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Chronic wounds present a complex pathological microenvironment characterized by bacterial infection, excessive reactive oxygen species (ROS), persistent inflammation, and impaired tissue regeneration. Metal-organic frameworks (MOFs) are promising wound-healing materials because their coordination structures, porous architectures, and metal nodes can be chemically programmed to respond to pathological cues. This Frontier highlights three inorganic-chemistry principles governing MOF-mediated wound repair: coordination bond dynamics, pore-confined delivery, and metal-node reactivity. We discuss how acidity, redox-active species, competing ions, and protein-rich exudates regulate framework evolution and therapeutic ion release; how pore engineering enables host-guest matching and stimuli-gated delivery; and how metal nodes and heterostructures mediate ROS generation or scavenging. Key challenges include evaluating framework evolution in realistic wound fluids, distinguishing intrapore loading from surface adsorption, achieving stage-specific redox regulation, and ensuring safe degradation and metal-ion release.

In order to solve the dispersion of nano-CaCO3 in the latex system and the instability of latex caused by high calcium ion activity, this paper proposes an efficient, mild and environmentally friendly method to prepare CaCO3@SiO2 core-shell nanostructured composites by sonochemical reaction, which obtains extremely low calcium ion activity and good dispersion in the latex system. The unique sonochemical process rapidly coats a dense SiO2 shell onto the nano-CaCO3 surface. The resulting product comprises a calcite-phase CaCO3 core and an amorphous SiO2 shell, which are covalently bonded through Ca-O-Si chemical bonds. The uniform and continuous SiO2 shell not only effectively improves the dispersion of nano-CaCO3 but also shields the surface calcium ion activity. The prepared CaCO3@SiO2 composite particles were dispersed into natural latex as fillers to prepare medical examination gloves with an extremely high addition amount of 30 phr. Owing to the effective shielding of surface calcium ion activity by the CaCO3@SiO2 core-shell structure and its good dispersion, the filler exhibits excellent processing stability and interfacial compatibility in the natural latex matrix, resulting in significantly improved mechanical properties including tensile strength, elongation at break and thermal aging resistance. This study provides a novel and efficient approach for the preparation of high-performance fillers for medical examination gloves.

Developing cost-effective adsorbents for capturing gaseous iodine is highly significant. Herein, we report a two-step electrodeposition/hydrothermal strategy to fabricate a series of composites of Cu2S/Ni3S2/Cu/NF-n (NF is nickel foam, n = 0.5, 1, and 2, representing millimoles of thiourea added) and Cu2S/Ni3S2/NF-4, which exhibit excellent iodine capture performance. Partial sulfidation of the deposited Cu0 and NF (Ni0) substrate enables the co-existence of bimetallic sulfides of Cu2S and Ni3S2 with Cu0/Ni0 metals. The optimized Cu2S/Ni3S2/Cu/NF-1 composite shows a significantly high iodine sorption capacity of 2832 mg g-1, by virtue of its snowflake-like sheet morphology loaded with nanoparticles. The S2- ions and Cu0 and Ni0 (from NF and Ni3S2) all participate in the reduction of I2 molecules to I- ions, which then combine with Cu+ and Ni2+ forming metal iodides of CuI and NiI2. Density functional theory (DFT) calculations show negative iodine adsorption energies (Ead) at Cu, Ni and S sites, indicating spontaneous adsorption, and the Cu2S/Ni3S2 heterojunction has a significantly reduced Ead, showing that the interface effect effectively enhances iodine capture. Charge density difference calculations confirm inter-phase and intra-phase electron transfers, effectively modulating the electronic structure. Synergistic effects of phase interfaces among Cu2S, Ni3S2, Cu0 and Ni0 within Cu2S/Ni3S2/Cu/NF contribute to the remarkable iodine capture capability. This work offers new insights for designing cost-efficient metal sulfide adsorbents for iodine capture from radioactive waste.

