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Quantifying the Cooling Potential of Urban Tree Species:A Trait-Based Approach Using Envi-Met Simulations and Regression Analysis
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作者 Pallavi Sharma Ramkishore Singh 《Research in Ecology》 2026年第1期169-184,共16页
Urban Heat Island(UHI)effects are exacerbated by the expansion of impervious surfaces and loss of vegetation in urban centers,leading to elevated air and surface temperatures and reduced thermal comfort.Urban trees,th... Urban Heat Island(UHI)effects are exacerbated by the expansion of impervious surfaces and loss of vegetation in urban centers,leading to elevated air and surface temperatures and reduced thermal comfort.Urban trees,through shading and evapotranspiration,are among the most effective Nature-based Solutions(NbS)for passive cooling.This study assesses the cooling potential of selected tree species by analyzing their morphological and physiological traits using a combination of ENVI-met microclimate simulations and multiple regression modeling.A total of 15 urban tree species were selected from the literature and analyzed based on their dependency of their cooling efficacy.Later validated in urban setting by Envi-met simulations.Key traits,such as Leaf Area Index(LAI),canopy density,transpiration rate,tree height,rooting depth,and water availability,were analyzed.Multiple linear regression analysis was conducted to quantify the contribution of each trait to ambient temperature reduction.Results revealed that LAI(R^(2)=0.76,p<0.001)and transpiration rate(R^(2)=0.71,p<0.001)were the most significant predictors of daytime cooling,while canopy openness and tree height were more strongly correlated with nighttime heat dissipation.High-performing species,such as Ficus benghalensis,Azadirachta indica,and Samanea saman,demonstrated a maximum temperature reduction of 2.5-4.2℃,especially in compact,low-rise,and mid-rise zones.The study provides a quantitative trait-based framework for tree selection in urban greening initiatives and offers evidence to guide landscape planning and UHI mitigation strategies through scientifically informed plantation design. 展开更多
关键词 Urban Heat Island Cooling Efficacy of Tree Species regression analysis Envi-Met Simulations
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How Does Urban Public Transit Accessibility Affect Housing Prices?A Comprehensive Analysis with Geographical Detector Combined and Geographically Weighted Regression
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作者 TANG Jingjing HAN Huiran +3 位作者 YANG Chengfeng XU Lingyi GENG Hui LI Lei 《Chinese Geographical Science》 2026年第1期127-143,共17页
The accessibility of urban public transit directly influences residents’quality of life,travel behavior,and social equity.Its correlation with housing prices has garnered significant attention across disciplines such... The accessibility of urban public transit directly influences residents’quality of life,travel behavior,and social equity.Its correlation with housing prices has garnered significant attention across disciplines such as geography,economics,and urban planning.Although much existing research focuses on the impact of individual transportation facilities on housing prices,there is a notable gap in comprehensive analyses that assess the influence of overall urban transit accessibility on housing market dynamics.This study selected the main urban area of Hefei,China,as a case to investigate the spatial distribution of housing prices and evaluate public transit accessibility in 2022.Employing techniques such as the optimized parameter geographical detector and local spatial regression models,the study aimed to elucidate the effects and underlying mechanisms of urban transit accessibility on housing prices.The findings revealed that:1)housing prices in Hefei exhibited a clustered spatial pattern,with high prices concentrated in the city center and lower prices in peripheral areas,forming three distinct high-price hotspots with a‘belt-like’distribution;2)public transit accessibility showed a‘coreperiphery’structure,with accessibility declining in a‘circumferential’pattern around the city center.Based on the‘housing price-accessibility’dimension,four categories were identified:high price-high accessibility(37.25%),high price-low accessibility(19.07%),low price-high accessibility(21.95%),and low price-low accessibility(21.73%);3)the impact of transit accessibility on housing prices was spatially heterogeneous,with bus travel showing the strongest explanatory power(0.692),followed by automobile,subway,and bicycle travel.The interaction of these transportation modes generated a synergistic effect on housing price differentiation,with most influencing factors contributing more than 25%.These findings offer valuable insights for optimizing the spatial distribution of public transit infrastructure and improving both urban housing quality and residents’living standards. 展开更多
关键词 public transit accessibility housing prices geographically weighted regression geographical detector Hefei City China
