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To accommodate the advancement of next-generation power electronics toward high-level integration and miniaturization, it is imperative to develop polymer dielectrics that maintain superior energy storage performance under thermal extremes. Traditional aromatic polymers (e.g., polyetherimide, PEI) suffer from severe charge delocalization at elevated temperatures due to inherent charge-transfer complexes (CTCs) within their conjugated structures, resulting in sharply increased leakage current and deteriorated energy storage performance. In this work, we propose a molecular conformation engineering strategy that incorporates sterically hindered, twisted fluorine-substituted fluorene moieties into the PEI backbone, successfully decoupling the trade-off between thermal stability and high-efficiency energy storage. Integrating experimental characterization with theoretical calculations reveals the underlying mechanism by which molecular conformation engineering regulates macroscopic electrical performance from a multiscale perspective: the inherent rigidity of the fluorene skeleton provides a robust molecular scaffold that ensures thermomechanical reliability at elevated temperatures. Meanwhile, the non-coplanar, twisted geometry disrupts long-range π-π stacking, thereby hindering intermolecular charge transfer and synergizing with strategic fluorination to reduce leakage current through reinforced electron localization. Consequently, the optimized PEI-FFDA achieves a superior discharge energy density of 3.44 J cm-3 at 200 °C (10 Hz), approximately 2.5 times that of pristine PEI (1.38 J cm-3), with exceptional reliability over 105 cycles. This work establishes an effective molecular design paradigm for intrinsically robust high-temperature dielectrics.

Dynamical control of quantum matter is a challenging, yet promising direction for probing strongly correlated states. Motivated by recent experiments in twisted MoTe_{2} that demonstrated optical control of magnetization, we propose a protocol for probing magnetization dynamics in flat-band ferromagnets. We investigate the nucleation and dynamical growth of magnetic bubbles prepared on top of a false vaccum in both itinerant ferromagnets and spin-polarized Chern insulators. For ferromagnetic metals, we emphasize the crucial role of a nontrivial quantum geometry in the magnetization dynamics, which in turn also provides a probe for the quantum metric. Furthermore, for quantum Hall ferromagnets, we show how properties of chiral edge modes localized at domain-wall boundaries can be dynamically accessed. Our Letter demonstrates the potential for nonequilibrium protocols to control and probe strongly correlated phases, with particular relevance for twisted MoTe_{2} and graphene-based flat-band ferromagnets.

We report a combined experimental and theoretical study of the formation and decay dynamics of a ground-state twisted intermediate (TI) involved in the ultrafast internal conversion of UV-excited pyrimidine nucleosides and nucleotides in aqueous solution. Infrared transient absorption spectroscopy identifies a TI featuring a strongly twisted C5=C6 double bond, and its quantum yield (ΦTI) and lifetime (τTI) are determined for structurally distinct nucleosides and nucleotides. Photohydration rates (khyd) measured under continuous 266 nm irradiation correlate directly with ΦTI × τTI, providing unambiguous evidence that the TI mediates the hydration reaction. Comparison of C5-H and C5-CH3 derivatives reveals pronounced reductions in both ΦTI and khyd upon methylation. Quantum mechanics/molecular mechanics dynamical simulations show that TI formation requires sufficient nuclear momentum along the TI-forming coordinate at the conical intersection, whereas vibrational energy randomization induced by C5 methylation and solvent interactions diminishes this momentum and consequently ΦTI. The TI is neither diradical nor zwitterionic but instead contains an elongated, highly reactive C5=C6 double bond whose polarization and hydration reactivity are attenuated by C5 methylation. Consistently, the normalized reactivity index, khyd/(ΦTI × τTI), is substantially lower for C5-methylated compounds. A high activation barrier limits the photohydration quantum yield (∼0.01), and τTI is primarily governed by isomerization back to the planar ground-state structure.

