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BACKGROUND: In the initial analysis of a pivotal phase 2 single-arm study (NCT03861156), befotertinib (D-0316) showed clinical benefit with a manageable safety profile in pretreated patients with EGFR T790M mutated non-small cell lung cancer (NSCLC), including those with brain metastases. METHODS: Eligible patients received oral befotertinib of 50 mg (cohort A) or 75-100 mg (cohort B) once daily until disease progression, withdrawal of informed consent, or death. The primary endpoint for the initial analysis was objective response rate (ORR) assessed by an independent review committee. OS and safety were secondary endpoints. Herein, we present the final OS and safety data. RESULTS: A total of 176 patients in cohort A and 290 patients in cohort B were finally enrolled. At data cutoff (May 31, 2023), the median duration of follow-up was 47.9 months (95 % CI: 47.1-48.3) in cohort A and 36.7 months (35.9-37.9) in cohort B. The median OS was 23.9 months (95 % CI: 21.1-27.2) in cohort A and 31.5 months (26.8-35.3) in cohort B. The median OS for patients with and without brain metastasis in cohort A was 18.6 months (95 % CI: 14.9-26.3) and 26.4 months (95 % CI: 23.0-29.0), respectively. In cohort B, these data was 23.0 months (95 % CI: 18.6-29.1) and 35.5 months (95 % CI: 29.3-NE), respectively. The safety profile of befotertinib remained consistent with previous data. Grade 3 or higher treatment-emergent adverse events were 38.1 % in the cohort A and 50.3 % in the cohort B, and 22.2 % and 31.7 % were related to the study drug. CONCLUSION: Befotertinib demonstrated a more profound OS benefit compared to other 3rd-generation EGFR TKI, despite that cross trial data comparison should be interpreted with caution. The safety profile was manageable and consistent with previously report data in pretreated patients with confirmed T790M mutation-positive NSCLC.

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BACKGROUND: The prevalence of COVID-19 as the primary diagnosis among hospitalized patients with myocardial injury has increased during the pandemic and targeting elevated oxidant stress and inflammatory biomarkers may offer a potential role for novel therapies to improve outcomes. METHODS: At a single VA Medical Center from January 1 through December 31, 2021, troponin assays from patients being evaluated in the Emergency Room for consideration of admission were analyzed and peak levels from each patient were considered abnormal if exceeding the Upper Reference Limit (URL). Among admitted patients with an elevated troponin level, ICD-10 diagnoses were categorized, biomarker elevations were recorded, and independent predictors of death in patients with COVID-19 were determined at a median of 6-months following admission. RESULTS: Of 998 patients, 399 (40 %) had a negative troponin and were not included in the analysis. Additional patients with an elevated troponin were also excluded, either because they were not admitted (n = 68) or had a final diagnosis of Type 1 MI (n = 117). Of the remaining 414 patients with an elevated peak troponin, COVID-19 was the primary diagnosis in 43 patients (10 %) and was the 4th most common diagnosis of patients admitted with myocardial injury behind congestive heart failure, sepsis, and COPD or pneumonia. At a median of 6-months following admission, 18 (42 %) of the COVID-19 patients had died and independent predictors of death (Odd Ratio: Confidence Intervals) were age (1.18: 1.06‒1.37), Troponin level (Log 10 transformed) (16.54: 2.30‒266.65) and C-Reactive Protein (CRP) (1.30: 1.10‒1.65). CONCLUSIONS: Newly diagnosed COVID-19 during the pandemic was a common cause of elevated troponin in hospitalized patients without a Type 1 MI. Age, peak troponin level and peak CRP level were independent predictors of poor outcomes and suggest a need to target these cardiac biomarkers, potentially with novel antioxidant or anti-inflammatory therapies.

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Extracellular matrix (ECM) is essential for tissue development, providing structural support and a microenvironment that is necessary for cells. As tissue engineering advances, there is a growing demand for ECM mimics. Polycaprolactone (PCL) is a commonly used synthetic polymer for ECM mimic materials. However, its biologically inactive surface limits its direct application in tissue engineering. Our study aimed to improve the biocompatibility of PCL by incorporating hemoglobin nanofibrils (HbFs) into PCL using an electrospinning technique. HbFs were formed from bovine hemoglobin (Hb) extracted from industrial byproducts and designed to offer PCL an improved cell adhesion property. The fabricated HbFs@PCL electrospun scaffold exhibits improved fibroblast adherence, proliferation, and deeper fibroblast infiltration into the scaffold compared with the pure PCL scaffold, indicating its potential to be an ECM mimic. This study represents the pioneering utilization of Hb-sourced nanofibrils in the electrospun PCL scaffolds for tissue engineering applications.

