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Finite Element Approximation of Stationary Fokker–Planck–Kolmogorov Equations with Application to Periodic Numerical Homogenization
No full textWe propose and rigorously analyze a finite element method for the approximation of stationary Fokker-Planck-Kolmogorov (FPK) equations subject to periodic boundary conditions in two settings: one with weakly differentiable coefficients, and one with merely essentially bounded measurable coefficients under a Cordes-type condition. These problems arise as governing equations for the invariant measure in the homogenization of nondivergence-form equations with large drifts. In particular, the Cordes setting guarantees the existence and uniqueness of a square-integrable invariant measure. We then suggest and rigorously analyze an approximation scheme for the effective diffusion matrix in both settings based on the finite element scheme for stationary FPK problems developed in the first part. Finally, we demonstrate the performance of the methods through numerical experiments
Bill & Ted’s Retcon Adventures: The Do-it-Later Retroactive Solution
Full text linkThe Bill & Ted film series has always employed a unique narrative device yet to be discussed in detail. In the series' first two films, the titular characters use a “do it later” approach through time travel, which I call “retroactive solution”, to solve the narrative problems at the respective climaxes. It has the same retroactive nature as the narrative device of retroactive continuity, or retcon, which is an inevitable but problematic plot device that facilitates reboots and sequels. The third, presumably final, film, Bill and Ted Face the Music (2020), would inadvertently pit these two narrative devices against each other and create a paradox. Through a series of analyses employing analytical philosophies of time travel and historicization, this paper synthesizes the two narrative devices, temporal paradoxes, Capitalist credit economies, and personal “mid-life crises” into the Bill & Ted series. In the process, it illuminates the usefulness of the time-travel genre for narratological case studies and cultural commentaries.published_or_final_versio
Model-free Change-Point Detection Using AUC of a Classifier
No full textIn contemporary data analysis, it is increasingly common to work with non-stationary complex data sets. These data sets typically extend beyond the classical low-dimensional Euclidean space, making it challenging to detect shifts in their distribution without relying on strong structural assumptions. This paper proposes a novel offline change-point detection method that leverages classifiers developed in the statistics and machine learning community. With suitable data splitting, the test statistic is constructed through sequential computation of the Area Under the Curve (AUC) of a classifier, which is trained on data segments on both ends of the sequence. It is shown that the resulting AUC process attains its maxima at the true change-point location, which facilitates the change-point estimation. The proposed method is characterized by its complete nonparametric nature, high versatility, considerable flexibility, and absence of stringent assumptions on the underlying data or any distributional shifts. Theoretically, we derive the limiting pivotal distribution of the proposed test statistic under null, as well as the asymptotic behaviors under both local and fixed alternatives. The localization rate of the change-point estimator is also provided. Extensive simulation studies and the analysis of two real-world data sets illustrate the superior performance of our approach compared to existing model-free change-point detection methods.</p
HiRes-LLaVA: Restoring Fragmentation Input in High-Resolution Large Vision-Language Models
No full textEnhancing urban solar irradiation prediction with shadow-attention graph neural networks: Implications for net-zero energy buildings in New York City
No full textAssessing building photovoltaic (PV) potential is crucial for urban energy planning and achieving Net-Zero Energy Building (NZEB) goals. However, urban-scale assessment still faces limitations. Most studies have neglected the importance of facade PV potential. Moreover, they often treat buildings as isolated entities, overlooking the impact of interactions between buildings, such as shading effects. To address these shortcomings, this study proposes a novel Shadow-Attention Graph Neural Network (SAGNN) to accurately predict solar irradiation for large-scale urban buildings. Analyzing 1.08 million buildings in New York City at a 1-meter spatial resolution, the study explores the potential for achieving NZEB and Net-Zero Electricity Building (NZEL) status. Results show that building rooftops and facades have annual PV power generation potential of approximately 29,851.9 GWh and 32,062.2 GWh, respectively. However, the PV potential is still insufficient to achieve the NZEB goal for the entire city. Nevertheless, utilizing both roof and facade PV can enable many areas to achieve NZEL. Cost-benefit analysis reveals that rooftop PV systems are more economically viable than facades, with a payback period of 7 years and a net-benefit of $71.98 billion over the 25-year life cycle. This research provides scientific decision support for urban PV planning and NZEB policy formulation
