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As electronic products become smaller and more powerful, there is an increasing need for effective heat dissipation. An effective heat exchange method is necessary for the equipment to function reliably in a compact space. To tackle the limitations of current microfluidic cooling technology, including difficulty in manufacturing, maintenance, and cost reduction, a heat exchange method with a simple system is proposed in this work. This method is based on the electrocapillary effect, using eutectic gallium–indium alloy droplets with high thermal conductivity, surface tension, and controllability as the basic unit. An electric field is applied to generate unevenly distributed charges in the electric double layer on the droplet surface, thereby creating a surface tension gradient that can drive the surrounding solution to flow. Simultaneously, the oscillation of the droplet can also intensify the disturbance of the solution. The violent disturbance of the solution causes the heat transfer mode to change from conduction to convective heat transfer and greatly reduces the thermal resistance, resulting in a substantial increase in heat flux. For this heat transfer method, the temperature distribution and flow characteristics of the solution in low-frequency oscillating and direct-current-biased alternating current electric fields are studied, and the effect of voltage, frequency, and the number of droplets on heat transfer enhancement is clarified. Compared with conduction without internal disturbance, the heat flux can be increased by up to 110% based on the combined effect of two droplets. This work provides a solution for enhancing the heat transfer of microfluidics. [ABSTRACT FROM AUTHOR]

The decoration of metal active sites to regulate the catalytic activity of polymeric photocatalysts is highly significant. In this study, a photosensitive phenanthroline-containing covalent triazine framework (PT-CTF) was synthesized and various metal ions (Co2+, Ni2+, and Zn2+) were incorporated into the PT-CTF through interactions with the phenanthroline unit to enhance the photocatalytic CO2 reduction performance. The characterization results showed that all metallized PT-CTF (M-PT-CTF) materials exhibited significantly improved photochemical properties and CO2 adsorption capabilities. In particular, the Ni-coordinated PT-CTF (Ni-PT-CTF) demonstrated an impressive CO generation rate of 784.5 μmol g−1 h−1 and a selectivity of 96.6% without any photosensitizers, which was approximately 10.2 times higher than that of the pristine PT-CTF under visible light irradiation. Experimental studies and theoretical calculations indicated that the enhanced photocatalytic performance was due to the incorporated Ni sites in the PT-CTF structure, which facilitated charge carrier dynamics, reduced energy barriers for *COOH formation, and enhanced CO2 activation and CO desorption. This work provides insight for the designing and fabrication of advanced polymeric photocatalysts at the molecular level for efficient CO2 conversion. [ABSTRACT FROM AUTHOR]

Hyperplasia of mesenteric tissues in Crohn's disease, called creeping fat (CrF), is associated with surgical recurrence. Although microbiota translocation and colonization have been found in CrF, convincing mouse phenotypes and the underlying mechanisms of CrF formation remain unclear. Utilizing single-nucleus RNA (snRNA) sequencing of CrF and different mouse models, we demonstrate that the commensal Achromobacter pulmonis induces mesenteric adipogenesis through macrophage alteration. Targeted metabolome analysis reveals that L-kynurenine is the most enriched metabolite in CrF. Upregulation of indoleamine 2,3-dioxygenase 1 (IDO1) enhances kynurenine metabolism and drives mesenteric adipogenesis. Leveraging single-cell RNA (scRNA) sequencing of mouse mesenteric tissues and macrophage-specific IDO1 knockout mice, we verify the role of macrophage-sourced L-kynurenine in mesenteric adipogenesis. Mechanistically, L-kynurenine-induced adipogenesis is mediated by the aryl hydrocarbon receptors in adipocytes. Administration of an IDO1 inhibitor or bacteria engineered to degrade L-kynurenine alleviates mesenteric adipogenesis in mice. Collectively, our study demonstrates that microbiota-induced modulation of macrophage metabolism potentiates CrF formation. [Display omitted] • The commensal Achromobacter pulmonis induces mesenteric adipogenesis • Macrophage-derived L-kynurenine via IDO1 is responsible for mesenteric adipogenesis • L-kynurenine-induced adipogenesis is mediated by AHR activation in adipocytes • Targeting kynurenine metabolism alleviates the formation of mesenteric adipogenesis Wu et al. reveal that the commensal Achromobacter pulmonis induces mesenteric adipogenesis through macrophages alteration. Mechanistically, macrophage-derived L-kynurenine via indoleamine 2,3-dioxygenase 1 (IDO1) promotes adipogenesis by aryl hydrocarbon receptor (AHR) activation in adipocytes. Targeting kynurenine metabolism with an IDO1 inhibitor or bacteria engineered to degrade L-kynurenine alleviates mesenteric adipogenesis. [ABSTRACT FROM AUTHOR]

