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Recently developed optogenetic technology, which allows high-fidelity control of neuronal activity, has been applied to investigate the neural circuits underlying sensory processing and behavior. The nasal cavity is innervated by the olfactory nerve and trigeminal nerve, which are closely related to common symptoms of rhinitis, such as impairment of smell, itching, and sneezing. The olfactory system has an amazing ability to distinguish thousands of odorant molecules at trace levels. However, there are many issues in olfactory sensing mechanisms that need to be addressed. Optogenetics offers a novel technical approach to solve this dilemma. Therefore, we review the recent advances in olfactory optogenetics to clarify the mechanisms of chemical sensing, which may help identify the mechanism of dysfunction and suggest possible treatments for impaired smell. Additionally, in rhinitis patients, alterations in the other nerve (trigeminal nerve) that innervates the nasal cavity can lead to hyperresponsiveness to various nociceptive stimuli and central sensitization, causing frequent and persistent itching and sneezing. In the last several years, the application of optogenetics in regulating nociceptive receptors, which are distributed in sensory nerve endings, and amino acid receptors, which are distributed in vital brain regions, to alleviate overreaction to nociceptive stimuli, has gained significant attention. Therefore, we focus on the progress in optogenetics and its application in neuromodulation of nociceptive stimuli and discuss the potential clinical translation for treating rhinitis in the future.
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Optogenética , Optogenética/métodos , Humanos , Animais , Olfato/fisiologia , Nariz/fisiologia , Nervo Trigêmeo/fisiologia , Nervo Trigêmeo/fisiopatologia , Rinite/terapia , Rinite/fisiopatologia , Nervo Olfatório/fisiologia , Cavidade Nasal/fisiologiaRESUMO
OBJECTIVE: We review the prevalence of allergic diseases in children across prenatal exposures to heavy metals. METHODS: This systematic review and meta-analysis is registered in the PROSPERO database (CRD42023478471). A comprehensive search of PubMed, Web of Science, Medline and Cochrane library was conducted from the database inception until 31 October 2023. The Newcastle-Ottawa Quality Assessment Scale (NOS) was used to assess the quality of included studies. We used a random-effects model to summarize the effects from the studies. RESULTS: A total of 16 studies were included, 120,065 mother-child pairs enrolled. The NOS scores indicated that the quality of the literature included in the study was of a high standard. CONCLUSION: The final results indicate that prenatal exposure to Pb increased the incidence of wheeze and Eczema in infants, and exposure to Ni and CD increased the incidence of AD in infants.
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Hydrogel sensors are widely utilized in soft robotics and tissue engineering due to their excellent mechanical properties and biocompatibility. However, in high-water environments, traditional hydrogels can experience significant swelling, leading to decreased mechanical and electrical performance, potentially losing shape, and sensing capabilities. This study addresses these challenges by leveraging the Hofmeister effect, coupled with directional freezing and salting-out techniques, to develop a layered, high-strength, tough, and antiswelling PVA/MXene hydrogel. In particular, the salting-out process enhances the self-entanglement of PVA, resulting in an S-PM hydrogel with a tensile strength of up to 2.87 MPa. Furthermore, the S-PM hydrogel retains its structure and strength after 7 d of swelling, with only a 6% change in resistance. Importantly, its sensing performance is improved postswelling, a capability rarely achievable in traditional hydrogels. Moreover, the S-PM hydrogel demonstrates faster response times and more stable resistance change rates in underwater tests, making it crucial for long-term continuous monitoring in challenging aquatic environments, ensuring sustained operation and monitoring.