The rational design of matrix metalloproteinase (MMP) inhibitors, such as those targeted for MMP-14, prioritizes the native Zn(II) cofactor. The elevated levels of Cu(II), which are characteristic of the tumor microenvironment, are often overlooked. In this study, we investigated the Cu(II) coordination chemistry of selected MMP-14 inhibitors using potentiometric titrations, UV-Vis spectroscopy, circular dichroism, and density functional theory. Our findings reveal a striking inversion of metal selectivity in comparison with previously studied Zn(II) complexes. While Inhibitor 1 (Inh1) retains high specificity for the native Zn(II) active site, Inhibitor 4 (Inh4) exhibits exceptional thermodynamic stability with Cu(II) (pKd = 11.87). Inh4 favors copper over zinc by more than six orders of magnitude. This remarkable stability comes from a highly pre-organized, histamine-like mixed N/O donor environment and an extended poly-glycine tail. This tail adopts a 310-helical conformation that additionally stabilizes the coordination site and minimizes the entropic penalty of complexation. These results demonstrate that while Inh1 remains a highly specific candidate for targeted MMP-14 inhibition, the pronounced selectivity gap of Inh4 transforms it into a highly specific Cu(II) scavenger. This study highlights the critical risk of off-target metal sequestration in the tumor microenvironment while simultaneously opening the door to the potential repurposing of Inh4 as a targeted, copper-depleting agent in anti-angiogenic therapies.

Spin qubits based on electron spins are promising platforms for quantum information science due to their ability to form controllable superposition states with long coherence times. While most molecular spin qubits have focused on S = 1/2 systems, high-spin systems offer an alternative approach with access to multilevel quantum states. In particular, high-spin Mn(II) (S = 5/2) centers possess zero orbital angular momentum (L = 0), resulting in weak spin-orbit coupling that suppresses spin-lattice relaxation and prolongs phase memory times. The central transition (MS = -1/2 ↔ +1/2) behaves similarly to an S = 1/2 system, enabling robust and stable spin coherence, whereas the outer transitions (MS = ±5/2 ↔ ±3/2 and ±3/2 ↔ ±1/2) provide additional functionality through interactions with nuclear spin systems and external electric fields. Recent studies on Mn(II)-doped metal-organic frameworks and discrete Mn(II) complexes diluted in diamagnetic matrices demonstrate tunable spin relaxations, highlighting their potential as multilevel quantum units for advanced quantum operations such as Grover-type algorithms. Despite these promising features, molecular high-spin qubits remain less explored than their S = 1/2 counterparts, and further investigations into spin-vibration coupling, structural design, and external field control are required. Overall, high-spin metal complexes represent an emerging and versatile platform for next-generation spin-based quantum technologies.

The aims of this study were to characterize symptom clusters and examine the influence of social determinants of health (SDOH) on symptom cluster membership among people receiving maintenance hemodialysis and experiencing chronic pain. This study utilized baseline data collected from the 643 patients enrolled in the HOPE Consortium Trial designed to test the efficacy of an intervention to reduce chronic pain. Latent profile analyses were performed to characterize symptom clusters. SDOH variables were collected using self-report and the Census Geocoder. Five distinct clusters of symptoms were identified including (1) moderate levels of anxiety, (2) average level of all symptoms, (3) low levels of all symptoms, (4) low levels of anxiety, and (5) high levels of all symptoms. When compared to the symptom cluster with average level of symptoms, higher everyday discrimination scores were associated with higher odds of membership in the clusters reflecting moderate levels of anxiety and high levels of all symptoms. Greater residential segregation was associated with higher odds of being in the low anxiety cluster; and greater income inequality was associated with higher odds of membership in the moderate level anxiety symptom cluster. Multi-level interventions targeting discrimination and those living in areas with the greatest income inequality are warranted to reduce symptom burden and improve quality of life in this patient population. TRIAL REGISTRATION: ClinicalTrials.gov #NCT04571619 PERSPECTIVE STATEMENT: Social determinants of health (SDOH) such as discrimination and income inequality were associated with higher anxiety while segregation resulted in lower levels of anxiety reflecting the complex relationship between SDOH and mental health. Multi-level interventions targeting discrimination and income inequality are warranted to reduce symptom burden in this patient population.

