuning range and dual-polarization operation, the fabricated 64-channel OPA achieves a notable longitudinal beam steering range of 34.9 degrees across the TE and TM modes, along with full 2-D beam steering capability. The experimental results confirm the effectiveness of the proposed approach, highlighting its potential for advancing the next-generation LiDAR and optical wireless communication systems.