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Moderately large amplitude forced vibration of sandwich functionally graded auxetic beams:an analytical approach
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作者 F.M.NASREKANI H.EIPAKCHI 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期99-114,共16页
Sandwich functionally graded(FG)auxetic beams are extensively utilized in aerospace,automotive,and biomedical industries due to their excellent strength-toweight ratio,impact resistance,and tunable mechanical properti... Sandwich functionally graded(FG)auxetic beams are extensively utilized in aerospace,automotive,and biomedical industries due to their excellent strength-toweight ratio,impact resistance,and tunable mechanical properties.The integration of FG materials with auxetic structures enhances their adaptability in advanced engineering applications.However,understanding their dynamic behavior under external excitations is essential for optimal design and structural reliability.Nonlinear interactions in such structures pose significant challenges in vibration analysis,necessitating robust analytical methods.This study presents a closed-form solution for the nonlinear forced vibration analysis of sandwich FG auxetic beams,offering an accurate and efficient method for predicting their dynamic response.The beam consists of two FG face sheets with material properties varying through the thickness and a re-entrant honeycomb auxetic core with an adjustable Poisson's ratio.The governing nonlinear equations of motion are derived using the first-order shear deformation theory(FSDT),the modified Gibson model,and the von Kármán relations,formulated through Hamilton's principle.A closed-form solution is obtained via the Galerkin method and multiple-scale technique.The results demonstrate that FG layers enable control of the overweight and dynamic response amplitude,with positive power law indexes reducing weight.Comparisons with finite element results confirm the accuracy of the proposed formulation. 展开更多
关键词 functionally graded(FG)auxetic beam nonlinear forced vibration closedform solution multiple-scale method first-order shear deformation theory(FSDT)
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Improved Bound of the Fourth Hankel Determinant for a Class of Analytic Functions with Bounded Turnings Involving Cardioid Domain
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作者 Dong GUO Huo TANG +1 位作者 Xi LUO Zongtao LI 《Journal of Mathematical Research with Applications》 2025年第1期39-55,共17页
In the paper,a class of functions with bounded turnings involving cardioid domain,are studied in the region of the unit disc.The bounds of|a_(5)|,|a_(6)|,|a_(7)|and the fourth Hankel determinant are obtained,which are... In the paper,a class of functions with bounded turnings involving cardioid domain,are studied in the region of the unit disc.The bounds of|a_(5)|,|a_(6)|,|a_(7)|and the fourth Hankel determinant are obtained,which are more accurate than those obtained by Srivastava. 展开更多
关键词 analytic functions starlike functions convex functions Schwarz function cardioid domain Hankel determinant
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Holder’s inequalities for a class of analytic functions connected with a certain hybrid-type convolution operator
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作者 H.M.Srivastava Sheza M.El-Deeb 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期443-457,共15页
By using a certain hybrid-type convolution operator,we first introduce a new subclass of normalized analytic functions in the open unit disk.For members of this analytic function class,we then derive several propertie... By using a certain hybrid-type convolution operator,we first introduce a new subclass of normalized analytic functions in the open unit disk.For members of this analytic function class,we then derive several properties and characteristics including(for example)the modified Hadamard products,Holder's inequalities and convolution properties as well as some closure properties under a general family of integral transforms. 展开更多
关键词 analytic functions univalent functions binomial series:hybrid-type convolution operator Holder's inequalities modi ed Hadamard product convolution properties closure properties under integral transforms
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Synthetic metabolic engineering of functional crops:Boosting nutrition and human health 被引量:3