Emergency tracheal intubation outside the operating theatre carries increased risk for patients. Guidelines caution against high dose propofol for induction in this context, due to associated haemodynamic instability. This study aimed to describe induction strategies and adverse events for these patients in UK practice. We conducted a prospective, multicentre cross-sectional service evaluation of adults who required emergency tracheal intubation outside the operating theatre. Data were collected as a convenience sample by anaesthetic and critical care teams using an online form. Primary outcomes were the selection and dose of induction drugs. Secondary outcomes were: vasopressor co-administration; severe hypotension (systolic blood pressure <&#x2009;80&#x2009;mmHg); severe hypoxia (peripheral oxygen saturation <&#x2009;80%); and cardiac arrest. Twenty-three NHS hospitals reported 250 emergency tracheal intubations. Not including 17 (7%) performed during cardiac arrest, there were 233 rapid sequence inductions. Propofol was used in 147 (63%); fentanyl in 172 (74%); ketamine in 53 (23%); and midazolam in 51 (22%). Propofol with fentanyl was the most common combination (97/233, 42%), at median (IQR [range]) doses of 1.4 (0.8-2.0 [0.04-3.3]) mg.kg-1 and 2.0 (1.3-2.9 [0.5-6.0]) &#x3bc;g.kg-1, respectively. Severe hypotension affected 24/219 (11%) patients with recorded post-induction blood pressures. Severe hypoxia affected 14/221 (6%) patients with recorded post-induction oxygen saturations. Post-induction cardiac arrest occurred in 6/233 (3%) patients. For patients who did not receive pre-emptive vasopressors at induction, 40/105 (38%) subsequently required vasopressor administration. Patients who required tracheal intubation outside operating theatres experienced high rates of post-induction hypotension. Propofol was the most used induction drug, often at doses typical for elective anaesthesia. Pre-emptive vasopressor use was inconsistent. These practices deviate from existing guidelines and represent a modifiable risk factor for adverse events. We recommend standardised protocols for tracheal intubation outside operating theatres, including guidance on induction drug selection, dose and pre-emptive vasopressor use. Researchers collected information from 250 adults who needed an emergency breathing tube inserted outside an operating theatre in 23 NHS hospitals across the UK. They recorded which medicines doctors used to put patients to sleep, the doses they gave, whether medicines were used to support blood pressure and whether patients had serious problems such as very low blood pressure, low oxygen levels or cardiac arrest. Putting in a breathing tube during an emergency is riskier than in a planned operation. Current guidelines recommend using lower doses of some anaesthetic medicines, such as propofol, because high doses can make blood pressure drop dangerously low. The researchers wanted to see what doctors were doing in everyday practice and whether patients were having complications. Propofol was the medicine used most often, usually at doses similar to those used for planned operations. Around one in 10 patients developed dangerously low blood pressure after being given their anaesthetic, while about one in 20 had very low oxygen levels. A small number of patients had a cardiac arrest after the breathing tube was inserted. Many patients also needed medicines to raise their blood pressure after the procedure, but these medicines were not always given before problems developed. The study suggests that using more consistent guidelines for choosing anaesthetic drugs, giving the right dose and protecting blood pressure could make emergency intubation safer.

In this work, sea urchin-shaped CuO hierarchical microspheres assembled from two-dimensional nanosheets were synthesized via a facile one-step hydrothermal route for n-pentanol detection. Structural characterization studies confirmed the pure phase and porous hierarchical architecture of the as-obtained material, which possesses abundant active sites and efficient gas diffusion pathways. Gas sensing tests showed that the sensor based on sea urchin-like CuO microspheres presents a low optimal operating temperature of 175 &#xb0;C, much lower than those of most previously reported n-pentanol sensors. At 175 &#xb0;C, the sensor delivered a high response value of 9.2 toward 100 ppm n-pentanol, along with fast response/recovery times of 45 s and 23 s, respectively. Moreover, it maintained a stable sensing performance even under high relative humidity (90% RH), overcoming the poor humidity tolerance of conventional semiconductor gas sensors. Combined with material structure and surface chemical analysis, the enhanced sensing performance is attributed to the unique hierarchical structure and abundance of adsorbed oxygen species on the CuO surface. With the merits of low power consumption, fast response dynamics and superior environmental adaptability, the developed CuO sensor is promising for practical n-pentanol monitoring in complex atmospheric and industrial environments.