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Regression analysis of squeezing-induced hybrid nanofluid flow in Darcy-Forchheimer porous medium
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作者 K.MUHAMMAD M.SARFRAZ 《Applied Mathematics and Mechanics(English Edition)》 2025年第1期193-208,共16页
This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates.One plate remains stationary,while the other moves downward at a squeezing veloci... This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates.One plate remains stationary,while the other moves downward at a squeezing velocity.The space between these plates contains a Darcy-Forchheimer porous medium.A mixture of water-based fluid with gold(Au)and silicon dioxide(Si O2)nanoparticles is formulated.In contrast to the conventional Fourier's heat flux equation,this study employs the Cattaneo-Christov heat flux equation.A uniform magnetic field is applied perpendicular to the flow direction,invoking magnetohydrodynamic(MHD)effects.Further,the model accounts for Joule heating,which is the heat generated when an electric current passes through the fluid.The problem is solved via NDSolve in MATHEMATICA.Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow,energy transport,and skin friction.The findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies.It is observed that the squeezing motion generates additional pressure gradients within the fluid,which enhances the flow rate but reduces the frictional drag.Consequently,the fluid is pushed more vigorously between the plates,increasing the flow velocity.As the fluid experiences higher flow rates due to the increased squeezing effect,it spends less time in the region between the plates.The thermal relaxation,however,abruptly changes the temperature,leading to a decrease in the temperature fluctuations. 展开更多
关键词 convective boundary condition Darcy-Forchheimer medium hybrid nanofuid Joule heating magnetohydrodynamic(MHD) numerical solution squeezing flow regression analysis
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Irreversibility analysis and multiple cubic regression based efficiency evaluation of ternary nanofluids(TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O and TiO_(2)+SiO_(2)+Cu/H_(2)O)via converging/diverging channels 被引量:1
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作者 Siddhant Taneja Sapna Sharma Bhuvaneshvar Kumar 《Acta Mechanica Sinica》 2025年第6期63-75,共13页
This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverg-ing channels.Furthermore,the study aims to assess two ternary nanofluids combinations to d... This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverg-ing channels.Furthermore,the study aims to assess two ternary nanofluids combinations to determine which configuration can provide better heat and mass transfer and lower entropy production,while ensuring cost efficiency.This work bridges the gap be-tween academic research and industrial feasibility by incorporating cost analysis,entropy generation,and thermal efficiency.To compare the velocity,temperature,and concentration profiles,we examine two ternary nanofluids,i.e.,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O and TiO_(2)+SiO_(2)+Cu/H_(2)O,while considering the shape of nanoparticles.The velocity slip and Soret/Dufour effects are taken into consideration.Furthermore,regression analysis for Nusselt and Sherwood numbers of the model is carried out.The Runge-Kutta fourth-order method with shooting technique is employed to acquire the numerical solution of the governed system of ordinary differential equations.The flow pattern attributes of ternary nanofluids are meticulously examined and simulated with the fluc-tuation of flow-dominating parameters.Additionally,the influence of these parameters is demonstrated in the flow,temperature,and concentration fields.For variation in Eckert and Dufour numbers,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher temperature than TiO_(2)+SiO_(2)+Cu/H_(2)O.The results obtained indicate that the ternary nanofluid TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher heat transfer rate,lesser entropy generation,greater mass transfer rate,and lower cost than that of TiO_(2)+SiO_(2)+Cu/H_(2)O ternary nanofluid. 展开更多
关键词 Converging/Diverging channels Ternary nanofluids Multiple cubic regression Entropy generation
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Model’s parameter sensitivity assessment and their impact on Urban Densification using regression analysis
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作者 Anasua Chakraborty Mitali Yeshwant Joshi +2 位作者 Ahmed Mustafa Mario Cools Jacques Teller 《Geography and Sustainability》 2025年第2期143-156,共14页
