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Influence of alkali metal doping on surface properties and catalytic activity/selectivity of CaO catalysts in oxidative coupling of methane 被引量:5
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作者 V.H.Rane S.T.Chaudhari V.R.Choudhary 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第4期313-320,共8页
Surface properties (viz. surface area, basicity/base strength distribution, and crystal phases) of alkali metal doped CaO (alkali metal/Ca= 0.1 and 0.4) catalysts and their catalytic activity/selectivity in oxidat... Surface properties (viz. surface area, basicity/base strength distribution, and crystal phases) of alkali metal doped CaO (alkali metal/Ca= 0.1 and 0.4) catalysts and their catalytic activity/selectivity in oxidative coupling of methane (OCM) to higher hydrocarbons at different reaction conditions (viz. temperature, 700 and 750 ℃; CH4/O2 ratio, 4.0 and 8.0 and space velocity, 5140-20550 cm^3 ·g^-1·h^-1) have been investigated. The influence of catalyst calcination temperature on the activity/selectivity has also been investigated. The surface properties (viz. surface area, basicity/base strength distribution) and catalytic activity/selectivity of the alkali metal doped CaO catalysts are strongly influenced by the alkali metal promoter and its concentration in the alkali metal doped CaO catalysts. An addition of alkali metal promoter to CaO results in a large decrease in the surface area but a large increase in the surface basicity (strong basic sites) and the C2+ selectivity and yield of the catalysts in the OCM process. The activity and selectivity are strongly influenced by the catalyst calcination temperature. No direct relationship between surface basicity and catalytic activity/selectivity has been observed. Among the alkali metal doped CaO catalysts, Na-CaO (Na/Ca = 0.1, before calcination) catalyst (calcined at 750 ℃), showed best performance (C2+ selectivity of 68.8% with 24.7% methane conversion), whereas the poorest performance was shown by the Rb-CaO catalyst in the OCM process. 展开更多
关键词 oxidative coupling of methane alkali metal doped CaO catalysts basicity/base strength distribution catalytic activity/selectivity
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Human Activity Recognition Using Weighted Average Ensemble by Selected Deep Learning Models
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作者 Waseem Akhtar Mahwish Ilyas +3 位作者 Romana Aziz Ghadah Aldehim Tassawar Iqbal Muhammad Ramzan 《Computer Modeling in Engineering & Sciences》 2026年第2期971-989,共19页
Human Activity Recognition(HAR)is a novel area for computer vision.It has a great impact on healthcare,smart environments,and surveillance while is able to automatically detect human behavior.It plays a vital role in ... Human Activity Recognition(HAR)is a novel area for computer vision.It has a great impact on healthcare,smart environments,and surveillance while is able to automatically detect human behavior.It plays a vital role in many applications,such as smart home,healthcare,human computer interaction,sports analysis,and especially,intelligent surveillance.In this paper,we propose a robust and efficient HAR system by leveraging deep learning paradigms,including pre-trained models,CNN architectures,and their average-weighted fusion.However,due to the diversity of human actions and various environmental influences,as well as a lack of data and resources,achieving high recognition accuracy remain elusive.In this work,a weighted average ensemble technique is employed to fuse three deep learning models:EfficientNet,ResNet50,and a custom CNN.The results of this study indicate that using a weighted average ensemble strategy for developing more effective HAR models may be a promising idea for detection and classification of human activities.Experiments by using the benchmark dataset proved that the proposed weighted ensemble approach outperformed existing approaches in terms of accuracy and other key performance measures.The combined average-weighted ensemble of pre-trained and CNN models obtained an accuracy of 98%,compared to 97%,96%,and 95%for the customized CNN,EfficientNet,and ResNet50 models,respectively. 展开更多
关键词 Artificial intelligence computer vision deep learning RECOGNITION human activity classification image processing
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MOF encapsulation derived slow-release oxygen species to enhance the activity and selectivity of methane selective oxidation:A transient DRIFTs Study
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作者 Ke-Xin Li Hao Yuan +1 位作者 Ralph T.Yang Zhun Hu 《Chinese Journal of Catalysis》 2025年第11期202-214,共13页
The methane selective oxidation was a"holy grail"reaction.However,peroxidation and low selectivity limited the application.Herein,we combined three Au contents with TiO_(2)in both encapsulation(xAu@TiO_(2))a... The methane selective oxidation was a"holy grail"reaction.However,peroxidation and low selectivity limited the application.Herein,we combined three Au contents with TiO_(2)in both encapsulation(xAu@TiO_(2))and surface-loaded(xAu/TiO_(2))ways by MOF derivation strategy,reported a catalyst 0.5Au@TiO_(2)exhibited a CH_(3)OH yield of 32.5μmol·g^(-1)·h^(-1)and a CH_(3)OH selectivity of 80.6%under catalytic conditions of only CH_(4),O_(2),and H_(2)O.Mechanically speaking,the catalytic activity was controlled by both electron-hole separation efficiency and core-shell structure.The interfacial contact between Au nanoparticles and TiO_(2)in xAu@TiO_(2)and xAu/TiO_(2)induced the formation of oxygen vacancies,with 0.5 Au content showing the highest oxygen vacancy concentration.At the same Au