A 7-year-old neutered male domestic shorthair cat was presented for evaluation of a large intra-abdominal mass. Contrast-enhanced CT revealed a pedunculated hepatic mass measuring 15 × 9.5 × 6.5 cm arising from the papillary process of the caudate lobe, without evidence of metastasis. A three-port laparoscopic liver lobectomy was performed. The mass, attached by a torsed pedicle, was excised using a bipolar advanced energy vessel sealing device (ENSEAL; Ethicon). Histopathology confirmed a primary hepatic fibrosarcoma with complete resection. The cat recovered uneventfully, was discharged the following day and received five cycles of adjuvant doxorubicin (Adriamycin; Pfizer), maintaining an excellent quality of life and stable disease for at least 3 years. This is the first report of laparoscopic liver lobectomy in a cat with a large torsed hepatic mass. The case demonstrates that minimally invasive liver lobectomy can be successfully performed in feline patients, even in challenging cases involving substantial or torsed lobes. Removing a part of a cat liver using a minimally invasive surgery A 7-year-old male cat was found to have a large growth on his liver. Scans showed that the growth was attached by a twisted stalk, but there was no sign that it had spread elsewhere. The cat underwent a minimally invasive surgery, called a laparoscopic liver lobectomy, to remove the affected part of the liver. The growth was successfully removed, and laboratory testing confirmed it was a type of liver tumour called fibrosarcoma. The cat recovered very well from surgery and went home the next day. He also received additional chemotherapy to reduce the chance of the tumour coming back. Three years after the surgery, the cat remained healthy, happy and showed no signs of disease. This case is important because it is the first report of minimally invasive liver surgery being used in a cat with a large, twisted liver tumour. It shows that even complex liver problems in cats can be treated safely with less invasive techniques, which can help cats recover faster and maintain a good quality of life.

Elucidating excited-state conformational dynamics in D-π-A systems is central to the development of functional molecules. In particular, the emergence of twisted intramolecular charge transfer (TICT) states offers a powerful handle to regulate electronic relaxation pathways through molecular design. Herein, a systematic investigation of two structurally similar D-π-A chromophores (SV27 and SV31) is engineered to either suppress or facilitate excited-state twisting. The control molecule SV27 exhibits limited conformational flexibility and relaxes predominantly through a locally excited state, whereas the strategic incorporation of a sterically demanding donor fragment in SV31 induces substantial excited state torsional reorganization, leading to the stabilization of a TICT state. A combination of steady-state spectroscopy, time-resolved fluorescence measurements, and quantum chemical calculations reveals a strong coupling between molecular architecture, excited-state potential energy surfaces, and charge transfer dynamics. Solvent-dependent studies further demonstrate that higher polarity of the medium selectively stabilizes the twisted charge separated state, which is identified as a crucial element for the accessibility of TICT. Upon leveraging this sensitivity to the local environment, the TICT-active chromophore SV31 is employed as a highly responsive fluorescent probe for trace water detection in organic solvents, achieving trace level sensitivity (30 ppm). Altogether, this study offers a rational framework by correlating molecular architecture with excited-state twisting and charge separation, providing a rationale for activating TICT and laying the foundation for the development of advanced functional molecular architectures for the detection of water.

The recently developed cgNA+ model of double-stranded DNA (dsDNA) accurately predicts equilibrium distributions (in solution) of linear dsDNA fragments of arbitrary sequence, expressed in enhanced Curves+ internal coordinates. This article introduces cgNA+min, a computational framework built on the cgNA+ energy to compute sequence-dependent energy-minimizing configurations of topologically closed dsDNA minicircles with a range of linking numbers. We employ a chain rule to re-express the cgNA+ energy in absolute coordinates using quaternions, which drastically simplifies the minicircle looping constraint. Additionally, a semi-analytic method generates sequence-dependent, reasonably low-energy, initial guesses for minicircles of prescribed link, which enhances efficiency of our energy-minimizing algorithm. Leveraging this efficiency, we analyze 190K random DNA sequences with lengths from 88 to 106 base pairs, revealing multiplicities over different values of link, and of distinct energy minimizers at the same link. The length dependence of the sequence-average of cgNA+min predicted minicircle energies at prescribed link matches closely to the twisted worm-like chain model, while the variation of those energies with sequence at fixed length and link is shown to be comparatively large. For various specific sequence families, we verify that cgNA+min minicircle energies closely correlate with energies derived from experimentally measured cyclization $J$-factors.