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作者 Nan Chai Jie Xu +12 位作者 Ruixiang Zhang Guangzhou Li Jun Wen Liying Su Yang Xue Tie Li Jialin Liu Dongchang Zeng Jiantao Tan Jiaqi Huang Letian Chen Yao-Guang Liu Qinlong Zhu 《The Crop Journal》 2026年第1期8-21,共14页
A growing global population and the increasing prevalence of diet-related health issues such as“hidden hunger”,obesity,hypertension,and diabetes necessitate a fundamental rethinking of crop design and breeding.Synth... A growing global population and the increasing prevalence of diet-related health issues such as“hidden hunger”,obesity,hypertension,and diabetes necessitate a fundamental rethinking of crop design and breeding.Synthetic metabolic engineering offers a method to modify and redesign metabolic pathways to increase the nutritional value of crops.We summarize recent advances in the biofortification of key nutrients including provitamin A,vitamin C,vitamin B9,iron,zinc,anthocyanins,flavonoids,and unsaturated fatty acids.We discuss the potential of multi-gene stacking,gene editing,enzyme engineering,and artificial intelligence in synthetic metabolic engineering.We propose future research directions and potential solutions centered on leveraging AI-driven systems biology,precision gene editing,enzyme engineering,agrobacterium-mediated genotype-independent transformation,and modular metabolic engineering strategies to develop next-generation nutritionally enhanced super crops and transform global food systems. 展开更多
关键词 Synthetic biology Synthetic metabolism engineering functional crops Multigene stacking and gene editing Artificial intelligence
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Linking starch particle physicochemical properties to functionality in medicinal plants:Insights from Polygonum multiflorum and Smilax glabra 被引量:1
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作者 Nan Wang Lingling Wu +2 位作者 Yaya Su Haifeng Tang Hailong Yuan 《Chinese Chemical Letters》 2026年第1期487-491,共5页
This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared ... This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared spectroscopy,X-ray diffraction,high-performance anion-exchange chromatography,and differential scanning calorimetry.Significant differences were observed in their morphological,physicochemical,and functional properties.PMS had a smaller particle size(13.68 μm),irregular polygonal shape,A-type,lower water absorption(62.67 %),and higher oil absorption(51.17 %).In contrast,SGS exhibited larger particles(31.75 μm),a nearly spherical shape,B-type,higher crystallinity(50.66 %),and greater amylose content(21.54 %),with superior thermal stability,shear resistance,and gelatinization enthalpy.SGS also contained higher resistant starch(83.28 %) and longer average chain length(20.58 %),but showed lower solubility,swelling power,light transmittance,and freeze-thaw stability.The physicochemical properties differences in crystal pattern and particle morphology between PMS and SGS lead to distinct behaviors during in vitro digestion and fermentation.These findings highlight the potential of medicinal plant starches in functional ingredients and industrial processes. 展开更多
关键词 Starch particle Physicochemical properties Starch function Resistant starch Starch extraction
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The Analysis of Gauss Radial Basis Functions and Its Application in Locating Olivine on the Moon
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作者 SONG Shicang SONG Xiaoyuan SONG Shuhan 《应用数学》 北大核心 2026年第1期173-181,共9页
Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the m... Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the main contributions is proving this property using linear algebra instead of profound knowledge.This makes it easy to read and understand this fundamental fact.The proof of linear independence of a set of Gauss functions relies on the constructing method for one-dimensional space and on the deducing method for higher dimensions.Additionally,under the condition of preserving the same moments between the original function and interpolating function,both the interpolating existence and uniqueness are proven for GRBF in one-dimensional space.The final work demonstrates the application of the GRBF method to locate lunar olivine.By combining preprocessed data using GRBF with the removing envelope curve method,a program is created to find the position of lunar olivine based on spectrum data,and the numerical experiment shows that it is an effective scheme. 展开更多