The impact of different global and local variables in urban development processes requires a systematic study to fully comprehend the underlying complexities in them.The interplay between such variables is crucial for... The impact of different global and local variables in urban development processes requires a systematic study to fully comprehend the underlying complexities in them.The interplay between such variables is crucial for modelling urban growth to closely reflects reality.Despite extensive research,ambiguity remains about how variations in these input variables influence urban densification.In this study,we conduct a global sensitivity analysis(SA)using a multinomial logistic regression(MNL)model to assess the model’s explanatory and predictive power.We examine the influence of global variables,including spatial resolution,neighborhood size,and density classes,under different input combinations at a provincial scale to understand their impact on densification.Additionally,we perform a stepwise regression to identify the significant explanatory variables that are important for understanding densification in the Brussels Metropolitan Area(BMA).Our results indicate that a finer spatial resolution of 50 m and 100 m,smaller neighborhood size of 5×5 and 3×3,and specific density classes—namely 3(non-built-up,low and high built-up)and 4(non-built-up,low,medium and high built-up)—optimally explain and predict urban densification.In line with the same,the stepwise regression reveals that models with a coarser resolution of 300 m lack significant variables,reflecting a lower explanatory power for densification.This approach aids in identifying optimal and significant global variables with higher explanatory power for understanding and predicting urban densification.Furthermore,these findings are reproducible in a global urban context,offering valuable insights for planners,modelers and geographers in managing future urban growth and minimizing modelling. 展开更多
关键词 Urban densification Sensitivity analysis Multinomial logistic regression Stepwise regression
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Subgroup Analysis of a Single-Index Threshold Penalty Quantile Regression Model Based on Variable Selection
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作者 QI Hui XUE Yaxin 《Wuhan University Journal of Natural Sciences》 2025年第2期169-183,共15页
In clinical research,subgroup analysis can help identify patient groups that respond better or worse to specific treatments,improve therapeutic effect and safety,and is of great significance in precision medicine.This... In clinical research,subgroup analysis can help identify patient groups that respond better or worse to specific treatments,improve therapeutic effect and safety,and is of great significance in precision medicine.This article considers subgroup analysis methods for longitudinal data containing multiple covariates and biomarkers.We divide subgroups based on whether a linear combination of these biomarkers exceeds a predetermined threshold,and assess the heterogeneity of treatment effects across subgroups using the interaction between subgroups and exposure variables.Quantile regression is used to better characterize the global distribution of the response variable and sparsity penalties are imposed to achieve variable selection of covariates and biomarkers.The effectiveness of our proposed methodology for both variable selection and parameter estimation is verified through random simulations.Finally,we demonstrate the application of this method by analyzing data from the PA.3 trial,further illustrating the practicality of the method proposed in this paper. 展开更多
关键词 longitudinal data subgroup analysis threshold model quantile regression variable selection
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A logistic-Lasso-regression-based seismic fragility analysis method for electrical equipment considering structural and seismic parameter uncertainty
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作者 Cui Jiawei Che Ailan +1 位作者 Li Sheng Cheng Yongfeng 《Earthquake Engineering and Engineering Vibration》 2025年第1期169-186,共18页
Damage to electrical equipment in an earthquake can lead to power outage of power systems.Seismic fragility analysis is a common method to assess the seismic reliability of electrical equipment.To further guarantee th... Damage to electrical equipment in an earthquake can lead to power outage of power systems.Seismic fragility analysis is a common method to assess the seismic reliability of electrical equipment.To further guarantee the efficiency of analysis,multi-source uncertainties including the structure itself and seismic excitation need to be considered.A method for seismic fragility analysis that reflects structural and seismic parameter uncertainty was developed in this study.The proposed method used a random sampling method based on Latin hypercube sampling(LHS)to account for the structure parameter uncertainty and the group structure characteristics of electrical equipment.Then,logistic Lasso regression(LLR)was used to find the seismic fragility surface based on double ground motion intensity measures(IM).The seismic fragility based on the finite element model of an±1000 kV main transformer(UHVMT)was analyzed using the proposed method.The results show that the seismic fragility function obtained by this method can be used to construct the relationship between the uncertainty parameters and the failure probability.The seismic fragility surface did not only provide the probabilities of seismic damage states under different IMs,but also had better stability than the fragility curve.Furthermore,the sensitivity analysis of the structural parameters revealed that the elastic module of the bushing and the height of the high-voltage bushing may have a greater influence. 展开更多