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Objective: To integrate pharmacovigilance and network toxicology methods to explore the potential adverse drug events (ADEs) and toxic mechanisms of selumetinib, and to provide a reference for quickly understanding the safety and toxicological mechanisms of newly marketed drugs. Methods: Taking selumetinib as an example, this study integrated pharmacovigilance methods based on real-world data and network toxicology methods to analyze its ADE and its potential toxicological mechanism. First, the ADE reports of selumetinib were extracted from the US Food and Drug Administration (FDA) adverse event reporting system (FAERS), and the ADE signals were detected by reporting odds ratio (ROR) and UK medicines and healthcare products regulatory agency (MHRA) methods. The ADE signals were classified and described according to the preferred terms (PTs) and system organ class (SOC) derived from the Medical Dictionary for Regulatory Activities (MedDRA). The network toxicology method was used to analyze the toxicological mechanism of the interested SOCs. The specific steps included predicting the potential targets of selumetinib using TOXRIC, STITCH, ChEMBL, CTD, SwissTargetPreditcion, and Super-PRED databases, collecting the targets of SOC using GeneCards database, conducting protein-protein interaction (PPI) analysis through STRING database, conducting gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analysis through DAVID database, and testing the molecular affinity using AutoDock software. Results: A total of 1388 ADE reports related to selumetinib were extracted, and 53 positive signals were detected by ROR and MHRA methods, of which 20 signals were not mentioned in the package insert, including ingrowing nail, hyperphosphatemia, cardiac valve disease, hematuria, neutropenia, etc. Analysis of the toxicological mechanism of six SOCs involved in positive ADE signals revealed that the key targets included EGFR, STAT3, AKT1, IL6, BCL2, etc., and the key pathways included PI3K/Akt pathway, apoptosis, ErbB signaling pathway, and EGFR tyrosine kinase inhibitor resistance, etc. Molecular docking assays showed spontaneous binding of selumetinib to key targets in these pathways. Conclusion: The pharmacovigilance analysis identified some new potential ADEs of selumetinib, and the network toxicology analysis showed that the toxic effects of selumetinib may be related to PI3K/Akt pathway, apoptosis, ErbB signaling pathway, EGFR tyrosine kinase inhibitor resistance and other pathways.
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Introduction: Insomnia during pregnancy presents significant medical care challenges and heightens the risk of adverse outcomes for both pregnant women and fetuses. This study undertook a meta-analysis to assess the global prevalence of insomnia during pregnancy, examining both the overall prevalence and regional variations. Method: The aim of this study was to perform a meta-analysis of articles indexed in PubMed, Embase, and Web of Science from the inception of these databases up to February 29, 2024. The study systematically reviewed the global prevalence of gestational insomnia and explored potential moderating factors, encompassing research type, publication date, regional influences, maternal age, pregnancy status, depressive symptoms, and anxiety symptoms. Result: Forty-four studies, encompassing a total of 47,399,513 participants, were included in the analysis. The overall prevalence of insomnia symptoms during pregnancy was 43.9%. Regional factors and depression emerged as the main factors affecting insomnia, with Europe (53.6%) surpassing North America (41.0%), followed by South America (50.6%) and Asia (40.7%). High depression rates (56.2%) correlated with increased insomnia prevalence compared to low depression rates (39.8%). The type of research and publication date showed no significant impact on the prevalence of insomnia symptoms. Conclusion: The meta-analysis results indicated that the prevalence of insomnia symptoms was higher during pregnancy, especially among pregnant women who were in a highly depressed state or located in the European region. Systematic review registration: PROSPERO, identifier CRD42018104460.