content,xAu@TiO_(2)generated more oxygen vacancies than xAu/TiO_(2).The oxygen vacancy acted as an effective electron cold trap,which enhanced the photogenerated carrier separation efficiency and thereby improved the catalytic activity.In-situ DRIFTs revealed that the isolated OH(non-hydrogen bond adsorption)were key species for the methane selective oxidation,playing a role in the activation of CH_(4)to^(*)CH_(3).However,an overabundance of isolated OH led to severe overoxidation.Fortunately,the core-shell structure over xAu@TiO_(2)provided a slow-release environment for isolated OH through the intermediate state of^(*)OH(hydrogen bond adsorption)to balance the formation rate and consumption rate of isolated OH,doubling the methanol yield and increasing the>29%selectivity.These results showed a new strategy for the control of the overoxidation rate via a strategy of MOF encapsulation followed by pyrolytic derivation for methane selective oxidation. 展开更多
关键词 Methane selective oxidation Metal-organic framework derived Reactive oxygen species modulation Hydrogen bonded adsoprotion hydroxyl groups
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Synthesis,structural characterization,electrocatalytic proton reduction,and fungicidal activity of thiazole‑containing di‑iron complexes
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作者 JIANG Chengyu LIU Xufeng 《无机化学学报》 北大核心 2026年第2期355-364,共10页
This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the correspo... This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the corresponding ester[Fe_(2)(CO)_(6)(μ‑tedt)](2),where tedt=SCH_(2)CH(CH_(2)OOC(5‑C_(3)HNSCH_(3)))S.Further reactions of complex 2 with tri(ptolyl)phosphine(tp)or tris(4‑fluorophenyl)phosphine(fp)gave the phosphine‑substituted derivatives[Fe_(2)(CO)_(5)(tp)(μ‑tedt)](3)and[Fe_(2)(CO)_(5)(fp)(μ‑tedt)](4).The structures of the newly prepared complexes were elucidated by elemental analysis,NMR,IR,and X‑ray photoelectron spectroscopy.Moreover,single‑crystal X‑ray diffraction analysis confirmed their molecular structures,showing that they contain a di‑iron core ligated by a bridged dithiolate bearing a thiazole moiety and terminal carbonyls.The electrochemical and electrocatalytic proton reduction were probed by cyclic voltammetry,revealing that three complexes can catalyze the reduction of protons to H_(2) under the electrochemical conditions.For comparison,complex 4 possessed the best efficiency with a turnover frequency of 23.5 s^(-1)at 10 mmol·L^(-1)HOAc concentration.In addition,the fungicidal activity of these complexes was also investigated in this study.CCDC:2477511,2;2477512,3;2477513,4. 展开更多
关键词 THIAZOLE di‑iron complex crystal structure electrocatalytic proton reduction fungicidal activity
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Silver chloride/chitosan‑based chloramine nanohybrid with excellent antibacterial activity:Design and structure characterization as well as Ag^(+)‑Cl^(-)synergistic antibacterial effect
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作者 ZHANG Xinzhe XU Jiarong +4 位作者 GAO Mochou LIU Yage ZHAO Yanbao CUI Jingzeng ZOU Xueyan 《无机化学学报》 北大核心 2026年第2期428-438,共11页
Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticle... Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticles were chlorinated by NaClO solution to get AgCl@SiO_(2)/CTS‑based chloramine nano‑hybrid materials,denoted as AgCl@SiO_(2)/CTS‑Cl.A transmission electron microscope was used to observe the morphology of the as‑prepared samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.At the same time,an X‑ray diffractometer and an infrared spectroscope were utilized to characterize their crystal and chemical structures.Besides,ζpotentials were measured to elucidate the surface modification of AgCl nanoparticles by—NH_(2),the antibacterial mechanism of AgCl@SiO_(2)/CTS‑Cl was investigated by scanning electron microscopy,and Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were used as the to‑be‑tested strains to evaluate the antimicrobial activity of samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.Findings demonstrate that sample AgCl@SiO_(2)/CTS exhibits a chain‑like structure ascribed to the interaction between—NH_(2),and each AgCl@SiO_(2)/CTS hybrid nanoparticle contains several AgCl cores.In the meantime,sample AgCl@SiO_(2)/CTS‑Cl exhibits excellent antibacterial activity against E.coli and S.aureus,which is attributed to the synergistic antibacterial effect of Ag^(+)and Cl^(-).Sample AgCl@SiO_(2)/CTS‑Cl with a dosage of 640.00μg·mL^(-1) could completely kill the two kinds of tested bacteria in 12 h of incubation;it retains a high antibacterial efficiency even after 10 cycles of antibacterial tests. 展开更多
关键词 AgCl@SiO_(2)/CTS‑Cl hybrid nanoparticle synergistic effect antibacterial activity
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Preoperative butyrylcholinesterase activity and risk of postoperative delirium:A meta-analysis
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作者 Yuan-Li Qiu Cheng Song +1 位作者 Cui-Wan Huang Wei-Gang Shen 《World Journal of Psychiatry》 2026年第1期385-399,共15页