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Bus driver anger due to passenger misbehavior may lead to serious bus accidents, yet there are no mature tools available to capture bus driver reactions during driver-passenger conflicts. The bus driver anger scale (BDAS) and the bus driver anger expression inventory (BDAX) were developed to measure the anger levels and expressions of drivers in such conflicts. A bus driver anger model was developed based on 400 questionnaires in Changsha, China. The findings indicate that drivers are most likely to be angered by passenger violations and quarrels among passengers. Drivers irritated by passenger irregularities tend to employ personal aggressive expression or adaptive/constructive expression. Disputes among passengers may lead drivers to resort to unreasonable methods of venting their emotions. Moreover, passengers' rude behaviors can trigger bus drivers' aggressive personal expressions. Therefore, it is necessary to establish passenger regulations and encourage drivers to express their anger reasonably in driver-passenger conflicts.

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The CRISPR/Cas13 nucleases have been widely documented for nucleic acid detection. Understanding the intricacies of CRISPR/Cas13's reaction components is pivotal for harnessing its full potential for biosensing applications. Herein, we report on the influence of CRISPR/Cas13a reaction components on its trans-cleavage activity and the development of an on-chip total internal reflection fluorescence microscopy (TIRFM)-powered RNA sensing system. We used SARS-CoV-2 synthetic RNA and pseudovirus as a model system. Our results show that optimizing Mg2+ concentration, reporter length, and crRNA combination significantly improves the detection sensitivity. Under optimized conditions, we detected 100 fM unamplified SARS-CoV-2 synthetic RNA using a microtiter plate reader. To further improve sensitivity and provide a new amplification-free RNA sensing toolbox, we developed a TIRFM-based amplification-free RNA sensing system. We were able to detect RNA down to 100 aM. Furthermore, the TIRM-based detection system developed in this study is 1000-fold more sensitive than the off-coverslip assay. The possible clinical applicability of the system was demonstrated by detecting SARS-CoV-2 pseudovirus RNA. Our proposed sensing system has the potential to detect any target RNA with slight modifications to the existing setup, providing a universal RNA detection platform.

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PURPOSE: To reduce the ringing artifacts of the motion-resolved images in free-breathing dynamic pulmonary MRI. METHODS: A golden-step based interleaving (GSI) technique was proposed to reduce ringing artifacts induced by diaphragm drifting. The pulmonary MRI data were acquired using a superior-inferior navigated 3D radial UTE sequence in an interleaved manner during free breathing. Successive interleaves were acquired in an incoherent fashion along the polar direction. Four-dimensional images were reconstructed from the motion-resolved k-space data obtained by retrospectively binning. The reconstruction algorithms included standard nonuniform fast Fourier transform (NUFFT), Voronoi-density-compensated NUFFT, extra-dimensional UTE, and motion-state weighted motion-compensation reconstruction. The proposed interleaving technique was compared with a conventional sequential interleaving (SeqI) technique on a phantom and eight subjects. RESULTS: The quantified ringing artifacts level in the motion-resolved image is positively correlated with the quantified nonuniformity level of the corresponding k-space. The nonuniformity levels of the end-expiratory and end-inspiratory k-space binned from GSI data (0.34 ± 0.07, 0.33 ± 0.05) are significantly lower with statistical significance (p < 0.05) than that binned from SeqI data (0.44 ± 0.11, 0.42 ± 0.12). Ringing artifacts are substantially reduced in the dynamic images of eight subjects acquired using the proposed technique in comparison with that acquired using the conventional SeqI technique. CONCLUSION: Ringing artifacts in the motion-resolved images induced by diaphragm drifting can be reduced using the proposed GSI technique for free-breathing dynamic pulmonary MRI. This technique has the potential to reduce ringing artifacts in free-breathing liver and kidney MRI based on full-echo interleaved 3D radial acquisition.

