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Coherent phonon modes supported by plasmonic nanoparticles offer prospective applications in chemical and biological sensing. Whereas the characterization of these phonon modes often requires single-particle measurements, synthetic routes to narrow size distributions of nanoparticles permit ensemble investigations. Recently, the synthesis of highly monodisperse gold tetrahedral nanoparticles with tunable edge lengths and corner sharpnesses has been developed. Herein, we characterize a size series of these nanoparticles in colloidal dispersion via transient absorption spectroscopy to examine their mechanical and plasmonic responses upon photoexcitation. Oscillations of transient absorption signals are observed in the plasmon resonance and correspond to the lowest-order radial breathing modes of the nanoparticles, the frequencies of which are affected by the edge length and truncation of the corners. Homogeneous quality factor values ranging from 24 to 34 are observed for the oscillations that convey potential utility in mass-sensing and plasmon-exciton-coupling photonics schemes. Finite-difference time domain and finite element analysis calculations establish specific optically relevant phonon modes.

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ConspectusThe role of quantum mechanical coherences or coherent superposition states in excited state processes has received considerable attention in the last two decades largely due to advancements in ultrafast laser spectroscopy. These coherence effects hold promise for enhancing the efficiency and robustness of functionally relevant processes, even when confronted with energy disorder and environmental fluctuations. Understanding coherence deeply drives us to unravel mechanisms and dynamics controlled by order and synchronization at a quantum mechanical level, envisioning optical control of coherence to enhance functions or create new ones in molecular and material systems. In this frontier, the interplay between electronic and vibrational dynamics, specifically the influence of vibrations in directing electronic dynamics, has emerged as the leading principle. Here, two energetically disparate quantum degrees of freedom work in-sync to dictate the trajectory of an excited state reaction. Moreover, with the vibrational degree being directly related to the structural composition of molecular or material systems, new molecular designs could be inspired by tailoring certain structural elements.In the realm of chemical kinetics, our understanding of the dynamics of chemical transformations is underpinned by fundamental theories, such as transition state theory, activated rate theory, and Marcus theory. These theories elucidate reaction rates by considering the energy barriers that must be overcome for reactants to transform into products. Those barriers are surmounted by the stochastic nature of energy gap fluctuations within reacting systems, emphasizing that the reaction coordinate, the pathway from reactants to products, is not rigidly defined by a specific vibrational motion but encompasses a diverse array of molecular motions. While less is known about the involvement of specific intramolecular vibrational modes, their significance in certain cases cannot be overlooked.In this Account, we summarize key experimental findings that offer deeper insights into the complex electronic-vibrational trajectories encompassing excited states afforded from state-of-the-art ultrafast laser spectroscopy in three exemplary processes: photoinduced electron transfer, singlet-triplet intersystem crossing, and intramolecular vibrational energy flow in molecular systems. We delve into the rapid decoherence, or loss of phase and amplitude correlations, of vibrational coherences along promoter vibrations during subpicosecond intersystem crossing dynamics in a series of binuclear platinum complexes. This rapid decoherence illustrates the vibration-driven reactive pathways from the Franck-Condon state to the curve crossing region. We also explore the generation of new vibrational coherences induced by impulsive reaction dynamics rather than by the laser pulse in these systems, which sheds light on specific energy dissipation pathways and thereby on the progression of the reaction trajectory in the vicinity of the curve crossing on the product side. Another property of vibrational coherences, amplitude, reveals how energy can flow from one vibration to another in the electronic excited state of a terpyridine-molybdenum complex hosting a nonreactive dinitrogen substrate. A slight change in vibrational energy triggers a quasi-resonant interaction, leading to constructive wavepacket interference and ultimately intramolecular vibrational redistribution from a Franck-Condon active terpyridine vibration to a dinitrogen stretching vibration, energizing the dinitrogen bond.

