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Described herein is a novel visible-light-promoted three-component radical iodo-alkylative cyclization of alkynes using iodoform as a bifunctional iodine atom source. Visible-light irradiation of a polar-polar interaction complex of iodoform with malonate enables the cooperative hydrogen atom transfer process to generate alkyl radical and trigger a cascade reaction sequence.

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A novel and highly efficient Pd-catalyzed arylation of sulfenate anions with aryl thianthrenium salts is demonstrated. This procedure provides a practical protocol to synthesize various diaryl and alkyl aryl sulfoxides in moderate-to-good yields. The new approach shows mild reaction conditions, broad substrate scope, and good functional group tolerance.

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The behavior of the potassium alumanyl, [{SiNDipp}AlK]2 ({SiNDipp} = {CH2SiMe2N(Dipp)}2; Dipp = 2,6-i-Pr2C6H3), toward organic nitriles has been investigated. In common with earlier studies of the reactivity of charge neutral Al(I) species with multiply bonded small molecules, it is suggested that the initial step in all the reactions involves [2 + 1] cycloaddition and the generation of an [η2-C=N-Al] alumina azacyclopropane unit. In the cases of o- and m-tolyl-substituted aryl nitriles, this species is too kinetically labile to allow its isolation and undergoes C-C coupling via immediate Al-C/C≡N insertion to yield the alumina diazabutadiene derivatives. In contrast, the increased steric profile of alkyl nitriles imposes a marked influence on the nature of the products formed. Consistent with the proposed sequential pathway, reaction of [{SiNDipp}AlK]2 with t-BuCN provides an isolable alumina cyclopropane species that is kinetically resistant to onward reaction with a further nitrile equivalent. While reduction in the alkyl nitrile steric demands by use of i-PrCN again facilitates C-C bond formation, the crowding of the Al center by the resultant alumina-diazabutadienediide moiety appears to be beyond the limit of kinetic viability, resulting in an unusual 2-fold C-H to N-H isomerization from one of the C-iso-propyl substituents and the isolation of a 1-alumina-2,5-diazabutadiene structure.

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The evident seasonal variations in photovoltaic output as well as electric and thermal loads will result in significant energy wastage and carbon emissions. In order to address the problem, a two-stage sizing cooptimization method considering economy-safety characteristics is proposed for the integrated energy system combined power-hydrogen-heat cogeneration (CPHH-IES), with seasonal hydrogen storage. Subsequently, an economic-durability-safety optimized objective is introduced, assessing the total cost throughout the sizing cycle, equipment degradation during operation, and safety indicators of the hydrogen energy system. Finally, a two-stage sizing framework based on heat-determined hydrogen is established, and a combined configuration-scheduling double-layer strategy is put forward within the framework to accommodate seasonal hydrogen storage and multi-energy coupling. The feasibility of the method was validated using data from a site in northwest China, demonstrating its capacity to ensure the safety of the hydrogen energy system and enable seasonal hydrogen storage.

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Hepatitis C virus (HCV) belongs to the Flaviviridae family, and is a single-stranded RNA virus with positive polarity. It is the primary cause of hepatocellular carcinoma (HCC) worldwide. The treatment of HCV has entered a new era with the advent of direct-acting antiviral drugs (DAAs) and is associated with cure rates of more than 95%, making HCV the only curable viral disease. The successful treatment of chronic hepatitis C has greatly reduced, but not eliminated, the risk of HCC. Certain individuals, especially those with cirrhosis already present, remain vulnerable to HCC after achieving a sustained virological response (SVR). This article systematically reviews the recent studies on the risk and mechanisms of HCC development after HCV viral cure, the screening and predictive value of biological markers, and patient surveillance. Factors such as older age, diabetes, hepatic fat accumulation, alcohol use, and lack of fibrosis reversal are linked to increased HCC risk after HCV cure. The mechanism of HCC development after DAAs treatment remains unclear, but the possible mechanisms include immune cell dysfunction during HCV infection, cytokine network imbalance, epigenetic alterations, and host factors. Several biological markers and risk prediction models have been used to monitor the risk of HCC in CHC patients who have achieved SVR, but most still require validation and standardization. The implementation of risk-stratified surveillance programs is becoming urgent from a cost-effective point of view, but the availability of validated biomarkers to predict HCC in cured patients remains an unmet clinical need. Additionally, managing CHC patients who achieve SVR is becoming a growing challenge as an increasing number of HCV patients are cured.

