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Parental autonomy support effects on children’s school adjustment:The longitudinal mediating effect of executive function
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作者 Xia Hu Zhu Li +1 位作者 Yawen Shi Xiaopei Xing 《Journal of Psychology in Africa》 2025年第4期471-480,共10页
This longitudinal study examined the association between parental autonomy support and school-aged children’s adjustment across four major domains of school functioning,as well as the mediating role of children’s ex... This longitudinal study examined the association between parental autonomy support and school-aged children’s adjustment across four major domains of school functioning,as well as the mediating role of children’s executive function.Participants were 476 school-aged children(girl:49.2%,M_(age)=10.49 years,SD=1.32 years),who completed the Psychological Autonomy Support Scale,the Behavior Rating Inventory of Executive Function–2,and the Primary School Students’Psychological Suzhi Scale at baseline and at two subsequent follow-up assessments.Results from unconditional latent growth curve models and structural equation modeling indicated that paternal autonomy support was a significant predictor of children’s adjustment across all four school domains.In contrast,maternal autonomy support was significantly associated only with interpersonal adjustment.Both the intercept(initial level)and slope(rate of change)of children’s executive function significantly predicted their adjustment in all four domains.Notably,the initial level of executive function fully mediated the association between paternal autonomy support and school adjustment,whereas the rate of change in executive function did not serve as a significant mediator.Thesefindings underscore the importance of promoting parental autonomy-supportive behaviors-particularly among fathers-as a means to enhance children’s executive functioning and,consequently,their school adjustment. 展开更多
关键词 parental autonomy support executive function school adjustment longitudinal mediation
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Nutritional and social support enhance cognitive function in acute cerebral infarction patients
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作者 Jin Gong Jie Zheng 《World Journal of Psychiatry》 2025年第10期203-212,共10页
BACKGROUND Acute ischemic stroke(AIS)is a leading global cause of disability and mortality,with post-stroke cognitive impairment(PSCI)affecting 20%-40%of survivors.PSCI ranges from mild cognitive decline to dementia,s... BACKGROUND Acute ischemic stroke(AIS)is a leading global cause of disability and mortality,with post-stroke cognitive impairment(PSCI)affecting 20%-40%of survivors.PSCI ranges from mild cognitive decline to dementia,severely hindering functional recovery,increasing healthcare costs,and elevating risks of recurrent stroke and death.While nutritional support aids neuronal repair and reduces oxidative damage,and social support alleviates psychological distress,existing studies often evaluate these interventions in isolation.This study investigates the combined effects of standardized nutritional intervention and structured social support on cognitive function,psychological status,and quality of life(QoL)in AIS patients with cognitive dysfunction,aiming to establish an integrated rehabilitation model.AIM To explore the effects of nutritional intervention and social support on the cognitive function and psychological status in patients with acute cerebral infarction complicated by cognitive dysfunction.METHODS A retrospective study was conducted.A total of 59 patients with acute cerebral infarction complicated by cognitive dysfunction from January 2023 to December 2023 were selected as the control group.Another 59 patients with the same condition were selected as the research group.The research group received standardized nutritional intervention and regular social support,including dietary guidance,nutritional supplementation,psychological counseling,and family support plans.The control group received routine medical care.Cognitive function,anxiety,depression,QoL,sleep quality,nutritional status,and family satisfaction were compared between the two groups.RESULTS The Montreal Cognitive Assessment(MoCA)and Mini-Mental State Examination differences(P<0.05).Pearson correlation analysis showed that increases in serum albumin(Alb),prealbumin(PAB),and hemoglobin(Hb)were all highly and significantly associated with improvements in MMSE and MoCA scores(P<0.05).The Self-Rating Anxiety Scale and Self-Rating Depression Scale scores of the research group were lower than those of the control group,with statistically significant differences(P<0.05).The scores of QoL dimensions in the research group were higher than those of the control group,with statistically significant differences(P<0.05).The Pittsburgh Sleep Quality Index scores and total score of the research group were lower than those of the control group,with statistically significant differences(P<0.05).The serum Alb,PAB,and Hb levels in the research group were higher than those of the control group,with statistically significant differences(P<0.05).The Social Disability Screening Schedule scores of the research group were lower than those of the control group,with statistically significant differences(P<0.05).The family satisfaction of the research group was significantly higher than that of the control group,with statistically significant differences(P<0.05).CONCLUSION Nutritional intervention and social support significantly improved the cognitive function,psychological status,and QoL in patients with acute cerebral infarction complicated by cognitive dysfunction.These interventions reduced anxiety and depression symptoms,improved sleep and nutritional status,and enhanced the social adaptability of patients as well as family satisfaction. 展开更多