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Although vibronic coupling phenomena have been recognized in the excite state dynamics of transition metal complexes, its impact on photoinduced electron transfer (PET) remains largely unexplored. This study investigates coherent wavepacket (CWP) dynamics during PET processes in a covalently linked electron donor-acceptor complex featuring a cyclometalated Pt(ii) dimer as the donor and naphthalene diimide (NDI) as the acceptors. Upon photoexciting the Pt(ii) dimer electron donor, ultrafast broadband transient absorption spectroscopy revealed direct modulation of NDI radical anion formation through certain CWP motions and correlated temporal evolutions of the amplitudes for these CWPs with the NDI radical anion formation. These results provide clear evidence that the CWP motions are the vibronic coherences coupled to the PET reaction coordinates. Normal mode analysis identified that the CWP motions originate from vibrational modes associated with the dihedral angles and bond lengths between the planes of the cyclometalating ligand and the NDI, the key modes altering their π-interaction, consequently influencing PET dynamics. The findings highlight the pivotal role of vibrations in shaping the favorable trajectories for the efficient PET processes.

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Objective: To analyze the clinical characteristics, treatment, and outcomes of children with complete left bundle branch block (CLBBB) mediated by maternal autoantibodies. Methods: A retrospective analysis was conducted on nine children diagnosed with maternal autoantibody-mediated CLBBB, treated at Beijing Anzhen Hospital and Fujian Provincial Hospital from March 2015 to August 2023. Their clinical characteristics, electrocardiographic and echocardiographic findings before and after treatment were reviewed. Paired sample t-test was used for inter-group comparison. Results: Among the mothers, 6 had positive antinuclear antibodies (ANA), 5 had anti-Sjogren syndrome antigen A antibodies, and 3 had anti-Ro-52 antibodies. The cohort included one female and eight male children, diagnosed with CLBBB at the age of 1 (2, 13) months. The positive autoantibodies in the infants, consisted with maternal antibodies, were detected within the first 3 months of life among 3 cases. Treatments included anti-heart failure therapy, myocardial nutritional support, intravenous immunoglobulin (IVIG) and glucocorticoids. Before treatment, the levels of troponin I (0.175 (0.060, 10.270) µg/L) and N-terminal pro-B-type natriuretic peptide (420 (327, 12 865) ng/L) were elevated, which normalized in most cases after treatment. Post-treatment, the QRS duration significantly shortened compared to pre-treatment ((137±15) vs.(169±25) ms, t=3.76, P<0.001), and the QTc interval significantly decreased ((433±41) vs. (514±27) ms, t=4.95, P=0.001). Before treatment, varying degrees of mitral and tricuspid regurgitation and marked interventricular septal dyskinesia were observed in echocardiography. After treatment, valve regurgitation and ventricular septum motion significantly improved, with a marked increase in left ventricular ejection fraction ((51±13)% vs. (27±6)%, t=-6.66, P<0.001). Conclusions: Maternal autoantibody-mediated CLBBB in children presents with chronic heart failure in infancy. Early treatment with anti-heart failure medications, IVIG and glucocorticoids can improve clinical symptoms.

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Objective: To compare the efficacy of gasless robotic surgery through transaxillary approach and open surgery for papillary thyroid carcinoma (PTC). Methods: The data of patient undergoing robotic surgery through transaxillary approach and traditional open surgery for PTC at the Sun Yat-sen Memorial Hospital, Sun Yat-sen University, from November 2016 to June 2023 were retrospectively analyzed. A 1∶1 propensity score matching (PSM) was performed to balance age, sex, extent of surgery, tumor size, capsule invasion, and multifocality. Surgical data, postoperative pathological data, complications, postoperative 2-month visual analog scale (VAS) scores for aesthetics, and follow-up data were compared between the two groups. Results: A total of 728 PTC patients were included. There were 339 patients in the robotic group, among which 262 were female (77.3%) and 77 were male (22.7%), with the age of [M (Q1, Q3)] 39 (32, 46) years and a body mass index (BMI) of 22.8 (20.7, 25.0) kg/m². Meanwhile, 389 patients were in the open group, among which 290 were female (74.6%) and 99 were male (25.4%), with the age of 47 (38, 55) years and a BMI of 23.2 (21.3, 25.5) kg/m2. Further analysis after PSM (there were 264 cases in both groups) showed that in the subtotal thyroidectomy and central neck dissection (LT+CCND) subgroup, the robotic group had longer operative time, higher blood loss, and greater drainage volume compared with the open group [100 (80, 130) min vs 60 (50, 80) min; 10 (10, 20) ml vs 10 (10, 20) ml; 103 (69, 145) ml vs 75 (57, 98) ml; all P<0.001], and the central lymph node metastasis rate was higher in the robotic group [45.6% (57/125) vs 31.8% (47/148), P=0.019]. In the total thyroidectomy and central neck dissection (TT+CCND) subgroup, the robotic group also had longer operative time, higher blood loss, and greater drainage volume compared with the open group [150 (110, 180) min vs 85 (75, 100) min; 20 (10, 20) ml vs 10 (10, 20) ml; 155 (107, 206) ml vs 90 (70, 120) ml; all P<0.001]. The incidence of chest skin numbness at 3 months postoperatively was higher in the robotic group compared with the open group (12.9% vs 0, P<0.001), while there were no statistically significant differences in other postoperative complications (all P>0.05). The VAS score at 2 months postoperatively was higher in the robotic group compared with the open group [9 (9, 9) vs 8 (7, 9), P<0.001]. Three cases of contralateral lobe recurrence occurred in the open group, while there were no case of recurrence in the robotic group. The 5-year overall survival rate was 100.0% in both the robotic and open groups, and there was no statistically significant difference in the 5-year disease-free survival rate between the robotic and open groups (100.0% vs 98.6%, P=0.068). Conclusion: Gasless robotic surgery through transaxillary approach for total thyroidectomy or lobectomy in the treatment of PTC is safe, feasible, and effective, with good cosmetic outcomes and comparable efficacy to traditional surgery.