BACKGROUND Postoperative delirium(POD)is a common and serious complication in surgical patients,particularly older adults.Alterations in cholinergic function have been implicated in its pathophysiology.AIM To evaluate... BACKGROUND Postoperative delirium(POD)is a common and serious complication in surgical patients,particularly older adults.Alterations in cholinergic function have been implicated in its pathophysiology.AIM To evaluate the association between preoperative serum cholinesterase(ChE)activity—specifically butyrylcholinesterase(BuChE)and acetylcholinesterase(AChE)—and the risk of POD in adult surgical patients in a meta-analysis.METHODS A systematic search was conducted in PubMed,EMBASE,and Web of Science up to March 28,2025 for studies reporting preoperative serum BuChE or AChE activity in relation to subsequent POD incidence.Standardized mean differences(SMDs)and odds ratios(ORs)with 95%confidence intervals(CIs)were pooled using random-effects models.Subgroup and sensitivity analyses were performed based on follow-up duration and analytic models.RESULTS Thirteen studies(n=2730 patients)were included.Patients who developed POD had significantly lower preoperative BuChE activity than those who did not(SMD=-0.28;95%CI:-0.39 to-0.16;I^(2)=18%).Higher BuChE activity was associated with a reduced risk of POD(OR per 100 unit increment=0.97;95%CI:0.95-0.99;I2=0%).In contrast,pooled AChE activity did not differ significantly between POD and non-POD groups(SMD=-0.25;95%CI:-0.53 to 0.03;P=0.08;I^(2)=80%),and the ORs per 1 unit increment in AChE activity were not statistically significant(OR=0.98;95%CI:0.95-1.01).CONCLUSION Lower preoperative serum BuChE activity is associated with an increased risk of POD in adults undergoing surgery.BuChE activity may serve as a potential preoperative biomarker for POD risk stratification. 展开更多
关键词 ACETYLCHOLINESTERASE BUTYRYLCHOLINESTERASE activity Postoperative delirium META-ANALYSIS
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Study on the Extraction of Flavonoids from Hylocereus undatus(Haw.)Britton&Rose and Their Antioxidant Activity
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作者 Zhao LIU Deyun MA +1 位作者 Rimeng CHEN Meijiao MO 《Agricultural Biotechnology》 2026年第1期65-69,共5页
[Objectives]This study was conducted to investigate the extraction process,content determination,and antioxidant properties of flavonoids from Hylocereus undatus(Haw.)Britton&Rose.[Methods]Using H.undatus as the r... [Objectives]This study was conducted to investigate the extraction process,content determination,and antioxidant properties of flavonoids from Hylocereus undatus(Haw.)Britton&Rose.[Methods]Using H.undatus as the raw material,the effects of ethanol concentration,ultrasonic temperature,time,and solid-to-liquid ratio on the total flavonoid yield were investigated through single-factor and orthogonal experiments.[Results]All factors had a significant effect on the yield.The optimized conditions were determined as follows:ethanol concentration 75%,ultrasonic temperature 60℃,ultrasonic time 30 min,and solid-to-liquid ratio 1:50(g/ml).Under these conditions,the total flavonoid yield reached 3.08%.Evaluation of antioxidant activity revealed that the extract exhibited superior scavenging rates against both DPPH and hydroxyl radicals compared with the standard reference compound BHT.[Conclusions]This study holds significant importance for elucidating the pharmacological mechanisms of flavonoids in H.undatus and for expanding their application in medicine and health products. 展开更多
关键词 Hylocereus undatus FLAVONOIDS Antioxidant activity
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Conductive materials change the composition and activity of butyrate-degrading enrichment cultures with hydrogen as the main electron shuttle
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作者 Cátia S.N Braga João C.Sequeira +5 位作者 M.SaloméDuarte Gilberto Martins Inês A.C.Pereira c Luciana Pereira M.Madalena Alves Andreia F.Salvador 《Journal of Environmental Sciences》 2026年第1期624-634,共11页
Conductive materials(CM)can improve methane production(MP)efficiency in many methanogenic systems.However,several types of CM exist,and there are uncertainties regarding whether they all improve MP efficiency to the s... Conductive materials(CM)can improve methane production(MP)efficiency in many methanogenic systems.However,several types of CM exist,and there are uncertainties regarding whether they all improve MP efficiency to the same extent and modulate microbial communities in a similar way.To investigate that,different microbial enrichments with and without activated carbon(AC),magnetite(Mag),and zeolites(Zeo)(at 0.5 g/L)were developed.MP profiles and microbial composition changes were compared among enrichments.The behavior of all enrichments was different,although the initial inoculum sludge was the same.Lag phase duration was lower in AC enrichment,while the complete conversion of butyrate to methane was faster in Mag enrichment.Syntrophomonas was the most abundant bacterial genus in all enrichments,but changes in the methanogenic community were evident.Acetoclastic methanogens were more diverse in Mag enrichment,with microorganisms assigned to Methanosarcina and Methanothrix gener1,but Methanothrix was the only acetoclastic methanogen in the other enrichments.On the other hand,different species of hydrogenotrophic methanogens prevailed in distinct enrichments.The metatranscriptomics results revealed that the dominant mechanism of interspecies electron transfer in the AC enrichment utilized hydrogen as the electron carrier,and no evidences of direct interspecies electron transfer(DIET)could be found.These results showed how different CM modulate microbial communities and affect MP efficiency through mechanisms that do not necessarily involve DIET or mediation via CM. 展开更多
关键词 BUTYRATE METHANE Anaerobic enrichments activated carbon MAGNETITE Zeolites
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Physical activity and exercise within the context of obesity treatment:Enhancing health beyond weight loss
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作者 John M.Jakicic Christian E.Behrens +7 位作者 Sarah E.Deemer Bethany Forseth Christos S.Katsanos Brett S.Nickerson Wagner L.Prado Xuewen Wang Landon S.Deru Renee J.Rogers 《Journal of Sport and Health Science》 2026年第2期31-40,共10页