关键词 Nutritional intervention Social support Acute cerebral infarction Cognitive dysfunction
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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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Dysfunctional attitudes,social support,and adolescent depression
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作者 Xi Yang Peng Li +1 位作者 Gui-Ying Liu Dan Shan 《World Journal of Psychiatry》 2025年第4期337-344,共8页
Adolescent depressive symptoms represent a significant public health concern,with negative life events and dysfunctional attitudes playing pivotal roles in theirdevelopment.A cross-sectional study by Yu et al assessed... Adolescent depressive symptoms represent a significant public health concern,with negative life events and dysfunctional attitudes playing pivotal roles in theirdevelopment.A cross-sectional study by Yu et al assessed the interplay betweendysfunctional attitudes,social support,and depressive symptoms in 795 Chineseadolescents(49.9%male,mean age 15.2±1.8 years,age range 11-18 years)fromfive middle schools in Shandong Province.Using the Dysfunctional AttitudesScale,Adolescent Life Events Scale,Beck Depression Inventory,and SocialSupport Rating Scale,the study identified that dysfunctional attitudes,particularlyover-autonomy and over-perfectionism,mediate the relationship betweennegative life events and depressive symptoms.Social support moderated thisrelationship,significantly reducing depressive symptoms.These findingsunderscore the need for preventive and therapeutic strategies targeting dysfunctionalattitudes and enhancing social support to address adolescent depressivesymptoms.In this article,we extend their findings to highlight the significance ofculturally tailored interventions that incorporate familial and communitydynamics in mitigating depressive symptoms,particularly in collectivist societies. 展开更多
关键词 Adolescent depression Dysfunctional attitudes Social support Negative life events Over-autonomy Over-perfectionism
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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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Using mixed kernel support vector machine to improve the predictive accuracy of genome selection
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作者 Jinbu Wang Wencheng Zong +6 位作者 Liangyu Shi Mianyan Li Jia Li Deming Ren Fuping Zhao Lixian Wang Ligang Wang 《Journal of Integrative Agriculture》 2026年第2期775-787,共13页
The advantages of genome selection(GS) in animal and plant breeding are self-evident.Traditional parametric models have disadvantage in better fit the increasingly large sequencing data and capture complex effects acc... The advantages of genome selection(GS) in animal and plant breeding are self-evident.Traditional parametric models have disadvantage in better fit the increasingly large sequencing data and capture complex effects accurately.Machine learning models have demonstrated remarkable potential in addressing these challenges.In this study,we introduced the concept of mixed kernel functions to explore the performance of support vector machine regression(SVR) in GS.Six single kernel functions(SVR_L,SVR_C,SVR_G,SVR_P,SVR_S,SVR_L) and four mixed kernel functions(SVR_GS,SVR_GP,SVR_LS,SVR_LP) were used to predict genome breeding values.The prediction accuracy,mean squared error(MSE) and mean absolute error(MAE) were used as evaluation indicators to compare with two traditional parametric models(GBLUP,BayesB) and two popular machine learning models(RF,KcRR).The results indicate that in most cases,the performance of the mixed kernel function model significantly outperforms that of GBLUP,BayesB and single kernel function.For instance,for T1 in the pig dataset,the predictive accuracy of SVR_GS is improved by 10% compared to GBLUP,and by approximately 4.4 and 18.6% compared to SVR_G and SVR_S respectively.For E1 in the wheat dataset,SVR_GS achieves 13.3% higher prediction accuracy than GBLUP.Among single kernel functions,the Laplacian and Gaussian kernel functions yield similar results,with the Gaussian kernel function performing better.The mixed kernel function notably reduces the MSE and MAE when compared to all single kernel functions.Furthermore,regarding runtime,SVR_GS and SVR_GP mixed kernel functions run approximately three times faster than GBLUP in the pig dataset,with only a slight increase in runtime compared to the single kernel function model.In summary,the mixed kernel function model of SVR demonstrates speed and accuracy competitiveness,and the model such as SVR_GS has important application potential for GS. 展开更多
关键词 genome selection machine learning support vector machine kernel function mixed kernel function
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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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Association between liver function at hospital admission and mortality in pediatric patients receiving postcardiotomy venoarterial extracorporeal membrane oxygenation support