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Background: Laryngeal squamous cell carcinoma (LSCC) prognosis has not improved significantly in the past few decades, and more effective treatments are needed to be explored. Ferroptosis is a newly discovered kind of regulated cell death in recent years, which is related to tumor immunity and can used to treat tumors. Therefore, the prognostic value of ferroptosis-related genes in laryngeal cancer needs further clarification. Methods: In this study, the mRNA expression profile data of LSCC were downloaded from the public database. After identifying ferroptosis-related differentially expressed genes (FDGs), we explored the role of these genes through functional enrichment analysis. FDGs with prognostic significance were identified by univariate Cox and least absolute shrinkage and selection operator (LASSO) regression analyses. By calculating the risk score, we constructed a prognostic model. Kaplan-Meier (K-M) analysis, the receiver operating characteristic (ROC) curves, and the nomogram were utilized to investigate this model. Public databases and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to verify the expression of model genes. Results: The model consisting of four FDGs was acknowledged to be a self-determining predictor of prognosis. The K-M survival curves and the ROC curves confirmed the model's predictive ability. The C index (0.805) indicates that the nomogram has a good predictive ability. In vitro studies have confirmed the differential expression of the four FDGs. Conclusions: We identified a novel ferroptosis-related gene signature for predicting prognosis in LSCC.

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Introduction: Conducting Visual Display Terminal (VDT) visual search tasks under time constraint has broad applications in fields such as security checks, medical diagnostics, and rescue operations. While excessive time pressure can impair performance, moderate time pressure can motivate individuals to complete tasks and increase productivity. Investigating the positive impact of time pressure on visual search tasks has become a crucial area of study. Clock timing plays a vital role in the visual interface, influencing the perception of time pressure and impacting visual search performance. However, existing research has paid little attention to the induction of time pressure and the impact of clock timing in VDT visual interfaces on visual search performance. Hence, the objective of this study is to investigate the impact of clock timing on VDT visual search performance under time constraint. Methods: The content of the experimental tasks was determined through a pilot experiment. The formal experiment was conducted in two phases over six sessions. Participants were tasked with locating the letter "E" embedded within the distractor letter "F," displayed with a clock area above the interface. The first phase of experiments included conditions of no clock, 4-min clock timing, and 4-min countdown clock timing. In the second phase of the experiment, the clock display method was a countdown clock, with three experiments conducted featuring long time, medium time, and short time. Search speed and accuracy were used as primary performance evaluation metrics to examine the impact of clock timing methods and duration on visual search performance. Twenty-one undergraduate students participated in the formal experiment. Results: In the first phase of experiments, participants demonstrated significantly faster reaction times (RTs) in tasks where a clock display was present compared to tasks without (ANOVA, F(2, 60) = 4.588, P = 0.014). However, there were no significant differences in accuracy rates across different timing conditions (ANOVA, F(2, 60) = 0.146, P = 0.865), and no significant correlation between RTs and accuracy was found (Kendall's R = 0.11, P = 0.914). During the second phase, RTs decreased significantly as time constraints became more stringent (ANOVA, F(2, 60) = 7.564, P < 0.05). Conversely, accuracy rates decreased significantly under shorter time constraints (ANOVA, F(2, 60) = 4.315, P < 0.05), with a negative correlation observed between RTs and accuracy (Kendall's R = 0.220, P < 0.01). Discussion: Compared to conditions without clock displays, having clock displays significantly improved the speed of the visual search task, although the difference in accuracy was not statistically significant. In the context of shorter clock countdown limits, Shorter timing constraints resulted in faster search speeds but also led to reduced accuracy and increased fatigue. Overall, a correlation exists between search speed and accuracy in visual tasks, where higher speed often correlates with lower accuracy. These findings provide valuable insights into clock timing design for visual search interfaces under time pressure.