关键词 Gauss function Radial basis function Machine learning Lunar olivine locating Data fitting
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Differing functions of two CYP716 genes for saikosaponin biosynthesis in Bupleurum chinense 被引量:1
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作者 Kaimi Dong Hua Chen +14 位作者 Ma Yu Shiying Wang Xue Yin Chuanxin Mo Meng Zhang Yuchan Li Yong Luo Zeru Yu Zisong Yang Jun Zhao Chao Xin Wenshuai Chen Zhen Ni Zheyong Xue Jianhe Wei 《The Crop Journal》 2026年第1期224-234,共11页
Saikosaponins are the major pharmacologically active components in Bupleurum genus and exhibit significant application potential in multiple fields such as immune regulation and anti-tumor activity.To elucidate the bi... Saikosaponins are the major pharmacologically active components in Bupleurum genus and exhibit significant application potential in multiple fields such as immune regulation and anti-tumor activity.To elucidate the biosynthetic pathway of saikosaponins,we identified two cytochrome P450 monooxygenases,CYP716A41 and CYP716Y4,in Bupleurum chinense.These enzymes catalyze the C-28 oxidation and C-16 hydroxylation of oleanane-type triterpene skeletons,respectively.The catalytic efficiency of CYP716A41 from a southern B.chinense variety was significantly higher than that from a northern variety.Molecular docking and mutagenesis experiments revealed that amino acid residues at sites 9 and 35 may contribute to this difference in catalytic efficiency.Additionally,under cold stress,the expression levels of both CYP450 genes and the saikosaponin contents in the leaves of southern varieties were significantly higher compared to those in northern varieties.The variation in the catalytic efficiency of CYP716A41 and the differential expression of the two CYP450 genes under cold stress during winter are associated with the differences in saikosaponin biosynthesis in the leaves of southern and northern B.chinense varieties.This is consistent with the distinct medicinal usage practices observed between southern and northern China. 展开更多
关键词 Bupleurum chinense Medicinal tissue utilization Saikosaponin biosynthesis pathway CYP716 functional verification
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Microglia overexpressing brain-derived neurotrophic factor promote vascular repair and functional recovery in mice after spinal cord injury 被引量:2
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作者 Fanzhuo Zeng Yuxin Li +6 位作者 Xiaoyu Li Xinyang Gu Yue Cao Shuai Cheng He Tian Rongcheng Mei Xifan Mei 《Neural Regeneration Research》 2026年第1期365-376,共12页
Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in s... Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in spinal cord injury.Previous studies have shown that microglia can promote neuronal survival by phagocytosing dead cells and debris and by releasing neuroprotective and anti-inflammatory factors.However,excessive activation of microglia can lead to persistent inflammation and contribute to the formation of glial scars,which hinder axonal regeneration.Despite this,the precise role and mechanisms of microglia during the acute phase of spinal cord injury remain controversial and poorly understood.To elucidate the role of microglia in spinal cord injury,we employed the colony-stimulating factor 1 receptor inhibitor PLX5622 to deplete microglia.We observed that sustained depletion of microglia resulted in an expansion of the lesion area,downregulation of brain-derived neurotrophic factor,and impaired functional recovery after spinal cord injury.Next,we generated a transgenic mouse line with conditional overexpression of brain-derived neurotrophic factor specifically in microglia.We found that brain-derived neurotrophic factor overexpression in microglia increased angiogenesis and blood flow following spinal cord injury and facilitated the recovery of hindlimb motor function.Additionally,brain-derived neurotrophic factor overexpression in microglia reduced inflammation and neuronal apoptosis during the acute phase of spinal cord injury.Furthermore,through using specific transgenic mouse lines,TMEM119,and the colony-stimulating factor 1 receptor inhibitor PLX73086,we demonstrated that the neuroprotective effects were predominantly due to brain-derived neurotrophic factor overexpression in microglia rather than macrophages.In conclusion,our findings suggest the critical role of microglia in the formation of protective glial scars.Depleting microglia is detrimental to recovery of spinal cord injury,whereas targeting brain-derived neurotrophic factor overexpression in microglia represents a promising and novel therapeutic strategy to enhance motor function recovery in patients with spinal cord injury. 展开更多