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作者 Jia Liu Yu Jin +5 位作者 Wang He Wenting Wang Peng Gao Peiyao Zhang Bingyang Ji Jinping Liu 《World Journal of Emergency Medicine》 2025年第6期579-585,共7页
BACKGROUND:Preoperative liver function in children with congenital heart disease is often compromised to varying degrees because of the unique pathophysiology.We aimed to investigate the relationships between liver fu... BACKGROUND:Preoperative liver function in children with congenital heart disease is often compromised to varying degrees because of the unique pathophysiology.We aimed to investigate the relationships between liver function indicators at hospital admission and mortality in children receiving venoarterial extracorporeal membrane oxygenation(VA-ECMO)support following cardiac surgery.METHODS:We retrospectively analysed the clinical data of pediatric patients who received postcardiotomy VA-ECMO support at Fuwai Hospital between January 2010 and June 2020.Univariable and multivariable-adjusted Cox proportional hazard models were constructed to evaluate the risk factors associated with 30-day and 180-day mortality.The cut-off values for the liver function variables measured at hospital admission were categorized into high and low groups and then compared using Kaplan-Meier survival curves and log-rank tests.RESULTS:Our study included 96 pediatric patients who received VA-ECMO support after cardiotomy.Among the patients receiving VA-ECMO,the 30-day and 180-day mortality rates were 37.5% and 52.1%,respectively.The level of aspartate aminotransferase(AST)at admission was associated with 30-day mortality(hazard ratios[HRs]=1.852,95%CI 1.010-3.398,P=0.046).The AST and alkaline phosphatase(ALP)levels were predictors of 180-day mortality,with adjusted HRs of 1.799(95%CI 1.074-3.014;P=0.025)and 1.384(95%CI 1.050-1.825;P=0.021),respectively.The cut-off value for AST to predict mortality at 30 d was 77 U/L,and that for ALP to predict mortality at 180 d was 269 U/L.CONCLUSION:Liver function indicators,including AST and ALP,at hospital admission are associated with mortality risk in children with congenital heart disease receiving VA-ECMO after cardiac surgery. 展开更多
关键词 Liver function Congenital heart disease Veno-arterial extracorporeal membrane oxygenation PEDIATRIC Postcardiotomy
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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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Characterization of rock damage evolution and support timing under true triaxial unloading paths
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作者 QI Min-jie ZHAO Guang-ming +6 位作者 MENG Xiang-rui LIU Chong-yan XU Wen-song XU Xin ZHAO Cong-hui SUN Kai ZHAO Bin 《Journal of Central South University》 2026年第1期442-465,共24页
To study the influence of support timing and support strength on the mechanical properties and deformation damage characteristics of a single-sided unloaded rock mass,a true triaxial perturbation unloaded rock testing... To study the influence of support timing and support strength on the mechanical properties and deformation damage characteristics of a single-sided unloaded rock mass,a true triaxial perturbation unloaded rock testing system was used to conduct rock damage tests on sandstone with different support timing and strength paths.Based on the acoustic emission monitoring system,the spatial and temporal evolution characteristics of the whole process of rock body loaded instability under two stress paths were studied,and the mechanism of the reinforcing effect of stress support on the unloaded rock mass was analyzed.The results show that,within the scope of this study,both earlier applications of shoring and an increase in shoring strength can effectively improve the ultimate bearing capacity of the unloaded rock,which increases the ultimate bearing capacity of the unloaded rock mass by 60.31% and 54.96%,respectively;There is a phenomenon of rebound deformation of the rock mass during sudden changes in stress(single-sided unloading,stress support),which shows opposite expansion and compression platforms on the stress−strain curve;The crack evolution of unloaded rock under different stress support conditions shows the state law of"initial crack activation→middle steady state expansion→late main crack penetration",and the lagging support significantly accelerates the crack evolution from local activation to main penetration;The single-sided unloading and stress-supporting stages have less influence on the unloading deformationsσ_(1u),σ_(2u) and support deformationsσ_(1) t,σ_(2t) in theσ_(1) andσ_(2)directions,while they show significant response characteristics toσ_(3u),σ_(vu) and σ_(3) t,σ_(vt),and with the increase of the support strength,the stress-supporting stagesσ_(3) t,σ_(vt) gradually increase and exceed the deformations generated by the unloading stagesσ_(3u),σ_(vu);The increase of support strength can effectively compensate for the rock stress loss caused by unloading,which makes the maximum,minimum,and volumetric strain support coefficients during the loading and unloading of the rock body increase gradually while the effect on the intermediate principal strain support coefficient is small;During loading,the support strength of rock masses seeks a new bearing area by regulating stress equilibrium states.This process primarily manifests as a shift in the locations of the crushing zone and the main bearing area,accompanied by a corresponding transformation in failure patterns.Consequently,the rock mass transitions from asymmetric three-zone damage under no or weak support to approximate symmetric three-zone damage under strong support.Simultaneously,the main load-bearing area of the rock mass shifts from deep bearing in the unsupported to middle bearing under strong support as the support strength increases. 展开更多