C2-alkylated imidazolium salts reacted with carbon disulfide and cesium carbonate under mild, aerobic conditions to afford imidazolium-dithiocarboxylate zwitterions bearing 2,6-diisopropylphenyl or mesityl substituents on their nitrogen atoms. The addition of CS2 took place regioselectively at the exocyclic C2&#x3b1; position of the starting materials and four new compounds were isolated in satisfactory to high yields. Two of them featured a chiral center and were obtained as racemic mixtures. Compared to previous strategies that required a strong base to deprotonate the imidazolium salts, followed by the nucleophilic addition of the intermediate N-heterocyclic olefins (NHOs) onto CS2, our method involved only one step and relied on a weak, innocuous base. Moreover, it did not necessitate the use of dry and degassed solvents under an inert atmosphere, making it more environmentally friendly and easier to implement. The four NHO&#xb7;CS2 zwitterions served as ligands to prepare a small library of heteroleptic ruthenium-arene complexes with the generic formula [RuCl(p-cymene)(S2C&#xb7;NHO)](PF6) and homoleptic dicationic complexes of the type [Ru(S2C&#xb7;NHO)3](PF6)2. These chelates are the first examples of coordination compounds based on NHO&#xb7;CS2 inner salts. They were fully characterized using various analytical techniques and the molecular structures of three of them were determined. We also synthesized the IMes&#xe001;CH2-d2&#xb7;CS2 betaine in three steps from 1,3-dimesitylimidazolium chloride (IMes&#xb7;HCl) using a straightforward procedure, and we used it as an isotopically labeled ligand to form the stable [RuCl(p-cymene)(S2C&#xb7;CH2&#xe001;IMes-d2)](PF6) complex in 95% yield. This experiment served as a proof of concept to demonstrate the potential of our methodology for the design of new deuterated metallodrugs. Lastly, the catalytic activity of the eight Ru(S2C&#xb7;NHO) chelates was probed in the transfer hydrogenation of acetophenone with isopropanol and potassium hydroxide. Gratifyingly, they proved superior to their Ru(S2C&#xb7;NHC) cousins featuring xanthinium-8-dithiocarboxylate ligands derived from caffeine and theophylline.

A series of six new heteroleptic copper(I) complexes of the [Cu(N^N)(P^P)]+ type are reported in which P^P is 4,5-bis(diphenylphosphano)-9,9-dimethylxanthene (xantphos) and N^N are ligands based on 1,10-phenanthroline (phen) with different degrees of steric encumbrance in their 2,9-positions (R = H or CH3), and varying substitution on their imidazo backbone. The synthesized complexes were fully characterized by NMR spectroscopy, high-resolution mass spectrometry, as well as elemental and single-crystal X-ray analysis. Their electrochemical and photophysical properties were investigated, including supporting theoretical calculations, and HER catalytic investigations were conducted to probe potential reactivity. While the luminescence properties vary across the series in dichloromethane (DCM) and tetrahydrofuran (THF) solvents, selected complexes act as strong emitters, achieving photoluminescence quantum yields of up to 47%. In particular, [Cu(L3b)(xantphos)]PF6 exhibits a long emission lifetime of 8.52 &#x3bc;s in THF.

Second-order nonlinear optical chromophores based on coordination compounds offer an interesting route to enhance molecular hyperpolarizability through low-energy charge-transfer excited states and the tunable donor/acceptor character of metal centers. While lanthanide complexes are widely explored for luminescence and magnetism, their second-order NLO properties remain comparatively underinvestigated, and cationic lanthanide systems have, to the best of our knowledge, not been explored. In this context, we designed and synthesized in a simple and rapid way two new lanthanide complexes based on a europium cation or gadolinium cation and the same zinc anion: [Eu(hfa)2(tetrag)]+&#xb7;[Zn(hfa)3]- and [Gd(hfa)2(tetrag)]+&#xb7;[Zn(hfa)3]-. Structural and spectroscopic characterization confirms the formation of well-defined cation-anion assemblies in which the lanthanide &#x3b2;-diketonate cation is counterbalanced by a zinc anion counterpart. The second-order nonlinear optical response was evaluated in solution by means of the Electric-Field Induced Second Harmonic generation (EFISH) technique which affords &#x3bc;&#x3b2;EFISH values. Both compounds present values much higher than that of the benchmark Disperse Red One, rendering them of particular interest for future applications such as in electro-optic modulators.