关键词 ANGIOGENESIS apoptosis brain-derived neurotrophic factor colony stimulating factor 1 receptor inflammation MICROGLIA motor function spinal cord injury vascular endothelial growth factor
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Nickel-Catalyzed Borylation of Aryl Nonaflates for the Efficient Synthesis of Arylboronates via C—O Bond Functionalization
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作者 Liang Yuan Gui Chao +3 位作者 Wang Wenwen Chu Xueqiang Xu Hao Shen Zhiliang 《有机化学》 北大核心 2026年第1期207-214,共8页
Nickel-catalyzed borylation of aryl nonaflates with B2pin2 could be realized,which proceeded effectively by means of C—O bond functionalization to afford a wide variety of valuable arylboronates in moderate to excell... Nickel-catalyzed borylation of aryl nonaflates with B2pin2 could be realized,which proceeded effectively by means of C—O bond functionalization to afford a wide variety of valuable arylboronates in moderate to excellent yields with good functionality compatibility.In addition,the gram-scale synthesis and the application of the approach in the late-stage elaboration of aryl nonaflate derived from pterostilbene could also be achieved. 展开更多
关键词 nickel catalysis BORYLATION aryl nonaflates arylboronates C-O bond functionalization
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The Asymptotic Distribution of General Divisor Problem Associated to Dedekind Zeta Function over Certain Sequences
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作者 HUA Guodong 《数学进展》 北大核心 2026年第2期292-314,共23页
Let K_(j)/Q,1≤j≤ν,ν≥2 be quadratic fields with pairwise coprime discriminants Dj,and let τ_(kj)^(K_(j))(n)be the divisor function associated to Dedekind zeta function SK_(j)(s).In this paper,we consider a multid... Let K_(j)/Q,1≤j≤ν,ν≥2 be quadratic fields with pairwise coprime discriminants Dj,and let τ_(kj)^(K_(j))(n)be the divisor function associated to Dedekind zeta function SK_(j)(s).In this paper,we consider a multidimensional general divisor problem related to the τ_(kj)^(K_(j))(n)involving several number fields over square integers,by establishing the corresponding asymptotic formula.As an application,we also obtain the asymptotic formula of variance of these coefi icients. 展开更多
关键词 non-normal cubic field Dekekind zeta function divisor problem
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IMPROVEMENT ON HANKEL DETERMINANT BOUNDS FOR SPECIFIC HOLOMORPHIC FUNCTIONS
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作者 Huo TANG Muhammad ABBAS +1 位作者 Reem K.ALHEFTHI Muhammad ARIF 《Acta Mathematica Scientia》 2026年第1期39-61,共23页
In recent years,researchers have extensively investigated the Hankel determinant,which consists of coefficients appearing in a holomorphic function’s Taylor-Maclaurin series.Hankel matrices are widely used in Markov ... In recent years,researchers have extensively investigated the Hankel determinant,which consists of coefficients appearing in a holomorphic function’s Taylor-Maclaurin series.Hankel matrices are widely used in Markov processes,non-stationary signals,and other mathematical disciplines.The aim of the current research article is to first improve the bounds of coefficient-related problems by employing the well-known Carathéodory function.The problems that we are going to improve were obtained by Tang et al.The sharp estimates of the most difficult problem of geometric function theory known as the third-order Hankel determinant are also contributed here.Zalcman and Fekete-Szegöinequalities are also studied here for the defined family of holomorphic functions. 展开更多
关键词 holomorphic function Carathéodory function Hankel determinant Zalcman inequality
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The characteristics of cerebral cortical oxygenation levels and functional connectivity under upper and lower limb exercise-induced fatigue
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作者 Feng Li Yajie Wang +3 位作者 Xinyi Wang Jiawei Bi Ye Luo Lingyan Huang 《Sports Medicine and Health Science》 2026年第1期61-69,共9页