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Observational studies have reported an association between inflammatory bowel disease (IBD), which includes Crohn's disease (CD) and ulcerative colitis (UC), and hemorrhoids (HEM). However, the presence of a causal relationship within this observed association remains to be confirmed. Consequently, we utilized the Mendelian randomization (MR) method to assess the causal effects of IBD on hemorrhoids. We validated the association between IBD and hemorrhoids in humans based on genome-wide association studies (GWAS) data. To investigate the causal relationship between IBD and hemorrhoids, we performed a two-sample Mendelian randomization study using training and validation sets. The genetic variation data for IBD, CD, UC, and hemorrhoids were derived from published genome-wide association studies (GWAS) of individuals of European. Two-sample Mendelian randomization and Multivariable Mendelian randomization (MVMR) were employed to determine the causal relationship between IBD (CD or UC) and hemorrhoids. Genetically predicted overall IBD was positively associated with hemorrhoids risk, with ORs of 1.02 (95% CIs 1.01-1.03, P = 4.39 × 10-4) and 1.02 (95% CIs 1.01-1.03, P = 4.99 × 10-5) in the training and validation sets, respectively. Furthermore, we found that CD was positively associated with hemorrhoids risk, with ORs of 1.02 (95% CIs 1.01-1.03, P = 4.12 × 10-6) and 1.02 (95% CIs 1.01-1.02, P = 3.78 × 10-5) for CD in the training and validation sets, respectively. In addition, we found that UC in the training set was positively associated with hemorrhoids risk (ORs 1.02, 95% CIs 1.01-1.03, P = 4.65 × 10-3), while no significant causal relationship between UC and hemorrhoids was shown in the validation set (P > 0.05). However, after MVMR adjustment, UC in the training set was not associated with an increased risk of hemorrhoids. Our study showed that there is a causal relationship between CD and hemorrhoids, which may suggest that clinicians need to prevent the occurrence of hemorrhoids in CD patients.
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Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Hemorroidas , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Humanos , Hemorroidas/genética , Hemorroidas/epidemiologia , Doenças Inflamatórias Intestinais/genética , Fatores de Risco , Doença de Crohn/genética , Doença de Crohn/epidemiologia , Colite Ulcerativa/genéticaRESUMO
BACKGROUND: Hemolytic disease of the newborn (HDN) is a common condition that can have a severe impact on the health of newborns due to the hemolytic reactions it triggers. Although numerous studies have focused on understanding the pathogenesis of HDN, there are still many unanswered questions. METHODS: In this retrospective study, serum samples were collected from 15 healthy newborns and 8 infants diagnosed with hemolytic disease. The relationship between different metabolites and various IgG subtypes in Healthy, HDN and BLI groups was studied by biochemical technique and enzyme-linked immunosorbent assay (ELISA). Metabolomics analysis was conducted to identify the differential metabolites associated with HDN. Subsequently, Pearson's correlation analysis was used to determine the relation of these differential metabolites with IgG isoforms. The relationship between the metabolites and IgG subtypes was observed after treatment. RESULTS: The study results revealed that infants with hemolytic disease exhibited abnormal elevations in TBA, IgG1, IgG2a, IgG2b, IgG3, and IgG4 levels when compared to healthy newborns. Additionally, differences in metabolite contents were also observed. N, N-DIMETHYLARGININE showed negative correlations with TBA, IgG1, IgG2a, IgG2b, IgG3, and IgG4, while 2-HYDROXYBUTYRATE, AMINOISOBUTANOATE, Inosine, and ALLYL ISOTHIOCYANATE exhibited positive correlations with TBA, IgG1, IgG2a, IgG2b, IgG3, and IgG4. Through metabolomics-based research, we have discovered associations between differential metabolites and different IgG isoforms during the onset of HDN. CONCLUSION: These findings suggest that changes in metabolite and IgG isoform levels are linked to HDN. Understanding the involvement of IgG isoforms and metabolites can provide valuable guidance for the diagnosis and treatment of HDN.
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Imunoglobulina G , Metabolômica , Isoformas de Proteínas , Humanos , Imunoglobulina G/sangue , Recém-Nascido , Metabolômica/métodos , Feminino , Masculino , Estudos Retrospectivos , Eritroblastose Fetal/sangue , Eritroblastose Fetal/metabolismo , Eritroblastose Fetal/diagnósticoRESUMO
Alloying has proven power to upgrade metallic electrocatalysts, while the traditional alloys encounter limitation for optimizing electronic structures of surface metallic sites in a continuous manner. High-entropy alloys (HEAs) overcome this limitation by manageably tuning the adsorption/desorption energies of reaction intermediates. Recently, the marriage of nanotechnology and HEAs has made considerable progresses for renewable energy technologies, showing two important trends of size diminishment and multidimensionality. This review is dedicated to summarizing recent advances of HEAs that are rationally designed for energy electrocatalysis. We first explain the advantages of HEAs as electrocatalysts from three aspects: high entropy, nanometer, and multidimension. Then, several structural regulation methods are proposed to promote the electrocatalysis of HEAs, involving the thermodynamically nonequilibrium synthesis, regulating the (sub-)nanosize and anisotropic morphologies, as well as engineering the atomic ordering. The general relationship between the electronic structures and electrocatalytic properties of HEAs is further discussed. Finally, we outline remaining challenges of this field, aiming to inspire more sophisticated HEA-based nanocatalysts.