Mitochondrial viscosity is a key microenvironmental parameter regulating its function, and its dysregulation is associated with various diseases. However, achieving specific and dynamic monitoring of mitochondrial viscosity remains challenging. To address this, we developed a novel near-infrared fluorescent probe, FTZ-BTZ, based on a twisted intramolecular charge transfer mechanism. The probe demonstrates high sensitivity (R2 = 0.9906), excellent selectivity, good stability, and low cytotoxicity in viscosity detection. Colocalization imaging confirmed its precise mitochondrial targeting capability, with a Pearson's coefficient of 0.9052. Using this probe, we successfully achieved real-time, in situ visualization of dynamic changes in mitochondrial viscosity within living cells. These changes were induced by various pharmacological stimuli, including lipopolysaccharide, dexamethasone, nystatin, and monensin. Specifically, we established the concentration-dependent response of mitochondrial viscosity to monensin. Further in vivo experiments showed that FTZ-BTZ can effectively distinguish viscosity gradients induced by different drug stimulations in mouse models. The FTZ-BTZ probe developed in this work provides a high-performance molecular tool for real-time investigation of mitochondrial viscosity-related physiological and pathological processes at the subcellular level.

Electrocatalytic urea production through C-N coupling offers a sustainable alternative to traditional energy-intensive processes; however, its practical implementation is still limited by thermodynamically unfavorable pathways and slow C-N coupling kinetics. We design systematically a series of twisted two-dimensional heterostructures composed of BCN and MXenes, denoted as M2CO/BCN (M = Ti, V, Cr), with six representative rotation angles (0°, 10.89°, 49.11°, 60°, 70.89°, and 109.11°). Density functional theory calculations reveal that interfacial twisting effectively modulates charge redistribution and electronic coupling, thereby promoting CO and NO activation. Thermodynamic analyses combined with constrained ab initio molecular dynamics simulations demonstrate that twisting markedly reduces both the free energy variation and the kinetic barriers associated with the C-N coupling step. As a result, V2CO/BCN-109.11° exhibits the lowest reaction potential of -0.23 V. Our findings establish interfacial twisting as an effective strategy for simultaneously optimizing thermodynamics and kinetics in electrocatalytic urea synthesis. Finally, we apply the Sure Independence Screening and Sparsifying Operator (SISSO) approach to identify a physically interpretable descriptor that quantitatively correlates twist-induced structural factors with catalytic performance, providing a key insight into the structure-activity relationship.

Lipid droplet accumulation is a pathological hallmark of nonalcoholic fatty liver disease (NAFLD); however, the utility of current lipid droplet-targeted fluorescent probes for in vivo diagnosis is hindered by shallow tissue penetration and strong background autofluorescence. To overcome these challenges, here, we report three donor-acceptor-acceptor solvatochromic probes (CTBT-ANPy, PTBT-ANPy, and MOPTBT-ANPy) with tunable electron-donating groups, enabling near-infrared (NIR) imaging of lipid droplets and in vivo NAFLD diagnosis. Owing to multiple intramolecular interactions and restriction of twisted intramolecular charge transfer, these probes exhibit intense NIR emissions (up to 709 nm, quantum yield of 34.2%) in low-polarity media. These lipophilic probes display high lipid-droplet specificity with bright light-up signals and wash-free capacity. With the aid of NIR-emissive MOPTBT-ANPy, in vivo high-contrast fluorescent discrimination of NAFLD in a mouse model was successfully achieved. This study underscores the potential of high-performance NIR probes for noninvasive accurate NAFLD diagnosis and monitoring.