Four new iron(III) complexes of the type [Fe(L)Cl3] 1-4, where L is N,N-(bispyridin-2-ylmethyl)-N-(thiophene-2-methyl)amine (L1), N,N-(bispyridin-2-ylmethyl)-N-(thiophene-2-ethyl)amine (L2), N-(pyridin-2-ylmethyl)-N-(1-methylimidazole-2-methyl)-N-(thiophene-2-methyl)amine (L3) and N-(pyridin-2-ylmethyl)-N-(1-methylimidazole-2-methyl)-N-(thiophene-2-ethyl)amine (L4), have been synthesized and studied as functional models for catechol dioxygenases. In the X-ray structures of [Fe(L1)Cl3] 1 and [Fe(L3)Cl3] 3, the 3N ligands are facially coordinated to Fe(III) in a distorted octahedral geometry. DFT studies reveal that L1 is meridionally coordinated in the 3,5-di-tert-butylcatecholate (DBC2-) adduct [Fe(L1)(DBC)Cl] 1A, whereas L2-L4 are facially coordinated in [Fe(L2-L4)(DBC)Cl] 2A-4A. In O2-saturated methanol solution, 1A undergoes catechol cleavage with the highest rate constant for the second-order reaction (kO2: 1 (11.38 &#xb1; 0.02 &#xd7; 10-3 M-1 s-1) > 3 (4.45 &#xb1; 0.02 &#xd7; 10-3 M-1 s-1) > 4 (1.58 &#xb1; 0.02 &#xd7; 10-3 M-1 s-1) > 2 (1.28 &#xb1; 0.02 &#xd7; 10-3 M-1 s-1)) to yield major amounts of extradiol cleavage products (1, 94%; 2, 90%; 3, 52%; 4, 80%), with the highest extradiol-to-intradiol product selectivity (E/I: 1, 94/1; 2, 18/1; 3, 1/1; 4, 4/1). Upon replacing a pyridyl nitrogen in 1A with an imidazolyl nitrogen to obtain 3A, and extending the thiophenylmethyl arm in 1A and 3A to obtain 2A and 4A, respectively, both the rate and extradiol cleavage yield decrease. DFT studies reveal that the intermediate [Fe(L1)(DBSQ)(O2)]+ contains meridionally coordinated L1 and antiferromagnetic interaction between (DBSQ)FeIII and O2&#x2d9;-, which facilitates efficient extradiol cleavage.

The nickel cyclam complex (cyclam = 1,4,8,11-tetraazacyclotetradecane) remains one of the most selective and efficient catalysts for the electrochemically driven conversion of CO2 into CO in aqueous media. Although the mechanisms associated with CO2 electroreduction by this complex have been well investigated in homogeneous and heterogeneous cases, few computational studies so far have compared the effect of N- or C-substitution on the catalytic properties. Moreover, the effect of explicit water or counter-anion molecules has very rarely been considered in theoretical studies with this family of complexes. In that context, we have performed computational density functional theory investigations on the electrocatalytic reduction of CO2 by considering three different Ni complexes bearing cyclam-based ligands, which have been previously investigated. In-depth analysis for each step of the catalytic cycle has allowed us to draw general structure-reactivity relationships for both trans-I and trans-III isomers of each calculated structure.