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Cathode-electrolyte interphase (CEI) is crucial for the reversibility of rechargeable batteries, yet receives less attention compared to solid-electrolyte interphase (SEI). The prevalent weakly-solvating electrolyte is usually proposed from the standing point of obtaining robust SEI, however, the resultant weak ion-solvent interaction gives rise to excessive free solvents and forms thick CEI with high kinetic barriers, which is disadvantageous for interfacial stability at the high working voltage. Herein, a highly-solvating electrolyte is reported to immobilize free solvents by generating stable ternary complexes and facilitate the growth of homogeneous and ultrathin CEI to boost the electrochemical performances of potassium-ion batteries (PIBs). Through time-of-flight secondary ion mass spectrometry and cryogenic transmission electron microscopy, It is revealed that the deliberately coordinated complexes are the key to forming mechanically stable and inorganic-rich CEI with superior diffusion kinetics for high-performing PIBs. Coupling with a K0.5MnO2 cathode and a soft carbon (SC) anode, a high energy density (202.3 Wh kg-1) is achieved with an exceptional cycle lifespan (92.5% capacity retention after 500 cycles) in a SC||K0.5MnO2 full cell, setting new performance benchmarks for PIBs.
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This study aimed to investigate the chemical components and potential health benefits of the fruits of Cannabis sativa L. Fourteen new phenylpropanamides designated as cannabisin I-XIV (1-14) and 40 known analogs were isolated and characterized via nuclear magnetic resonance spectroscopy, high-resolution electrospray ionization mass spectrometry, and electronic circular dichroism. In vitro bioassay using H2O2-induced PC12 cell damage models demonstrated that hempseeds extract and compounds 1, 3, 15, 26, 30, 36, 41, and 48 exhibited neuroprotective properties. 3,3'-Demethylgrossamide (30) displayed encouraging protection activity, which was further investigated to relieve the oxidative stress and apoptosis of PC12 cells treated with H2O2. The isolation and characterization of these neuroprotective phenylpropanamides from the fruits of C. sativa provide insights into its health-promoting properties as a healthy food and herbal medicine for preventing and treating neurodegenerative diseases, especially Alzheimer's disease.
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Cannabis , Frutas , Fármacos Neuroprotetores , Extratos Vegetais , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Ratos , Células PC12 , Animais , Frutas/química , Cannabis/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Amidas/química , Amidas/farmacologia , Peróxido de Hidrogênio , HumanosRESUMO
Coal shale gas is an important type of shale gas. The microscopic pore size distribution and pore structure characteristics of coal shale determine the macroscopic storage and transportation of coal shale gas. In order to quantitatively characterize the microscopic pore size distribution and pore structure properties of coal shale from a multiscale perspective, the pore size distribution and pore structure of coal shale specimens with different grain sizes were quantitatively characterized using low-temperature N2/CO2 adsorption and high-pressure mercuric pressure methods, taking the coal shale of high-gas mines of the Dongbaowei Mine in the Shuangyashan Basin as the object of study. The pore size distribution fractal pattern and pore structure characteristics of coal shale were quantitatively analyzed by the joint characterization method of the coal shale pore fractal theory and pore size distribution. Relevant experimental studies found the following: (1) The specific surface area and volume of coal shale pores and fractures decrease gradually with the increase in coal shale grain size. (2) The pore size distribution of coal shale has obvious fractal characteristics at the stages of high and low mercury pressures, and the demarcation point of medium and large pores is 55 nm. (3) The difference in pore and fracture structural parameters between coal shale with different grain sizes and the original rock specimens is relatively small, and it is feasible to study the general rules of gas adsorption, desorption, diffusion, and seepage in the pores and fractures of coal shale by using coal shale shapes instead of the original rock specimens.