This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fati... This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fatigue was induced using an upper limb ergometer or a lower limb ergometer,with the load increasing gradually each minute.fNIRS covering the prefrontal cortex and motor cortex were used to collect data during the resting state,both before and after fatigue induction.A two-way ANOVA was conducted to examine differences in oxyhemoglobin(HbO_(2))and functional connectivity before and after fatigue induction in both groups,with the significance level set at 0.05.Exercise-induced fatigue in both the upper and lower limbs leads to a significant decrease in cerebral cortical oxygenation levels.Upper limb fatigue leads to a significant reduction in functional connectivity,there were significant decreases in connectivity within the motor cortex,between the motor cortex and frontal regions,and between the right ventrolateral prefrontal cortex and other frontal regions.Conversely,no significant changes were observed before and after lower limb fatigue.Future studies should focus on examining the extent to which how changes in the cerebral cortex,induced by exercise fatigue,are linked to exercise-and/or performance-related outcomes. 展开更多
关键词 Brain functional connectivity Cerebral oxygenation level Exercise-induced fatigue functional near-infrared spectroscopy
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Intelligent Environmental Sensing Systems:Integrating IoT,Edge Computing,and Real-Time Analytics for Environmental Monitoring
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作者 Huanle Zhang Xuebin Wang 《Journal of Environmental & Earth Sciences》 2026年第3期169-197,共29页
The intelligent environmental sensing systems are quickly transforming the sparse and retrospective monitoring to dense and decision-oriented environmental intelligence.This review brings together the manner in which ... The intelligent environmental sensing systems are quickly transforming the sparse and retrospective monitoring to dense and decision-oriented environmental intelligence.This review brings together the manner in which integration of Internet of Things(IoT)sensing,edge computing,and real-time analytics facilitates timely detection,interpretation,and prediction of the environmental conditions across the applications,such as urban air quality,watershed and coastal surveillance,industrial safety,agriculture,and disaster response.We define end-to-end architectural patterns to organize devices,edge nodes,and cloud services to satisfy latency,reliability,bandwidth,and governance constraints with emphasis on event-time processing,adaptive offloading,and hierarchical aggregation.Then we look at sensing and infrastructure foundations,emphasizing the effects of sensor modality and power autonomy,connectivity,and the practices of calibration on the practicable analytics and eventual plausibility.It is on this basis that we examine real-time analytics pipelines and Artificial Intelligence(AI)techniques to preprocess,sensor combine,anomaly detect,and short-horizon forecast,with a focus on edge-deployable models,quantification of uncertainties,and query resistance to drift and domain shift.Lastly,we address the realities of deployment that condition operational success,such as lifecycle engineering,provenance-aware data management,security and privacy risks,ethical governance,and evaluation methodologies,which place end-to-end latency and field generalization as a priority.This review offers cohesion to algorithmic capabilities and systems engineering and governance to define an overall framework,show open areas of research directions,and provide practical recommendations on how to design trustworthy,scalable,and sustainable environmental monitoring systems. 展开更多
关键词 Internet of Things Edge Computing Real-Time analytics Sensor Fusion Environmental Monitoring
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Artificial intelligence in functional gastrointestinal disorders:From precision diagnosis to preventive healthcare
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作者 Yi-Nan Yan Jing-Qi Zeng Xia Ding 《Artificial Intelligence in Gastroenterology》 2026年第1期20-35,共16页