Di(silylamido)stannylenes find application in chemical synthesis, catalysis and deposition of thin film materials. Homoleptic bis(N-alkyl-substituted-silylamido)stannylenes (i.e. [Sn{NtBu(TMS)}2], TMS = trimethylsilyl) have previously been reported to possess limited thermal stability. Here, we describe the experimental and computational investigation of the thermal decomposition of [Sn{NR(TMS)}2] [R = iPr, Cy, tBu, Ad (Ad = 1-adamantyl), CPh3]. For aliphatic N-alkyl groups, DFT calculations support an intramolecular C(sp3)-H activation by deprotonation of the TMS group via &#x3c3;-bond metathesis (&#x3c3;BM), which forms a reactive four-membered heterocycle that is followed by disproportionation. When the N-alkyl group is substituted for the trityl group (-CPh3), the homoleptic stannylene could not be isolated, with the deprotonation of a neighbouring ortho-phenyl C(sp2)-H position via &#x3c3;BM occurring at room temperature. The resultant five-membered heterocyclic Sn(II) intermediate rapidly tetramerises into [Sn{&#x3ba;2-Ph'CPh2N(TMS)}]4, which is stable with respect to disproportionation.

Symmetric solid oxide fuel cells (SSOFCs) offer advantages such as simplified manufacturing and operation; however, their performance is often constrained by insufficient oxygen vacancy concentration and sluggish oxygen ion transport in conventional electrodes. To overcome these limitations, a novel Ba-doped perovskite system, La0.3Sr0.7-xBaxFeO3-&#x3b4; (LSBaF-x, x = 0.1-0.3), was developed through A-site engineering. Rietveld refinement of XRD data confirmed that LSBaF-0.2 exhibits a well-defined cubic perovskite structure, overcoming the hexagonal distortion of undoped LSF. Electrochemical performance tests revealed a significant reduction in polarization resistance (Rp) to 0.136 &#x3a9; cm2 in H2 at 800 &#xb0;C, along with a decreased apparent activation energy of 0.93 eV for the oxygen reduction reaction (ORR) in air. When integrated into SSOFCs, the LSBaF-0.2 electrode achieved exceptional performance, delivering peak power densities (PPDs) of 1235 mW cm-2 at 800 &#xb0;C and 690 mW cm-2 at 700 &#xb0;C. Moreover, continuous operation for 200 h at 800 &#xb0;C demonstrated excellent stability. These results highlight Ba doping as an effective strategy to stabilize cubic LSF and optimize dynamics, and LSBaF-0.2 is regarded as a highly promising electrode material for SSOFC applications.

Vision symptoms are frequent after concussion and can often persist and be disabling. Most studies on concussion with persisting concussion symptoms (PCS) provide limited attention to vision symptoms. Vision symptoms occur in 69-82% of patients with PCS and commonly include photophobia, blurred vision, and computer screen intolerance (CSI) - a syndrome induced by viewing electronic screens including computer, cell phone, tablet, or TV screens. We discuss the vision symptoms that may arise and persist after a concussion. Unfortunately, the pathophysiology of many of these symptoms is unknown, and we examine current views of the mechanisms potentially involved with a focus on CSI. We also evaluate the effectiveness of the currently available treatments. Our aim is to improve recognition and treatment of concussion induced vision symptoms through an understanding of their pathophysiology and the efficacy of available treatments. Enhanced recognition and understanding may facilitate improved treatment for these debilitating symptoms that compromise the quality of life and hinder return to school or work for many concussed individuals. We aim to aid ophthalmologists, optometrists, and other vision scientists who are frequently called upon to diagnose and treat patients with these symptoms.

Surgical site infections (SSIs) after colectomy are a major source of morbidity, mortality, and cost. Despite evidence supporting prevention bundles, reliable implementation remains challenging. We describe the implementation of a colectomy SSI bundle guided by the Translating Research into Practice (TRIP) model, featuring novel electronic health record (EHR)-enabled compliance monitoring. A pre/post quasi-experimental study compared baseline (n&#x2009;=&#x2009;227) and post-implementation (n&#x2009;=&#x2009;164) colectomies at a community teaching hospital. An Epic (Epic Systems Corporation, Verona, WI) EHR dashboard monitored compliance. The primary outcome was the National Healthcare Safety Network (NHSN) Standardized Infection Ratio (SIR). SSI rates decreased from 10.6% to 4.9% (relative risk 0.46, 95% CI: 0.21-0.99, p&#x2009;=&#x2009;0.051). The SIR decreased from 2.04 to 0.895 (relative risk 0.44, 95% CI: 0.19-0.95, p&#x2009;=&#x2009;0.037), indicating fewer SSIs than expected. Compliance was high across most elements. The TRIP model provided a replicable implementation framework. The EHR dashboard enabled actionable compliance monitoring without requiring capital investment. A colectomy SSI prevention bundle, guided by the TRIP model and supported by an EHR dashboard, achieved a statistically significant reduction in SIR and a clinically meaningful decrease in SSI rates.