Overweight and obesity are significant public health concerns worldwide due to their association with many chronic health conditions.This has resulted in the development of various interventions focused on weight loss... Overweight and obesity are significant public health concerns worldwide due to their association with many chronic health conditions.This has resulted in the development of various interventions focused on weight loss to reduce the associated health burden.Physical activity is an important lifestyle behavior associated with enhanced health.Evidence supports that many of the benefits of physical activity are realized independent of initial weight status or whether weight loss is achieved,with some benefits additive to what is achieved with weight loss alone.These benefits include enhanced cardiometabolic,brain,cognitive and psychological health,and others.Moreover,in adults with overweight or obesity,physical activity has independent effects on cardiorespiratory fitness,muscular strength,physical function,and mobility.There are also benefits to body composition,with physical activity improving the quality of key tissues,such as skeletal muscle,which may not occur with diet-induced weight loss.Therefore,physical activity is an important public health target for adults with overweight or obesity to provide a wide range of health benefits that extend beyond those of weight loss alone.However,physical activity recommendations and programming efforts should consider the unique characteristics of adults with overweight or obesity to be most effective,and should support a focus on mobility,physical function,and other health outcomes. 展开更多
关键词 Physical activity EXERCISE OBESITY Body composition Health risk
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Abnormal regional spontaneous brain activity in major depressive disorder with obesity comorbidity:A resting-state functional magnetic resonance imaging study
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作者 Xiao-Fang Hou Bo-Hui Mei +10 位作者 Xia Wang Fu-Tao Zhao Lei He Qian-Yu Chen Chen Zang Chong Wang Yu-Feng Tang Xiao-Xin Li Hui-Fang Zhang Na Wang Bing Cao 《World Journal of Psychiatry》 2026年第1期335-345,共11页
BACKGROUND Major depressive disorder(MDD)and obesity(OB)are bidirectionally comorbid conditions with common neurobiological underpinnings.However,the neurocognitive mechanisms of their comorbidity remain poorly unders... BACKGROUND Major depressive disorder(MDD)and obesity(OB)are bidirectionally comorbid conditions with common neurobiological underpinnings.However,the neurocognitive mechanisms of their comorbidity remain poorly understood.AIM To examine regional abnormalities in spontaneous brain activity among patients with MDD-OB comorbidity.METHODS This study adopted a regional homogeneity(ReHo)analysis of resting-state functional magnetic resonance imaging.The study included 149 hospital patients divided into four groups:Patients experiencing their first episode of drug-naive MDD with OB,patients with MDD without OB,and age-and sex-matched healthy individuals with and without OB.Whole-brain ReHo analysis was conducted using SPM12 software and RESTplus toolkits,with group comparisons via ANOVA and post-hoc tests.Correlations between ReHo values and behavioral measures were examined.RESULTS ANOVA revealed significant whole-brain ReHo differences among the four groups in four key regions:The left middle temporal gyrus(MTG.L),right cuneus,left precuneus,and left thalamus.Post-hoc analyses confirmed pairwise differences between all groups across these regions(P<0.05).OB was associated with ReHo alterations in the MTG.L,right cuneus,and left thalamus,whereas abnormalities in the precuneus suggested synergistic pathological mechanisms between MDD and OB.Statistically significant correlations were found between the drive and fun-seeking dimensions of the behavioral activation system,as well as behavioral inhibition and the corresponding ReHo values.CONCLUSION Our findings provide novel evidence for the neuroadaptive mechanisms underlying the MDD-OB comorbidity.Further validation could lead to personalized interventions targeting MTG.L hyperactivity and targeting healthy food cues. 展开更多
关键词 Neuroimage COMORBIDITY Brain activity OBESITY Major depression Regional spontaneous
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Oxygenation-driven multimodal photoacoustic/ultrasonic imaging enhances evaluation of enthesitis disease activity in psoriatic arthritis
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作者 Rui Zhang Fan Yang +8 位作者 Chenyang Zhao Ming Wang Yan Zhang Fang Yang Lei Zhu Jianchu Li Yuxin Jiang Xiaomei Leng Meng Yang 《Journal of Innovative Optical Health Sciences》 2026年第1期126-138,共13页
Conventional ultrasound(US)evaluation of enthesitis in psoriatic arthritis(PsA)is limited by its inability to quantify metabolic alterations such as hypoxia,a key driver of disease activity.We introduce an oxygenation... Conventional ultrasound(US)evaluation of enthesitis in psoriatic arthritis(PsA)is limited by its inability to quantify metabolic alterations such as hypoxia,a key driver of disease activity.We introduce an oxygenation-integrated multimodal photoacoustic/ultrasound(PA/US)imaging framework designed to quantify entheseal oxygen saturation(SO_(2))for assessing entheseal disease activity in PsA.In this cross-sectional study,25 PsA patients underwent bilateral PA/US imaging of 12 entheses,where ultrasound lesions were scored using the Outcome Measures in Rheumatology scoring system,and PA-derived SO_(2) levels,quantified via dual-wavelength PA imaging,were