MSAB limits osteoarthritis development and progression through inhibition of β-catenin-DDR2 signaling
Full text linkThe aberrant activation of the canonical Wnt/β-catenin signaling has been identified as a significant contributor to the pathogenesis of osteoarthritis (OA), exacerbating OA symptoms and driving OA progression. Despite its potential as a therapeutic target, clinical translation is impeded by the lack of a targeting delivery system and effective drug candidate that can modulate steady-state protein levels of β-catenin at post-translational level. Our study addresses these challenges by offering a new approach for OA treatment. To overcome these challenges, we introduced a novel delivery system using human serum albumin (HSA) to deliver a small molecule β-catenin inhibitor, Methyl-Sulfonyl AB (MSAB). This system is designed to enhance the bioavailability of MSAB, ensuring its accumulation inside the joint space, and facilitating the degradation of β-catenin protein. We have demonstrated that MSAB, when delivered via HSA, not only effectively inhibits cartilage damage but also ameliorates OA-related pain in an OA mouse model. We then performed proteomic analysis and biochemical studies to determine the molecular mechanisms underlying the therapeutic effects of MSAB. We identified that discoidin domain receptor 2 (DDR2), a critical mediator in OA pathology, is a downstream molecule of β-catenin signaling and β-catenin/TCF7 directly controls DDR2 gene transcription. MSAB suppressed the DDR2 expression in chondrocytes. MSAB ameliorated OA progression and OA-associated pain through inhibition of β-catenin-DDR2 signaling. This study underscores the efficacy of MSAB/HSA in OA treatment, providing new insights into its molecular mechanism of OA. It suggests that targeted therapies with MSAB/HSA could be a new OA management strategy.published_or_final_versio
Integrated digit in noise test (iDIN) for rapid hearing and cognitive screening: a preliminary exploration
No full textBackground. Hearing and cognitive impairments are common amongst older adults, both affecting communication and are not easy to distinguish from each other. Objective. To preliminarily evaluate the efficacy of the integrated Digit in Noise Test (iDIN) for rapid screening of hearing and cognitive functions in older adults. Design. This cross-sectional cohort study was conducted at multiple clinical sites. Setting. Data collection occurred in sound-treated booths and quiet rooms at several outpatient clinics and elderly community centres. Subjects. The study included 107 older adults, aged 58–96, who were long-term residents of Hong Kong and native Cantonese speakers. Participants were selected through convenience sampling. Methods. Primary outcomes were the speech reception thresholds (SRTs) for 2-, 3- and 5-digit sequences with forward and 3-digit sequences with backward recall measured on iDIN. Hearing level was assessed using pure-tone audiometry. Cognitive function was assessed using the Hong Kong version of the Montreal Cognitive Assessment (HK-MoCA). Results. The 2-digit and 3-digit SRTs effectively distinguished participants with hearing loss, demonstrating high sensitivity (0.815 and 0.908, respectively) and specificity (0.905 and 0.853, respectively). The SRT3b-3f index effectively discriminated between participants who passed or failed the MoCA, with sensitivities of 0.727 and 0.781, and specificities of 0.885 and 0.787 using the two MoCA scoring methods. No significant correlation was found between SRT3b-3f and hearing levels after adjustment for educational background. Conclusions. iDIN demonstrates significant promise for rapid and effective screening of both hearing and cognitive impairments in older adults.</p
Web crippling behaviour of aluminium alloy square and rectangular hollow sections after high temperatures: Experiment, numerical analysis, and design approach