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We report herein a three-component radical arylalkylation of [1.1.1]propellane toward the synthesis of aryl-substituted bicyclo[1.1.1]pentane derivatives. The use of electron-deficient aryl cyanide as an aryl group source not only reduces the energy barrier of the arylation of the nucleophilic alkyl radical species, but also suppresses the electrophilic Friedel-Crafts alkylation process, enabling the present site-selective arylalkylation.

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BACKGROUND: History-taking is an essential clinical competency for qualified doctors. The limitations of the standardized patient (SP) in taking history can be addressed by the virtual standardized patient (VSP). This paper investigates the accuracy of virtual standardized patient simulators and evaluates the applicability of the improved system's accuracy for diagnostic teaching support and performance assessment. METHODS: Data from the application of VSP to medical residents and students were gathered for this prospective study. In a human-machine collaboration mode, students completed exams involving taking SP histories while VSP provided real-time scoring. Every participant had VSP and SP scores. Lastly, using the voice and text records as a guide, the technicians will adjust the system's intention recognition accuracy and speech recognition accuracy. RESULTS: The research revealed significant differences in scoring across several iterations of VSP and SP (p < 0.001). Across various clinical cases, there were differences in application accuracy for different versions of VSP (p < 0.001). Among training groups, the diarrhea case showed significant differences in speech recognition accuracy (Z = -2.719, p = 0.007) and intent recognition accuracy (Z = -2.406, p = 0.016). Scoring and intent recognition accuracy improved significantly after system upgrades. CONCLUSION: VSP has a comprehensive and detailed scoring system and demonstrates good scoring accuracy, which can be a valuable tool for history-taking training.

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BACKGROUND AND AIMS: Hemostatic powder (HP) is a novel hemostasis modality for nonvariceal gastrointestinal (GI) bleeding. The meta-analysis was performed to evaluate the efficacy of HP monotherapy versus conventional endoscopic treatment (CET) for nonvariceal GI bleeding. METHODS: PubMed, Embase, and Cochrane Library databases were systematically searched from inception to October 16, 2023. The primary outcomes were the initial hemostatic rate and the 30-day rebleeding rate. After the meta-analysis, the trial sequential analysis (TSA) was also conducted to decrease the risk of random errors and validate the result. RESULTS: The meta-analysis included eight studies, incorporating 653 patients in total. Given significant heterogeneity, all analyses were segregated into malignancy-related and non-malignancy-related GI bleeding lesions. For the former, HP monotherapy significantly improved the initial hemostasis rate and 30-day rebleeding rate compared to CET (Relative risk [RR] 1.50, 95% confidence interval [CI] 1.28 - 1.75, P < .001; RR .32, 95% CI .12 - .86, P = .02), and TSA supported the above results. For non-malignancy-related GI bleeding, HP monotherapy and CET have similar initial hemostasis and 30-day rebleeding rates (RR 1.08, 95% CI .98 - 1.19, P = .11; RR 1.15, 95% CI .46 - 2.90, P = .76), but the TSA failed to confirm the above results. CONCLUSIONS: In conclusion, HP monotherapy surpassed CET in terms of the initial hemostasis rate and 30-day rebleeding rate for patients with malignancy-related GI bleeding. However, their relative efficacy for non-malignancy-related GI bleeding remains unresolved.

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Alpha-amylase and beta-amylase coexist as mixtures in industrial production, and the two amylases have active synergistic effects when they approach each other. These effects are due to enhanced enzyme binding affinity for the substrate and the rate of particle hydrolysis. Here, we report the allosteric mechanism of this synergistic effect in α- and ß-amylase mixtures. The assay showed higher activity after mixing α- and ß-amylase. Molecular docking showed that α- and ß-amylase create a stable dual-enzyme complex with high binding energy, and that complex formation does not affect the exposure of respective active sites. ß-Amylase is specifically bound to the B domain of α-amylase, and the dynamic plasticity of the B domain makes it move spatially, and this adjustment leads to a more open conformation in the active site of α-amylase. Because the enzymes binding make the complex more stable, the degree to which the relative activity of the dual-enzyme complex is inhibited is significantly reduced. After enzyme hydrolysis, the products maltose and glucose accumulate and produce competitive inhibition, which explains the relative activity decrease of the later-stage dual-enzyme cooperation. Structural characterization by FT-IR and CD spectroscopy did not reveal significant changes in respective secondary structures after enzyme binding.