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Vitamin D is a critical fat-soluble vitamin for the nervous system. Research suggests a potential link between vitamin D deficiency and attention-deficit hyperactivity disorder (ADHD), particularly in children and adolescents. The core symptoms of ADHD are associated with deficits in striatal functions, and maintaining sufficient levels of vitamin D may help prevent or alleviate ADHD symptoms. However, the molecular changes in the striatum caused by vitamin D supplementation that may contribute to the brain processes linked to ADHD symptoms remain unclear. In this study, we established a mouse model fed diets with three different dose gradients of vitamin D3 (0, 500, and 2000 IU/kg·day) from postnatal day 21 (P21) to 14 weeks of age. Striatal tissues from mice with gradient vitamin D3 intake were subjected to reduced representation bisulfite sequencing (RRBS), RNA-sequencing, and neurotransmitter profiling by liquid chromatography-mass spectrometry (LC-MS). Our findings indicate that vitamin D supplementation since childhood influenced the overall landscape of DNA methylations and the expression of many genes involved in critical neurological functions in a dose-dependent manner. Additionally, our data demonstrate how vitamin D modulated neuropeptide signaling pathways, as well as cholinergic and dopaminergic synapses in the striatum, through an orchestrated mechanism involving epigenetic and transcriptional regulations. Furthermore, we observed a synergistic effect of vitamin D on dopamine release following acute methylphenidate injection into our mouse model. In summary, this study provides mechanistic insights into how dietary vitamin D supplementation since childhood can modulate specific signal transductions among striatal cells, underscoring the importance of vitamin D supplementation for ADHD management.

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The unfolding dynamics of ubiquitin were studied using a combination of x-ray solution scattering (XSS) and molecular dynamics (MD) simulations. The kinetic analysis of the XSS ubiquitin signals showed that the protein unfolds through a two-state process, independent of the presence of destabilizing salts. In order to characterize the ensemble of unfolded states in atomic detail, the experimental XSS results were used as a constraint in the MD simulations through the incorporation of x-ray scattering derived potential to drive the folded ubiquitin structure toward sampling unfolded states consistent with the XSS signals. We detail how biased MD simulations provide insight into unfolded states that are otherwise difficult to resolve and underscore how experimental XSS data can be combined with MD to efficiently sample structures away from the native state. Our results indicate that ubiquitin samples unfolded in states with a high degree of loss in secondary structure yet without a collapse to a molten globule or fully solvated extended chain. Finally, we propose how using biased-MD can significantly decrease the computational time and resources required to sample experimentally relevant nonequilibrium states.