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Gamma knife radiosurgery (GKRS) is recommended as the first-line treatment for brain metastases of lung adenocarcinoma (LUAD) in many guidelines, but its specific mechanism is unclear. We aimed to study the changes in the proteome of brain metastases of LUAD in response to the hyperacute phase of GKRS and further explore the mechanism of differentially expressed proteins (DEPs). Cancer tissues were collected from a clinical trial for neoadjuvant stereotactic radiosurgery before surgical resection of large brain metastases (ChiCTR2000038995). Five brain metastasis tissues of LUAD were collected within 24 h after GKRS. Five brain metastasis tissues without radiotherapy were collected as control samples. Proteomics analysis showed that 163 proteins were upregulated and 25 proteins were downregulated. GO and KEGG enrichment analyses showed that the DEPs were closely related to ribosomes. Fifty-three of 70 ribosomal proteins were significantly overexpressed, while none of them were underexpressed. The risk score constructed from 7 upregulated ribosomal proteins (RPL4, RPS19, RPS16, RPLP0, RPS2, RPS26 and RPS25) was an independent risk factor for the survival time of LUAD patients. Overexpression of ribosomal proteins may represent a desperate response to lethal radiotherapy. We propose that targeted inhibition of these ribosomal proteins may enhance the efficacy of GKRS.

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The orientation and rearrangement of water on a gold electrode significantly influences its physicochemical heterogeneous performance. Despite numerous experimental and theoretical studies aimed at uncovering the structural characteristics of interfacial water, the orientational behavior resulting from electrode-induced rearrangements remains a subject of ongoing debate. Here, we employed molecular dynamics simulations to investigate the adaptive structure and dynamics properties of interfacial water on Au(111) and Au(100) surfaces by considering a polarizable model for Au atoms in comparison with the non-polarizable model. Compared to the nonpolarizable systems, the polarization effect can enhance the interaction between water molecules and the gold surface. Unexpectedly, the rotational dynamics directly associated with the orientational behavior of water adjacent to the gold surface is accelerated, thereby reducing the hydrogen bond lifetime. The underlying mechanism for this anomalous phenomenon originates from the polarization effect, which induces the attraction of the positive hydrogen atoms to the surface by the negative image charge. This leads to a change in orientation that disrupts the hydrogen bonds in the first water layer and subsequently accelerates reorientation dynamics of water molecules adjacent to the gold surface. These results shed light on the intricate interplay between polarization effects and water molecule dynamics on metal surfaces, establishing the foundation for the rational regulation of the orientation of interfacial water.

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BACKGROUND: The sustained effectiveness of anti-programmed cell death protein-1/programmed death-ligand 1 treatment is limited to a subgroup of patients with advanced nasopharyngeal carcinoma (NPC), and the specific biomarker determining the response to immunotherapy in NPC remains uncertain. METHODS: We assessed the associations between pre-immunotherapy and post-immunotherapy serum lipoproteins and survival in a training cohort (N=160) and corroborated these findings in a validation cohort (N=100). Animal studies were performed to explore the underlying mechanisms. Additionally, the relationship between high-density lipoprotein-cholesterol (HDL-C) levels and M1/M2-like macrophages, as well as activated CD8+T cells in tumor tissues from patients with NPC who received immunotherapy, was investigated. RESULTS: The lipoproteins cholesterol, HDL-C, low-density lipoprotein-cholesterol, triglycerides, apolipoprotein A-1 (ApoA1), and apolipoprotein B, were significantly altered after immunotherapy. Patients with higher baseline HDL-C or ApoA1, or those with increased HDL-C or ApoA1 after immunotherapy had longer progression-free survival, a finding verified in the validation cohort (p<0.05). Multivariate analysis revealed that baseline HDL-C and elevated HDL-C post-immunotherapy were independent predictors of superior PFS (p<0.05). Furthermore, we discovered that L-4F, an ApoA1 mimetic, could inhibit tumor growth in NPC xenografts. This effect was associated with L-4F's ability to polarize M2-like macrophages towards an M1-like phenotype via the activation of mitogen-activated protein kinase (MAPK) p38 and nuclear factor-κB (NF-κB) p65, thereby alleviating immunosuppression in the tumor microenvironment. Importantly, in patients with NPC with high plasma HDL-C levels, the number of M2-like macrophages was significantly decreased, while M1-like macrophages and activated CD8+T cells were notably increased in those with high HDL-C levels. CONCLUSION: Higher baseline HDL-C levels or an increase in HDL-C post-immunotherapy can enhance immunotherapeutic responses in patients with NPC by reprogramming M2-like macrophages towards the M1 phenotype. This suggests a potential role for prospectively exploring ApoA1 mimetics as adjuvant agents in combination with immunotherapy.