classified into hyperoxia or hypoxia groups using k-means clustering.This approach provides metabolic insights complementary to conventional ultrasonic assessment.A composite score integrating hypoxia with US parameters was validated against clinical disease activity indices(Disease Activity Score 28-C-reactive protein,DAS28-CRP;Disease Activity Index for Psoriatic Arthritis,DAPSA).Among 300 entheses,103(34.3%)exhibited PA positivity,with 40(38.8%)classified as hypoxia.Hypoxia scores independently predicted DAS28-CRP(β=0.618,p=0.001)and DAPSA(β=0.612,p<0:001).The hypoxia-optimized PAUS score demonstrated superior correlation with disease activity indices compared to conventional US(DAS28-CRP:r=0.615,p=0.001 versus r=0.474,p=0.017;DAPSA:r=0.743,p<0:001 versus r=0.567,p=0.003),alongside superior diagnostic accuracy for minimal disease activity(area under the curve,AUC 0.776 versus 0.614,p=0.008)and low disease activity(AUC 0.853 versus 0.772,p=0.009).This multimodal scoring system enhances the stratification of PsA disease activity by providing unique metabolic insights,offering a potential tool for therapeutic monitoring and guiding treat-to-target strategies. 展开更多
关键词 Photoacoustic imaging oxygen saturation ENTHESIS disease activity evaluation
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Redefining selectivity paradigms in electrochemical nitrogen reduction reaction on confined dual-atom catalysts
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作者 Nana Hu Xingshuai Lv +2 位作者 Guobo Chen Thomas Frauenheim Liangzhi Kou 《Science China Materials》 2026年第3期1719-1728,共10页
The premature decay of electrochemical nitrogen reduction reaction(eNRR)performance at low electrode potentials remains a major obstacle to practical applications,which is primarily attributed to the competition from ... The premature decay of electrochemical nitrogen reduction reaction(eNRR)performance at low electrode potentials remains a major obstacle to practical applications,which is primarily attributed to the competition from the hydrogen evolution reaction(HER).A new paradigm capable of transcending current selectivity constraints is urgently required to advance eNRR toward industrial implementation.In this work,we propose two practical selectivity descriptors(ΔΔG andΔU)based on a systematic investigation of the potential-dependent competition between eNRR and HER on confined dual-atom catalysts.The descriptorΔΔG(G_(N_(2))-ΔG_(H))identifies the potential range where N_(2)adsorption dominates over H adsorption,whileΔU(U_(cross)-U_(eNRR))specifies the potential range to trigger direct eNRR,offering a quantitative benchmark for rational catalyst design.Ideal catalysts should maintain N_(2)-preferential adsorption across a broad potential window to facilitate direct eNRR.Guided by this insight,we demonstrate that confined dual-atom configurations with optimized interatomic distances can simultaneously achieve both overwhelming N_(2)adsorption and sufficient activation,thereby overcoming the conventional selectivity limitations.This strategy enables ammonia synthesis with industrially relevant production rates and current density even at elevated potentials.Our mechanistic insights not only elucidate the root causes of performance limitations in eNRR but also offer a rational design framework for developing high-performance catalysts across a broad range of electrochemical transformations. 展开更多
关键词 electrochemical nitrogen reduction selectivity confined dual-atom catalysts diporphyrins constant-potential/solvation model
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Sodium alginate-based photothermal film:preparation,antibacterial activity,and application for preservation of Kyoho grapes
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作者 Zihan Hou Yunxiao Xia +4 位作者 Yuan Sun Ming Yang Lingling Wang Weizhuo Xu Xu Zhao 《Journal of Future Foods》 2026年第6期1176-1187,共12页
The photothermal effect enhances the antibacterial activity by generating localized heat that disrupts microbial cells,leading to increased bacterial inactivation.The objective of this study was to develop and evaluat... The photothermal effect enhances the antibacterial activity by generating localized heat that disrupts microbial cells,leading to increased bacterial inactivation.The objective of this study was to develop and evaluate the antibacterial and photothermal applications of polydopamine-berberine nanoparticles(PDA-BBR-NPs),incorporating them into a sodium alginate matrix for food preservation.The self-assembled PDA-BBR-NPs were synthesized using a solution oxidation method and characterized by scanning electron microscopy,Fourier transform infrared spectroscopy,and nanoparticle size analysis.The results demonstrated that PDA-BBR-NPs were uniform spheres with an average diameter of 177.1 nm.Drug loading and encapsulation efficiency tests showed that the optimal formulation had a drug loading capacity of 48.4%and an encapsulation efficiency of 84.70%.Antibacterial activity against Escherichia coli and Staphylococcus aureus was evaluated using the dilution coating plate method,showing an inhibition rate of over 98%.Photothermal testing under 808 nm near-infrared irradiation revealed a maximum photothermal conversion efficiency of 32.65%.To assess the practical application of the nanoparticles,they were incorporated into a sodium alginate-based coating for the preservation of Kyoho grapes.Key parameters such as weight loss rate,pH,titratable acidity,and soluble solids content were monitored over a 12-day storage period at room temperature.The PDA-BBR-near-infrared spectroscopy-treated group exhibited significantly reduced weight loss rate(6.08%lower than the control group)and a slower decrease in pH.The coating effectively inhibited microbial activity and extended the shelf life of the grapes by 3-6 days compared to the control group.These findings demonstrated the potential of PDA-BBR-NPs to enhance the preservation of fresh produce through their combined antibacterial and photothermal effects,offering a promising method for extending fruit shelf life. 展开更多