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The micro-scale gas adsorption-desorption characteristics determine the macro-scale gas transport and production behavior. To reveal the three-dimensional stress state-induced gas adsorption-desorption characteristics in coal-bearing shale reservoirs from a micro-scale perspective, the coal-bearing shale samples from the Dongbaowei Coal Mine in the Shuangyashan Basin were chosen as the research subject. Isothermal adsorption-desorption experiments under three-dimensional stress state were conducted using the low field nuclear magnetic resonance (L-NMR) T2 spectrum method to simulate the in-situ coal-bearing shale gas adsorption-desorption process. The average effective stress was used as the equivalent stress indicator for coal-bearing shale, and the integral of nuclear magnetic resonance T2 spectrum amplitude was employed as the gas characterization indicator for coal-bearing shale. A quantitative analysis was performed to examine the relationship between gas adsorption in coal-bearing shale and the average effective stress. And a quantitative analysis was performed to examine the relationship between the macroscopic and microscopic gas quantities of coal-bearing shale. Experimental findings: (1) The adsorption-desorption process of coal-bearing shale gas follows the L-F function model and the D-A-d function model respectively with respect to the amount of gas and the average effective stress. (2) There is a logarithmic relationship between the macroscopic and microscopic gas quantities of coal-bearing shale during the adsorption-desorption process. This quantitatively characterizes the differences in the curves, which may be related to the elastic-plastic deformation, damage and fracture of the micropores in coal-bearing shale, as well as the hysteresis of gas desorption and the stress field of the gas occurrence state.
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AIM: To extend and form the "Grading of Recommendations Assessment, Development and Evaluation in Traditional Chinese Medicine" (GRADE-TCM). METHODS: Methodologies were systematically reviewed and analyzed concerning evidence-based TCM guidelines worldwide. A survey questionnaire was developed based on the literature review and open-end expert interviews. Then, we performed expert consensus, discussion meeting, opinion collection, external examination, and the GRADE-TCM was formed eventually. RESULTS: 265 Chinese and English TCM guidelines were included and analyzed. Five experts completed the open-end interviews. Ten methodological entries were summarized, screened and selected. One round of consensus was conducted, including a total of 22 experts and 220 valid questionnaire entries, concerning 1) selection of the GRADE, 2) GRADE-TCM upgrading criteria, 3) GRADE-TCM evaluation standard, 4) principles of consensus and recommendation, and 5) presentation of the GRADE-TCM and recommendation. Finally, consensus was reached on the above 10 entries, and the results were of high importance (with voting percentages ranging from 50 % to 81.82 % for "very important" rating) and strong reliability (with the Cr ranging from 0.93 to 0.99). Expert discussion meeting (with 40 experts), opinion collection (in two online platforms) and external examination (with 14 third-party experts) were conducted, and the GRADE-TCM was established eventually. CONCLUSION: GRADE-TCM provides a new extended evidence-based evaluation standard for TCM guidelines. In GRADE-TCM, international evidence-based norms, characteristics of TCM intervention, and inheritance of TCM culture were combined organically and followed. This is helpful for localization of the GRADE in TCM and internationalization of TCM guidelines.