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The objective of this investigation study is to examine the levels of burnout and work engagement among nurses working on the front lines of the COVID-19 pandemic. Additionally, we aim to analyze the risk factors associated with nurse burnout. This investigation study included a sample of 1764 registered nurses from 6 tertiary comprehensive hospitals in Wuhan. A total of 1800 questionnaires were distributed via email between January 2021 and July 2021, and 1764 completed questionnaires were returned. Nurses who had been on the front lines of the COVID-19 fight for more than six months were included in the study. The Maslach Burnout Inventory-General Survey (MBI-GS) scale was utilized to assess burnout levels among all nurses. Work engagement was measured using the Utrecht Work Engagement Scale (UWES). The general health of the nurses was evaluated using the General Health Questionnaire-12 (GHQ-12) score. Demographic and clinical data, including age, sex, hospital, department, education, years of experience, daily overtime, weekly rest time, number of night shifts per month, smoking or drinking habits, marital status, etc, were also collected. Statistical analyses were performed using SPSS 25.0. The GHQ-12 scores in the FC group were significantly higher than those in the non-frontline COVID-19 (NFC) group. Compared to the average value of the 2 groups, we found that the dimension 2 average value of UWES in NFC group (3.52 ±â€…1.07) were remarkably higher than that in FC group (3.40 ±â€…1.08, P < .05). Furthermore, the dimension 1 (emotional exhaustion) average value and dimension 2 (depersonalization) average value of MBI-GS in NFC group were remarkably declined than that in FC group. Spearman rank correlation showed that negative correlation among the average value of each dimension and the overall average values between MBI-GS and UWES. Logistic regression analysis showed that daily Overtime, fight against COVID-19, GHQ-12 score and dimension 2 of UWES were the risk factors for nurse burnout. In summary, this study showed that the dimension 1 (emotional exhaustion) average value and dimension 2 (depersonalization) average value of MBI-GS in NFC group were remarkably declined than that in FC group. This study may provide some basis for addressing nurse burnout.

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Exercise-induced muscle injury is one of the most common types of sports injuries. Skeletal muscle troponin I (skTnI) serves as an ideal biomarker in assessing such injuries, facilitating timely detection and evaluation. In this study, we develop a fluorescent sandwich lateral flow immunoassay (LFIA) combined with a desktop analyzer for rapid detection of skTnI. Through optimizing the reaction system, the assay achieves a satisfying detection performance, reaching a limit of detection (LOD) of 0.5 ng/mL with a turnaround time of 15 min. The proposed detection platform offers portability, ease of use, and high sensitivity, which facilitates the monitoring of exercise-induced muscle injuries at the point of care. This feature is particularly advantageous for end users, enabling timely detection of sports-related injuries and ultimately enhancing prognosis and sports life.

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Macrocycle-to-macrocycle conversion is an effective strategy to construct new macrocyclic arenes with specific structures. Herein, a new class of chiral macrocyclic arene, namely, octopus[5]arenes (Oc5s), cannot be synthesized by the direct approach from the corresponding chiral monomers but can be successfully achieved by a macrocycle-to-macrocycle conversion strategy utilizing racemic pagoda[5]arenes as the starting materials. It was found that enantiomeric Oc5s showed fixed conformations and stable chiral structures and exhibited significant chiral recognition toward chiral diamines.