关键词 seismic fragility UNCERTAINTY logistic lasso regression ±1000 kV main transformer sensitivity analysis
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Two Eras of Despair:A Long-Term Trend Analysis of Deaths of Despair in Central and Eastern Europe and Central Asia
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作者 Eun Hae Lee Minjae Choi +5 位作者 Hanul Park Joon Hee Han Sujeong Yu Joshua Kirabo Sempungu Inbae Sohn Yo Han Lee 《International Journal of Mental Health Promotion》 2026年第1期60-71,共12页
Background:That Central and Eastern Europe and Central Asia(CEECA)experienced a major mortality crisis in the 1990s is a well-established finding,with most analyses focusing on singular causes like alcohol-related dea... Background:That Central and Eastern Europe and Central Asia(CEECA)experienced a major mortality crisis in the 1990s is a well-established finding,with most analyses focusing on singular causes like alcohol-related deaths.However,the utility of the integrated“deaths of despair”framework,which views alcohol,drug,and suicide deaths as a unified socio-economic phenomenon,remains under-explored in this context.Crucially,the long-term evolution of the composition of despair within the region remains a largely unexplored area of inquiry.Therefore,this study aims to analyze the long-term trends,changing composition,and regional heterogeneity of deaths from despair in the CEECA region from 1980 to 2021.Methods:Using 2021 Global Burden of Disease(GBD)data(1980–2021),we analyzed deaths of despair mortality trends in 29 CEECA countries.We employed Joinpoint regression to identify significant trend changes and conducted stratified analyses by cause,gender,and age group.Results:The CEECA deaths of despair crisis began as an alcohol and suicide driven phenomenon concentrated in middle-aged men(50–74 years)during the 1990s,with mortality rates for alcohol use disorders and self-harm surging annually by 30.35%(p=0.002)and 13.44%(p=0.001),respectively,between 1991 and 1994.It has since evolved,marked by a contrasting and emerging threat in the 21st century:a rising proportion of drug-related deaths among the younger(15–49 years)male cohort,where the share of drug use disorders increased from 6.9%in 2000 to 11.8%in 2008.Conclusion:The deaths of despair crisis in the CEECA region is not a past event but an ongoing,evolving phenomenon.Its changing nature demands a shift in public health focus from solely historical drivers to new,generation-specific threats,particularly the rise of drug-related despair among youth. 展开更多
关键词 Deaths of despair post-socialism transition Central and Eastern Europe and Central Asia(CEECA) mortality trends joinpoint regression analysis
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Multiple Linear Regression Analysis of Vertical Distribution of Near-Shore Suspended Sediment
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作者 Mengmeng Wei Wenjin Zhu +1 位作者 Xiaotian Dong Xingyuan Chen 《Journal of Environmental Science and Engineering(B)》 2025年第1期11-18,共8页
According to some main assumptions in the Rouse Formula,it analyzes the applicability of Rouse distribution in the coastal region.Based on the classical Rouse Formula,the linear form of Rouse Formula and the transport... According to some main assumptions in the Rouse Formula,it analyzes the applicability of Rouse distribution in the coastal region.Based on the classical Rouse Formula,the linear form of Rouse Formula and the transport characteristics of offshore sediment were used to take lnz/h,lnc_(a),c_(a),u,lnu and z/h as the independent variables.The multiple liner regression method was used to analyze the influence of the independent variables on the vertical distribution of sediment concentration.By using the method of significance test,the factors(lnu)that have less influence on sediment concentration among 6 variables were eliminated.The correlation coefficient between the calculated sediment concentration and the measured sediment concentration indicates that the adopted variables can reflect the characteristics of vertical distribution of concentration of fine sediment near shore under complex dynamic conditions. 展开更多
关键词 Rouse Formula multiple linear regression vertical distribution of suspended sediment Hai’an Bay
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Changes in border-associated macrophages after stroke: Single-cell sequencing analysis 被引量:2
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作者 Ning Yu Yang Zhao +3 位作者 Peng Wang Fuqiang Zhang Cuili Wen Shilei Wang 《Neural Regeneration Research》 2026年第1期346-356,共11页
Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macro... Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macrophages have been poorly understood and largely overlooked. However, a recent study reported that border-associated macrophages participate in stroke-induced inflammation, although many details and the underlying mechanisms remain unclear. In this study, we performed a comprehensive single-cell analysis of mouse border-associated macrophages using sequencing data obtained from the Gene Expression Omnibus(GEO) database(GSE174574 and GSE225948). Differentially expressed genes were identified, and enrichment analysis was performed to identify the transcription profile of border-associated macrophages. CellChat analysis was conducted to determine the cell communication network of border-associated macrophages. Transcription factors were predicted using the ‘pySCENIC' tool. We found that, in response to hypoxia, borderassociated macrophages underwent dynamic transcriptional changes and participated in the regulation of inflammatory-related pathways. Notably, the tumor necrosis factor pathway was activated by border-associated macrophages following ischemic stroke. The pySCENIC analysis indicated that the activity of signal transducer and activator of transcription 3(Stat3) was obviously upregulated in stroke, suggesting that Stat3 inhibition may be a promising strategy for treating border-associated macrophages-induced neuroinflammation. Finally, we constructed an animal model to investigate the effects of border-associated macrophages depletion following a stroke. Treatment with liposomes containing clodronate significantly reduced infarct volume in the animals and improved neurological scores compared with untreated animals. Taken together, our results demonstrate comprehensive changes in border-associated macrophages following a stroke, providing a theoretical basis for targeting border-associated macrophages-induced neuroinflammation in stroke treatment. 展开更多
关键词 border-associated macrophages CLODRONATE hypoxia ISCHEMIA-REPERFUSION ischemic stroke liposomes neuroinflammation single-cell sequencing analysis STAT3 tumor necrosis factor
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Risk factors for paternal perinatal depression in Chinese advanced maternal age couples:A regression mixture model
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作者 Xing Yin Juan Du +1 位作者 Shao-Lian Cai Xing-Qiang Chen 《World Journal of Psychiatry》 2026年第1期267-277,共11页
BACKGROUND Paternal perinatal depression(PPD)is closely associated with maternal mental health challenges,marital strain,and adverse child developmental outcomes.Despite its significant impact,PPD remains under-recogn... BACKGROUND Paternal perinatal depression(PPD)is closely associated with maternal mental health challenges,marital strain,and adverse child developmental outcomes.Despite its significant impact,PPD remains under-recognized in family-centered clinical practice.Concurrently,against the backdrop of rising rates of delayed marriage and China’s Maternity Incentive Policy,the proportion of women giving birth at an advanced maternal age is increasing.Nevertheless,research specifically examining PPD among spouses of older mothers remains critically scarce,both in China and globally.AIM To investigate PPD and its influencing factors in Chinese advanced maternal age families.METHODS This cross-sectional study included 358 participants;it was conducted among fathers of pregnant women of advanced maternal age at five hospitals in the Pearl River Delta region of China from September 2023 to June 2024.Data were collected via a general information questionnaire,the Social Support Rating Scale,and the Edinburgh Postnatal Depression Scale.Latent profile analysis and regression mixture models(RMMs)were adopted to analyze the latent PPD types and factors that influenced PPD.RESULTS The incidence of PPD was 16.48%,and three profiles were identified:Low-symptomatic(175 cases,48.89%),monophasic(140 cases,39.10%),and high-symptomatic(43 cases,12.01%).The RMM analysis revealed that first pregnancy,low income(<¥3000/month),part-time work,and a history of abnormal pregnancy were positively associated with the high-symptomatic type(P<0.05).Conversely,high subjective support and support utilization were negatively associated with the high-symptomatic type compared with the low-symptomatic type(P<0.05).Good couple relationships,high objective and subjective support,and high support utilization were negatively associated with monophasic disorder(P<0.05).CONCLUSION PPD incidence is high among Chinese fathers with advanced maternal age partners,and the characteristics of depression are varied.Healthcare practitioners should prioritize individuals with low levels of social support. 展开更多
关键词 Advanced maternal age Paternal perinatal depression Fathers’mental health regression mixture model Advanced-age pregnancy Latent profile analysis
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Stability analysis of distributed Kalman filtering algorithm for stochastic regression model
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作者 Siyu Xie Die Gan Zhixin Liu 《Control Theory and Technology》 2025年第2期161-175,共15页