Postoperative C5 palsy is a debilitating complication of cervical spine surgery with unclear etiology. A previous study of 12 patients proposed a three-variable model to predict postoperative C5 palsy based on MRI measurements of the anteroposterior diameter of the spinal canal (APD), foraminal diameter (FD), and cord-lamina angle (CLA). The initial paper reported an area under the receiver operating characteristic (ROC) curve (AUC) of 0.97, with a sensitivity of 91% and specificity of 100%. This study aimed to validate the three-variable model and its individual components in a larger patient cohort. Adult patients who underwent anterior or posterior cervical discectomy and fusion at C4-5 with subsequent C5 palsy were retrospectively identified (2010-2023). Postoperative C5 palsy was defined as a new or increased deltoid/biceps weakness on manual motor testing. Patients with C5 palsy were propensity score-matched 1 to 3 to a control group based on age, sex, Charlson Comorbidity Index score, procedure type, and levels fused. A biostatistician used the APD, FD, and CLA MRI measurements to calculate ROC curves, sensitivities, and specificities for single- and three-variable predictive models of postoperative C5 palsy. A total of 42 patients with C5 palsy were matched to 126 controls. There were no significant differences in preoperative APD (mean 9.20 vs 9.45 mm, p = 0.426), minimum FD (mean 1.82 vs 1.90 mm, p = 0.609), or maximum CLA (mean 38.8&#xb0; vs 38.5&#xb0;, p = 0.867) between the C5 palsy and control groups. The APD had an AUC of 0.455, sensitivity of 0.912, and specificity of 0.148. The minimum FD had an AUC of 0.501, sensitivity of 0.765, and specificity of 0.330. The maximum CLA had an AUC of 0.513, sensitivity of 0.765, and specificity of 0.348. When applied collectively, the three-variable predictive model performed similarly to chance, yielding an AUC of 0.519 (95% CI 0.410-0.628), sensitivity of 0.676, and specificity of 0.452. In a large, well-matched validation cohort, the preoperative MRI parameters of the APD, FD, and CLA were not predictive of postoperative C5 palsy, both individually and as a three-variable model. The etiology of C5 palsy remains poorly understood and reliable preoperative predictors have yet to be identified. The previously proposed three-variable model demonstrated inconsistent predictive utility for postoperative C5 palsy, and the model should be interpreted with caution before more rigorous external validation.

The electrochemical synthesis of hydrogen peroxide via the two-electron oxygen reduction reaction (2e- ORR) represents a sustainable alternative to the energy-intensive anthraquinone process. Its viability hinges on developing cost-effective catalysts with high activity and selectivity. Here, we report a rationally designed multi-dimensional heterostructure Ni-MoxC, composed of zero-dimensional Ni and MoxC nanoparticles and two-dimensional carbon sheets. By systematically tuning the Mo/Ni atomic ratio, we identify a volcano-type dependence of the 2e- ORR performance on catalyst composition. The optimal Ni-MoxC-10 catalyst exhibits exceptional selectivity for H2O2 (>93%) and remarkable stability over 27 hours of operation. Mechanistic investigations reveal that the performance apex arises from a synergistic interfacial effect induced by the precise stoichiometry. The optimal Mo/Ni ratio maximizes the formation of an active Ni-MoxC heterointerface, which collectively optimizes the adsorption energy of the *OOH intermediate, suppresses H2O2 decomposition, and facilitates rapid proton/electron transfer. This work highlights the critical role of compositional tuning in maximizing interfacial synergy within complex heterostructures, providing a guiding principle for the design of advanced electrocatalysts for on-demand H2O2 production.