No full textThe test and numerical simulation were performed to clarify the residual web crippling (WC) resistance performance of the 6063-T5 aluminium alloy (AA) square hollow sections (SHSs) and rectangular hollow sections (RHSs) after different high temperatures (HTs). The tensile coupon test and transverse loading test were conducted. After HT exposure, a noteworthy reduction in strength properties and an increment in ductility occurred in the 6063-T5 AA. The resistance curve and failure mode of the 6063-T5 AA SHSs and RHSs under transverse loading were obtained through the experiment. There was a local buckling in the web near the loading area. The WC resistance performance of the 6063-T5 AA SHSs and RHSs after HT was investigated through numerical analysis. A parametric study including 240 numerical models was conducted to investigate the influence of HT, geometric dimension, and loading length on the resistance of the 6063-T5 AA SHSs and RHSs. The accuracy of the design approaches in AA Specification, AS/NZS Standard, EC9 Code, and NAS Specification on the results from test and numerical analysis was evaluated. The comparison stated that the current design approaches were inappropriate for the ultimate resistance prediction of the 6063-T5 AA SHSs and RHSs after HTs. HT exposure influenced the stress-strain properties of the 6063-T5 AA, which reduced the accuracy of the design approaches. The key coefficients in the unified WC equation in NAS Specification were suggested to be modified to improve the prediction accuracy on the resistance of the 6063-T5 AA SHSs and RHSs after HTs.link_to_subscribed_fulltex
Cation-regulated MnO2 reduction reaction enabling long-term stable zinc–manganese flow batteries with high energy density
No full textAqueous Zn–Mn flow batteries (Zn–Mn FBs) are a potential candidate for large-scale energy storage due to their high voltage, low cost, and environmental friendliness. However, the unsatisfactory performance due to the sluggish MnO2 reduction reaction (MnRR) kinetics leads to low discharge voltage (typically o1.7 V) and poor stability (typically o1000 cycles), which hinders their practical application. Here, we successfully achieve a reversible Mn2+/MnO2 reaction by a cation-regulated MnO2 formation/ decomposition process. The dual role of Mg2+ addition in locking free water and forming Mg-doped MnO2 compounds with enlarged atomic spacing was revealed, leading to excellent electrolyte stability and highly reversible MnRR. The Zn–Mn FBs with Mg2+ exhibit a high discharge voltage of 1.91 V at 20 mA cm-2 and superior long-term stability for over 2600 cycles, thus realizing a considerably high energy density (38.2 mW h cm-2 per cycle and 23.75 W h cm-2 cumulatively). This work underscores the importance of electrolyte engineering to the reversibility of Mn-based reactions and its potential for high power and energy density applications.link_to_subscribed_fulltex
Intersection of Adverse Childhood Experiences, Subjective Well-Being and Social Anxiety among Sojourners in China
No full textGrowing evidence suggests that adverse childhood experiences (ACEs) significantly threaten sojourners' well-being, depriving them of adaptive strategies to mitigate the negative influences. However, research examining social dysfunctions, such as social anxiety resulting from compromised well-being due to ACEs, remains limited. This study investigate how subjective well-being may mediate the relationship between ACEs and social anxiety among diverse groups of sojourners in China. Utilizing structural equation modeling, this study analyzed data from 470 sojourners in China to assess the direct effects of ACEs on social anxiety and whether subjective well-being mediates this relationship.The findings revealed that ACEs were not directly associated with social anxiety (β = 0.101, p = 0.089). However, ACEs were found to negatively impact subjective well-being (β = -0.483, p < 0.001). Additionally, subjective well-being was negatively associated with social anxiety (β = -0.268, p < 0.001), indicating that higher levels of subjective well-being correspond to lower levels of social anxiety. The study identified a full mediation effect, demonstrating that when ACEs diminish sojourners' subjective well-being, social anxiety tends to increase (β = 0.129, SE = 0.038, CI = [0.072, 0.198], p < 0.01), confirming the enervating effects of ACEs on social anxiety regardless of subjective well-being. No significant gender disparities were observed in the interrelationships among ACEs, subjective well-being, and social anxiety. Outcomes varied among students, expatriates, and business owners based on the model. Support and interventions should consider ACEs as risk factors for low subjective well-being, which can lead to social dysfunctions such as social anxiety. Addressing these factors is crucial for improving the overall well-being of sojourners.</p