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Two-dimensional (2D) and three-dimensional (3D) perovskite heterostructures have played a key role in advancing the performance of perovskite solar cells1,2. However, the migration of cations between 2D and 3D layers results in the disruption of octahedral networks, leading to degradation in performance over time3,4. We hypothesized that perovskitoids, with robust organic-inorganic networks enabled by edge- and face-sharing, could impede ion migration. We explored a set of perovskitoids of varying dimensionality and found that cation migration within perovskitoid-perovskite heterostructures was suppressed compared with the 2D-3D perovskite case. Increasing the dimensionality of perovskitoids improves charge transport when they are interfaced with 3D perovskite surfaces-this is the result of enhanced octahedral connectivity and out-of-plane orientation. The 2D perovskitoid (A6BfP)8Pb7I22 (A6BfP: N-aminohexyl-benz[f]-phthalimide) provides efficient passivation of perovskite surfaces and enables uniform large-area perovskite films. Devices based on perovskitoid-perovskite heterostructures achieve a certified quasi-steady-state power conversion efficiency of 24.6% for centimetre-area perovskite solar cells. We removed the fragile hole transport layers and showed stable operation of the underlying perovskitoid-perovskite heterostructure at 85 °C for 1,250 h for encapsulated large-area devices in ambient air.

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Objective: To discuss the efficacy and safety of the dual immunotherapy of nivolumab plus ipilimumab in patients with advanced non-small cell lung cancer (NSCLC) who are double negative for driver gene and programmed death-ligand 1 (PD-L1) expression. Methods: We conducted a retrospective collection of clinical data for 61 patients with advanced NSCLC who were negative for both driver genes and PD-L1 and received dual immunotherapy with nivolumab plus ipilimumab at the First Affiliated Hospital of Guangzhou Medical University from January 2019 to June 2023. Based on treatment conditions, patients were divided into first-line and non-first-line dual immunotherapy groups. Patients were followed up monthly, with the follow-up period ending on October 1, 2023. The efficacy was evaluated using Solid Tumor Response Evaluation Criteria, and adverse reactions were assessed according to the Common Terminology Criteria for Adverse Events developed by the National Cancer Institute in the United States. Survival curves were plotted using the Kaplan-Meier method, and the log-rank test was used to compare the differences in progression-free survival (PFS) and overall survival (OS) between first-line and non-first-line dual immunotherapy patients. The influence factors of PFS were analyzed using a multivariate Cox proportional hazards regression model. Results: Among the 61 NSCLC patients, 49 were male (80.3%), with an age range of 23-88 years [(65.3±7.4) years]. There were 14 cases (23.0%) classified as stage ⅢC and 47 cases (77.0%) classified as stage Ⅳ according to TNM staging. Forty cases (65.6%) received non-first-line treatment. The objective response rate (ORR) was 24.6% (15/61), and the disease control rate (DCR) was 52.5% (32/61). All 61 patients were followed up, with a median follow-up time of 17.8 months. The median PFS was 6.0 months (95%CI: 5.5-6.4 months), and the median OS was 17.0 months (95%CI: 14.8-19.2 months). For patients receiving first-line dual immunotherapy, the median PFS was longer than for those receiving non-first-line dual immunotherapy [7.0 months (95%CI: 6.0-7.9 months) vs 4.0 months (95%CI: 3.3-4.6 months), P<0.001]; similarly, the median OS for patients receiving first-line dual immunotherapy was longer than for those receiving non-first-line dual immunotherapy [19.0 months (95%CI: 18.1-19.9 months) vs 13.0 months (95%CI: 10.8-15.1 months), P<0.001]. Multivariate Cox risk regression model analysis showed that distant tumor metastasis (HR=1.414, 95%CI: 1.253-1.725), non-first-line dual immunotherapy (HR=1.412, 95%CI: 1.184-1.652), and tumor mutation burden<10 mut/Mb (HR=1.328, 95%CI: 1.151-1.546) were risk factors for PFS, while non-squamous carcinoma (HR=0.917, 95%CI: 0.823-0.984) was a protective factor for PFS. Immune-related adverse reactions occurred in 41 cases (67.2%), including 21 cases (32.8%) of grade 3-4 adverse reactions. Eight cases (13.1%) discontinued treatment, and there were no deaths. Conclusions: Dual immunotherapy with nivolumab plus ipilimumab can be a treatment option for driver gene and PD-L1 double-negative advanced NSCLC. Distant tumor metastasis, non-first-line dual immunotherapy, and tumor mutation burden<10 mut/Mb are risk factors affecting patients' PFS, while non-squamous cell carcinoma is a protective factor affecting patients' PFS.