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Synaptic transistors have been proposed to implement neuron activation functions of neural networks (NNs). While promising to enable compact, fast, inexpensive, and energy-efficient dedicated NN circuits, they also have limitations compared to digital NNs (realized as codes for digital processors), including shape choices of the activation function using particular types of transistor implementation, and instabilities due to noise and other factors present in analog circuits. We present a computational study of the effects of these factors on NN performance and find that, while accuracy competitive with traditional NNs can be realized for many applications, there is high sensitivity to the instability in the shape of the activation function, suggesting that, when highly accurate NNs are required, high-precision circuitry should be developed beyond what has been reported for synaptic transistors to date.

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OBJECTIVE: To evaluate the incidence and the independent risk factors of SRS-related epilepsy in patients with supratentorial brain metastases (st-BMs), providing evidences for prevention or reduction secondary epilepsy after SRS. METHODS: Patients with st-BMs from four gamma knife centers who developed secondary epilepsy after SRS were retrospectively studied between January 1, 2017 and June 31, 2023. The incidence and clinical characteristics of the patients with secondary epilepsy were analyzed. The predictive role of baseline clinical-demographic variables was evaluated according to univariate and multivariate logistic regression model. The impact of secondary epilepsy on patients' OS was evaluated as well by log-rank test. RESULTS: 11.3 % (126/1120) of the patients with totally 158 st-BMs experienced secondary epilepsy after SRS in median 21 days. 61.9 % (78/126) of the patients experienced simple partial seizures. 91.3 % (115/126) patients achieved good seizure control after received 1-2 kinds of AEDs for median 90 days, while 7.1 % (9/126) of the patients suffered from refractory epilepsy. Patients had higher risk of secondary epilepsy if the tumor located in cortex and/or hippocampus, peri-tumor edema larger than 20.3 cm3 before SRS, had epilepsy history, and failed to receive bevacizumab prior to SRS. There was no difference in the OS of patients who experience secondary epilepsy or not after SRS. CONCLUSIONS: The incidence of SRS-related secondary epilepsy is 11.3 % in patients with st-BMs in this retrospective study. The risk of secondary epilepsy is higher in patients with st-BM located in cortex and/or hippocampus area, peri-tumor edema larger than 20.3 cm3 before SRS, and epilepsy history. Bevacizumab is suggested prior to SRS therapy, as it could be used for the control of peri-tumor edema and SRS-related damage, hence reduce the risk of secondary epilepsy. However, whether or not patients suffered from secondary epilepsy after SRS does not affect their OS.

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Distributed energy systems encompass a diverse range of generation and storage solutions on the user side, where decentralized management schemes to maximize the overall social welfare are preferred considering their dispersed ownership. However, either security or privacy problems occur in recently proposed schemes. Here we report a decentralized framework leveraging the strengths of blockchain and parallelizable mathematical algorithms to overcome these potential drawbacks. The system owners bid cost functions and operating constraints through masked but coupled management subproblems, which are redistributed by the blockchain to be verifiably solved by competent peers. Such processes are iteratively executed as decisions and shadow prices are exchanged among participants, until an equilibrium is reached. The interactive framework ensures decentralized, privacy-preserving, and secure management of multiple energy sources, and reduces the total cost by 3.0 ~ 7.5% in the test system. Our results benefit the energy prosumers and promote a more active and competitive power grid.