Functional gastrointestinal disorders(FGIDs),including irritable bowel syndrome(IBS),functional dyspepsia(FD),and gastroesophageal reflux disease(GERD),present persistent diagnostic and therapeutic challenges due to s... Functional gastrointestinal disorders(FGIDs),including irritable bowel syndrome(IBS),functional dyspepsia(FD),and gastroesophageal reflux disease(GERD),present persistent diagnostic and therapeutic challenges due to symptom heterogeneity and the absence of reliable biomarkers.Artificial intelligence(AI)enables the integration of multimodal data to enhance FGID management through precision diagnostics and preventive healthcare.This minireview summarizes recent advancements in AI applications for FGIDs,highlighting progress in diagnostic accuracy,subtype classification,personalized interventions,and preventive strategies inspired by the traditional Chinese medicine concept of“treating the undiseased”.Machine learning and deep learning algorithms have demonstrated value in improving IBS diagnosis,refining FD neuro-gastrointestinal subtyping,and screening for GERD-related complications.Moreover,AI supports dietary,psychological,and integrative medicine-based interventions to improve patient adherence and quality of life.Nonetheless,key challenges remain,including data heterogeneity,limited model interpretability,and the need for robust clinical validation.Future directions emphasize interdisciplinary collaboration,the development of multimodal and explainable AI models,and the creation of patientcentered platforms to facilitate a shift from reactive treatment to proactive prevention.This review provides a systematic framework to guide the clinical application and theoretical innovation of AI in FGIDs. 展开更多
关键词 Artificial intelligence functional gastrointestinal disorders Irritable bowel syndrome functional dyspepsia Gastroesophageal reflux disease
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On Analytical Modeling for Fast Multi-Objective Torque Allocation in Over-Actuated IWM Vehicles
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作者 Fadel Tarhini Reine Talj Moustapha Doumiati 《IEEE/CAA Journal of Automatica Sinica》 2026年第2期346-365,共20页
Efficient torque allocation in over-actuated vehicles poses a central challenge in the domain of advanced vehicle control.These vehicles,featuring redundant actuators,provide an exceptional avenue for enhancing perfor... Efficient torque allocation in over-actuated vehicles poses a central challenge in the domain of advanced vehicle control.These vehicles,featuring redundant actuators,provide an exceptional avenue for enhancing performance,stability,and efficiency.This paper presents a pioneering tendency for torque allocation in the context of over-actuated vehicles,particularly inwheel motor(IWM)driven electric vehicles.We introduce a systematic methodology grounded in analytical modeling,allowing for the efficient reconciliation of multiple,often conflicting objectives.The explicit functions are analytically modeled to enhance stability and energy economy.Additionally,a fuzzy logic-based torque allocation strategy is developed and compared,along with other literature methods,with the analytical models.Simulations are conducted in a joint simulation between Simulink/MATLAB and SCANeR Studio vehicle dynamics simulator,followed by validation on a real-world dataset.Our findings elucidate the proficiency of the analytical models on vehicle performance,stability,computational efficiency,and energy consumption. 展开更多
关键词 analytical modeling energy economy fuzzy logic over-actuated vehicles stability torque allocation
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Effectiveness of conventional municipal wastewater treatment plants in microplastics removal:Insights from multiple analytical techniques
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作者 Simone Cavazzoli Costanza Scopetani +9 位作者 David Chelazzi Tania Martellini Alessandra Cincinelli Emiliano Carretti Miriam Ascolese Riccardo Gori Karl Mair Werner Tirler Massimo Donegà Gianni Andreottola 《Journal of Environmental Sciences》 2026年第2期424-438,共15页
This study investigated microplastics(MPs)sized 10–5000μm across stages of a conventional municipal wastewater treatment plant using multiple analytical techniques.Samples were collected via pumping and filtration,t... This study investigated microplastics(MPs)sized 10–5000μm across stages of a conventional municipal wastewater treatment plant using multiple analytical techniques.Samples were collected via pumping and filtration,treated with the Fenton reaction for wet peroxidation,and separated by density separation.Analysis employed Focal Plane Array Micro-Fourier Transform Infrared Spectroscopy(FPA micro-FTIR),a widely used technique in MPs analysis,alongside the less common Laser Direct Infrared Spectroscopy(LDIR),providing complementary data on particle composition,shape,size,and colour.To enhance insights,spectroscopic methods were supplemented with Thermal Desorption Gas Chromatography-Mass Spectrometry(TD-GC/MS),calibrated