关键词 true triaxial single-sided unloading unloading effect support timing support strength
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Immobilization strategies,supporting materials,and performance advantages of photocatalysts in ammonia synthesis
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作者 Qian Su Pengfei Wang +1 位作者 Cheng Zuo Jinghe Jiang 《Chinese Journal of Chemical Engineering》 2026年第1期157-186,共30页
Photocatalytic nitrogen fixation (PNF) is a promising alternative to the Haber-Bosch process.It achieves green ammonia production by utilizing solar energy for nitrogen fixation under mild conditions.While nanoscale p... Photocatalytic nitrogen fixation (PNF) is a promising alternative to the Haber-Bosch process.It achieves green ammonia production by utilizing solar energy for nitrogen fixation under mild conditions.While nanoscale photocatalysts offer enhanced performance due to their high surface area and abundant active sites,their small size makes them difficult to recover and prone to agglomeration.These bottlenecks severely limit industrial application.A promising solution is to immobilize the catalysts onto support surfaces.This paper provides a systematic review of recent advances in the design of immobilized photocatalysts for ammonia synthesis.It begins by outlining the key benefits of immobilization strategies,particularly in improving catalyst stability,recyclability,and overall photocatalytic performance.The working mechanisms and features of various immobilization techniques are then categorized and explained,covering physical adsorption/deposition,chemical bonding,in situ growth,and hybrid physico-chemical methods.Supported materials and common substrate types are also summarized.Furthermore,the widely used configurations of photoreactors suitable for immobilized systems are introduced.Finally,the review identifies current research limitations and challenges,and offers perspectives on future developments in the field of immobilized photocatalysis. 展开更多
关键词 IMMOBILIZATION PHOTOCATALYSIS Nitrogen fixation support materials
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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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Programmable mixed-kernel based on MoTe_(2)/MoS_(2)heterojunction for support vector machine learning
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作者 Xinyu Huang Jiapeng Du +3 位作者 Langlang Xu Lei Tong Xiangxiang Yu Lei Ye 《Journal of Semiconductors》 2026年第3期110-116,共7页
The von Neumann bottleneck in conventional computing architectures presents a significant challenge for data-inten-sive artificial intelligence applications.A promising approach involves designing specialized hardware... The von Neumann bottleneck in conventional computing architectures presents a significant challenge for data-inten-sive artificial intelligence applications.A promising approach involves designing specialized hardware with on-chip parameter tunability,which directly accelerates machine learning functions.This work demonstrates a continuously tunable mixed-kernel function physically realized within a van der Waals heterostructure.We designed and fabricated a MoTe_(2)/MoS_(2)type-Ⅱvertical heterojunction phototransistor,which exhibits a non-monotonic,Gaussian-like optoelectronic response owing to its unique inter-layer charge transfer mechanism.This intrinsic physical behavior directly maps to a mixed-kernel function combining Gaussian and Sigmoid characteristics.Furthermore,the hardware kernel can be continuously modulated by in-situ tuning of external opti-cal stimuli.The mixed-kernel exhibited exceptional performance,achieving precision,accuracy,and area under the curve(AUC)values of 95.8%,96%,and 0.9986,respectively,significantly outperforming conventional kernels.By successfully embedding a complex,adaptable mathematical function into the intrinsic physical properties of a single device,this work pioneers a novel pathway toward next-generation,energy-efficient intelligent systems with hardware-level adaptability. 展开更多
关键词 programmable mixed-kernel HETEROJUNCTION support vector machine
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Experimental Study on Conductivity of Fractures Supported by Deep Shale in the Sichuan Basin of China
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作者 Chunting Liu Xiaozhi Shi +6 位作者 Juhui Zhu Bin Guan Subing Wang Le He Tianjun Qi Wenjun Xu Shun Qiu 《Energy Engineering》 2026年第4期472-491,共20页