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BACKGROUND: Sepsis, characterized by dysregulated host responses to infection, remains a critical global health concern, with high morbidity and mortality rates. The gastrointestinal tract assumes a pivotal role in sepsis due to its dual functionality as a protective barrier against injurious agents and as a regulator of motility. Dexmedetomidine, an α2-adrenergic agonist commonly employed in critical care settings, exhibits promise in influencing the maintenance of intestinal barrier integrity during sepsis. However, its impact on intestinal motility, a crucial component of intestinal function, remains incompletely understood. METHODS: In this study, we investigated dexmedetomidine's multifaceted effects on intestinal barrier function and motility during sepsis using both in vitro and in vivo models. Sepsis was induced in Sprague-Dawley rats via cecal ligation and puncture. Rats were treated with dexmedetomidine post-cecal ligation and puncture, and various parameters were assessed to elucidate dexmedetomidine's impact. RESULTS: Our findings revealed a dichotomous influence of dexmedetomidine on intestinal physiology. In septic rats, dexmedetomidine administration resulted in improved intestinal barrier integrity, as evidenced by reduced mucosal hyper-permeability and morphological alterations. However, a contrasting effect was observed on intestinal motility, as dexmedetomidine treatment inhibited both the frequency and amplitude of contractions in isolated intestinal strips and decreased the distance of ink migration in vivo. Additionally, dexmedetomidine suppressed the secretion of pro-motility hormones while having no influence on hormones that inhibit intestinal peristalsis. CONCLUSION: The study revealed that during sepsis, dexmedetomidine exhibited protective effects on barrier integrity, although concurrently it hindered intestinal motility, partly attributed to its modulation of pro-motility hormone secretion. These findings underscore the necessity of a comprehensive understanding of dexmedetomidine's impact on multiple facets of gastrointestinal physiology in sepsis management, offering potential implications for therapeutic strategies and patient care.

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BACKGROUND: Dysregulated metabolism of bioactive sphingolipids, including ceramides and sphingosine-1-phosphate, has been implicated in cardiovascular disease, although the specific species, disease contexts, and cellular roles are not completely understood. Sphingolipids are produced by the serine palmitoyltransferase enzyme, canonically composed of 2 subunits, SPTLC1 (serine palmitoyltransferase long chain base subunit 1) and SPTLC2 (serine palmitoyltransferase long chain base subunit 2). Noncanonical sphingolipids are produced by a more recently described subunit, SPTLC3 (serine palmitoyltransferase long chain base subunit 3). METHODS: The noncanonical (d16) and canonical (d18) sphingolipidome profiles in cardiac tissues of patients with end-stage ischemic cardiomyopathy and in mice with ischemic cardiomyopathy were analyzed by targeted lipidomics. Regulation of SPTLC3 by HIF1α under ischemic conditions was determined with chromatin immunoprecipitation. Transcriptomics, lipidomics, metabolomics, echocardiography, mitochondrial electron transport chain, mitochondrial membrane fluidity, and mitochondrial membrane potential were assessed in the cSPTLC3KO transgenic mice we generated. Furthermore, morphological and functional studies were performed on cSPTLC3KO mice subjected to permanent nonreperfused myocardial infarction. RESULTS: Herein, we report that SPTLC3 is induced in both human and mouse models of ischemic cardiomyopathy and leads to production of atypical sphingolipids bearing 16-carbon sphingoid bases, resulting in broad changes in cell sphingolipid composition. This induction is in part attributable to transcriptional regulation by HIF1α under ischemic conditions. Furthermore, cardiomyocyte-specific depletion of SPTLC3 in mice attenuates oxidative stress, fibrosis, and hypertrophy in chronic ischemia, and mice demonstrate improved cardiac function and increased survival along with increased ketone and glucose substrate metabolism utilization. Depletion of SPTLC3 mechanistically alters the membrane environment and subunit composition of mitochondrial complex I of the electron transport chain, decreasing its activity. CONCLUSIONS: Our findings suggest a novel essential role for SPTLC3 in electron transport chain function and a contribution to ischemic injury by regulating complex I activity.

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A diabatic potential energy matrix (DPEM) for the two lowest states of BeH2+ has been constructed using the combined-hyperbolic-inverse-power-representation (CHIPR) method. By imposing symmetry constraints on the coefficients of polynomials, the complete nuclear permutation inversion symmetry is correctly preserved in the CHIPR functional form. The symmetrized CHIPR functional form is then used in the diabatization by ansatz procedure. The ab initio energies are reproduced with satisfactory accuracy. In addition, the CHIPR-based DPEM also reproduces the local topology of a conical intersection. Future work will focus on a complete four-state diabatic representation with emphasis on the long-range interactions and spin-orbit couplings, which will enable accurate quantum scattering calculations for the Be+(2P) + H2 → BeH+(X1Σ+) + H(2S) reaction.