关键词 POLYDOPAMINE BERBERINE Antibacterial activity Photothermal properties Sodium alginate Food packaging
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Overcoming temporal and sequential data challenges in electroencephalography for harmful brain activity classification
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作者 Shabir Hussain Maryam Ghaffar Ruman Babar 《Biomedical Engineering Communications》 2026年第2期4-14,共11页
Background:Early detection of harmful brain activity in critically ill patients using electroencephalography(EEG)is vital for timely and effective clinical intervention.Automating EEG analysis with deep learning techn... Background:Early detection of harmful brain activity in critically ill patients using electroencephalography(EEG)is vital for timely and effective clinical intervention.Automating EEG analysis with deep learning techniques holds significant promise for enhancing diagnostic efficiency and accuracy.Methods:We implemented EfficientNetB2,which leverages convolutional neural networks with a novel Temporal Squeeze-and-Excitation module to capture temporal EEG features,and WaveNet,a sequential model designed to effectively model temporal dependencies in EEG data using dilated causal convolutions and temporal self-attention.Both models were trained and evaluated using a publicly available EEG dataset,with performance assessed via 4-fold cross-validation and a step-wise learning rate reduction strategy.Results:Our results demonstrate a significant reduction in training loss from 0.6459 to 0.3055 and validation loss from 0.9602 to 0.5719 over six epochs.Consistent improvements were observed across cross-validation folds,highlighting the robustness of the models.Additionally,ensemble learning of the two architectures further enhanced classification performance.Conclusion:This comparative analysis sheds light on the strengths and limitations of EfficientNetB2 and WaveNet for automated harmful brain activity detection in EEG signals.The findings contribute to the advancement of reliable and efficient deep learning models,paving the way for their clinical application in managing critically ill patients. 展开更多
关键词 ELECTROENCEPHALOGRAPHY harmful brain activity EfficientNetB2 ensemble learning WaveNet4
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An Improved Machine Learning Model for Screening and Activity Prediction of Receptor Tyrosine Kinase
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作者 Huanghui Xia Huangzhi Xia Jianzhong Huang 《Journal of Bionic Engineering》 2026年第1期488-523,共36页
Aberrant activation of Receptor Tyrosine Kinases(RTKs)is a well-established trigger of tumorigenesis,and the over-use of RTK inhibitors often leads to drug resistance and tumor recurrence.While current Drug-Target Int... Aberrant activation of Receptor Tyrosine Kinases(RTKs)is a well-established trigger of tumorigenesis,and the over-use of RTK inhibitors often leads to drug resistance and tumor recurrence.While current Drug-Target Interaction(DTI)prediction methods(including those based on heterogeneous information networks)have shown promise,they remain limited in their ability to fully capture the nature of DTIs and often lack interpretability.To overcome these limitations,this study introduces a novel hybrid optimization model termed MDBO-RF,which integrates a Modified Dung Beetle Optimizer(MDBO)with Random Forest(RF).The key innovation lies in the enhancement of the DBO algorithm through a quaternion-based learning mechanism and the Cauchy mutation strategy,specifically designed to overcome the slow convergence and susceptibility to local optima that plague traditional metaheuristic algorithms used for hyperparameter tuning.The model leverages commonly used molecular descriptors to enhance the prediction of Tyrosine Kinase(TK)inhibitory activity and enable efficient compound screening.Our results demonstrate that MDBO-RF achieves a 3.41%increase in prediction accuracy compared to the standard RF model and outperforms several other contemporary machine learning approaches.The model effectively streamlines the RTK inhibitor screening process by improving prediction accuracy in multi-target competitive binding scenarios and reducing false-positive screening due to off-target effects.This work underscores the value of hybrid optimization strategies in bioinformatics and provides a robust,interpretable tool for accelerating drug discovery. 展开更多
关键词 Receptor tyrosine kinase Tumor resistance Inhibitor activity assessment Random forest MDBO-RF
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Breast cancer stem cell activity driven by ME18D gene expression in the tumor microenvironment
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作者 De-Yang Guo Zhang-Yi Liu Qian-Chuan Yi 《World Journal of Stem Cells》 2026年第1期49-65,共17页