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The separation and purification of chemical raw materials, particularly neutral compounds with similar physical and chemical properties, represents an ongoing challenge. In this study, we introduce a class of water-soluble macrocycle compound, calix[2]azolium[2]benzimidazolone (H), comprising two azolium and two benzimidazolone subunits. The heterocycle subunits form a hydrophobic binding pocket that enables H1 to encapsulate a series of neutral guests in water with 1:1 or 2:1 stoichiometry, including aldehydes, ketones, and nitrile compounds. The host-guest complexation in the solid state was further confirmed through X-ray crystallography. Remarkably, H1 was shown to be a nonporous adaptive crystal material to separate valeraldehyde from the mixture of valeraldehyde/2-methylbutanal/pentanol with high selectivity and recyclability in the solid states. This work not only demonstrates that azolium-based macrocycles are promising candidates for the encapsulation of organic molecules but also shows the potential application in separation science.

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The development of highly efficient and durable alkaline hydrogen evolution reaction (HER) catalysts is crucial for achieving high-performance practical anion exchange membrane water electrolyzer (AEMWE) at ampere-level current density. Herein, we report a design concept by employing Ga single atoms as an electronic bridge to stabilize the Ru clusters for boosting alkaline HER performance in practical AEMWE. Experimental and theoretical results collectively reveal that the bridged Ga sites trigger strong metal-support interaction for the homogeneous distribution of Ru clusters with high density, as well as optimize the Ru-H bond strength due to the electron transfer between Ru and Ga for enhanced intrinsic HER activity. Moreover, the oxophilic Ga sites near the Ru clusters tend to adsorb the hydroxyl species and accelerate the water dissociation for sufficient proton supplement in an alkaline medium. The Ru-GaSA/N-C catalyst exhibits a low overpotential of 4 ± 1 mV (10 mA cm-2) and high mass activity of 9.3 ± 0.5 A mg-1Ru at -0.05 V vs RHE. In particular, the Ru-GaSA/N-C-based AEMWE in 1 M KOH delivers a voltage of only 1.74 V to reach an industrial current density of 1 A cm-2, and can steadily operate at 1 A cm-2 for more than 170 h.

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Resting-state functional magnetic resonance imaging (rs-fMRI) has been widely used in the identification of mild cognitive impairment (MCI) research, MCI patients are relatively at a higher risk of progression to Alzheimer's disease (AD). However, almost machine learning and deep learning methods are rarely analyzed from the perspective of spatial structure and temporal dimension. In order to make full use of rs-fMRI data, this study constructed a dynamic spatiotemporal graph neural network model, which mainly includes three modules: temporal block, spatial block, and graph pooling block. Our proposed model can extract the BOLD signal of the subject's fMRI data and the spatial structure of functional connections between different brain regions, and improve the decision-making results of the model. In the study of AD, MCI and NC, the classification accuracy reached 83.78% outperforming previously reported, which manifested that our model could effectively learn spatiotemporal, and dynamic spatio-temporal method plays an important role in identifying different groups of subjects. In summary, this paper proposed an end-to-end dynamic spatio-temporal graph neural network model, which uses the information of the temporal dimension and spatial structure in rs-fMRI data, and achieves the improvement of the three classification performance among AD, MCI and NC.

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Recent advancements in artificial intelligence (AI) herald transformative potentials for reshaping glaucoma clinical management, improving screening efficacy, sharpening diagnosis precision, and refining the detection of disease progression. However, incorporating AI into healthcare usages faces significant hurdles in terms of developing algorithms and putting them into practice. When creating algorithms, issues arise due to the intensive effort required to label data, inconsistent diagnostic standards, and a lack of thorough testing, which often limits the algorithms' widespread applicability. Additionally, the "black box" nature of AI algorithms may cause doctors to be wary or skeptical. When it comes to using these tools, challenges include dealing with lower-quality images in real situations and the systems' limited ability to work well with diverse ethnic groups and different diagnostic equipment. Looking ahead, new developments aim to protect data privacy through federated learning paradigms, improving algorithm generalizability by diversifying input data modalities, and augmenting datasets with synthetic imagery. The integration of smartphones appears promising for using AI algorithms in both clinical and non-clinical settings. Furthermore, bringing in large language models (LLMs) to act as interactive tool in medicine may signify a significant change in how healthcare will be delivered in the future. By navigating through these challenges and leveraging on these as opportunities, the field of glaucoma AI will not only have improved algorithmic accuracy and optimized data integration but also a paradigmatic shift towards enhanced clinical acceptance and a transformative improvement in glaucoma care.