To investigate the long-term fracture conductivity behavior of propped fractures under the high-temperature and high-pressure conditions of deep shale gas reservoirs in the Sichuan Basin,this study systematically anal... To investigate the long-term fracture conductivity behavior of propped fractures under the high-temperature and high-pressure conditions of deep shale gas reservoirs in the Sichuan Basin,this study systematically analyzed the effects of closure stress,proppant concentration,formation temperature,and proppant size combination.Conductivity experiments were conducted using the HXDL-2C long-term proppant conductivity evaluation system under simulated reservoir conditions to determine the time-dependent evolution of fracture conductivity.The results showed that the 50-h conductivity retention of the rock-plate experiments ranged from 22%to 28%.With increasing closure stress,fracture conductivity exhibited a rapid decline.Under a formation temperature of 120℃ and a proppant concentration of 5 kg·m^(-2),the short-term conductivity of 70/140 mesh quartz-sand-propped fractures was 2.37μm^(2)·cm,which decreased to 0.66μm^(2)·cm after long-term testing.When the closure stress increased to 80 MPa,the short-term and long-term conductivities further declined to 1.36μm^(2)·cm and 0.39μm^(2)·cm,respectively.Increasing the proppant concentration from 5 to 7.5 kg·m^(-2)at 120℃ and 80 MPa improved both short-term and long-term conductivities by enlarging the effective fracture width;however,the conductivity decay rate accelerated,and the 50-h retention dropped from 27.2%to 22.8%.Raising the temperature from 120℃ to 140℃ promoted proppant crushing and compaction,intensified shale creep,and accelerated fracture closure,reducing long-term conductivity from 0.37 to 0.30μm^(2)·cm.Under identical conditions,40/70 mesh ceramic proppants maintained significantly higher conductivities than 70/140 mesh quartz sand,with short-term and long-term values of 8.71 and 2.19μm^(2)·cm,respectively,at 120℃,80 MPa,and 5 kg·m^(-2).Pure quartz-sand systems failed to maintain effective conductivity under high-temperature and high-stress conditions,whereas adding 20%40/70 mesh ceramic proppant and thoroughly mixing it,the long-term conductivity has increased by 2.3 times,improving fracture stability while reducing overall cost.A predictive equation was derived from the experimental results to capture the dynamic decay characteristics of fracture conductivity.These outcomes provide a valuable experimental basis and technical support for optimizing fracturing fluid design,proppant selection,and operation parameters in deep shale formations. 展开更多
关键词 Deep continental shale CONDUCTIVITY supporting fractures high-temperature high-closure-pressure
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Numerical Investigation of Support-Induced Upstream Flow Disturbances in a Subsonic-Transonic Wind Tunnel
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作者 Yong Wu Zhen Fanga Bing Wang 《Fluid Dynamics & Materials Processing》 2026年第3期108-130,共23页
In wind tunnel experiments,support devices inevitably disturb the surrounding flow field,thereby degrading the accuracy of measured aerodynamic data.A new subsonic and transonic wind tunnel has recently been construct... In wind tunnel experiments,support devices inevitably disturb the surrounding flow field,thereby degrading the accuracy of measured aerodynamic data.A new subsonic and transonic wind tunnel has recently been constructed,and the support system for dynamic six degree of freedom experiments is currently under conceptual design.A key challenge is to optimize the support configuration while satisfying stringent flow quality requirements.In this study,the influence of different support configurations on the flow field is investigated numerically by analyzing velocity and pressure distributions.The results show that the optimized six degree of freedom support significantly reduces disturbances in both pressure and velocity fields,with the improvement becoming more pronounced as the Mach number increases.The main optimization measures include the addition of a tail fairing,reduction of the thickness of the connecting bases between the support rods and the sting,and downsizing of the anchor feet.In contrast,the effect of the tail support poles is found to be negligible.It is shown that,overall,the extent of upstream flow disturbance is governed primarily by the separation region and associated momentum loss induced by the support sting,the connecting bases and the anchor feet.Flow separation originates from spiral points or separation lines on the model surface,resulting from viscous effects combined with shock waves generated by the support system. 展开更多
关键词 support SUBSONIC TRANSONIC wind tunnel flow disturbance CFD simulation
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A novel scaling method for the elastic ring supporting structure of an aero-engine rotor system: analytical and experimental investigations
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作者 Lei LI Tianyue MA +4 位作者 Zhong LUO Dongwu GAO Xiangdong GE Hui MA Shibin WANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期1-18,共18页
The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometr... The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometric distortions, leading to a diminution in the predictive accuracy of the distorted similitude. To address this challenge, this study formulates a novel set of scaling laws, tailored to account for the intricate geometric distortions associated with elastic rings. The proposed scaling laws are formulated based on the intrinsic deformation characteristics of elastic rings, rather than the traditional systemic governing equations. Numerical and experimental cases are conducted to assess the efficacy and precision of the proposed scaling laws, and the obtained results are compared with those achieved by traditional methods. The outcomes demonstrate that the scaling laws put forth by this study significantly enhance the predictive capabilities for deformations of elastic rings. 展开更多
关键词 rotor system AERO-ENGINE elastic ring scaling method supporting structure
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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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