BACKGROUND Breast cancer is one of the most prevalent malignancies affecting women worldwide,with approximately 2.3 million new cases diagnosed annually.Breast cancer stem cells(BCSCs)play pivotal roles in tumor initi... BACKGROUND Breast cancer is one of the most prevalent malignancies affecting women worldwide,with approximately 2.3 million new cases diagnosed annually.Breast cancer stem cells(BCSCs)play pivotal roles in tumor initiation,progression,metastasis,therapeutic resistance,and disease recurrence.Cancer stem cells possess selfrenewal capacity,multipotent differentiation potential,and enhanced tumorigenic activity,but their molecular characteristics and regulatory mechanisms require further investigation.AIM To comprehensively characterize the molecular features of BCSCs through multiomics approaches,construct a prognostic prediction model based on stem cellrelated genes,reveal cell-cell communication networks within the tumor microenvironment,and provide theoretical foundation for personalized treatment strategies.METHODS Flow cytometry was employed to detect the expression of BCSC surface markers(CD34,CD45,CD29,CD90,CD105).Transcriptomic analysis was performed to identify differentially expressed genes.Least absolute shrinkage and selection operator regression analysis was utilized to screen key prognostic genes and construct a risk scoring model.Single-cell RNA sequencing and spatial transcriptomics were applied to analyze tumor heterogeneity and spatial gene expression patterns.Cell-cell communication network analysis was conducted to reveal interactions between stem cells and the microenvironment.RESULTS Flow cytometric analysis revealed the highest expression of CD105(96.30%),followed by CD90(68.43%)and CD34(62.64%),while CD29 showed lower expression(7.16%)and CD45 exhibited the lowest expression(1.19%).Transcriptomic analysis identified 3837 significantly differentially expressed genes(1478 upregulated and 2359 downregulated).Least absolute shrinkage and selection operator regression analysis selected 10 key prognostic genes,and the constructed risk scoring model effectively distinguished between high-risk and low-risk patient groups(P<0.001).Single-cell analysis revealed tumor cellular heterogeneity,and spatial transcriptomics demonstrated distinct spatial expression gradients of stem cell-related genes.MED18 gene showed significantly higher expression in malignant tissues(P<0.001)and occupied a central position in cell-cell communication networks,exhibiting significant correlations with tumor cells,macrophages,fibroblasts,and endothelial cells.CONCLUSION This study comprehensively characterized the molecular features of BCSCs through multi-omics approaches,identified reliable surface markers and key regulatory genes,and constructed a prognostic prediction model with clinical application value. 展开更多
关键词 Breast cancer stem cells Surface markers TRANSCRIPTOMICS Least absolute shrinkage and selection operator regression Prognostic model
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Quantitative analysis of the relative tectonic activity of the Almus fault zone,Tokat,Türkiye
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作者 Serkan GÜRGÖZE 《Journal of Mountain Science》 2026年第1期29-48,共20页
The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents t... The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents the integration of morphometric indices to quantitatively assess the spatial variation of tectonic activity along the AFZ.The AFZ is an active fault with both strike-slip and normal fault components and consists of two main branches,Mercimekdağı-Çamdere Fault(MÇF)and Tokat Fault(TF)segments.This study aims to assess the relative tectonic activity of the AFZ using various morphometric indices,based on a 10 m resolution DEM,with the aid of ArcGIS and MATLAB software.For this purpose,morphometric indices such as hypsometric integral(HI:0.35-0.65),mountain front sinuosity(Smf:1.3-1.44),valley floor width-height ratio(Vf:0.15-2.28),asymmetry factor(AF:23-77),drainage basin shape(Bs:1.13-6.10)and normalized steepness index(ksn:1-498)were applied to 53 drainage basins.When the Smf and mean Vf indices results were evaluated,it was calculated that the uplift ratio of the region was more than 0.5 mm/yr.The spatial distribution of the relative tectonic activity(Iat)of the area was revealed by combining the obtained morphometric indices analysis results.According to the Iat result,it was concluded that the MercimekdağıÇamdere Fault and Tokat Fault segments have high tectonic activity,but the Mercimekdağı-Çamdere Fault segment has higher tectonic activity.The results obtained were also confirmed by field observations.This research provides valuable information for the evaluation of tectonic activity in drainage systems controlled by splay faults. 展开更多
关键词 Almus Fault Zone Morphometric indices Relative tectonic activity Tokat Türkiye
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Molecular Fingerprinting of Three Ex-Situ Cultivated Populations of Acalypha gaumeri Pax&K.Hoffm(Female and Male)and Evaluation of Their Antifungal Activity Against Phytopathogens
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作者 Christian Pérez-Chablé Daisy Pérez-Brito +3 位作者 Anuar Magaña-Alvarez Jairo Cristóbal-Alejo Irma L.Medina-Baizabal Marcela Gamboa-Angulo 《Phyton-International Journal of Experimental Botany》 2026年第2期36-54,共19页