Objectives: To investigate changes in the optical and mechanical properties of novel zirconia ceramics applied in dentistry after Er:YAG laser debonding and to evaluate the feasibility and value of reusing zirconia restorations debonded by an Er:YAG laser. Methods: Four types of zirconia ceramics were investigated: self-glazed zirconia (SGZ), 3Y-TZP, 4Y-PSZ and 5Y-PSZ. Forty rectangular (25 mm*8 mm*1.5 mm) specimens were fabricated for each zirconia type, and a total of 160 specimens were manufactured. The zirconia specimens were divided into four subgroups according to the applied Er:YAG laser debonding process: the control group, 4 W laser group, 5 W laser group, and 6 W laser group. For each subgroup, 10 specimens were subjected to color tests (color difference (△E) and transparency parameter (TP) tests) and subsequent mechanical tests (flexural strength (FS), elastic modulus (EM), Vickers hardness (VH) and surface roughness (Ra) tests). The △E, TP, FS, EM, VH and Ra values were measured and calculated. One random sample from each subgroup was observed by SEM. Statistical analyses were performed by one-way ANOVA followed by post hoc comparisons (α = 0.05). Results: The △E and TP values after Er:YAG laser debonding were not significantly different among the subgroups (P > 0.05). However, the 6 W laser group had the highest △E and lowest TP. The ranges of changes in △E and TP were below the clinically detectable threshold (△E = 1.2, △TP = 1.33). In terms of the mechanical properties, there were no significant differences in the FS, EM, VH or Ra among the subgroups. No obvious microcracks were detected on the surfaces of the zirconia specimens during SEM. Conclusions: Er:YAG laser debonding does not obviously affect the optical or mechanical properties of novel zirconia ceramics in dentistry. Moreover, it is potentially feasible and valuable to reuse zirconia restorations after Er:YAG laser debonding. [ABSTRACT FROM AUTHOR]

RationaleAtrial fibrillation (AF) is the most common arrhythmia, and advanced age is an inevitable and predominant AF risk factor. However, the mechanisms that couple aging and AF propensity remain unclear, making targeted therapeutic interventions unattainable.ObjectiveTo explore the functional role of an important stress response JNK (c-Jun N-terminal kinase) in sarcoplasmic reticulum Ca2+ handling and consequently Ca2+-mediated atrial arrhythmias.Methods and resultsWe used a series of cutting-edge electrophysiological and molecular techniques, exploited the power of transgenic mouse models to detail the molecular mechanism, and verified its clinical applicability in parallel studies on donor human hearts. We discovered that significantly increased activity of the stress response kinase JNK2 (JNK isoform 2) in the aged atria is involved in arrhythmic remodeling. The JNK-driven atrial proarrhythmic mechanism is supported by a pathway linking JNK, CaMKII (Ca2+/calmodulin-dependent kinase II), and sarcoplasmic reticulum Ca2+ release RyR2 (ryanodine receptor) channels. JNK2 activates CaMKII, a critical proarrhythmic molecule in cardiac muscle. In turn, activated CaMKII upregulates diastolic sarcoplasmic reticulum Ca2+ leak mediated by RyR2 channels. This leads to aberrant intracellular Ca2+ waves and enhanced AF propensity. In contrast, this mechanism is absent in young atria. In JNK challenged animal models, this is eliminated by JNK2 ablation or CaMKII inhibition.ConclusionsWe have identified JNK2-driven CaMKII activation as a novel mode of kinase crosstalk and a causal factor in atrial arrhythmic remodeling, making JNK2 a compelling new therapeutic target for AF prevention and treatment.

Introduction: White matter hyperintensities (WMH) are commonly associated with balance and gait disturbances. Little is known whether WMH may affect post-stroke balance and gait recovery. We aim to investigate the association of post-stroke balance and gait recovery with imaging marker of WMH on magnetic resonance imaging (MRI). Methods: This prospective cohort study will enroll consecutive patients with first-ever ischemic hemisphere stroke, between September 2023 and December 2024. Clinical data will be collected on day 30 ± 3 and at 3 months after stroke onset. WMH on FLAIR are graded according to the modified Fazekas scale. Resting-state functional MRI (rs-fMRI) and diffusion tensor imaging (DTI) will be acquired to evaluate functional and structural connectivity. The primary endpoint is balance recovery, defined as a Postural Assessment Scale for Stroke score of 32 or higher at 3 months. The secondary endpoint is gait recovery, assessed using the modified Fugl-Meyer Gait Assessment at 3 months. We will investigate the association of post-stroke balance and gait recovery with WMH severity as well as WMH-related functional and structural connectivity. Conclusion: The study may contribute to clarify the effect of WMH on post-stroke balance and gait disorder recovery. [ABSTRACT FROM AUTHOR]