for specific polymers,to quantify MPs by mass and assess removal efficiency.Wastewater treatment effectively reduced MPs.In influent samples,concentrations reached 72 MPs/L(FTIR),2117 MPs/L(LDIR),and 177μg/L(TD-GC/MS).Primary treatments removed 41%–55%,while the wastewater treatment plant effluent contained 1 MPs/L(FTIR),93 MPs/L(LDIR),and 2μg/L(TD-GC/MS),reflecting 96%–99%removal efficiency.Activated sludge showed concentrations of 123 MPs/L(FTIR),10,800 MPs/L(LDIR),and 0.3 mg/g dry weight(TD-GC/MS),underscoring its role in MPs capture.However,sludge dewatering released significant MPs into centrifuge rejected water:484 MPs/L(FTIR),23,000 MPs/L(LDIR),and 1100μg/L(TD-GC/MS).These results highlight the effectiveness of conventional treatments in MPs removal and the critical role of sludge in capturing these contaminants.However,sludge dewatering poses a risk of reintroducing MPs into the environment.Effective sludge management should prioritize nutrient recovery and biomass valorisation to mitigate these risks and minimise harmful environmental impacts. 展开更多
关键词 Emerging contaminant Plastic pollution analytical method Spectroscopy SPECTROMETRY MPs in WWTPs
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A Benchmark Study of Density Functional Theory(DFT)Methods for Mo-Catalyzed Carbonyl Oxidative Addition
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作者 Chen Zitong Wang Liwei +1 位作者 Shen Xiao Qi Xiaotian 《有机化学》 北大核心 2026年第2期507-514,共8页
In molybdenum chemistry,the oxidative addition of o-quinone or 1,2-dicarbonyl compounds to molybdenum has been widely used in Mo-catalyzed C—C bond construction.The carbonyl oxidative addition to Mo(0)or Mo(Ⅱ)is the... In molybdenum chemistry,the oxidative addition of o-quinone or 1,2-dicarbonyl compounds to molybdenum has been widely used in Mo-catalyzed C—C bond construction.The carbonyl oxidative addition to Mo(0)or Mo(Ⅱ)is the critical elementary reaction of molybdenum catalysis.However,the relevant density functional theory(DFT)studies are relatively scarce,especially regarding the rational selection of functionals.In this work,14 functionals were employed to investigate the Mo-catalyzed carbonyl oxidative addition step.A benchmark study was carried out to evaluate their performance in structure optimization and energy calculation.Analyses of mean absolute error(MAE)and mean squared error(MSE)indicated that the B3LYP-D3(BJ),TPSSh,and ωB97X-D functionals exhibited superior performance in structure optimization.Using the DLPNO-CCSD(T)functional as the reference,the M06,M06-L,and MN15-L functionals exhibited good performance for energy calculation based on the structures optimized using the B3LYP-D3(BJ)functional.In particular,MN15-L provided the best performance with the smallest MAE and MSE. 展开更多
关键词 molybdenum catalysis carbonyl oxidation addition density functional theory(DFT)calculation DFT benchmark study
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Functional genes associated with the occurrence of mycotoxins produced by Aspergillus in foods
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作者 Mei Gu Can Liu +4 位作者 Xiaofeng Yue Du Wang Xiaoqian Tang Qi Zhang Peiwu Li 《Journal of Integrative Agriculture》 2026年第2期585-601,共17页
Aspergillus species are ubiquitous fungi that produce mycotoxins(secondary metabolites)known as sterigmatocystin and aflatoxins in many different kinds of foods,which leads to serious contamination in agricultural pro... Aspergillus species are ubiquitous fungi that produce mycotoxins(secondary metabolites)known as sterigmatocystin and aflatoxins in many different kinds of foods,which leads to serious contamination in agricultural products,thereby endangering human health.Extensive studies on Aspergillus fungi have been conducted on growth and development,aflatoxin biosynthesis,and their interactions with environment.Here,we summarized a series of functional genes of the main Aspergillus fungi relative to toxins occurrence in foods,which revealed the signal transduction mechanisms of their involvement in growth and development,toxin production,and response to light,anticipating providing theoretical guidance on developing control and prevention technologies for mycotoxin contamination in agricultural products to ensure food safety. 展开更多
关键词 functional genes ASPERGILLUS AFLATOXIN DEVELOPMENT
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Periodontitis pathogen Porphyromonas gingivalis promotes chronic obstructive pulmonary disease via affecting neutrophils chemotaxis and function