The work proposes a distributed Kalman filtering(KF)algorithm to track a time-varying unknown signal process for a stochastic regression model over network systems in a cooperative way.We provide the stability analysi... The work proposes a distributed Kalman filtering(KF)algorithm to track a time-varying unknown signal process for a stochastic regression model over network systems in a cooperative way.We provide the stability analysis of the proposed distributed KF algorithm without independent and stationary signal assumptions,which implies that the theoretical results are able to be applied to stochastic feedback systems.Note that the main difficulty of stability analysis lies in analyzing the properties of the product of non-independent and non-stationary random matrices involved in the error equation.We employ analysis techniques such as stochastic Lyapunov function,stability theory of stochastic systems,and algebraic graph theory to deal with the above issue.The stochastic spatio-temporal cooperative information condition shows the cooperative property of multiple sensors that even though any local sensor cannot track the time-varying unknown signal,the distributed KF algorithm can be utilized to finish the filtering task in a cooperative way.At last,we illustrate the property of the proposed distributed KF algorithm by a simulation example. 展开更多
关键词 Distributed Kalman filtering algorithm Stochastic cooperative information condition Sensor networks (L_(p))-exponential stability Stochastic regression model
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Crystal structure,thermal analysis,and luminescence properties of six heterocyclic lanthanide complexes
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作者 SONG Zihe ZHAO Jinjin +1 位作者 REN Ning ZHANG Jianjun 《无机化学学报》 北大核心 2026年第1期181-192,共12页
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'... Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6. 展开更多
关键词 lanthanide complexes fluorescence property crystal structure thermal analysis
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Cavity ring-down spectroscopy CO gas sensor integrating principal component analysis with savitzky-golay filtering
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作者 GUO Zi-long SHI Cheng-rui +4 位作者 DONG Yuan-yuan ZHANG Lei SUN Xiao-yuan SUN Jing-jing ZHOU Sheng 《中国光学(中英文)》 北大核心 2026年第1期179-189,共11页
The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recogni... The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recognized to be limited at data boundaries and high frequencies,which can significantly reduce the signal-to-noise ratio(SNR).To solve this problem,a novel method synergistically integrating Principal Component Analysis(PCA)with SG filtering is proposed in this paper.This approach avoids the is-sue of excessive smoothing associated with larger window sizes.The proposed PCA-SG filtering algorithm was applied to a CO gas sensing system based on Cavity Ring-Down Spectroscopy(CRDS).The perform-ance of the PCA-SG filtering algorithm is demonstrated through comparison with Moving Average Filtering(MAF),Wavelet Transformation(WT),Kalman Filtering(KF),and the SG filter.The results demonstrate that the proposed algorithm exhibits superior noise reduction capabilities compared to the other algorithms evaluated.The SNR of the ring-down signal was improved from 11.8612 dB to 29.0913 dB,and the stand-ard deviation of the extracted ring-down time constant was reduced from 0.037μs to 0.018μs.These results confirm that the proposed PCA-SG filtering algorithm effectively improves the smoothness of the ring-down curve data,demonstrating its feasibility. 展开更多
关键词 cavity ring-down spectroscopy CO gas sensor principal component analysis Savitzky-Golay filter
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Global,regional,and national burdens of acute respiratory infections among children and adolescents from 1990 to 2021:A systematic analysis
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作者 Xiang Meng Sijie Li +4 位作者 Meiyan Li Husheng Xiong Xuejuan Chen Yonghui Zhong Dingmei Zhang 《Asian Pacific Journal of Tropical Medicine》 2026年第2期51-60,I0001-I0061,共71页
Objective:To evaluate the global,regional,and national burden and determinants of Acute Respiratory Infections(ARIs)among children and adolescents from 1990 to 2021.Methods:We analysed ARI mortality and disability-adj... Objective:To evaluate the global,regional,and national burden and determinants of Acute Respiratory Infections(ARIs)among children and adolescents from 1990 to 2021.Methods:We analysed ARI mortality and disability-adjusted life years(DALYs),stratified by age,sex,and economic development level based on data retrieved from the Global Burden of Disease study 2021.Decomposition and frontier analyses were employed to identify key drivers of burden variation and visualize potential reductions based on development levels.Results:Between 1990 and 2021,the global burden of ARIs showed a significant decline in both achievable age-standardized DALYs rate and age-standardized mortality rates(EAPC=-3.87 and-3.81,respectively).Different age groups and sex witnessed different levels of ARI burden,males experienced heavier burden than females and the 0-4 years-old group experienced heavier burden than other study age groups.Most of the 204 countries and territories experienced a downward trend of ARI burden,with slight increases observed only in Lesotho and Dominica.A negative correlation was found between the Socio-demographic Index and ARI burden.Decomposition analysis indicated that the significant decreases in deaths and DALYs were primarily driven by epidemiological changes.Conclusions:The global burden of ARIs among children and adolescents has declined over the past three decades,but substantial regional disparities persist.Targeted public health strategies are needed to address the continued ARI burden in high-risk regions and vulnerable age groups. 展开更多