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Medicina Baseada em Evidências , Medicina Tradicional Chinesa , Medicina Tradicional Chinesa/métodos , Reprodutibilidade dos Testes , Inquéritos e QuestionáriosRESUMO
PURPOSE: To evaluate and compare the diagnostic performances of whole-lesion iodine map (IM) histogram analysis and single-slice IM measurement in the risk classification of gastrointestinal stromal tumors (GISTs). METHODS: Thirty-seven patients with GISTs, including 19 with low malignant underlying GISTs (LG-GISTs) and 18 with high malignant underlying GISTs (HG-GISTs), were evaluated with dual-energy computed tomography (DECT). Whole-lesion IM histogram parameters (mean; median; minimum; maximum; standard deviation; variance; 1st, 10th, 25th, 50th, 75th, 90th, and 99th percentile; kurtosis, skewness, and entropy) were computed for each lesion. In other sessions, iodine concentrations (ICs) were derived from the IM by placing regions of interest (ROIs) on the tumor slices and normalizing them to the iodine concentration in the aorta. Both quantitative analyses were performed on the venous phase images. The diagnostic accuracies of the two methods were assessed and compared. RESULTS: The minimum, maximum, 1st, 10th, and 25th percentile of the whole-lesion IM histogram and the IC and normalized IC (NIC) of the single-slice IC measurement significantly differed between LG- and HG-GISTs (p < 0.001 - p = 0.042). The minimum value in the histogram analysis (AUC = 0.844) and the NIC in the single-slice measurement analysis (AUC = 0.886) showed the best diagnostic performances. The NIC of single-slice measurements had a diagnostic performance similar to that of the whole-lesion IM histogram analysis (p = 0.618). CONCLUSIONS: Both whole-lesion IM histogram analysis and single-slice IC measurement can differentiate LG-GISTs and HG-GISTs with similar diagnostic performances.
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Meios de Contraste , Tumores do Estroma Gastrointestinal , Tomografia Computadorizada por Raios X , Humanos , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso de 80 Anos ou mais , Estudos Retrospectivos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Medição de Risco , Neoplasias Gastrointestinais/diagnóstico por imagemRESUMO
The electroreduction of CO2 to high-value products is a promising approach for achieving carbon neutrality. Among these products, formic acid stands out as having the most potential for industrialization due to its optimal economic value in terms of consumption and output. In recent years, the Faraday efficiency of formic acid from CO2 electroreduction has reached 90~100 %. However, this high selectivity cannot be maintained for extended periods under high currents to meet industrial requirements. This paper reviews excellent work from the perspective of catalyst stability, summarizing and discussing the performance of typical catalysts. Strategies for preparing stable and highly active catalysts are also briefly described. This review may offer a useful data reference and valuable guidance for the future design of long-stability catalysts.
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Benzobicyclo[3.2.1]octane is a cage-like unique motif containing a bicyclo[3.2.1]octane structure fused with at least one benzene ring. It is found in various natural products that exhibit structural complexities and important biological activities. The total synthesis of natural products possessing this challenging structure has received considerable attention, and great advances have been made in this field during the past 15â years. This review summarizes thus far achieved chemical syntheses and synthetic studies of natural compounds featuring the benzobicyclo[3.2.1]octane core. It focuses on strategic approaches constructing the bridged structure, aiming to provide a useful reference for inspiring further advancements in strategies and total syntheses of natural products with such a framework.
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As endoscopic imaging technology advances, there is a growing clinical demand for enhanced imaging capabilities. Although conventional white light imaging (WLI) endoscopy offers realistic images, it often cannot reveal detailed characteristics of the mucosa. On the other hand, optical staining endoscopy, such as Compound Band Imaging (CBI), can discern subtle structures, serving to some extent as an optical biopsy. However, its image brightness is low, and the colors can be abrupt. These two techniques, commonly used in clinical settings, have complementary advantages. Nonetheless, they require different lighting conditions, which makes it challenging to combine their imaging strengths on living tissues. In this study, we introduce a novel endoscopic imaging technique that effectively combines the advantages of both WLI and CBI. Doctors don't need to manually switch between these two observation modes, as they can obtain the image information of both modes in one image. We calibrated an appropriate proportion for simultaneous illumination with the light required for WLI and CBI. We designed a new illumination spectrum tailored for gastrointestinal examination, achieving their fusion at the optical level. Using a new algorithm that focuses on enhancing specific hemoglobin tissue features, we restored narrow-band image characteristics lost due to the introduction of white light. Our hardware and software innovations not only boost the illumination brightness of the endoscope but also ensure the narrow-band feature details of the image. To evaluate the reliability and safety of the new endoscopic system, we conducted a series of tests in line with relevant international standards and validated the design parameters. For clinical trials, we collected a total of 256 sets of images, each set comprising images of the same lesion location captured using WLI, CBI, and our proposed method. We recruited four experienced clinicians to conduct subjective evaluations of the collected images. The results affirmed the significant advantages of our method. We believe that the novel endoscopic system we introduced has vast potential for clinical application in the future.