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作者 Luyao Zhang Huan Tian +4 位作者 Yuanyuan Ma Jing Xu Chang Guo Zuomin Wang Jie Ma 《International Journal of Oral Science》 2026年第1期115-125,共11页
Chronic obstructive pulmonary disease(COPD),a disease responsible for early mortality worldwide,is well accepted to be associated with periodontitis epidemiologically.Although both of the diseases are the multi-microb... Chronic obstructive pulmonary disease(COPD),a disease responsible for early mortality worldwide,is well accepted to be associated with periodontitis epidemiologically.Although both of the diseases are the multi-microbial inflammatory disease,the precise underlying mechanisms by which periodontitis influences the progression of COPD remains largely unknown.Here,we established COPD accompanied with periodontitis mouse models and observed the pronounced progress in pulmonary symptoms and histopathology,cha racterized by poorer respiratory function,thicke ned bronchial walls,and increased neutrophils infiltration in lung tissue.Mechanistically,periodontitis pathogen Porphyromonas gingivalis(P.gingivalis)relocated in the lung through the respiratory tract and LPS from P.gingivalis promoted the secretion of chemokines CXCL2 and G-CSF of alveolar epithelial cells through NF-κB and p38 MAPK pathways to recruit neutrophils.Furthermore,exposure to P.gingivalis of infiltrated neutrophils released matrix metallopeptidase-8(MMP-8)and neutrophil elastase(NE),which aggravated airway inflammation and tissue damage.These findings indicated that periodontitis could exacerbate COPD via its pathogen P.gingivalis,which translocated in the lung and stimulated neutrophil chemotaxis and activation in the lung. 展开更多
关键词 neutrophils chemotaxis pulmonary symptoms HISTOPATHOLOGY PERIODONTITIS neutrophils function chronic obstructive pulmonary disease respiratory function chronic obstructive pulmonary disease copd
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Analytical solution for longitudinal responses of tunnels under combined effects of seismic waves and strike-slip faulting
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作者 Jie Tang Manchao He +2 位作者 Yafei Qiao Hanbing Bian Chun Zhu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1266-1289,共24页
Strong seismic excitation and fault dislocation are likely to occur simultaneously in high-intensity seismic zones,causing severe damage to tunnels crossing active fault zones.This paper aims to develop a novel analyt... Strong seismic excitation and fault dislocation are likely to occur simultaneously in high-intensity seismic zones,causing severe damage to tunnels crossing active fault zones.This paper aims to develop a novel analytical solution to determine the longitudinal mechanical responses of tunnels subjected to the combined effects of seismic waves and strike-slip faulting.Adopting the elastic springbeam model,the seismic waves are modelled as shear horizontal(SH)waves and the fault dislocation follows an S-shaped pattern;the superposition principle for free-fielddisplacements caused by both effects is assumed.In addition,the transmission and reflectionof seismic waves at the fault-rock geological interface and the tangential contact conditions at the tunnel-rock interface are considered.The analytical model is validated against numerical simulations,confirmingits accuracy in calculating tunnel responses.Moreover,a parametric study is conducted to evaluate the impact of key factors,including fault displacement,fault zone width,fault dip angle,earthquake frequency,rock conditions,tunnel lining stiffness,and tangential contact conditions,on tunnel responses.Compared with each effect alone,the combined effects of seismic waves and strike-slip faulting significantlychange the tunnel deformation and internal forces,leading to increased tunnel responses,especially within the fault zone and near the fault-rock interfaces.Depending on specificparameters,tunnel responses can be classifiedinto seismic-dominated,faulting-dominated,and seismic-faulting coupled responses on the basis of the relative contributions of each effect.The proposed analytical solution can be applied to quickly predict the longitudinal mechanical behaviour of tunnels under such combined effects in engineering applications. 展开更多
关键词 Strike-slip faulting Longitudinal tunnel response analytical solution Seismic waves Wave transmissions and reflections
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