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Copper(I) bis-diimine complexes have played important roles in light-activated processes that can lead to their potential applications in photocatalysis and chemical sensing. Their metal-to-ligand charge-transfer (MLCT) excited-state properties are tunable by various structural factors. Dimeric Cu(I) complexes with connecting diimine derivative ligands offer another structural tuning platform for the excited-state properties. Here, we investigate excited-state properties in two covalently connected dimeric Cu(I)'s with varying structural constraints exerted by the number of carbons in the polyethylene bridge (C0 and C4) connecting the two copper(I) diimine moieties. An interesting feature of Cu(I) diimine complexes is their ability to flatten following a photoinduced structural change. Herein, we observe larger structural constraints and more structural rearrangement required upon excitation of the longer bridged complex C4 to achieve a conformation toward a more flattened tetrahedral coordination geometry compared to the shorter bridged C0. Vibrational wavepacket analysis of these complexes further supports the effect of these structural constraints where we observe a more rapid dephasing of the C0 complex, as opposed to the C4 complex, despite similar normal mode vibrations. The experimental results were supplemented by TDDFT calculations. The studies provide insight into using metal-metal interactions through constraints to tune excited-state dynamics and pathways.

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BACKGROUND AND AIM: Preeclampsia, a pregnancy complication associated with significant maternal and perinatal mortality and morbidity, has been found to be closely linked to dysfunction in the blood coagulation-fibrinolysis system. However, the relationship between hematologic data and severity and onset time of preeclampsia remains unclear. This study aimed to identify specific hematologic parameters in both preeclamptic and normotensive pregnant women and determine their potential significance in the pathogenesis of preeclampsia. MATERIALS AND METHODS: A total of 112 patients with gestational hypertension disease were divided into two groups: early-onset preeclampsia (32 cases) and late-onset preeclampsia (80 cases). A control group of 82 normotensive pregnant women matched for age and parity was also selected. Blood samples were collected from all participants to test for specific hematologic parameters. RESULTS: Mild and severe preeclampsia were associated with lower hemoglobin level (P = 0.01 and P = 0.03, respectively), higher mean platelet volume (P = 0.01 and P = 0.01, respectively) and fibrinogen (P = 0.01 and P = 0.01, respectively), and shorter prothrombin time (P = 0.02 and P = 0.01, respectively) and activated partial thromboplastin time (P = 0.01 and P = 0.02, respectively). CONCLUSION: These findings have provided evidence on the hematologic coagulative actors in the pathogenesis and severity of preeclampsia.

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Semiconductor nanocrystals (NCs) with size-tuned energy gaps present unique and desirable properties for optoelectronic applications. Recent synthetic advancements offer routes to spheroidal CsPbBr3 perovskite NCs in the strong quantum confinement regime with narrow size dispersion. Using tunable femtosecond laser pulses, we examine intraband carrier relaxation using transient absorption spectroscopy and show that, across the transition from weak to strong confinement, hot carrier lifetime increases compared to larger bulk-like particles. However, further increases of confinement subsequently lead to a reduction of the hot carrier lifetime and increase of the non-radiative Auger recombination rate. Finally, we show that hot carrier lifetimes increase as a function of excess energy above the band gap less sensitively under high confinement in comparison to the bulk. Understanding such unique trends is important for maximizing hot carrier lifetimes for use in next-generation hot carrier devices as well as evaluating the transition from weak to strong confinement.

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One of the primary methods for band gap tuning in metal halide perovskites has been halide (I/Br) mixing. Despite widespread usage of this type of chemical substitution in perovskite photovoltaics, there is still little understanding of the structural impacts of halide alloying, with the assumption being the formation of ideal solid solutions. The FASnI3-xBrx (x = 0-3) family of compounds provides the first example where the assumption breaks down, as the composition space is broken into two unique regimes (x = 0-2.9; x = 2.9-3) based on their average structure with the former having a 3D and the latter having an extended 3D (pseudo 0D) structure. Pair distribution function (PDF) analyses further suggest a dynamic 5s2 lone pair expression resulting in increasing levels of off-centering of the central Sn as the Br concentration is increased. These antiferroelectric distortions indicate that even the x = 0-2.9 phase space behaves as a nonideal solid-solution on a more local scale. Solid-state NMR confirms the difference in local structure yielding greater insight into the chemical nature and local distributions of the FA+ cation. In contrast to the FAPbI3-xBrx series, a drastic photoluminescence (PL) quenching is observed with x ≥ 1.9 compounds having no observable PL. Our detailed studies attribute this quenching to structural transitions induced by the distortions of the [SnBr6] octahedra in response to stereochemically expressed lone pairs of electrons. This is confirmed through density functional theory, having a direct impact on the electronic structure.