Isolated fallopian tube torsion (IFTT) is a rare condition in which the fallopian tube undergoes torsion without ovary involvement. The causes of IFTT vary widely, ranging from intrinsic abnormalities of the fallopian tube itself to extrinsic factors affecting the peritubal environment. Here, we report a case of IFTT concomitant with an adenomatoid tumor arising from the fallopian tube. A 49-year-old triparous patient presented with sudden-onset lower abdominal pain. Imaging findings revealed a 3-cm solid mass in the subserosal area of the left fallopian tube, and laparoscopy confirmed IFTT involving a dark red and solid mass. Histologically, an adenomatoid tumor was identified in the twisted fallopian tube. Adenomatoid tumors of the fallopian tube are typically small, asymptomatic, and identified incidentally during gynecologic surgeries or imaging; therefore, this tumor is an extremely rare cause of IFTT. Adenomatoid tumors in the fallopian tube, even those as small as 3 cm, can result in torsion.

Incorporating topologically nontrivial molecules (e.g., catenanes) is an emerging strategy for tuning properties of polymer networks, but the fundamental roles of these molecules remain poorly understood. Herein, we report a unified gel system employing isomeric linkers with distinct topologies, which allows for cross-gel comparison and elucidation of how topology governs mechanical and dynamic properties in polymeric materials. Our gels feature a panel of phenanthroline-based macrocyclic molecules as linkers, which adopt structures including a large macrocycle, a flexible catenane, and, through metal coordination, a rigidified catenane and a twisted figure-eight structure. By mechanical and thermodynamic analysis and simulations, we identify topology-dependent coordination and conformational entropy as the key factors driving the gels' mechanical responses. We reveal that the toughness and energy dissipation capacity of the gels correlate directly to the conformational change allowed by each topology, proportional to the "hidden length" that can be released by the linkers. Surprisingly, metal-ligand bonds primarily tune the initial linker conformation rather than dissipate energy through bond dissociation, while they simultaneously enhance network dynamics. Our findings could guide the selection of topological molecules for engineering advanced polymer materials.

Non-planar aromatic hydrocarbons display distorted π-frameworks that give rise to unique optoelectronic properties. Among the different strategies for generating non-planar aromatic hydrocarbons, steric overcrowding has afforded numerous twisted structures displaying helical or alternate twists, whereas bent structures remain rare. Herein, we report a pyrene-fused azaacene derivative in which eight strategically positioned phenyl substituents enforce bending of the aromatic core rather than twisting, generating a negatively curved, saddle-shaped structure. Single-crystal x-ray diffraction reveals large deviations from planarity with bend angles of 41° and 34°, stabilised by intramolecular π-π stacking between facing phenyl rings.

Most planar organic fluorescent dyes suffer from aggregation-caused quenching (ACQ) due to strong intermolecular π-π interactions, severely limiting their utility in practical applications. To address this, we developed a strategy based on cyclohexadienone spiro molecules that exhibit aggregation-induced emission (AIE) and dual fluorescence properties. Using spiro-PT-OMeTAD as a model, we demonstrated that its dual emission peaks arise from a locally excited (LE) state and a twisted intramolecular charge transfer (TICT) state. Structural analysis revealed that the cyclohexadienone spiro architecture is critical to this performance: the electron-withdrawing carbonyl group facilitates charge separation (promoting TICT), while the asymmetric spiro geometry provides steric hindrance that prevents close stacking and ACQ. The universality of this mechanism was confirmed by synthesizing a series of derivatives (spiro-PT-BA, spiro-PT-PA, and spiro-PT-MA), all of which displayed similar dual fluorescence. Finally, leveraging these optical characteristics, we successfully used spiro-PT-BA as a polarity-sensitive probe to detect water content in tetrahydrofuran (THF) and as a visual temperature sensor.