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BACKGROUND: Nutcracker syndrome is a disease characterized by complex symptoms, making its diagnosis challenging and often delayed, often resulting in a painful experience for the patients. OBJECTIVE: This study aimed to investigate the pathogenesis of nutcracker syndrome through the perspective of hemodynamics by simulating blood flow with varying compression degrees of the left renal vein. METHODS: 3D patient-specific vascular models of the abdominal aorta, superior mesenteric artery and left renal vein were constructed based on CT images of patients suspected of having nutcracker syndrome. A hemodynamic simulation was then conducted using computational fluid dynamics to identify the correlation between alterations in hemodynamic parameters and varying degrees of compression. RESULTS: The study indicated the presence of an evident gradient in velocity distribution over the left renal vein with relatively high degrees of stenosis (α ≤ 50°), with maximum velocity in the central region of the stenosis. Additionally, when the compression degree of the left renal vein increases, the pressure distribution of the left renal vein presents an increasing number of gradient layers. Furthermore, the wall shear stress shows a correlation with the variation of blood flow velocity, i.e., the increase of wall shear stress correlates with the acceleration of the blood flow velocity. CONCLUSIONS: Using computational fluid dynamics as a non-invasive instrument to obtain the hemodynamic characteristics of nutcracker syndrome is feasible and could provide insights into the pathological mechanisms of the nutcracker syndrome supporting clinicians in diagnosis.

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Despite 2-staged stereotactic radiosurgery (2-SSRS) has been reported to provide patients with improved survival and limited toxicity, 2-SSRS for brainstem metastases (BSM) larger than 2 cm3 remains challenging. We tried to find out the effectiveness and safety of 2-SSRS plus bevacizumab therapy for BSMs over 2 cm3 and prognostic factors that related to the tumor local control. Patients that received 2-SSRS plus bevacizumab therapy from four gamma knife center were retrospectively studied from Jan 2014 to December 2023. Patients' domestic characteristics and the tumor features were evaluated before and after the treatment. Cox regression model was used to find out prognostic factors for tumor local control. 53 patients with 63 lesions received the therapy. The median peri-tumor edema volume greatly reduced at the end of therapy (P < 0.01), the median tumor volume dramatically reduced (P < 0.01) and patients' KPS score improved significantly (P < 0.05) 3 months after the therapy. Patients' median OS was 12.8 months. The tumor local control rate at 3, 6, and 12 months was 98.4%, 93.4%, and 85.2%. The incidence side effects were mainly oral and nasal hemorrhage (5.7%, 3/53), and radiation necrosis (13.2%, 7/53). Patients with primary lung adenocarcinoma, therapeutic dose over 12 Gy at second-stage SRS, primary peri-tumor edema volume less than 2.3 cm³, primary tumor volume less than 3.7 cm³ would enjoy longer tumor local control. These results suggested that 2-SSRS plus bevacizumab therapy was effective and safe for BSMs over 2 cm3. However, it is important for patients with BSM to receive early diagnosis and treatment to achieve good tumor local control.

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As transient electronics continue to advance, the demand for new materials has given rise to the exploration of conducting polymer (CP)-based electronic materials. The big challenge lies in balancing conductivity while introducing controlled degradable properties into CP-based transient materials. In response to this, we present in this work a concept of using conducting polymers attached to an enzymatically biodegradable biopolymer to create transient polymer electronics materials. Specifically, poly(3-hexyl thiophene) (P3HT) is covalently grafted onto biopolymer gelatin, affording graft copolymer gelatin-graft-poly(3-hexyl thiophene) (termed Gel-g-P3HT). The thin films of Gel-g-P3HT that were produced by optimized processing solvent (THF/H2O cosolvent) showed enhanced π-π stacking domains of P3HT, resulting in semiconducting thin films with good electroactivity. Due to the presence of amide bonds in the gelatin backbone, Gel-g-P3HT underwent degradation over a period of 5 days, resulting in the formation of amphiphilic micellar nanoparticles that are biocompatible and nontoxic. The potential of these conductive and degradable graft copolymers was demonstrated in a pressure sensor. This research paves the way for developing biocompatible and enzymatically degradable polymer materials based on P3HT, enabling the next generation of transient polymer electronics for diverse applications, such as skin, implantable, and environmental electronics.