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Potassium-sulfur (K-S) batteries are severely limited by the sluggish kinetics of the solid-phase conversion of K2S3/K2S2 to K2S, the rate-determining and performance-governing step, which urgently requires a cathode with facilitated sulfur accommodation and improved catalytic efficiency. To this end, we leverage the orbital-coupling approach and herein report a strong d-π coupling catalytic configuration of single-atom Co anchored between two alkynyls of graphdiyne (Co-GDY). The d-π orbital coupling of the Co-C4 moiety fully redistributes electrons two-dimensionally across the GDY, and as a result, drastically accelerates the solid-phase K2S3/K2S2 to K2S conversion and enhances the adsorption of sulfur species. Applied as the cathode, the S/Co-GDY delivered a record-high rate performance of 496.0 mAh g-1 at 5 A g-1 in K-S batteries. In situ and ex situ characterizations coupling density functional theory (DFT) calculations rationalize how the strong d-π orbital coupling of Co-C4 configuration promotes the reversible solid-state transformation kinetics of potassium polysulfide for high-performance K-S batteries.
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Engineering isolated metal sites resembling the primary coordination sphere of metallocofactors enables atomically dispersed materials as promising nanozymes. However, most existing nanozymes primarily focus on replicating specific metallocofactors while neglecting other supporting cofactors within active pockets, leading to reduced electron transfer (ET) efficiency and thus inferior catalytic performances. Herein, we report a metal-organic framework UiO-67 nanozyme with atomically dispersed iron sites, which involves multiple tailored enzyme-like nanocofactors that synergistically drive the ET process for enhanced peroxidase-like catalysis. Among them, the linker-coupled atomic iron site plays a critical role in substrate activation, while bare linkers and zirconia nodes facilitate the ET efficiency of intermediates. The synergy of three nanocofactors results in a 4.29-fold enhancement compared with the single effort of isolated metal site-based nanocofactor, holding promise in immunoassay for sensitive detection of chlorpyrifos. This finding opens a new way for designing high-performance nanozymes by harmonizing various nanocofactors at the atomic and molecular scale.
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Oxirredutases , Peroxidase , Peroxidases , Ferro/química , CatáliseRESUMO
Water splitting (or, water electrolysis) is considered as a promising approach to produce green hydrogen and relieve the ever-increasing energy consumption as well as the accompanied environmental impact. Development of high-efficiency, low-cost practical water-splitting systems demands elegant design and fabrication of catalyst-loaded electrodes with both high activity and long-life time. To this end, dimensional engineering strategies, which effectively tune the microstructure and activity of electrodes as well as the electrochemical kinetics, play an important role and have been extensively reported over the past years. Here, a type of most investigated electrode configurations is reviewed, combining particulate catalysts with 3D porous substrates (aerogels, metal foams, hydrogels, etc.), which offer special advantages in the field of water splitting. It is analyzed the design principles, structural and interfacial characteristics, and performance of particle-3D substrate electrode systems including overpotential, cycle life, and the underlying mechanism toward improved catalytic properties. In particular, it is also categorized the catalysts as different dimensional particles, and show the importance of building hybrid composite electrodes by dimensional control and engineering. Finally, present challenges and possible research directions toward low-cost high-efficiency water splitting and hydrogen production is discussed.