Acalypha gaumeri(Euphorbiaceae)is the only endemic species of the genus in the Yucatan Peninsula.It is dioecious and has antifungal properties against various phytopathogens.In the present study,molecular identificati... Acalypha gaumeri(Euphorbiaceae)is the only endemic species of the genus in the Yucatan Peninsula.It is dioecious and has antifungal properties against various phytopathogens.In the present study,molecular identification of A.gaumeri was performed using the rbcL region,confirming its belonging to the Acalypha genus.Its genetic diversity was evaluated using 10 SPAR markers(ISSR and DAMD)from 60 individuals collected from female and male plants of the Kiuic,Tinum and Yaxcaba ex-situ populations.The results showed a high level of genetic polymorphism(PIC=0.980)and significant differences among the populations.Ethanol and aqueous extracts from leaves,stems,and roots of both genders and three populations were evaluated against three phytopathogenic fungi.Only the ethanol extracts of the roots showed inhibitory antifungal activity,whereas Kiuic and Tinum,both male and female individuals,showed inhibitory effects at 1000μg/mL against the three pathogens.The ethanol extract of the female flowering plant of Kiuic showed activity at minimum inhibitory concentrations of 250μg/mL against Alternaria chrysanthemi CICY004 and 500μg/mL against Colletotrichum gloeosporioides CICY002 and Penicillium oxalicum ITC25.Chromatographic profile of the ethanol extracts confirmed the presence of alkaloidal components in the ex-situ cultivated plants,which were analyzed by HPLC.The results revealed that the peaks at T_(R) of 7.60,7.88,and 8.49 min were the most abundant components(9.95%-21.93%),with differences between female and male plants of the three populations.This research confirms that A.gaumeri cultivated and genetically characterized is a potential raw material to develop an eco-friendly product for the control of fungal diseases in crops. 展开更多
关键词 Acalypha gaumeri antifungal activity alkaloidal compounds eco-friendly crop protection genetic diversity phytopathogenic fungi
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Insight into plasma-catalytic CO_(2)methanation mechanism at Ni-Ov-Ni and basic sites in NaF-modified Ni/La_(2)O_(3)catalysts with excellent activity
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作者 Cenxin Ma Jin Zhang +2 位作者 Ke Yin Ziwei Wang Daiqi Ye 《Journal of Energy Chemistry》 2026年第1期170-182,I0005,共14页
Large-scale CO_(2)emissions have exacerbated the greenhouse effect,reinforcing the critical need for efficient CO_(2)mitigation methods.Plasma-catalytic technology enables CO_(2)conversion under mild conditions,especi... Large-scale CO_(2)emissions have exacerbated the greenhouse effect,reinforcing the critical need for efficient CO_(2)mitigation methods.Plasma-catalytic technology enables CO_(2)conversion under mild conditions,especially for CO_(2)methanation(the Sabatier reaction),which has attracted significant attention due to its economic benefits and the potential for safe energy transportation via existing natural gas pipelines.The development of high-performance CO_(2)methanation catalysts remains an ongoing and long-term objective,and there is a lack of adequate in-situ characterization techniques to investigate the mechanisms.This study focuses on the Ni/La_(2)O_(3)(LN)catalyst and introduces two CO_(2)activation strategies through F and Na modifications:the Ni-Ov-Ni site activation with electron transfer from Ni0 under low-power conditions and basic site activation under high-power conditions.The LN-NaF catalysts enhance CO_(2)methanation activity across the entire power range compared to LN,achieving a CO_(2)conversion of 86.3%and CH4 selectivity of 99.4%.Additionally,LN-F(h)reaches a CH4 yield 4.15 times higher than that of LN at low power.Furthermore,in-situ diffuse reflectance infrared Fourier transform(DRIFT)spectroscopy with a self-made reactor are performed under plasma-catalytic conditions to reveal the CO_(2)adsorption and conversion mechanisms,indicating that different dopants(F,Na,and NaF)exhibit promoting effects on different intermediates,resulting in variations in CO_(2)methanation activity.This study provides valuable insights for improving catalyst performance and a thorough comprehension of mechanisms in CO_(2)methanation. 展开更多
关键词 NaF-Ni/La_(2)O_(3)catalysts Ni-Oy-Ni activity site Dual CO_(2)activation sites Plasma-catalytic CO_(2)methanation Plasma-catalytic in-situ DRIFTs
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Unprecedented diphenyl ether hybrids and spiro-diphenyl ether with antioxidant activity from Aspergillus sp.F1-8A associated with toad venom
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作者 Hai-Ying Yu Yu-Wei Huang +1 位作者 Li-Ping Lin Ren-Xiang Tan 《Chinese Chemical Letters》 2026年第2期352-356,共5页
Asplactones A-E(1-5),five unique diphenyl ether hybrids,along with two rare spiro-diphenyl ethers,aspviolaceols A(6)and B(7),were isolated and characterized from Aspergillus sp.F1-8A,an endophytic fungus associated wi... Asplactones A-E(1-5),five unique diphenyl ether hybrids,along with two rare spiro-diphenyl ethers,aspviolaceols A(6)and B(7),were isolated and characterized from Aspergillus sp.F1-8A,an endophytic fungus associated with the parotoid glands of Bufo gargarizans Cantor.Compounds 1-5 represent the first examples of diphenyl ether hybrids fused with unusual moieties,including conjugatedγ-butyrolactone and cyclopentenone.Compounds 6 and 7 are the first known natural spiro-diphenyl ethers,with 6 featuring an uncommon 6/6/6/6-membered carbon skeleton,and 7 possessing a distinct 6/6/6/6/6/6-membered diphenyl ether spiro-heterodimer carbon framework.Structural elucidation was performed using a combination of spectroscopic techniques,X-ray crystallography,and quantum-chemical calculations,and plausible biosynthetic pathways were proposed.Biologically,compounds 1,2,4,6,and 7 exhibited antioxidant activity comparable to or surpassing that of vitamin C in 1,1-diphenyl-2-picrylhydrazyl(DPPH)and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate)(ABTS),and ferric reducing power assays.They also significantly improved cell viability in H2O2-induced oxidative injury assays using A549 cells. 展开更多
关键词 Diphenyl ether hybrids Spiro-diphenyl ethers Γ-BUTYROLACTONE CYCLOPENTENONE ASPERGILLUS Bufo gargarizans Cantor Antioxidant activity
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