关键词 Respiratory infection Global disease burden Decomposition analysis Frontier analysis
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Artificial intelligence-assisted non-metallic inclusion particle analysis in advanced steels using machine learning:A review
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作者 Gonghao Lian Xiaoming Liu +3 位作者 Qiang Wang Chunguang Shen Yi Wang Wangzhong Mu 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期401-416,共16页
The detection and characterization of non-metallic inclusions are essential for clean steel production.Recently,imaging analysis combined with high-dimensional data processing of metallic materials using artificial in... The detection and characterization of non-metallic inclusions are essential for clean steel production.Recently,imaging analysis combined with high-dimensional data processing of metallic materials using artificial intelligence(AI)-based machine learning(ML)has developed rapidly.This technique has achieved impressive results in the field of inclusion classification in process metallurgy.The present study surveys the ML modeling of inclusion prediction in advanced steels,including the detection,classification,and feature prediction of inclusions in different steel grades.Studies on clean steel with different features based on data and image analysis via ML are summarized.Regarding the data analysis,the inclusion prediction methodology based on ML establishes a connection between the experimental parameters and inclusion characteristics and analyzes the importance of the experimental parameters.Regarding the image analysis,the focus is placed on the classification of different types of inclusions via deep learning,in comparison with data analysis.Finally,further development of inclusion analyses using ML-based methods is recommended.This work paves the way for the application of AIbased methodologies for ultraclean-steel studies from a sustainable metallurgy perspective. 展开更多
关键词 machine learning inclusion classification image analysis data analysis clean steel
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基于InVSET-Ridge Regression-PLUS模型的云贵高原碳储量时空演变及多情景预测
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作者 李媛 彭玉玲 +1 位作者 彭浩纳 程为颖 《环境科学》 北大核心 2026年第3期1928-1940,共13页
碳储量作为衡量生态系统碳汇能力的关键指标,对全球气候变化的缓解具有重要意义.结合机器学习和生态系统服务模型的优势,构建基于InVEST-Ridge Regression-PLUS模型的综合分析框架,对云贵高原2000~2020年碳储量的时空演变特征及其驱动... 碳储量作为衡量生态系统碳汇能力的关键指标,对全球气候变化的缓解具有重要意义.结合机器学习和生态系统服务模型的优势,构建基于InVEST-Ridge Regression-PLUS模型的综合分析框架,对云贵高原2000~2020年碳储量的时空演变特征及其驱动机制进行定量分析,并据此设计未来情景,预测不同土地利用路径下区域碳储量的变化趋势.结果表明:(1)云贵高原2000~2020年间碳储量总体呈缓慢增长的趋势,且增长速率不断下降,表现为“南高北低”的分布特征.(2)植被覆盖度是影响该区域碳储量的决定性因素,不同土地利用类型之间的转化会影响碳储量空间分布及变化趋势.(3)在未来情景模拟中,碳汇提升情景下的碳储量表现最优,有效验证了退耕还林和草地恢复等生态工程的作用,为云贵高原及同类型喀斯特地区的碳储量动态评估与优化提供科学依据. 展开更多
关键词 云贵高原 碳储量 InVEST模型 岭回归 PLUS模型
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A Unified Feature Selection Framework Combining Mutual Information and Regression Optimization for Multi-Label Learning
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作者 Hyunki Lim 《Computers, Materials & Continua》 2026年第4期1262-1281,共20页
High-dimensional data causes difficulties in machine learning due to high time consumption and large memory requirements.In particular,in amulti-label environment,higher complexity is required asmuch as the number of ... High-dimensional data causes difficulties in machine learning due to high time consumption and large memory requirements.In particular,in amulti-label environment,higher complexity is required asmuch as the number of labels.Moreover,an optimization problem that fully considers all dependencies between features and labels is difficult to solve.In this study,we propose a novel regression-basedmulti-label feature selectionmethod that integrates mutual information to better exploit the underlying data structure.By incorporating mutual information into the regression formulation,the model captures not only linear relationships but also complex non-linear dependencies.The proposed objective function simultaneously considers three types of relationships:(1)feature redundancy,(2)featurelabel relevance,and(3)inter-label dependency.These three quantities are computed usingmutual information,allowing the proposed formulation to capture nonlinear dependencies among variables.These three types of relationships are key factors in multi-label feature selection,and our method expresses them within a unified formulation,enabling efficient optimization while simultaneously accounting for all of them.To efficiently solve the proposed optimization problem under non-negativity constraints,we develop a gradient-based optimization algorithm with fast convergence.Theexperimental results on sevenmulti-label datasets show that the proposed method outperforms existingmulti-label feature selection techniques. 展开更多