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Chemical transformations in charge transfer states result from the interplay between electronic dynamics and nuclear reorganization along excited-state trajectories. Here, we investigate the ultrafast structural dynamics following photoinduced electron transfer from the metal-metal-to-ligand charge transfer state of an electron donor, a Pt dimer complex, to a covalently linked electron acceptor group using ultrafast time-resolved wide-angle X-ray scattering and optical transient absorption spectroscopy methods to disentangle the interdependence of the excited-state electronic and nuclear dynamics. Following photoexcitation, Pt-Pt bond formation and contraction takes up to 1 ps, much slower than the corresponding process in analogous complexes without electron acceptor groups. Because the Pt-Pt distance change is slow with respect to excited-state electron transfer, it can affect the rate of electron transfer. These results have potential impacts on controlling electron transfer rates via structural alterations to the electron donor group, tuning the charge transfer driving force.

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PURPOSE: We aim to detect serum DKK1 level of pediatric patients with OI and to analyze its relationship with the genotype and phenotype of OI patients. METHODS: A cohort of pediatric OI patients and age-matched healthy children were enrolled. Serum levels of DKK1 and bone turnover biomarkers were measured by enzyme-linked immunosorbent assay. Bone mineral density (BMD) was measured by Dual-energy X-ray absorptiometry. Pathogenic mutations of OI were detected by next-generation sequencing and confirmed by Sanger sequencing. RESULTS: A total of 62 OI children with mean age of 9.50 (4.86, 12.00) years and 29 healthy children were included in this study. The serum DKK1 concentration in OI children was significantly higher than that in healthy children [5.20 (4.54, 6.32) and 4.08 (3.59, 4.92) ng/mL, P < 0.001]. The serum DKK1 concentration in OI children was negatively correlated with height (r = - 0.282), height Z score (r = - 0.292), ALP concentration (r = - 0.304), lumbar BMD (r = - 0.276), BMD Z score of the lumbar spine and femoral neck (r = - 0.32; r = - 0.27) (all P < 0.05). No significant difference in serum DKK1 concentration was found between OI patients with and without vertebral compression fractures. In patients with spinal deformity (22/62), serum DKK1 concentration was positively correlated with SDI (r = 0.480, P < 0.05). No significant correlation was observed between serum DKK1 concentration and the annual incidence of peripheral fractures, genotype and types of collagen changes in OI children. CONCLUSION: The serum DKK1 level was not only significantly elevated in OI children, but also closely correlated to their skeletal phenotype, suggesting that DKK1 may become a new biomarker and a potential therapeutic target of OI.

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Objective: To evaluate the efficacy of neoadjuvant chemoimmunotherapy (NACI) combined with transoral robotic surgery (TORS) in the treatment of locally advanced oropharyngeal squamous cell carcinoma (OPSCC). Methods: This was a retrospective study of 15 patients with locally advanced OPSCC who underwent TORS after neoadjuvant therapy (NAT) at the Department of Otolaryngology-Head and Neck Surgery of Sun Yat-sen Memorial Hospital of Sun Yat-sen University from April 2019 to February 2023. There were 12 males and 3 females, aged 31 to 74 years. Twelve cases were tonsil cancer, and 3 cases were tongue base cancer. There were 11 cases in stage Ⅲ and 4 cases in stage Ⅳ. Two patients received neoadjuvant chemotherapy and 13 patients received NACI, with 2 to 3 cycles, and all patients underwent TORS after multidisciplinary team consultation. The clinicopathological characteristics, surgical outcomes, and oncological results were summarized. Results: All surgeries were successfully completed with negative surgical margins, and no case was required conversion surgery. All patients were fed via nasogastric tubes postoperatively, with a median gastric tube stay of 7 days (range: 2-60 days). No tracheotomy was applied. There were no major complications such as postoperative bleeding. Pathological complete response (pCR) was found in 10 cases (76.9%) among the 13 patients with NACI. The follow-up time was 21 months (range: 10-47 months), and there was no death or distant metastasis. One patient with rT0N3M0 tonsil cancer had local recurrence 5 months after surgery. The 2-year overall survival and 2-year disease-free survival were respectively 100.0% and 93.3% in the 15 patients. Conclusion: NACI combined with TORS provides a safe, effective and minimally invasive treatment for patients with locally advanced oropharyngeal squamous cell carcinoma.