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Background: A range of imaging modalities have reported Alzheimer's disease-related abnormalities in individuals experiencing subjective cognitive decline (SCD). However, there has been no consistent local abnormality identified across multiple neuroimaging modalities for SCD. Objective: We aimed to investigate the convergent local alterations in amyloid-ß (Aß) deposition, glucose metabolism, and resting-state functional MRI (RS-fMRI) metrics in SCD. Methods: Fifty SCD patients (66.4±5.7 years old, 19 men [38%]) and 15 normal controls (NC) (66.3±4.4 years old, 5 men [33.3%]) were scanned with both [18F]-florbetapir PET and [18F]-fluorodeoxyglucose PET, as well as simultaneous RS-fMRI from February 2018 to November 2018. Voxel-wise metrics were retrospectively analyzed, including Aß deposition, glucose metabolism, amplitude of low frequency fluctuation (ALFF), regional homogeneity (ReHo), and degree centrality(DC). Results: The SCD group showed increased Aß deposition and glucose metabolism (p < 0.05, corrected), as well as decreased ALFF, ReHo, and DC (p < 0.05, uncorrected) in the left dorsal precuneus (dPCu). Furthermore, the dPCu illustrated negative resting-state functional connectivity with the default mode network. Regarding global Aß deposition positivity, the Aß deposition in the left dPCu showed a gradient change, i.e., Aß positive SCD > Aß negative SCD > Aß negative NC. Additionally, both Aß positive SCD and Aß negative SCD showed increased glucose metabolism and decreased RS-fMRI metrics in the dPCu. Conclusions: The dorsal precuneus, an area implicated in early AD, shows convergent neuroimaging alterations in SCD, and might be more related to other cognitive functions (e.g., unfocused attention) than episodic memory.

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INTRODUCTION: The systemic inflammatory response index (SIRI) is a novel indicator of systemic inflammation derived from the absolute counts of neutrophils, monocytes, and lymphocytes. The aim of this meta-analysis was to evaluate the association between SIRI and functional outcome in patients with acute ischemic stroke (AIS). METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed in this meta-analysis. Relevant cohort studies were retrieved by a search of electronic databases including PubMed, Web of Science, Embase, Wanfang, and China National Knowledge Infrastructure from database inception to February 9, 2024. A poor functional outcome was defined as a modified Rankin Scale ≥ 3 within 3 months after disease onset. A random-effects model was used to combine the data by incorporating the influence of between-study heterogeneity. The protocol of the meta-analysis was not prospectively registered in PROSPERO. RESULTS: Fourteen cohort studies were included. Pooled results showed that a high SIRI at admission was associated with increased risk of poor functional outcome within 3 months (odds ratio [OR]: 1.57, 95% confidence interval: 1.39 to 1.78, p < 0.001; I2 = 0%). Results of the meta-regression analysis suggested that the cutoff for defining a high SIRI was positively related to the OR for the association between SIRI and the risk of poor functional outcome (coefficient = 0.13, p = 0.03), while other variables including sample size, mean age, severity of stroke at admission, percentage of men, current smokers, or patients with diabetes did not significantly modify the results. Subgroup analyses according to study design, main treatments, and study quality scores showed similar results. CONCLUSION: A high SIRI may be associated with a poor functional outcome in patients after AIS.

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This study proposed combining food waste (FW) and cattle manure (CM) in composting to improve the product maturity. The findings suggested that the inclusion of CM effectively extended the thermophilic stage, facilitated the decomposition of cellulose, and enhanced the production of humus-like substances by enhancing beneficial microbial cooperation. Adding 40 % CW was optimal to reduce the nitrogen loss, increase the cellulose degradation rate to 22.07 %, increase germination index (GI) to 140 %, and reduce normalized antibiotic resistance gene (ARG) abundances. Adding CW could promote the transformation of protein-like compounds, thereby enhancing the humification process of organic substances. Structural equation modeling further verified that the temperature was the key factor affecting humification production, while the main driver for ARGs was physiochemical parameters. This study shows that co-composting of FW and CM offers the potential to promote humification, reduce ARG abundance, and improve fertilizer quality for utilization of both biowastes in the field.

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