关键词 feature selection multi-label learning regression model optimization mutual information
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Integrated transcriptome and metabolome analysis reveals light induction of anthocyanin rapid accumulation in red-fleshed peach after pre-harvest bagging
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作者 Jia Wei Fengjie He +6 位作者 Kexin Sun Li Wang Yiming Yin Junbei Ni Songling Bai Yuanwen Teng Huijuan Jia 《Horticultural Plant Journal》 2026年第3期539-554,共16页
Red-fleshed fruits are valued for their vibrant color and high anthocyanin content.Pre-harvest fruit bagging enhances fruit peel pigmentation,but its effect on flesh coloration remains poorly characterized.This study ... Red-fleshed fruits are valued for their vibrant color and high anthocyanin content.Pre-harvest fruit bagging enhances fruit peel pigmentation,but its effect on flesh coloration remains poorly characterized.This study revealed that removing bags from‘Gengcunyangtao’red-fleshed peach fruits triggers the rapid and uniform accumulation of anthocyanins in the flesh,resulting in anthocyanin levels that exceed those in unbagged fruits.The exposure to light after bag removal triggered significant increases in anthocyanin levels within 24 h.This was accompanied by the rapid upregulation of light-responsive and flavonoid biosynthetic gene expression levels within 6 h.A metabolomic analysis indicated that anthocyanin precursors,especially p-coumaric acid,accumulated before bag removal,thereby increasing substrate availability for rapid anthocyanin synthesis.On the basis of a weighted gene co-expression network analysis,MYB transcription factors,anthocyanin transporters,glutathione S-transferase,and multidrug and toxic compound extrusion(MATE)were identified as key regulators that coordinate precursor storage along with light-induced transcriptional activation.Notably,PpMYB4 binds to the promoter of PpGSTF14 and activates its expression,thereby promoting anthocyanin accumulation.The study findings elucidated the temporal coordination of metabolic priming and light-responsive transcriptional regulation driving rapid anthocyanin biosynthesis,with possible implications for improving peach fruit flesh coloration. 展开更多
关键词 Red-fleshed peach ANTHOCYANIN Pre-harvest fruit bagging Light exposure Transcriptome analysis Metabolome analysis
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Cloning and Bioinformatics Analysis of DsCBL4 Gene from Dianthus spiculifolius Schur
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作者 Di Haoyang Hou Xinyang +4 位作者 Li Yan You Xue Yu Yuxin Wang Jingang Zhang Haizhen 《Journal of Northeast Agricultural University(English Edition)》 2026年第1期22-34,共13页
Dianthus spiculifolius Schur,as an emerging ornamental plant,has extensive applications and economic values.In this study,the DsCBL4 gene was successfully cloned,and its tissue-specific expression,expression patterns ... Dianthus spiculifolius Schur,as an emerging ornamental plant,has extensive applications and economic values.In this study,the DsCBL4 gene was successfully cloned,and its tissue-specific expression,expression patterns under various abiotic stresses,subcellular localization,and bioinformatics analysis of the encoded amino acid sequence were conducted.The results showed that the coding region of the DsCBL4 gene was 675 bp long,encoding 224 amino acids.It had high homology with the amino acids encoded by Amaranthus tricolor,Chenopodium quinoa and Spinacia oleracea.The predicted relative molecular mass of DsCBL4 was 25.61 ku,with an isoelectric point of 4.58,and it had phosphorylation sites,belonging to an unstable hydrophilic protein.Its secondary structure includedα-helices,irregular coils and extended chains.The tertiary structure prediction revealed that DsCBL4 had four EFhand calcium-binding domains necessary for Ca2+binding in plant calmodulin-like proteins and the FPSF motif for calcineurin B-like protein(CBL)-interacting protein kinase(CIPK)activation.The expression level of the DsCBL4 gene showed tissue specificity,with the highest expression in roots.It was induced by drought,low temperature,combined drought and low temperature,salt stress,nitrogen stress,phosphorus stress,calcium ion stress,high temperature stress,and abscisic acid(ABA)stress.Both transient infection in Nicotiana tabacum L.and stable expression in transgenic Arabidopsis thaliana showed that the DsCBL4 protein was localized to the cell membrane.These results suggested that DsCBL4 might be involved in the abiotic stress response of Dianthus spiculifolius through the calcium signaling pathway,providing a theoretical basis for understanding its molecular mechanism.This study provided an important reference for further exploring the role of the DsCBLs gene family in plant stress resistance. 展开更多
关键词 Dianthus spiculifolius Schur CBL4 gene gene cloning expression analysis structural analysis
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