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Utilization of renewable energies for catalytically generating value-added chemicals is highly desirable in this era of rising energy demands and climate change impacts. Artificial photosynthetic systems or photocatalysts utilize light to convert abundant CO2, H2O, and O2 to fuels, such as carbohydrates and hydrogen, thus converting light energy to storable chemical resources. The emergence of intense X-ray pulses from synchrotrons, ultrafast X-ray pulses from X-ray free electron lasers, and table-top laser-driven sources over the past decades opens new frontiers in deciphering photoinduced catalytic reaction mechanisms on the multiple temporal and spatial scales. Operando X-ray spectroscopic methods offer a new set of electronic transitions in probing the oxidation states, coordinating geometry, and spin states of the metal catalytic center and photosensitizers with unprecedented energy and time resolution. Operando X-ray scattering methods enable previously elusive reaction steps to be characterized on different length scales and time scales. The methodological progress and their application examples collected in this review will offer a glimpse into the accomplishments and current state in deciphering reaction mechanisms for both natural and synthetic systems. Looking forward, there are still many challenges and opportunities at the frontier of catalytic research that will require further advancement of the characterization techniques.

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Solar fuels catalysis is a promising route to efficiently harvesting, storing, and utilizing abundant solar energy. To achieve this promise, however, molecular systems must be designed with sustainable components that can balance numerous photophysical and chemical processes. To that end, we report on the structural and photophysical characterization of a series of Cu(I)-anthraquinone-based electron donor-acceptor dyads. The dyads utilized a heteroleptic Cu(I) bis-diimine architecture with a copper(I) bis-phenanthroline chromophore donor and anthraquinone electron acceptor. We characterized the structures of the complexes using x-ray crystallography and density functional theory calculations and the photophysical properties via resonance Raman and optical transient absorption spectroscopy. The calculations and resonance Raman spectroscopy revealed that excitation of the Cu(I) metal-to-ligand charge-transfer (MLCT) transition transfers the electron to a delocalized ligand orbital. The optical transient absorption spectroscopy demonstrated that each dyad formed the oxidized copper-reduced anthraquinone charge-separated state. Unlike most Cu(I) bis-phenanthroline complexes where increasingly bulky substituents on the phenanthroline ligands lead to longer MLCT excited-state lifetimes, here, we observe a decrease in the long-lived charge-separated state lifetime with increasing steric bulk. The charge-separated state lifetimes were best explained in the context of electron-transfer theory rather than with the energy gap law, which is typical for MLCT excited states, despite the complete conjugation between the phenanthroline and anthraquinone moieties.

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Disrupted sleep has a profound adverse impact on lives of Parkinson's disease (PD) patients and their caregivers. Sleep disturbances are exceedingly common in PD, with substantial heterogeneity in type, timing, and severity. Among the most common sleep-related symptoms reported by PD patients are insomnia, excessive daytime sleepiness, and sleep fragmentation, characterized by interruptions and decreased continuity of sleep. Alterations in brain wave activity, as measured on the electroencephalogram (EEG), also occur in PD, with changes in the pattern and relative contributions of different frequency bands of the EEG spectrum to overall EEG activity in different vigilance states consistently observed. The mechanisms underlying these PD-associated sleep-wake abnormalities are poorly understood, and they are ineffectively treated by conventional PD therapies. To help fill this gap in knowledge, a new progressive model of PD - the MCI-Park mouse - was studied. Near the transition to the parkinsonian state, these mice exhibited significantly altered sleep-wake regulation, including increased wakefulness, decreased non-rapid eye movement (NREM) sleep, increased sleep fragmentation, reduced rapid eye movement (REM) sleep, and altered EEG activity patterns. These sleep-wake abnormalities resemble those identified in PD patients. Thus, this model may help elucidate the circuit mechanisms underlying sleep disruption in PD and identify targets for novel therapeutic approaches.